ALSA: scarlett2: Rename scarlett_gen2 to scarlett2
authorGeoffrey D. Bennett <g@b4.vu>
Thu, 26 Oct 2023 18:01:28 +0000 (04:31 +1030)
committerTakashi Iwai <tiwai@suse.de>
Fri, 27 Oct 2023 09:22:59 +0000 (11:22 +0200)
This driver was originally developed for the Focusrite Scarlett Gen 2
series. Since then Focusrite have used a similar protocol for their
Gen 3, Gen 4, Clarett USB, Clarett+, and Vocaster series.

Let's call this common protocol the "Scarlett 2 Protocol" and rename
the driver to scarlett2 to not imply that it is restricted to Gen 2
series devices.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/e1ad7f69a1e20cdb39094164504389160c1a0a0b.1698342632.git.g@b4.vu
Signed-off-by: Takashi Iwai <tiwai@suse.de>
MAINTAINERS
sound/usb/Makefile
sound/usb/mixer_quirks.c
sound/usb/mixer_scarlett2.c [new file with mode: 0644]
sound/usb/mixer_scarlett2.h [new file with mode: 0644]
sound/usb/mixer_scarlett_gen2.c [deleted file]
sound/usb/mixer_scarlett_gen2.h [deleted file]

index 0495c2644698cc777eb5826ce38cd3cf7be79200..0cabc58100f4f40d66a61d5371f4826139ba5f81 100644 (file)
@@ -8126,7 +8126,7 @@ M:        Geoffrey D. Bennett <g@b4.vu>
 L:     alsa-devel@alsa-project.org (moderated for non-subscribers)
 S:     Maintained
 T:     git git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git
-F:     sound/usb/mixer_scarlett_gen2.c
+F:     sound/usb/mixer_scarlett2.c
 
 FORCEDETH GIGABIT ETHERNET DRIVER
 M:     Rain River <rain.1986.08.12@gmail.com>
index db5ff76d0e61f901bf5ca1f74a82a35385db9862..8c657c2753c84f0f36f5a305de731f85e4d7d806 100644 (file)
@@ -12,7 +12,7 @@ snd-usb-audio-objs :=         card.o \
                        mixer.o \
                        mixer_quirks.o \
                        mixer_scarlett.o \
-                       mixer_scarlett_gen2.o \
+                       mixer_scarlett2.o \
                        mixer_us16x08.o \
                        mixer_s1810c.o \
                        pcm.o \
index ac521b71cb57106eac37e97f9f0742f105236ae0..898bc3baca7b994ef202e80ecbff93288ddc7bba 100644 (file)
@@ -33,7 +33,7 @@
 #include "mixer.h"
 #include "mixer_quirks.h"
 #include "mixer_scarlett.h"
-#include "mixer_scarlett_gen2.h"
+#include "mixer_scarlett2.h"
 #include "mixer_us16x08.h"
 #include "mixer_s1810c.h"
 #include "helper.h"
@@ -3426,7 +3426,7 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
        case USB_ID(0x1235, 0x820a): /* Focusrite Clarett+ 2Pre */
        case USB_ID(0x1235, 0x820b): /* Focusrite Clarett+ 4Pre */
        case USB_ID(0x1235, 0x820c): /* Focusrite Clarett+ 8Pre */
-               err = snd_scarlett_gen2_init(mixer);
+               err = snd_scarlett2_init(mixer);
                break;
 
        case USB_ID(0x041e, 0x323b): /* Creative Sound Blaster E1 */
diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c
new file mode 100644 (file)
index 0000000..d003a61
--- /dev/null
@@ -0,0 +1,4314 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *   Focusrite Scarlett 2 Protocol Driver for ALSA
+ *   (including Scarlett 2nd Gen, 3rd Gen, Clarett USB, and Clarett+
+ *   series products)
+ *
+ *   Supported models:
+ *   - 6i6/18i8/18i20 Gen 2
+ *   - Solo/2i2/4i4/8i6/18i8/18i20 Gen 3
+ *   - Clarett 2Pre/4Pre/8Pre USB
+ *   - Clarett+ 2Pre/4Pre/8Pre
+ *
+ *   Copyright (c) 2018-2023 by Geoffrey D. Bennett <g at b4.vu>
+ *   Copyright (c) 2020-2021 by Vladimir Sadovnikov <sadko4u@gmail.com>
+ *   Copyright (c) 2022 by Christian Colglazier <christian@cacolglazier.com>
+ *
+ *   Based on the Scarlett (Gen 1) Driver for ALSA:
+ *
+ *   Copyright (c) 2013 by Tobias Hoffmann
+ *   Copyright (c) 2013 by Robin Gareus <robin at gareus.org>
+ *   Copyright (c) 2002 by Takashi Iwai <tiwai at suse.de>
+ *   Copyright (c) 2014 by Chris J Arges <chris.j.arges at canonical.com>
+ *
+ *   Many codes borrowed from audio.c by
+ *     Alan Cox (alan at lxorguk.ukuu.org.uk)
+ *     Thomas Sailer (sailer at ife.ee.ethz.ch)
+ *
+ *   Code cleanup:
+ *   David Henningsson <david.henningsson at canonical.com>
+ */
+
+/* The protocol was reverse engineered by looking at the communication
+ * between Focusrite Control 2.3.4 and the Focusrite(R) Scarlett 18i20
+ * (firmware 1083) using usbmon in July-August 2018.
+ *
+ * Scarlett 18i8 support added in April 2019.
+ *
+ * Scarlett 6i6 support added in June 2019 (thanks to Martin Wittmann
+ * for providing usbmon output and testing).
+ *
+ * Scarlett 4i4/8i6 Gen 3 support added in May 2020 (thanks to Laurent
+ * Debricon for donating a 4i4 and to Fredrik Unger for providing 8i6
+ * usbmon output and testing).
+ *
+ * Scarlett 18i8/18i20 Gen 3 support added in June 2020 (thanks to
+ * Darren Jaeckel, Alex Sedlack, and Clovis Lunel for providing usbmon
+ * output, protocol traces and testing).
+ *
+ * Support for loading mixer volume and mux configuration from the
+ * interface during driver initialisation added in May 2021 (thanks to
+ * Vladimir Sadovnikov for figuring out how).
+ *
+ * Support for Solo/2i2 Gen 3 added in May 2021 (thanks to Alexander
+ * Vorona for 2i2 protocol traces).
+ *
+ * Support for phantom power, direct monitoring, speaker switching,
+ * and talkback added in May-June 2021.
+ *
+ * Support for Clarett+ 8Pre added in Aug 2022 by Christian
+ * Colglazier.
+ *
+ * Support for Clarett 8Pre USB added in Sep 2023 (thanks to Philippe
+ * Perrot for confirmation).
+ *
+ * Support for Clarett+ 4Pre and 2Pre added in Sep 2023 (thanks to
+ * Gregory Rozzo for donating a 4Pre, and David Sherwood and Patrice
+ * Peterson for usbmon output).
+ *
+ * Support for Clarett 2Pre and 4Pre USB added in Oct 2023.
+ *
+ * This ALSA mixer gives access to (model-dependent):
+ *  - input, output, mixer-matrix muxes
+ *  - mixer-matrix gain stages
+ *  - gain/volume/mute controls
+ *  - level meters
+ *  - line/inst level, pad, and air controls
+ *  - phantom power, direct monitor, speaker switching, and talkback
+ *    controls
+ *  - disable/enable MSD mode
+ *  - disable/enable standalone mode
+ *
+ * <ditaa>
+ *    /--------------\    18chn            20chn     /--------------\
+ *    | Hardware  in +--+------\    /-------------+--+ ALSA PCM out |
+ *    \--------------/  |      |    |             |  \--------------/
+ *                      |      |    |    /-----\  |
+ *                      |      |    |    |     |  |
+ *                      |      v    v    v     |  |
+ *                      |   +---------------+  |  |
+ *                      |    \ Matrix  Mux /   |  |
+ *                      |     +-----+-----+    |  |
+ *                      |           |          |  |
+ *                      |           |18chn     |  |
+ *                      |           |          |  |
+ *                      |           |     10chn|  |
+ *                      |           v          |  |
+ *                      |     +------------+   |  |
+ *                      |     | Mixer      |   |  |
+ *                      |     |     Matrix |   |  |
+ *                      |     |            |   |  |
+ *                      |     | 18x10 Gain |   |  |
+ *                      |     |   stages   |   |  |
+ *                      |     +-----+------+   |  |
+ *                      |           |          |  |
+ *                      |18chn      |10chn     |  |20chn
+ *                      |           |          |  |
+ *                      |           +----------/  |
+ *                      |           |             |
+ *                      v           v             v
+ *                      ===========================
+ *               +---------------+       +--—------------+
+ *                \ Output  Mux /         \ Capture Mux /
+ *                 +---+---+---+           +-----+-----+
+ *                     |   |                     |
+ *                10chn|   |                     |18chn
+ *                     |   |                     |
+ *  /--------------\   |   |                     |   /--------------\
+ *  | S/PDIF, ADAT |<--/   |10chn                \-->| ALSA PCM in  |
+ *  | Hardware out |       |                         \--------------/
+ *  \--------------/       |
+ *                         v
+ *                  +-------------+    Software gain per channel.
+ *                  | Master Gain |<-- 18i20 only: Switch per channel
+ *                  +------+------+    to select HW or SW gain control.
+ *                         |
+ *                         |10chn
+ *  /--------------\       |
+ *  | Analogue     |<------/
+ *  | Hardware out |
+ *  \--------------/
+ * </ditaa>
+ *
+ * Gen 3 devices have a Mass Storage Device (MSD) mode where a small
+ * disk with registration and driver download information is presented
+ * to the host. To access the full functionality of the device without
+ * proprietary software, MSD mode can be disabled by:
+ * - holding down the 48V button for five seconds while powering on
+ *   the device, or
+ * - using this driver and alsamixer to change the "MSD Mode" setting
+ *   to Off and power-cycling the device
+ */
+
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/moduleparam.h>
+
+#include <sound/control.h>
+#include <sound/tlv.h>
+
+#include "usbaudio.h"
+#include "mixer.h"
+#include "helper.h"
+
+#include "mixer_scarlett2.h"
+
+/* device_setup value to allow turning MSD mode back on */
+#define SCARLETT2_MSD_ENABLE 0x02
+
+/* device_setup value to disable this mixer driver */
+#define SCARLETT2_DISABLE 0x04
+
+/* some gui mixers can't handle negative ctl values */
+#define SCARLETT2_VOLUME_BIAS 127
+
+/* mixer range from -80dB to +6dB in 0.5dB steps */
+#define SCARLETT2_MIXER_MIN_DB -80
+#define SCARLETT2_MIXER_BIAS (-SCARLETT2_MIXER_MIN_DB * 2)
+#define SCARLETT2_MIXER_MAX_DB 6
+#define SCARLETT2_MIXER_MAX_VALUE \
+       ((SCARLETT2_MIXER_MAX_DB - SCARLETT2_MIXER_MIN_DB) * 2)
+#define SCARLETT2_MIXER_VALUE_COUNT (SCARLETT2_MIXER_MAX_VALUE + 1)
+
+/* map from (dB + 80) * 2 to mixer value
+ * for dB in 0 .. 172: int(8192 * pow(10, ((dB - 160) / 2 / 20)))
+ */
+static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
+       0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2,
+       2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 8, 8,
+       9, 9, 10, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
+       23, 24, 25, 27, 29, 30, 32, 34, 36, 38, 41, 43, 46, 48, 51,
+       54, 57, 61, 65, 68, 73, 77, 81, 86, 91, 97, 103, 109, 115,
+       122, 129, 137, 145, 154, 163, 173, 183, 194, 205, 217, 230,
+       244, 259, 274, 290, 307, 326, 345, 365, 387, 410, 434, 460,
+       487, 516, 547, 579, 614, 650, 689, 730, 773, 819, 867, 919,
+       973, 1031, 1092, 1157, 1225, 1298, 1375, 1456, 1543, 1634,
+       1731, 1833, 1942, 2057, 2179, 2308, 2445, 2590, 2744, 2906,
+       3078, 3261, 3454, 3659, 3876, 4105, 4349, 4606, 4879, 5168,
+       5475, 5799, 6143, 6507, 6892, 7301, 7733, 8192, 8677, 9191,
+       9736, 10313, 10924, 11571, 12257, 12983, 13752, 14567, 15430,
+       16345
+};
+
+/* Maximum number of analogue outputs */
+#define SCARLETT2_ANALOGUE_MAX 10
+
+/* Maximum number of level and pad switches */
+#define SCARLETT2_LEVEL_SWITCH_MAX 2
+#define SCARLETT2_PAD_SWITCH_MAX 8
+#define SCARLETT2_AIR_SWITCH_MAX 8
+#define SCARLETT2_PHANTOM_SWITCH_MAX 2
+
+/* Maximum number of inputs to the mixer */
+#define SCARLETT2_INPUT_MIX_MAX 25
+
+/* Maximum number of outputs from the mixer */
+#define SCARLETT2_OUTPUT_MIX_MAX 12
+
+/* Maximum size of the data in the USB mux assignment message:
+ * 20 inputs, 20 outputs, 25 matrix inputs, 12 spare
+ */
+#define SCARLETT2_MUX_MAX 77
+
+/* Maximum number of meters (sum of output port counts) */
+#define SCARLETT2_MAX_METERS 65
+
+/* There are three different sets of configuration parameters across
+ * the devices
+ */
+enum {
+       SCARLETT2_CONFIG_SET_NO_MIXER = 0,
+       SCARLETT2_CONFIG_SET_GEN_2 = 1,
+       SCARLETT2_CONFIG_SET_GEN_3 = 2,
+       SCARLETT2_CONFIG_SET_CLARETT = 3,
+       SCARLETT2_CONFIG_SET_COUNT = 4
+};
+
+/* Hardware port types:
+ * - None (no input to mux)
+ * - Analogue I/O
+ * - S/PDIF I/O
+ * - ADAT I/O
+ * - Mixer I/O
+ * - PCM I/O
+ */
+enum {
+       SCARLETT2_PORT_TYPE_NONE     = 0,
+       SCARLETT2_PORT_TYPE_ANALOGUE = 1,
+       SCARLETT2_PORT_TYPE_SPDIF    = 2,
+       SCARLETT2_PORT_TYPE_ADAT     = 3,
+       SCARLETT2_PORT_TYPE_MIX      = 4,
+       SCARLETT2_PORT_TYPE_PCM      = 5,
+       SCARLETT2_PORT_TYPE_COUNT    = 6,
+};
+
+/* I/O count of each port type kept in struct scarlett2_ports */
+enum {
+       SCARLETT2_PORT_IN    = 0,
+       SCARLETT2_PORT_OUT   = 1,
+       SCARLETT2_PORT_DIRNS = 2,
+};
+
+/* Dim/Mute buttons on the 18i20 */
+enum {
+       SCARLETT2_BUTTON_MUTE    = 0,
+       SCARLETT2_BUTTON_DIM     = 1,
+       SCARLETT2_DIM_MUTE_COUNT = 2,
+};
+
+static const char *const scarlett2_dim_mute_names[SCARLETT2_DIM_MUTE_COUNT] = {
+       "Mute Playback Switch", "Dim Playback Switch"
+};
+
+/* Description of each hardware port type:
+ * - id: hardware ID of this port type
+ * - src_descr: printf format string for mux input selections
+ * - src_num_offset: added to channel number for the fprintf
+ * - dst_descr: printf format string for mixer controls
+ */
+struct scarlett2_port {
+       u16 id;
+       const char * const src_descr;
+       int src_num_offset;
+       const char * const dst_descr;
+};
+
+static const struct scarlett2_port scarlett2_ports[SCARLETT2_PORT_TYPE_COUNT] = {
+       [SCARLETT2_PORT_TYPE_NONE] = {
+               .id = 0x000,
+               .src_descr = "Off"
+       },
+       [SCARLETT2_PORT_TYPE_ANALOGUE] = {
+               .id = 0x080,
+               .src_descr = "Analogue %d",
+               .src_num_offset = 1,
+               .dst_descr = "Analogue Output %02d Playback"
+       },
+       [SCARLETT2_PORT_TYPE_SPDIF] = {
+               .id = 0x180,
+               .src_descr = "S/PDIF %d",
+               .src_num_offset = 1,
+               .dst_descr = "S/PDIF Output %d Playback"
+       },
+       [SCARLETT2_PORT_TYPE_ADAT] = {
+               .id = 0x200,
+               .src_descr = "ADAT %d",
+               .src_num_offset = 1,
+               .dst_descr = "ADAT Output %d Playback"
+       },
+       [SCARLETT2_PORT_TYPE_MIX] = {
+               .id = 0x300,
+               .src_descr = "Mix %c",
+               .src_num_offset = 'A',
+               .dst_descr = "Mixer Input %02d Capture"
+       },
+       [SCARLETT2_PORT_TYPE_PCM] = {
+               .id = 0x600,
+               .src_descr = "PCM %d",
+               .src_num_offset = 1,
+               .dst_descr = "PCM %02d Capture"
+       },
+};
+
+/* Number of mux tables: one for each band of sample rates
+ * (44.1/48kHz, 88.2/96kHz, and 176.4/176kHz)
+ */
+#define SCARLETT2_MUX_TABLES 3
+
+/* Maximum number of entries in a mux table */
+#define SCARLETT2_MAX_MUX_ENTRIES 10
+
+/* One entry within mux_assignment defines the port type and range of
+ * ports to add to the set_mux message. The end of the list is marked
+ * with count == 0.
+ */
+struct scarlett2_mux_entry {
+       u8 port_type;
+       u8 start;
+       u8 count;
+};
+
+struct scarlett2_device_info {
+       /* Gen 3 devices have an internal MSD mode switch that needs
+        * to be disabled in order to access the full functionality of
+        * the device.
+        */
+       u8 has_msd_mode;
+
+       /* which set of configuration parameters the device uses */
+       u8 config_set;
+
+       /* line out hw volume is sw controlled */
+       u8 line_out_hw_vol;
+
+       /* support for main/alt speaker switching */
+       u8 has_speaker_switching;
+
+       /* support for talkback microphone */
+       u8 has_talkback;
+
+       /* the number of analogue inputs with a software switchable
+        * level control that can be set to line or instrument
+        */
+       u8 level_input_count;
+
+       /* the first input with a level control (0-based) */
+       u8 level_input_first;
+
+       /* the number of analogue inputs with a software switchable
+        * 10dB pad control
+        */
+       u8 pad_input_count;
+
+       /* the number of analogue inputs with a software switchable
+        * "air" control
+        */
+       u8 air_input_count;
+
+       /* the number of phantom (48V) software switchable controls */
+       u8 phantom_count;
+
+       /* the number of inputs each phantom switch controls */
+       u8 inputs_per_phantom;
+
+       /* the number of direct monitor options
+        * (0 = none, 1 = mono only, 2 = mono/stereo)
+        */
+       u8 direct_monitor;
+
+       /* remap analogue outputs; 18i8 Gen 3 has "line 3/4" connected
+        * internally to the analogue 7/8 outputs
+        */
+       u8 line_out_remap_enable;
+       u8 line_out_remap[SCARLETT2_ANALOGUE_MAX];
+
+       /* additional description for the line out volume controls */
+       const char * const line_out_descrs[SCARLETT2_ANALOGUE_MAX];
+
+       /* number of sources/destinations of each port type */
+       const int port_count[SCARLETT2_PORT_TYPE_COUNT][SCARLETT2_PORT_DIRNS];
+
+       /* layout/order of the entries in the set_mux message */
+       struct scarlett2_mux_entry mux_assignment[SCARLETT2_MUX_TABLES]
+                                                [SCARLETT2_MAX_MUX_ENTRIES];
+};
+
+struct scarlett2_data {
+       struct usb_mixer_interface *mixer;
+       struct mutex usb_mutex; /* prevent sending concurrent USB requests */
+       struct mutex data_mutex; /* lock access to this data */
+       struct delayed_work work;
+       const struct scarlett2_device_info *info;
+       const char *series_name;
+       __u8 bInterfaceNumber;
+       __u8 bEndpointAddress;
+       __u16 wMaxPacketSize;
+       __u8 bInterval;
+       int num_mux_srcs;
+       int num_mux_dsts;
+       u16 scarlett2_seq;
+       u8 sync_updated;
+       u8 vol_updated;
+       u8 input_other_updated;
+       u8 monitor_other_updated;
+       u8 mux_updated;
+       u8 speaker_switching_switched;
+       u8 sync;
+       u8 master_vol;
+       u8 vol[SCARLETT2_ANALOGUE_MAX];
+       u8 vol_sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
+       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
+       u8 level_switch[SCARLETT2_LEVEL_SWITCH_MAX];
+       u8 pad_switch[SCARLETT2_PAD_SWITCH_MAX];
+       u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
+       u8 air_switch[SCARLETT2_AIR_SWITCH_MAX];
+       u8 phantom_switch[SCARLETT2_PHANTOM_SWITCH_MAX];
+       u8 phantom_persistence;
+       u8 direct_monitor_switch;
+       u8 speaker_switching_switch;
+       u8 talkback_switch;
+       u8 talkback_map[SCARLETT2_OUTPUT_MIX_MAX];
+       u8 msd_switch;
+       u8 standalone_switch;
+       struct snd_kcontrol *sync_ctl;
+       struct snd_kcontrol *master_vol_ctl;
+       struct snd_kcontrol *vol_ctls[SCARLETT2_ANALOGUE_MAX];
+       struct snd_kcontrol *sw_hw_ctls[SCARLETT2_ANALOGUE_MAX];
+       struct snd_kcontrol *mute_ctls[SCARLETT2_ANALOGUE_MAX];
+       struct snd_kcontrol *dim_mute_ctls[SCARLETT2_DIM_MUTE_COUNT];
+       struct snd_kcontrol *level_ctls[SCARLETT2_LEVEL_SWITCH_MAX];
+       struct snd_kcontrol *pad_ctls[SCARLETT2_PAD_SWITCH_MAX];
+       struct snd_kcontrol *air_ctls[SCARLETT2_AIR_SWITCH_MAX];
+       struct snd_kcontrol *phantom_ctls[SCARLETT2_PHANTOM_SWITCH_MAX];
+       struct snd_kcontrol *mux_ctls[SCARLETT2_MUX_MAX];
+       struct snd_kcontrol *direct_monitor_ctl;
+       struct snd_kcontrol *speaker_switching_ctl;
+       struct snd_kcontrol *talkback_ctl;
+       u8 mux[SCARLETT2_MUX_MAX];
+       u8 mix[SCARLETT2_INPUT_MIX_MAX * SCARLETT2_OUTPUT_MIX_MAX];
+};
+
+/*** Model-specific data ***/
+
+static const struct scarlett2_device_info s6i6_gen2_info = {
+       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
+       .level_input_count = 2,
+       .pad_input_count = 2,
+
+       .line_out_descrs = {
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  4,  4 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = {  6,  6 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info s18i8_gen2_info = {
+       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
+       .level_input_count = 2,
+       .pad_input_count = 4,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  6 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 18 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 10 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  4 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info s18i20_gen2_info = {
+       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
+       .line_out_hw_vol = 1,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               NULL,
+               NULL,
+               NULL,
+               NULL,
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8, 10 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 18 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,     0,  8 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,     0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 10 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  6 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info solo_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
+       .level_input_count = 1,
+       .level_input_first = 1,
+       .air_input_count = 1,
+       .phantom_count = 1,
+       .inputs_per_phantom = 1,
+       .direct_monitor = 1,
+};
+
+static const struct scarlett2_device_info s2i2_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
+       .level_input_count = 2,
+       .air_input_count = 2,
+       .phantom_count = 1,
+       .inputs_per_phantom = 2,
+       .direct_monitor = 2,
+};
+
+static const struct scarlett2_device_info s4i4_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
+       .level_input_count = 2,
+       .pad_input_count = 2,
+       .air_input_count = 2,
+       .phantom_count = 1,
+       .inputs_per_phantom = 2,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               "Headphones L",
+               "Headphones R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = { 1, 0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = { 4, 4 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 6, 8 },
+               [SCARLETT2_PORT_TYPE_PCM]      = { 4, 6 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info s8i6_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
+       .level_input_count = 2,
+       .pad_input_count = 2,
+       .air_input_count = 2,
+       .phantom_count = 1,
+       .inputs_per_phantom = 2,
+
+       .line_out_descrs = {
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = { 1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = { 6,  4 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = { 2,  2 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 8,  8 },
+               [SCARLETT2_PORT_TYPE_PCM]      = { 6, 10 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info s18i8_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
+       .line_out_hw_vol = 1,
+       .has_speaker_switching = 1,
+       .level_input_count = 2,
+       .pad_input_count = 4,
+       .air_input_count = 4,
+       .phantom_count = 2,
+       .inputs_per_phantom = 2,
+
+       .line_out_remap_enable = 1,
+       .line_out_remap = { 0, 1, 6, 7, 2, 3, 4, 5 },
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               "Alt Monitor L",
+               "Alt Monitor R",
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  8 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 20 },
+               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 20 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
+               { SCARLETT2_PORT_TYPE_PCM,      12,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_PCM,      10,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
+               { 0,                             0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
+               { SCARLETT2_PORT_TYPE_PCM,      12,  4 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_PCM,      10,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
+               { 0,                             0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
+               { 0,                             0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info s18i20_gen3_info = {
+       .has_msd_mode = 1,
+       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
+       .line_out_hw_vol = 1,
+       .has_speaker_switching = 1,
+       .has_talkback = 1,
+       .level_input_count = 2,
+       .pad_input_count = 8,
+       .air_input_count = 8,
+       .phantom_count = 2,
+       .inputs_per_phantom = 4,
+
+       .line_out_descrs = {
+               "Monitor 1 L",
+               "Monitor 1 R",
+               "Monitor 2 L",
+               "Monitor 2 R",
+               NULL,
+               NULL,
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  9, 10 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 12, 25 },
+               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 20 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,       0,  8 },
+               { SCARLETT2_PORT_TYPE_PCM,      10, 10 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,      0,  8 },
+               { SCARLETT2_PORT_TYPE_PCM,       8,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,       0, 25 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 12 },
+               { 0,                             0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,       0,  8 },
+               { SCARLETT2_PORT_TYPE_PCM,      10,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,      0,  8 },
+               { SCARLETT2_PORT_TYPE_PCM,       8,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,       0, 25 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
+               { 0,                             0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
+               { SCARLETT2_PORT_TYPE_NONE,      0, 24 },
+               { 0,                             0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info clarett_2pre_info = {
+       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
+       .line_out_hw_vol = 1,
+       .level_input_count = 2,
+       .air_input_count = 2,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               "Headphones L",
+               "Headphones R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  2,  4 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  0 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = {  4, 12 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0,  2 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 26 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info clarett_4pre_info = {
+       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
+       .line_out_hw_vol = 1,
+       .level_input_count = 2,
+       .air_input_count = 4,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  6 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 18 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 24 },
+               { 0,                            0,  0 },
+       } },
+};
+
+static const struct scarlett2_device_info clarett_8pre_info = {
+       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
+       .line_out_hw_vol = 1,
+       .level_input_count = 2,
+       .air_input_count = 8,
+
+       .line_out_descrs = {
+               "Monitor L",
+               "Monitor R",
+               NULL,
+               NULL,
+               NULL,
+               NULL,
+               "Headphones 1 L",
+               "Headphones 1 R",
+               "Headphones 2 L",
+               "Headphones 2 R",
+       },
+
+       .port_count = {
+               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8, 10 },
+               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
+               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
+               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
+               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 18 },
+       },
+
+       .mux_assignment = { {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,     0,  8 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_ADAT,     0,  4 },
+               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
+               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
+               { 0,                            0,  0 },
+       }, {
+               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
+               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
+               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
+               { SCARLETT2_PORT_TYPE_NONE,     0, 22 },
+               { 0,                            0,  0 },
+       } },
+};
+
+struct scarlett2_device_entry {
+       const u32 usb_id; /* USB device identifier */
+       const struct scarlett2_device_info *info;
+       const char *series_name;
+};
+
+static const struct scarlett2_device_entry scarlett2_devices[] = {
+       /* Supported Gen 2 devices */
+       { USB_ID(0x1235, 0x8203), &s6i6_gen2_info, "Scarlett Gen 2" },
+       { USB_ID(0x1235, 0x8204), &s18i8_gen2_info, "Scarlett Gen 2" },
+       { USB_ID(0x1235, 0x8201), &s18i20_gen2_info, "Scarlett Gen 2" },
+
+       /* Supported Gen 3 devices */
+       { USB_ID(0x1235, 0x8211), &solo_gen3_info, "Scarlett Gen 3" },
+       { USB_ID(0x1235, 0x8210), &s2i2_gen3_info, "Scarlett Gen 3" },
+       { USB_ID(0x1235, 0x8212), &s4i4_gen3_info, "Scarlett Gen 3" },
+       { USB_ID(0x1235, 0x8213), &s8i6_gen3_info, "Scarlett Gen 3" },
+       { USB_ID(0x1235, 0x8214), &s18i8_gen3_info, "Scarlett Gen 3" },
+       { USB_ID(0x1235, 0x8215), &s18i20_gen3_info, "Scarlett Gen 3" },
+
+       /* Supported Clarett USB/Clarett+ devices */
+       { USB_ID(0x1235, 0x8206), &clarett_2pre_info, "Clarett USB" },
+       { USB_ID(0x1235, 0x8207), &clarett_4pre_info, "Clarett USB" },
+       { USB_ID(0x1235, 0x8208), &clarett_8pre_info, "Clarett USB" },
+       { USB_ID(0x1235, 0x820a), &clarett_2pre_info, "Clarett+" },
+       { USB_ID(0x1235, 0x820b), &clarett_4pre_info, "Clarett+" },
+       { USB_ID(0x1235, 0x820c), &clarett_8pre_info, "Clarett+" },
+
+       /* End of list */
+       { 0, NULL },
+};
+
+/* get the starting port index number for a given port type/direction */
+static int scarlett2_get_port_start_num(
+       const int port_count[][SCARLETT2_PORT_DIRNS],
+       int direction, int port_type)
+{
+       int i, num = 0;
+
+       for (i = 0; i < port_type; i++)
+               num += port_count[i][direction];
+
+       return num;
+}
+
+/*** USB Interactions ***/
+
+/* Notifications from the interface */
+#define SCARLETT2_USB_NOTIFY_SYNC          0x00000008
+#define SCARLETT2_USB_NOTIFY_DIM_MUTE      0x00200000
+#define SCARLETT2_USB_NOTIFY_MONITOR       0x00400000
+#define SCARLETT2_USB_NOTIFY_INPUT_OTHER   0x00800000
+#define SCARLETT2_USB_NOTIFY_MONITOR_OTHER 0x01000000
+
+/* Commands for sending/receiving requests/responses */
+#define SCARLETT2_USB_CMD_INIT 0
+#define SCARLETT2_USB_CMD_REQ  2
+#define SCARLETT2_USB_CMD_RESP 3
+
+#define SCARLETT2_USB_INIT_1    0x00000000
+#define SCARLETT2_USB_INIT_2    0x00000002
+#define SCARLETT2_USB_GET_METER 0x00001001
+#define SCARLETT2_USB_GET_MIX   0x00002001
+#define SCARLETT2_USB_SET_MIX   0x00002002
+#define SCARLETT2_USB_GET_MUX   0x00003001
+#define SCARLETT2_USB_SET_MUX   0x00003002
+#define SCARLETT2_USB_GET_SYNC  0x00006004
+#define SCARLETT2_USB_GET_DATA  0x00800000
+#define SCARLETT2_USB_SET_DATA  0x00800001
+#define SCARLETT2_USB_DATA_CMD  0x00800002
+
+#define SCARLETT2_USB_CONFIG_SAVE 6
+
+#define SCARLETT2_USB_VOLUME_STATUS_OFFSET 0x31
+#define SCARLETT2_USB_METER_LEVELS_GET_MAGIC 1
+
+/* volume status is read together (matches scarlett2_config_items[1]) */
+struct scarlett2_usb_volume_status {
+       /* dim/mute buttons */
+       u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
+
+       u8 pad1;
+
+       /* software volume setting */
+       s16 sw_vol[SCARLETT2_ANALOGUE_MAX];
+
+       /* actual volume of output inc. dim (-18dB) */
+       s16 hw_vol[SCARLETT2_ANALOGUE_MAX];
+
+       /* internal mute buttons */
+       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
+
+       /* sw (0) or hw (1) controlled */
+       u8 sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
+
+       u8 pad3[6];
+
+       /* front panel volume knob */
+       s16 master_vol;
+} __packed;
+
+/* Configuration parameters that can be read and written */
+enum {
+       SCARLETT2_CONFIG_DIM_MUTE = 0,
+       SCARLETT2_CONFIG_LINE_OUT_VOLUME = 1,
+       SCARLETT2_CONFIG_MUTE_SWITCH = 2,
+       SCARLETT2_CONFIG_SW_HW_SWITCH = 3,
+       SCARLETT2_CONFIG_LEVEL_SWITCH = 4,
+       SCARLETT2_CONFIG_PAD_SWITCH = 5,
+       SCARLETT2_CONFIG_MSD_SWITCH = 6,
+       SCARLETT2_CONFIG_AIR_SWITCH = 7,
+       SCARLETT2_CONFIG_STANDALONE_SWITCH = 8,
+       SCARLETT2_CONFIG_PHANTOM_SWITCH = 9,
+       SCARLETT2_CONFIG_PHANTOM_PERSISTENCE = 10,
+       SCARLETT2_CONFIG_DIRECT_MONITOR = 11,
+       SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH = 12,
+       SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE = 13,
+       SCARLETT2_CONFIG_TALKBACK_MAP = 14,
+       SCARLETT2_CONFIG_COUNT = 15
+};
+
+/* Location, size, and activation command number for the configuration
+ * parameters. Size is in bits and may be 1, 8, or 16.
+ */
+struct scarlett2_config {
+       u8 offset;
+       u8 size;
+       u8 activate;
+};
+
+static const struct scarlett2_config
+       scarlett2_config_items[SCARLETT2_CONFIG_SET_COUNT]
+                             [SCARLETT2_CONFIG_COUNT] =
+
+/* Devices without a mixer (Gen 3 Solo and 2i2) */
+{ {
+       [SCARLETT2_CONFIG_MSD_SWITCH] = {
+               .offset = 0x04, .size = 8, .activate = 6 },
+
+       [SCARLETT2_CONFIG_PHANTOM_PERSISTENCE] = {
+               .offset = 0x05, .size = 8, .activate = 6 },
+
+       [SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
+               .offset = 0x06, .size = 8, .activate = 3 },
+
+       [SCARLETT2_CONFIG_DIRECT_MONITOR] = {
+               .offset = 0x07, .size = 8, .activate = 4 },
+
+       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
+               .offset = 0x08, .size = 1, .activate = 7 },
+
+       [SCARLETT2_CONFIG_AIR_SWITCH] = {
+               .offset = 0x09, .size = 1, .activate = 8 },
+
+/* Gen 2 devices: 6i6, 18i8, 18i20 */
+}, {
+       [SCARLETT2_CONFIG_DIM_MUTE] = {
+               .offset = 0x31, .size = 8, .activate = 2 },
+
+       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
+               .offset = 0x34, .size = 16, .activate = 1 },
+
+       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
+               .offset = 0x5c, .size = 8, .activate = 1 },
+
+       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
+               .offset = 0x66, .size = 8, .activate = 3 },
+
+       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
+               .offset = 0x7c, .size = 8, .activate = 7 },
+
+       [SCARLETT2_CONFIG_PAD_SWITCH] = {
+               .offset = 0x84, .size = 8, .activate = 8 },
+
+       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
+               .offset = 0x8d, .size = 8, .activate = 6 },
+
+/* Gen 3 devices: 4i4, 8i6, 18i8, 18i20 */
+}, {
+       [SCARLETT2_CONFIG_DIM_MUTE] = {
+               .offset = 0x31, .size = 8, .activate = 2 },
+
+       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
+               .offset = 0x34, .size = 16, .activate = 1 },
+
+       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
+               .offset = 0x5c, .size = 8, .activate = 1 },
+
+       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
+               .offset = 0x66, .size = 8, .activate = 3 },
+
+       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
+               .offset = 0x7c, .size = 8, .activate = 7 },
+
+       [SCARLETT2_CONFIG_PAD_SWITCH] = {
+               .offset = 0x84, .size = 8, .activate = 8 },
+
+       [SCARLETT2_CONFIG_AIR_SWITCH] = {
+               .offset = 0x8c, .size = 8, .activate = 8 },
+
+       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
+               .offset = 0x95, .size = 8, .activate = 6 },
+
+       [SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
+               .offset = 0x9c, .size = 1, .activate = 8 },
+
+       [SCARLETT2_CONFIG_MSD_SWITCH] = {
+               .offset = 0x9d, .size = 8, .activate = 6 },
+
+       [SCARLETT2_CONFIG_PHANTOM_PERSISTENCE] = {
+               .offset = 0x9e, .size = 8, .activate = 6 },
+
+       [SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH] = {
+               .offset = 0x9f, .size = 1, .activate = 10 },
+
+       [SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE] = {
+               .offset = 0xa0, .size = 1, .activate = 10 },
+
+       [SCARLETT2_CONFIG_TALKBACK_MAP] = {
+               .offset = 0xb0, .size = 16, .activate = 10 },
+
+/* Clarett USB and Clarett+ devices: 2Pre, 4Pre, 8Pre */
+}, {
+       [SCARLETT2_CONFIG_DIM_MUTE] = {
+               .offset = 0x31, .size = 8, .activate = 2 },
+
+       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
+               .offset = 0x34, .size = 16, .activate = 1 },
+
+       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
+               .offset = 0x5c, .size = 8, .activate = 1 },
+
+       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
+               .offset = 0x66, .size = 8, .activate = 3 },
+
+       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
+               .offset = 0x7c, .size = 8, .activate = 7 },
+
+       [SCARLETT2_CONFIG_AIR_SWITCH] = {
+               .offset = 0x95, .size = 8, .activate = 8 },
+
+       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
+               .offset = 0x8d, .size = 8, .activate = 6 },
+} };
+
+/* proprietary request/response format */
+struct scarlett2_usb_packet {
+       __le32 cmd;
+       __le16 size;
+       __le16 seq;
+       __le32 error;
+       __le32 pad;
+       u8 data[];
+};
+
+static void scarlett2_fill_request_header(struct scarlett2_data *private,
+                                         struct scarlett2_usb_packet *req,
+                                         u32 cmd, u16 req_size)
+{
+       /* sequence must go up by 1 for each request */
+       u16 seq = private->scarlett2_seq++;
+
+       req->cmd = cpu_to_le32(cmd);
+       req->size = cpu_to_le16(req_size);
+       req->seq = cpu_to_le16(seq);
+       req->error = 0;
+       req->pad = 0;
+}
+
+static int scarlett2_usb_tx(struct usb_device *dev, int interface,
+                           void *buf, u16 size)
+{
+       return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
+                       SCARLETT2_USB_CMD_REQ,
+                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+                       0, interface, buf, size);
+}
+
+static int scarlett2_usb_rx(struct usb_device *dev, int interface,
+                           u32 usb_req, void *buf, u16 size)
+{
+       return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+                       usb_req,
+                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+                       0, interface, buf, size);
+}
+
+/* Send a proprietary format request to the Scarlett interface */
+static int scarlett2_usb(
+       struct usb_mixer_interface *mixer, u32 cmd,
+       void *req_data, u16 req_size, void *resp_data, u16 resp_size)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       struct usb_device *dev = mixer->chip->dev;
+       struct scarlett2_usb_packet *req, *resp = NULL;
+       size_t req_buf_size = struct_size(req, data, req_size);
+       size_t resp_buf_size = struct_size(resp, data, resp_size);
+       int err;
+
+       req = kmalloc(req_buf_size, GFP_KERNEL);
+       if (!req) {
+               err = -ENOMEM;
+               goto error;
+       }
+
+       resp = kmalloc(resp_buf_size, GFP_KERNEL);
+       if (!resp) {
+               err = -ENOMEM;
+               goto error;
+       }
+
+       mutex_lock(&private->usb_mutex);
+
+       /* build request message and send it */
+
+       scarlett2_fill_request_header(private, req, cmd, req_size);
+
+       if (req_size)
+               memcpy(req->data, req_data, req_size);
+
+       err = scarlett2_usb_tx(dev, private->bInterfaceNumber,
+                              req, req_buf_size);
+
+       if (err != req_buf_size) {
+               usb_audio_err(
+                       mixer->chip,
+                       "%s USB request result cmd %x was %d\n",
+                       private->series_name, cmd, err);
+               err = -EINVAL;
+               goto unlock;
+       }
+
+       /* send a second message to get the response */
+
+       err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
+                              SCARLETT2_USB_CMD_RESP,
+                              resp, resp_buf_size);
+
+       /* validate the response */
+
+       if (err != resp_buf_size) {
+               usb_audio_err(
+                       mixer->chip,
+                       "%s USB response result cmd %x was %d expected %zu\n",
+                       private->series_name, cmd, err, resp_buf_size);
+               err = -EINVAL;
+               goto unlock;
+       }
+
+       /* cmd/seq/size should match except when initialising
+        * seq sent = 1, response = 0
+        */
+       if (resp->cmd != req->cmd ||
+           (resp->seq != req->seq &&
+               (le16_to_cpu(req->seq) != 1 || resp->seq != 0)) ||
+           resp_size != le16_to_cpu(resp->size) ||
+           resp->error ||
+           resp->pad) {
+               usb_audio_err(
+                       mixer->chip,
+                       "%s USB invalid response; "
+                          "cmd tx/rx %d/%d seq %d/%d size %d/%d "
+                          "error %d pad %d\n",
+                       private->series_name,
+                       le32_to_cpu(req->cmd), le32_to_cpu(resp->cmd),
+                       le16_to_cpu(req->seq), le16_to_cpu(resp->seq),
+                       resp_size, le16_to_cpu(resp->size),
+                       le32_to_cpu(resp->error),
+                       le32_to_cpu(resp->pad));
+               err = -EINVAL;
+               goto unlock;
+       }
+
+       if (resp_data && resp_size > 0)
+               memcpy(resp_data, resp->data, resp_size);
+
+unlock:
+       mutex_unlock(&private->usb_mutex);
+error:
+       kfree(req);
+       kfree(resp);
+       return err;
+}
+
+/* Send a USB message to get data; result placed in *buf */
+static int scarlett2_usb_get(
+       struct usb_mixer_interface *mixer,
+       int offset, void *buf, int size)
+{
+       struct {
+               __le32 offset;
+               __le32 size;
+       } __packed req;
+
+       req.offset = cpu_to_le32(offset);
+       req.size = cpu_to_le32(size);
+       return scarlett2_usb(mixer, SCARLETT2_USB_GET_DATA,
+                            &req, sizeof(req), buf, size);
+}
+
+/* Send a USB message to get configuration parameters; result placed in *buf */
+static int scarlett2_usb_get_config(
+       struct usb_mixer_interface *mixer,
+       int config_item_num, int count, void *buf)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const struct scarlett2_config *config_item =
+               &scarlett2_config_items[info->config_set][config_item_num];
+       int size, err, i;
+       u8 *buf_8;
+       u8 value;
+
+       /* For byte-sized parameters, retrieve directly into buf */
+       if (config_item->size >= 8) {
+               size = config_item->size / 8 * count;
+               err = scarlett2_usb_get(mixer, config_item->offset, buf, size);
+               if (err < 0)
+                       return err;
+               if (size == 2) {
+                       u16 *buf_16 = buf;
+
+                       for (i = 0; i < count; i++, buf_16++)
+                               *buf_16 = le16_to_cpu(*(__le16 *)buf_16);
+               }
+               return 0;
+       }
+
+       /* For bit-sized parameters, retrieve into value */
+       err = scarlett2_usb_get(mixer, config_item->offset, &value, 1);
+       if (err < 0)
+               return err;
+
+       /* then unpack from value into buf[] */
+       buf_8 = buf;
+       for (i = 0; i < 8 && i < count; i++, value >>= 1)
+               *buf_8++ = value & 1;
+
+       return 0;
+}
+
+/* Send SCARLETT2_USB_DATA_CMD SCARLETT2_USB_CONFIG_SAVE */
+static void scarlett2_config_save(struct usb_mixer_interface *mixer)
+{
+       __le32 req = cpu_to_le32(SCARLETT2_USB_CONFIG_SAVE);
+
+       scarlett2_usb(mixer, SCARLETT2_USB_DATA_CMD,
+                     &req, sizeof(u32),
+                     NULL, 0);
+}
+
+/* Delayed work to save config */
+static void scarlett2_config_save_work(struct work_struct *work)
+{
+       struct scarlett2_data *private =
+               container_of(work, struct scarlett2_data, work.work);
+
+       scarlett2_config_save(private->mixer);
+}
+
+/* Send a USB message to set a SCARLETT2_CONFIG_* parameter */
+static int scarlett2_usb_set_config(
+       struct usb_mixer_interface *mixer,
+       int config_item_num, int index, int value)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const struct scarlett2_config *config_item =
+              &scarlett2_config_items[info->config_set][config_item_num];
+       struct {
+               __le32 offset;
+               __le32 bytes;
+               __le32 value;
+       } __packed req;
+       __le32 req2;
+       int offset, size;
+       int err;
+
+       /* Cancel any pending NVRAM save */
+       cancel_delayed_work_sync(&private->work);
+
+       /* Convert config_item->size in bits to size in bytes and
+        * calculate offset
+        */
+       if (config_item->size >= 8) {
+               size = config_item->size / 8;
+               offset = config_item->offset + index * size;
+
+       /* If updating a bit, retrieve the old value, set/clear the
+        * bit as needed, and update value
+        */
+       } else {
+               u8 tmp;
+
+               size = 1;
+               offset = config_item->offset;
+
+               scarlett2_usb_get(mixer, offset, &tmp, 1);
+               if (value)
+                       tmp |= (1 << index);
+               else
+                       tmp &= ~(1 << index);
+
+               value = tmp;
+       }
+
+       /* Send the configuration parameter data */
+       req.offset = cpu_to_le32(offset);
+       req.bytes = cpu_to_le32(size);
+       req.value = cpu_to_le32(value);
+       err = scarlett2_usb(mixer, SCARLETT2_USB_SET_DATA,
+                           &req, sizeof(u32) * 2 + size,
+                           NULL, 0);
+       if (err < 0)
+               return err;
+
+       /* Activate the change */
+       req2 = cpu_to_le32(config_item->activate);
+       err = scarlett2_usb(mixer, SCARLETT2_USB_DATA_CMD,
+                           &req2, sizeof(req2), NULL, 0);
+       if (err < 0)
+               return err;
+
+       /* Schedule the change to be written to NVRAM */
+       if (config_item->activate != SCARLETT2_USB_CONFIG_SAVE)
+               schedule_delayed_work(&private->work, msecs_to_jiffies(2000));
+
+       return 0;
+}
+
+/* Send a USB message to get sync status; result placed in *sync */
+static int scarlett2_usb_get_sync_status(
+       struct usb_mixer_interface *mixer,
+       u8 *sync)
+{
+       __le32 data;
+       int err;
+
+       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_SYNC,
+                           NULL, 0, &data, sizeof(data));
+       if (err < 0)
+               return err;
+
+       *sync = !!data;
+       return 0;
+}
+
+/* Send a USB message to get volume status; result placed in *buf */
+static int scarlett2_usb_get_volume_status(
+       struct usb_mixer_interface *mixer,
+       struct scarlett2_usb_volume_status *buf)
+{
+       return scarlett2_usb_get(mixer, SCARLETT2_USB_VOLUME_STATUS_OFFSET,
+                                buf, sizeof(*buf));
+}
+
+/* Send a USB message to get the volumes for all inputs of one mix
+ * and put the values into private->mix[]
+ */
+static int scarlett2_usb_get_mix(struct usb_mixer_interface *mixer,
+                                int mix_num)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       int num_mixer_in =
+               info->port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
+       int err, i, j, k;
+
+       struct {
+               __le16 mix_num;
+               __le16 count;
+       } __packed req;
+
+       __le16 data[SCARLETT2_INPUT_MIX_MAX];
+
+       req.mix_num = cpu_to_le16(mix_num);
+       req.count = cpu_to_le16(num_mixer_in);
+
+       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_MIX,
+                           &req, sizeof(req),
+                           data, num_mixer_in * sizeof(u16));
+       if (err < 0)
+               return err;
+
+       for (i = 0, j = mix_num * num_mixer_in; i < num_mixer_in; i++, j++) {
+               u16 mixer_value = le16_to_cpu(data[i]);
+
+               for (k = 0; k < SCARLETT2_MIXER_VALUE_COUNT; k++)
+                       if (scarlett2_mixer_values[k] >= mixer_value)
+                               break;
+               if (k == SCARLETT2_MIXER_VALUE_COUNT)
+                       k = SCARLETT2_MIXER_MAX_VALUE;
+               private->mix[j] = k;
+       }
+
+       return 0;
+}
+
+/* Send a USB message to set the volumes for all inputs of one mix
+ * (values obtained from private->mix[])
+ */
+static int scarlett2_usb_set_mix(struct usb_mixer_interface *mixer,
+                                int mix_num)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       struct {
+               __le16 mix_num;
+               __le16 data[SCARLETT2_INPUT_MIX_MAX];
+       } __packed req;
+
+       int i, j;
+       int num_mixer_in =
+               info->port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
+
+       req.mix_num = cpu_to_le16(mix_num);
+
+       for (i = 0, j = mix_num * num_mixer_in; i < num_mixer_in; i++, j++)
+               req.data[i] = cpu_to_le16(
+                       scarlett2_mixer_values[private->mix[j]]
+               );
+
+       return scarlett2_usb(mixer, SCARLETT2_USB_SET_MIX,
+                            &req, (num_mixer_in + 1) * sizeof(u16),
+                            NULL, 0);
+}
+
+/* Convert a port number index (per info->port_count) to a hardware ID */
+static u32 scarlett2_mux_src_num_to_id(
+       const int port_count[][SCARLETT2_PORT_DIRNS], int num)
+{
+       int port_type;
+
+       for (port_type = 0;
+            port_type < SCARLETT2_PORT_TYPE_COUNT;
+            port_type++) {
+               if (num < port_count[port_type][SCARLETT2_PORT_IN])
+                       return scarlett2_ports[port_type].id | num;
+               num -= port_count[port_type][SCARLETT2_PORT_IN];
+       }
+
+       /* Oops */
+       return 0;
+}
+
+/* Convert a hardware ID to a port number index */
+static u32 scarlett2_mux_id_to_num(
+       const int port_count[][SCARLETT2_PORT_DIRNS], int direction, u32 id)
+{
+       int port_type;
+       int port_num = 0;
+
+       for (port_type = 0;
+            port_type < SCARLETT2_PORT_TYPE_COUNT;
+            port_type++) {
+               int base = scarlett2_ports[port_type].id;
+               int count = port_count[port_type][direction];
+
+               if (id >= base && id < base + count)
+                       return port_num + id - base;
+               port_num += count;
+       }
+
+       /* Oops */
+       return -1;
+}
+
+/* Convert one mux entry from the interface and load into private->mux[] */
+static void scarlett2_usb_populate_mux(struct scarlett2_data *private,
+                                      u32 mux_entry)
+{
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+
+       int dst_idx, src_idx;
+
+       dst_idx = scarlett2_mux_id_to_num(port_count, SCARLETT2_PORT_OUT,
+                                         mux_entry & 0xFFF);
+       if (dst_idx < 0)
+               return;
+
+       if (dst_idx >= private->num_mux_dsts) {
+               usb_audio_err(private->mixer->chip,
+                       "BUG: scarlett2_mux_id_to_num(%06x, OUT): %d >= %d",
+                       mux_entry, dst_idx, private->num_mux_dsts);
+               return;
+       }
+
+       src_idx = scarlett2_mux_id_to_num(port_count, SCARLETT2_PORT_IN,
+                                         mux_entry >> 12);
+       if (src_idx < 0)
+               return;
+
+       if (src_idx >= private->num_mux_srcs) {
+               usb_audio_err(private->mixer->chip,
+                       "BUG: scarlett2_mux_id_to_num(%06x, IN): %d >= %d",
+                       mux_entry, src_idx, private->num_mux_srcs);
+               return;
+       }
+
+       private->mux[dst_idx] = src_idx;
+}
+
+/* Send USB message to get mux inputs and then populate private->mux[] */
+static int scarlett2_usb_get_mux(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       int count = private->num_mux_dsts;
+       int err, i;
+
+       struct {
+               __le16 num;
+               __le16 count;
+       } __packed req;
+
+       __le32 data[SCARLETT2_MUX_MAX];
+
+       private->mux_updated = 0;
+
+       req.num = 0;
+       req.count = cpu_to_le16(count);
+
+       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_MUX,
+                           &req, sizeof(req),
+                           data, count * sizeof(u32));
+       if (err < 0)
+               return err;
+
+       for (i = 0; i < count; i++)
+               scarlett2_usb_populate_mux(private, le32_to_cpu(data[i]));
+
+       return 0;
+}
+
+/* Send USB messages to set mux inputs */
+static int scarlett2_usb_set_mux(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int table;
+
+       struct {
+               __le16 pad;
+               __le16 num;
+               __le32 data[SCARLETT2_MUX_MAX];
+       } __packed req;
+
+       req.pad = 0;
+
+       /* set mux settings for each rate */
+       for (table = 0; table < SCARLETT2_MUX_TABLES; table++) {
+               const struct scarlett2_mux_entry *entry;
+
+               /* i counts over the output array */
+               int i = 0, err;
+
+               req.num = cpu_to_le16(table);
+
+               /* loop through each entry */
+               for (entry = info->mux_assignment[table];
+                    entry->count;
+                    entry++) {
+                       int j;
+                       int port_type = entry->port_type;
+                       int port_idx = entry->start;
+                       int mux_idx = scarlett2_get_port_start_num(port_count,
+                               SCARLETT2_PORT_OUT, port_type) + port_idx;
+                       int dst_id = scarlett2_ports[port_type].id + port_idx;
+
+                       /* Empty slots */
+                       if (!dst_id) {
+                               for (j = 0; j < entry->count; j++)
+                                       req.data[i++] = 0;
+                               continue;
+                       }
+
+                       /* Non-empty mux slots use the lower 12 bits
+                        * for the destination and next 12 bits for
+                        * the source
+                        */
+                       for (j = 0; j < entry->count; j++) {
+                               int src_id = scarlett2_mux_src_num_to_id(
+                                       port_count, private->mux[mux_idx++]);
+                               req.data[i++] = cpu_to_le32(dst_id |
+                                                           src_id << 12);
+                               dst_id++;
+                       }
+               }
+
+               err = scarlett2_usb(mixer, SCARLETT2_USB_SET_MUX,
+                                   &req, (i + 1) * sizeof(u32),
+                                   NULL, 0);
+               if (err < 0)
+                       return err;
+       }
+
+       return 0;
+}
+
+/* Send USB message to get meter levels */
+static int scarlett2_usb_get_meter_levels(struct usb_mixer_interface *mixer,
+                                         u16 num_meters, u16 *levels)
+{
+       struct {
+               __le16 pad;
+               __le16 num_meters;
+               __le32 magic;
+       } __packed req;
+       u32 resp[SCARLETT2_MAX_METERS];
+       int i, err;
+
+       req.pad = 0;
+       req.num_meters = cpu_to_le16(num_meters);
+       req.magic = cpu_to_le32(SCARLETT2_USB_METER_LEVELS_GET_MAGIC);
+       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_METER,
+                           &req, sizeof(req), resp, num_meters * sizeof(u32));
+       if (err < 0)
+               return err;
+
+       /* copy, convert to u16 */
+       for (i = 0; i < num_meters; i++)
+               levels[i] = resp[i];
+
+       return 0;
+}
+
+/*** Control Functions ***/
+
+/* helper function to create a new control */
+static int scarlett2_add_new_ctl(struct usb_mixer_interface *mixer,
+                                const struct snd_kcontrol_new *ncontrol,
+                                int index, int channels, const char *name,
+                                struct snd_kcontrol **kctl_return)
+{
+       struct snd_kcontrol *kctl;
+       struct usb_mixer_elem_info *elem;
+       int err;
+
+       elem = kzalloc(sizeof(*elem), GFP_KERNEL);
+       if (!elem)
+               return -ENOMEM;
+
+       /* We set USB_MIXER_BESPOKEN type, so that the core USB mixer code
+        * ignores them for resume and other operations.
+        * Also, the head.id field is set to 0, as we don't use this field.
+        */
+       elem->head.mixer = mixer;
+       elem->control = index;
+       elem->head.id = 0;
+       elem->channels = channels;
+       elem->val_type = USB_MIXER_BESPOKEN;
+
+       kctl = snd_ctl_new1(ncontrol, elem);
+       if (!kctl) {
+               kfree(elem);
+               return -ENOMEM;
+       }
+       kctl->private_free = snd_usb_mixer_elem_free;
+
+       strscpy(kctl->id.name, name, sizeof(kctl->id.name));
+
+       err = snd_usb_mixer_add_control(&elem->head, kctl);
+       if (err < 0)
+               return err;
+
+       if (kctl_return)
+               *kctl_return = kctl;
+
+       return 0;
+}
+
+/*** Sync Control ***/
+
+/* Update sync control after receiving notification that the status
+ * has changed
+ */
+static int scarlett2_update_sync(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       private->sync_updated = 0;
+       return scarlett2_usb_get_sync_status(mixer, &private->sync);
+}
+
+static int scarlett2_sync_ctl_info(struct snd_kcontrol *kctl,
+                                  struct snd_ctl_elem_info *uinfo)
+{
+       static const char *texts[2] = {
+               "Unlocked", "Locked"
+       };
+       return snd_ctl_enum_info(uinfo, 1, 2, texts);
+}
+
+static int scarlett2_sync_ctl_get(struct snd_kcontrol *kctl,
+                                 struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->sync_updated)
+               scarlett2_update_sync(mixer);
+       ucontrol->value.enumerated.item[0] = private->sync;
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static const struct snd_kcontrol_new scarlett2_sync_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .access = SNDRV_CTL_ELEM_ACCESS_READ,
+       .name = "",
+       .info = scarlett2_sync_ctl_info,
+       .get  = scarlett2_sync_ctl_get
+};
+
+static int scarlett2_add_sync_ctl(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       /* devices without a mixer also don't support reporting sync status */
+       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
+               return 0;
+
+       return scarlett2_add_new_ctl(mixer, &scarlett2_sync_ctl,
+                                    0, 1, "Sync Status", &private->sync_ctl);
+}
+
+/*** Analogue Line Out Volume Controls ***/
+
+/* Update hardware volume controls after receiving notification that
+ * they have changed
+ */
+static int scarlett2_update_volumes(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       struct scarlett2_usb_volume_status volume_status;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int err, i;
+       int mute;
+
+       private->vol_updated = 0;
+
+       err = scarlett2_usb_get_volume_status(mixer, &volume_status);
+       if (err < 0)
+               return err;
+
+       private->master_vol = clamp(
+               volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
+               0, SCARLETT2_VOLUME_BIAS);
+
+       if (info->line_out_hw_vol)
+               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
+                       private->dim_mute[i] = !!volume_status.dim_mute[i];
+
+       mute = private->dim_mute[SCARLETT2_BUTTON_MUTE];
+
+       for (i = 0; i < num_line_out; i++)
+               if (private->vol_sw_hw_switch[i]) {
+                       private->vol[i] = private->master_vol;
+                       private->mute_switch[i] = mute;
+               }
+
+       return 0;
+}
+
+static int scarlett2_volume_ctl_info(struct snd_kcontrol *kctl,
+                                    struct snd_ctl_elem_info *uinfo)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+
+       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+       uinfo->count = elem->channels;
+       uinfo->value.integer.min = 0;
+       uinfo->value.integer.max = SCARLETT2_VOLUME_BIAS;
+       uinfo->value.integer.step = 1;
+       return 0;
+}
+
+static int scarlett2_master_volume_ctl_get(struct snd_kcontrol *kctl,
+                                          struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->vol_updated)
+               scarlett2_update_volumes(mixer);
+       mutex_unlock(&private->data_mutex);
+
+       ucontrol->value.integer.value[0] = private->master_vol;
+       return 0;
+}
+
+static int line_out_remap(struct scarlett2_data *private, int index)
+{
+       const struct scarlett2_device_info *info = private->info;
+
+       if (!info->line_out_remap_enable)
+               return index;
+       return info->line_out_remap[index];
+}
+
+static int scarlett2_volume_ctl_get(struct snd_kcontrol *kctl,
+                                   struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = line_out_remap(private, elem->control);
+
+       mutex_lock(&private->data_mutex);
+       if (private->vol_updated)
+               scarlett2_update_volumes(mixer);
+       mutex_unlock(&private->data_mutex);
+
+       ucontrol->value.integer.value[0] = private->vol[index];
+       return 0;
+}
+
+static int scarlett2_volume_ctl_put(struct snd_kcontrol *kctl,
+                                   struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = line_out_remap(private, elem->control);
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->vol[index];
+       val = ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->vol[index] = val;
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
+                                      index, val - SCARLETT2_VOLUME_BIAS);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const DECLARE_TLV_DB_MINMAX(
+       db_scale_scarlett2_gain, -SCARLETT2_VOLUME_BIAS * 100, 0
+);
+
+static const struct snd_kcontrol_new scarlett2_master_volume_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .access = SNDRV_CTL_ELEM_ACCESS_READ |
+                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+       .name = "",
+       .info = scarlett2_volume_ctl_info,
+       .get  = scarlett2_master_volume_ctl_get,
+       .private_value = 0, /* max value */
+       .tlv = { .p = db_scale_scarlett2_gain }
+};
+
+static const struct snd_kcontrol_new scarlett2_line_out_volume_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+       .name = "",
+       .info = scarlett2_volume_ctl_info,
+       .get  = scarlett2_volume_ctl_get,
+       .put  = scarlett2_volume_ctl_put,
+       .private_value = 0, /* max value */
+       .tlv = { .p = db_scale_scarlett2_gain }
+};
+
+/*** Mute Switch Controls ***/
+
+static int scarlett2_mute_ctl_get(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = line_out_remap(private, elem->control);
+
+       mutex_lock(&private->data_mutex);
+       if (private->vol_updated)
+               scarlett2_update_volumes(mixer);
+       mutex_unlock(&private->data_mutex);
+
+       ucontrol->value.integer.value[0] = private->mute_switch[index];
+       return 0;
+}
+
+static int scarlett2_mute_ctl_put(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = line_out_remap(private, elem->control);
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->mute_switch[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->mute_switch[index] = val;
+
+       /* Send mute change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_mute_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_mute_ctl_get,
+       .put  = scarlett2_mute_ctl_put,
+};
+
+/*** HW/SW Volume Switch Controls ***/
+
+static void scarlett2_sw_hw_ctl_ro(struct scarlett2_data *private, int index)
+{
+       private->sw_hw_ctls[index]->vd[0].access &=
+               ~SNDRV_CTL_ELEM_ACCESS_WRITE;
+}
+
+static void scarlett2_sw_hw_ctl_rw(struct scarlett2_data *private, int index)
+{
+       private->sw_hw_ctls[index]->vd[0].access |=
+               SNDRV_CTL_ELEM_ACCESS_WRITE;
+}
+
+static int scarlett2_sw_hw_enum_ctl_info(struct snd_kcontrol *kctl,
+                                        struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[2] = {
+               "SW", "HW"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 2, values);
+}
+
+static int scarlett2_sw_hw_enum_ctl_get(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+       int index = line_out_remap(private, elem->control);
+
+       ucontrol->value.enumerated.item[0] = private->vol_sw_hw_switch[index];
+       return 0;
+}
+
+static void scarlett2_vol_ctl_set_writable(struct usb_mixer_interface *mixer,
+                                          int index, int value)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       struct snd_card *card = mixer->chip->card;
+
+       /* Set/Clear write bits */
+       if (value) {
+               private->vol_ctls[index]->vd[0].access |=
+                       SNDRV_CTL_ELEM_ACCESS_WRITE;
+               private->mute_ctls[index]->vd[0].access |=
+                       SNDRV_CTL_ELEM_ACCESS_WRITE;
+       } else {
+               private->vol_ctls[index]->vd[0].access &=
+                       ~SNDRV_CTL_ELEM_ACCESS_WRITE;
+               private->mute_ctls[index]->vd[0].access &=
+                       ~SNDRV_CTL_ELEM_ACCESS_WRITE;
+       }
+
+       /* Notify of write bit and possible value change */
+       snd_ctl_notify(card,
+                      SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
+                      &private->vol_ctls[index]->id);
+       snd_ctl_notify(card,
+                      SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
+                      &private->mute_ctls[index]->id);
+}
+
+static int scarlett2_sw_hw_change(struct usb_mixer_interface *mixer,
+                                 int ctl_index, int val)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       int index = line_out_remap(private, ctl_index);
+       int err;
+
+       private->vol_sw_hw_switch[index] = val;
+
+       /* Change access mode to RO (hardware controlled volume)
+        * or RW (software controlled volume)
+        */
+       scarlett2_vol_ctl_set_writable(mixer, ctl_index, !val);
+
+       /* Reset volume/mute to master volume/mute */
+       private->vol[index] = private->master_vol;
+       private->mute_switch[index] = private->dim_mute[SCARLETT2_BUTTON_MUTE];
+
+       /* Set SW volume to current HW volume */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
+               index, private->master_vol - SCARLETT2_VOLUME_BIAS);
+       if (err < 0)
+               return err;
+
+       /* Set SW mute to current HW mute */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
+               index, private->dim_mute[SCARLETT2_BUTTON_MUTE]);
+       if (err < 0)
+               return err;
+
+       /* Send SW/HW switch change to the device */
+       return scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_SW_HW_SWITCH,
+                                       index, val);
+}
+
+static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int ctl_index = elem->control;
+       int index = line_out_remap(private, ctl_index);
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->vol_sw_hw_switch[index];
+       val = !!ucontrol->value.enumerated.item[0];
+
+       if (oval == val)
+               goto unlock;
+
+       err = scarlett2_sw_hw_change(mixer, ctl_index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_sw_hw_enum_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = scarlett2_sw_hw_enum_ctl_info,
+       .get  = scarlett2_sw_hw_enum_ctl_get,
+       .put  = scarlett2_sw_hw_enum_ctl_put,
+};
+
+/*** Line Level/Instrument Level Switch Controls ***/
+
+static int scarlett2_update_input_other(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       private->input_other_updated = 0;
+
+       if (info->level_input_count) {
+               int err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_LEVEL_SWITCH,
+                       info->level_input_count + info->level_input_first,
+                       private->level_switch);
+               if (err < 0)
+                       return err;
+       }
+
+       if (info->pad_input_count) {
+               int err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_PAD_SWITCH,
+                       info->pad_input_count, private->pad_switch);
+               if (err < 0)
+                       return err;
+       }
+
+       if (info->air_input_count) {
+               int err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_AIR_SWITCH,
+                       info->air_input_count, private->air_switch);
+               if (err < 0)
+                       return err;
+       }
+
+       if (info->phantom_count) {
+               int err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_PHANTOM_SWITCH,
+                       info->phantom_count, private->phantom_switch);
+               if (err < 0)
+                       return err;
+
+               err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_PHANTOM_PERSISTENCE,
+                       1, &private->phantom_persistence);
+               if (err < 0)
+                       return err;
+       }
+
+       return 0;
+}
+
+static int scarlett2_level_enum_ctl_info(struct snd_kcontrol *kctl,
+                                        struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[2] = {
+               "Line", "Inst"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 2, values);
+}
+
+static int scarlett2_level_enum_ctl_get(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       int index = elem->control + info->level_input_first;
+
+       mutex_lock(&private->data_mutex);
+       if (private->input_other_updated)
+               scarlett2_update_input_other(mixer);
+       ucontrol->value.enumerated.item[0] = private->level_switch[index];
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_level_enum_ctl_put(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       int index = elem->control + info->level_input_first;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->level_switch[index];
+       val = !!ucontrol->value.enumerated.item[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->level_switch[index] = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_LEVEL_SWITCH,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_level_enum_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = scarlett2_level_enum_ctl_info,
+       .get  = scarlett2_level_enum_ctl_get,
+       .put  = scarlett2_level_enum_ctl_put,
+};
+
+/*** Pad Switch Controls ***/
+
+static int scarlett2_pad_ctl_get(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->input_other_updated)
+               scarlett2_update_input_other(mixer);
+       ucontrol->value.integer.value[0] =
+               private->pad_switch[elem->control];
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_pad_ctl_put(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->pad_switch[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->pad_switch[index] = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_PAD_SWITCH,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_pad_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_pad_ctl_get,
+       .put  = scarlett2_pad_ctl_put,
+};
+
+/*** Air Switch Controls ***/
+
+static int scarlett2_air_ctl_get(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->input_other_updated)
+               scarlett2_update_input_other(mixer);
+       ucontrol->value.integer.value[0] = private->air_switch[elem->control];
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_air_ctl_put(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->air_switch[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->air_switch[index] = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_AIR_SWITCH,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_air_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_air_ctl_get,
+       .put  = scarlett2_air_ctl_put,
+};
+
+/*** Phantom Switch Controls ***/
+
+static int scarlett2_phantom_ctl_get(struct snd_kcontrol *kctl,
+                                    struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->input_other_updated)
+               scarlett2_update_input_other(mixer);
+       ucontrol->value.integer.value[0] =
+               private->phantom_switch[elem->control];
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_phantom_ctl_put(struct snd_kcontrol *kctl,
+                                    struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->phantom_switch[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->phantom_switch[index] = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_PHANTOM_SWITCH,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_phantom_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_phantom_ctl_get,
+       .put  = scarlett2_phantom_ctl_put,
+};
+
+/*** Phantom Persistence Control ***/
+
+static int scarlett2_phantom_persistence_ctl_get(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+
+       ucontrol->value.integer.value[0] = private->phantom_persistence;
+       return 0;
+}
+
+static int scarlett2_phantom_persistence_ctl_put(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->phantom_persistence;
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->phantom_persistence = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_PHANTOM_PERSISTENCE, index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_phantom_persistence_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_phantom_persistence_ctl_get,
+       .put  = scarlett2_phantom_persistence_ctl_put,
+};
+
+/*** Direct Monitor Control ***/
+
+static int scarlett2_update_monitor_other(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       int err;
+
+       /* monitor_other_enable[0] enables speaker switching
+        * monitor_other_enable[1] enables talkback
+        */
+       u8 monitor_other_enable[2];
+
+       /* monitor_other_switch[0] activates the alternate speakers
+        * monitor_other_switch[1] activates talkback
+        */
+       u8 monitor_other_switch[2];
+
+       private->monitor_other_updated = 0;
+
+       if (info->direct_monitor)
+               return scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_DIRECT_MONITOR,
+                       1, &private->direct_monitor_switch);
+
+       /* if it doesn't do speaker switching then it also doesn't do
+        * talkback
+        */
+       if (!info->has_speaker_switching)
+               return 0;
+
+       err = scarlett2_usb_get_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
+               2, monitor_other_enable);
+       if (err < 0)
+               return err;
+
+       err = scarlett2_usb_get_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
+               2, monitor_other_switch);
+       if (err < 0)
+               return err;
+
+       if (!monitor_other_enable[0])
+               private->speaker_switching_switch = 0;
+       else
+               private->speaker_switching_switch = monitor_other_switch[0] + 1;
+
+       if (info->has_talkback) {
+               const int (*port_count)[SCARLETT2_PORT_DIRNS] =
+                       info->port_count;
+               int num_mixes =
+                       port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
+               u16 bitmap;
+               int i;
+
+               if (!monitor_other_enable[1])
+                       private->talkback_switch = 0;
+               else
+                       private->talkback_switch = monitor_other_switch[1] + 1;
+
+               err = scarlett2_usb_get_config(mixer,
+                                              SCARLETT2_CONFIG_TALKBACK_MAP,
+                                              1, &bitmap);
+               if (err < 0)
+                       return err;
+               for (i = 0; i < num_mixes; i++, bitmap >>= 1)
+                       private->talkback_map[i] = bitmap & 1;
+       }
+
+       return 0;
+}
+
+static int scarlett2_direct_monitor_ctl_get(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->monitor_other_updated)
+               scarlett2_update_monitor_other(mixer);
+       ucontrol->value.enumerated.item[0] = private->direct_monitor_switch;
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_direct_monitor_ctl_put(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->direct_monitor_switch;
+       val = min(ucontrol->value.enumerated.item[0], 2U);
+
+       if (oval == val)
+               goto unlock;
+
+       private->direct_monitor_switch = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_DIRECT_MONITOR, index, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static int scarlett2_direct_monitor_stereo_enum_ctl_info(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[3] = {
+               "Off", "Mono", "Stereo"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 3, values);
+}
+
+/* Direct Monitor for Solo is mono-only and only needs a boolean control
+ * Direct Monitor for 2i2 is selectable between Off/Mono/Stereo
+ */
+static const struct snd_kcontrol_new scarlett2_direct_monitor_ctl[2] = {
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+               .name = "",
+               .info = snd_ctl_boolean_mono_info,
+               .get  = scarlett2_direct_monitor_ctl_get,
+               .put  = scarlett2_direct_monitor_ctl_put,
+       },
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+               .name = "",
+               .info = scarlett2_direct_monitor_stereo_enum_ctl_info,
+               .get  = scarlett2_direct_monitor_ctl_get,
+               .put  = scarlett2_direct_monitor_ctl_put,
+       }
+};
+
+static int scarlett2_add_direct_monitor_ctl(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const char *s;
+
+       if (!info->direct_monitor)
+               return 0;
+
+       s = info->direct_monitor == 1
+             ? "Direct Monitor Playback Switch"
+             : "Direct Monitor Playback Enum";
+
+       return scarlett2_add_new_ctl(
+               mixer, &scarlett2_direct_monitor_ctl[info->direct_monitor - 1],
+               0, 1, s, &private->direct_monitor_ctl);
+}
+
+/*** Speaker Switching Control ***/
+
+static int scarlett2_speaker_switch_enum_ctl_info(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[3] = {
+               "Off", "Main", "Alt"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 3, values);
+}
+
+static int scarlett2_speaker_switch_enum_ctl_get(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->monitor_other_updated)
+               scarlett2_update_monitor_other(mixer);
+       ucontrol->value.enumerated.item[0] = private->speaker_switching_switch;
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+/* when speaker switching gets enabled, switch the main/alt speakers
+ * to HW volume and disable those controls
+ */
+static int scarlett2_speaker_switch_enable(struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       int i, err;
+
+       for (i = 0; i < 4; i++) {
+               int index = line_out_remap(private, i);
+
+               /* switch the main/alt speakers to HW volume */
+               if (!private->vol_sw_hw_switch[index]) {
+                       err = scarlett2_sw_hw_change(private->mixer, i, 1);
+                       if (err < 0)
+                               return err;
+               }
+
+               /* disable the line out SW/HW switch */
+               scarlett2_sw_hw_ctl_ro(private, i);
+               snd_ctl_notify(card,
+                              SNDRV_CTL_EVENT_MASK_VALUE |
+                                SNDRV_CTL_EVENT_MASK_INFO,
+                              &private->sw_hw_ctls[i]->id);
+       }
+
+       /* when the next monitor-other notify comes in, update the mux
+        * configuration
+        */
+       private->speaker_switching_switched = 1;
+
+       return 0;
+}
+
+/* when speaker switching gets disabled, reenable the hw/sw controls
+ * and invalidate the routing
+ */
+static void scarlett2_speaker_switch_disable(struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       int i;
+
+       /* enable the line out SW/HW switch */
+       for (i = 0; i < 4; i++) {
+               scarlett2_sw_hw_ctl_rw(private, i);
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+                              &private->sw_hw_ctls[i]->id);
+       }
+
+       /* when the next monitor-other notify comes in, update the mux
+        * configuration
+        */
+       private->speaker_switching_switched = 1;
+}
+
+static int scarlett2_speaker_switch_enum_ctl_put(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->speaker_switching_switch;
+       val = min(ucontrol->value.enumerated.item[0], 2U);
+
+       if (oval == val)
+               goto unlock;
+
+       private->speaker_switching_switch = val;
+
+       /* enable/disable speaker switching */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
+               0, !!val);
+       if (err < 0)
+               goto unlock;
+
+       /* if speaker switching is enabled, select main or alt */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
+               0, val == 2);
+       if (err < 0)
+               goto unlock;
+
+       /* update controls if speaker switching gets enabled or disabled */
+       if (!oval && val)
+               err = scarlett2_speaker_switch_enable(mixer);
+       else if (oval && !val)
+               scarlett2_speaker_switch_disable(mixer);
+
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_speaker_switch_enum_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = scarlett2_speaker_switch_enum_ctl_info,
+       .get  = scarlett2_speaker_switch_enum_ctl_get,
+       .put  = scarlett2_speaker_switch_enum_ctl_put,
+};
+
+static int scarlett2_add_speaker_switch_ctl(
+       struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       if (!info->has_speaker_switching)
+               return 0;
+
+       return scarlett2_add_new_ctl(
+               mixer, &scarlett2_speaker_switch_enum_ctl,
+               0, 1, "Speaker Switching Playback Enum",
+               &private->speaker_switching_ctl);
+}
+
+/*** Talkback and Talkback Map Controls ***/
+
+static int scarlett2_talkback_enum_ctl_info(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[3] = {
+               "Disabled", "Off", "On"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 3, values);
+}
+
+static int scarlett2_talkback_enum_ctl_get(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->monitor_other_updated)
+               scarlett2_update_monitor_other(mixer);
+       ucontrol->value.enumerated.item[0] = private->talkback_switch;
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_talkback_enum_ctl_put(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->talkback_switch;
+       val = min(ucontrol->value.enumerated.item[0], 2U);
+
+       if (oval == val)
+               goto unlock;
+
+       private->talkback_switch = val;
+
+       /* enable/disable talkback */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
+               1, !!val);
+       if (err < 0)
+               goto unlock;
+
+       /* if talkback is enabled, select main or alt */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
+               1, val == 2);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_talkback_enum_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = scarlett2_talkback_enum_ctl_info,
+       .get  = scarlett2_talkback_enum_ctl_get,
+       .put  = scarlett2_talkback_enum_ctl_put,
+};
+
+static int scarlett2_talkback_map_ctl_get(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = elem->control;
+
+       ucontrol->value.integer.value[0] = private->talkback_map[index];
+
+       return 0;
+}
+
+static int scarlett2_talkback_map_ctl_put(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] =
+               private->info->port_count;
+       int num_mixes = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
+
+       int index = elem->control;
+       int oval, val, err = 0, i;
+       u16 bitmap = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->talkback_map[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->talkback_map[index] = val;
+
+       for (i = 0; i < num_mixes; i++)
+               bitmap |= private->talkback_map[i] << i;
+
+       /* Send updated bitmap to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_TALKBACK_MAP,
+                                      0, bitmap);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_talkback_map_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_talkback_map_ctl_get,
+       .put  = scarlett2_talkback_map_ctl_put,
+};
+
+static int scarlett2_add_talkback_ctls(
+       struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_mixes = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
+       int err, i;
+       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+
+       if (!info->has_talkback)
+               return 0;
+
+       err = scarlett2_add_new_ctl(
+               mixer, &scarlett2_talkback_enum_ctl,
+               0, 1, "Talkback Playback Enum",
+               &private->talkback_ctl);
+       if (err < 0)
+               return err;
+
+       for (i = 0; i < num_mixes; i++) {
+               snprintf(s, sizeof(s),
+                        "Talkback Mix %c Playback Switch", i + 'A');
+               err = scarlett2_add_new_ctl(mixer, &scarlett2_talkback_map_ctl,
+                                           i, 1, s, NULL);
+               if (err < 0)
+                       return err;
+       }
+
+       return 0;
+}
+
+/*** Dim/Mute Controls ***/
+
+static int scarlett2_dim_mute_ctl_get(struct snd_kcontrol *kctl,
+                                     struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       mutex_lock(&private->data_mutex);
+       if (private->vol_updated)
+               scarlett2_update_volumes(mixer);
+       mutex_unlock(&private->data_mutex);
+
+       ucontrol->value.integer.value[0] = private->dim_mute[elem->control];
+       return 0;
+}
+
+static int scarlett2_dim_mute_ctl_put(struct snd_kcontrol *kctl,
+                                     struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+
+       int index = elem->control;
+       int oval, val, err = 0, i;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->dim_mute[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->dim_mute[index] = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_DIM_MUTE,
+                                      index, val);
+       if (err == 0)
+               err = 1;
+
+       if (index == SCARLETT2_BUTTON_MUTE)
+               for (i = 0; i < num_line_out; i++) {
+                       int line_index = line_out_remap(private, i);
+
+                       if (private->vol_sw_hw_switch[line_index]) {
+                               private->mute_switch[line_index] = val;
+                               snd_ctl_notify(mixer->chip->card,
+                                              SNDRV_CTL_EVENT_MASK_VALUE,
+                                              &private->mute_ctls[i]->id);
+                       }
+               }
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_dim_mute_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_dim_mute_ctl_get,
+       .put  = scarlett2_dim_mute_ctl_put
+};
+
+/*** Create the analogue output controls ***/
+
+static int scarlett2_add_line_out_ctls(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int err, i;
+       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+
+       /* Add R/O HW volume control */
+       if (info->line_out_hw_vol) {
+               snprintf(s, sizeof(s), "Master HW Playback Volume");
+               err = scarlett2_add_new_ctl(mixer,
+                                           &scarlett2_master_volume_ctl,
+                                           0, 1, s, &private->master_vol_ctl);
+               if (err < 0)
+                       return err;
+       }
+
+       /* Add volume controls */
+       for (i = 0; i < num_line_out; i++) {
+               int index = line_out_remap(private, i);
+
+               /* Fader */
+               if (info->line_out_descrs[i])
+                       snprintf(s, sizeof(s),
+                                "Line %02d (%s) Playback Volume",
+                                i + 1, info->line_out_descrs[i]);
+               else
+                       snprintf(s, sizeof(s),
+                                "Line %02d Playback Volume",
+                                i + 1);
+               err = scarlett2_add_new_ctl(mixer,
+                                           &scarlett2_line_out_volume_ctl,
+                                           i, 1, s, &private->vol_ctls[i]);
+               if (err < 0)
+                       return err;
+
+               /* Mute Switch */
+               snprintf(s, sizeof(s),
+                        "Line %02d Mute Playback Switch",
+                        i + 1);
+               err = scarlett2_add_new_ctl(mixer,
+                                           &scarlett2_mute_ctl,
+                                           i, 1, s,
+                                           &private->mute_ctls[i]);
+               if (err < 0)
+                       return err;
+
+               /* Make the fader and mute controls read-only if the
+                * SW/HW switch is set to HW
+                */
+               if (private->vol_sw_hw_switch[index])
+                       scarlett2_vol_ctl_set_writable(mixer, i, 0);
+
+               /* SW/HW Switch */
+               if (info->line_out_hw_vol) {
+                       snprintf(s, sizeof(s),
+                                "Line Out %02d Volume Control Playback Enum",
+                                i + 1);
+                       err = scarlett2_add_new_ctl(mixer,
+                                                   &scarlett2_sw_hw_enum_ctl,
+                                                   i, 1, s,
+                                                   &private->sw_hw_ctls[i]);
+                       if (err < 0)
+                               return err;
+
+                       /* Make the switch read-only if the line is
+                        * involved in speaker switching
+                        */
+                       if (private->speaker_switching_switch && i < 4)
+                               scarlett2_sw_hw_ctl_ro(private, i);
+               }
+       }
+
+       /* Add dim/mute controls */
+       if (info->line_out_hw_vol)
+               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++) {
+                       err = scarlett2_add_new_ctl(
+                               mixer, &scarlett2_dim_mute_ctl,
+                               i, 1, scarlett2_dim_mute_names[i],
+                               &private->dim_mute_ctls[i]);
+                       if (err < 0)
+                               return err;
+               }
+
+       return 0;
+}
+
+/*** Create the analogue input controls ***/
+
+static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       int err, i;
+       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+       const char *fmt = "Line In %d %s Capture %s";
+       const char *fmt2 = "Line In %d-%d %s Capture %s";
+
+       /* Add input level (line/inst) controls */
+       for (i = 0; i < info->level_input_count; i++) {
+               snprintf(s, sizeof(s), fmt, i + 1 + info->level_input_first,
+                        "Level", "Enum");
+               err = scarlett2_add_new_ctl(mixer, &scarlett2_level_enum_ctl,
+                                           i, 1, s, &private->level_ctls[i]);
+               if (err < 0)
+                       return err;
+       }
+
+       /* Add input pad controls */
+       for (i = 0; i < info->pad_input_count; i++) {
+               snprintf(s, sizeof(s), fmt, i + 1, "Pad", "Switch");
+               err = scarlett2_add_new_ctl(mixer, &scarlett2_pad_ctl,
+                                           i, 1, s, &private->pad_ctls[i]);
+               if (err < 0)
+                       return err;
+       }
+
+       /* Add input air controls */
+       for (i = 0; i < info->air_input_count; i++) {
+               snprintf(s, sizeof(s), fmt, i + 1, "Air", "Switch");
+               err = scarlett2_add_new_ctl(mixer, &scarlett2_air_ctl,
+                                           i, 1, s, &private->air_ctls[i]);
+               if (err < 0)
+                       return err;
+       }
+
+       /* Add input phantom controls */
+       if (info->inputs_per_phantom == 1) {
+               for (i = 0; i < info->phantom_count; i++) {
+                       scnprintf(s, sizeof(s), fmt, i + 1,
+                                 "Phantom Power", "Switch");
+                       err = scarlett2_add_new_ctl(
+                               mixer, &scarlett2_phantom_ctl,
+                               i, 1, s, &private->phantom_ctls[i]);
+                       if (err < 0)
+                               return err;
+               }
+       } else if (info->inputs_per_phantom > 1) {
+               for (i = 0; i < info->phantom_count; i++) {
+                       int from = i * info->inputs_per_phantom + 1;
+                       int to = (i + 1) * info->inputs_per_phantom;
+
+                       scnprintf(s, sizeof(s), fmt2, from, to,
+                                 "Phantom Power", "Switch");
+                       err = scarlett2_add_new_ctl(
+                               mixer, &scarlett2_phantom_ctl,
+                               i, 1, s, &private->phantom_ctls[i]);
+                       if (err < 0)
+                               return err;
+               }
+       }
+       if (info->phantom_count) {
+               err = scarlett2_add_new_ctl(
+                       mixer, &scarlett2_phantom_persistence_ctl, 0, 1,
+                       "Phantom Power Persistence Capture Switch", NULL);
+               if (err < 0)
+                       return err;
+       }
+
+       return 0;
+}
+
+/*** Mixer Volume Controls ***/
+
+static int scarlett2_mixer_ctl_info(struct snd_kcontrol *kctl,
+                                   struct snd_ctl_elem_info *uinfo)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+
+       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+       uinfo->count = elem->channels;
+       uinfo->value.integer.min = 0;
+       uinfo->value.integer.max = SCARLETT2_MIXER_MAX_VALUE;
+       uinfo->value.integer.step = 1;
+       return 0;
+}
+
+static int scarlett2_mixer_ctl_get(struct snd_kcontrol *kctl,
+                                  struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+
+       ucontrol->value.integer.value[0] = private->mix[elem->control];
+       return 0;
+}
+
+static int scarlett2_mixer_ctl_put(struct snd_kcontrol *kctl,
+                                  struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int oval, val, num_mixer_in, mix_num, err = 0;
+       int index = elem->control;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->mix[index];
+       val = ucontrol->value.integer.value[0];
+       num_mixer_in = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
+       mix_num = index / num_mixer_in;
+
+       if (oval == val)
+               goto unlock;
+
+       private->mix[index] = val;
+       err = scarlett2_usb_set_mix(mixer, mix_num);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const DECLARE_TLV_DB_MINMAX(
+       db_scale_scarlett2_mixer,
+       SCARLETT2_MIXER_MIN_DB * 100,
+       SCARLETT2_MIXER_MAX_DB * 100
+);
+
+static const struct snd_kcontrol_new scarlett2_mixer_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+       .name = "",
+       .info = scarlett2_mixer_ctl_info,
+       .get  = scarlett2_mixer_ctl_get,
+       .put  = scarlett2_mixer_ctl_put,
+       .private_value = SCARLETT2_MIXER_MAX_DB, /* max value */
+       .tlv = { .p = db_scale_scarlett2_mixer }
+};
+
+static int scarlett2_add_mixer_ctls(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int err, i, j;
+       int index;
+       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+
+       int num_inputs =
+               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
+       int num_outputs =
+               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
+
+       for (i = 0, index = 0; i < num_outputs; i++)
+               for (j = 0; j < num_inputs; j++, index++) {
+                       snprintf(s, sizeof(s),
+                                "Mix %c Input %02d Playback Volume",
+                                'A' + i, j + 1);
+                       err = scarlett2_add_new_ctl(mixer, &scarlett2_mixer_ctl,
+                                                   index, 1, s, NULL);
+                       if (err < 0)
+                               return err;
+               }
+
+       return 0;
+}
+
+/*** Mux Source Selection Controls ***/
+
+static int scarlett2_mux_src_enum_ctl_info(struct snd_kcontrol *kctl,
+                                          struct snd_ctl_elem_info *uinfo)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       unsigned int item = uinfo->value.enumerated.item;
+       int items = private->num_mux_srcs;
+       int port_type;
+
+       uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
+       uinfo->count = elem->channels;
+       uinfo->value.enumerated.items = items;
+
+       if (item >= items)
+               item = uinfo->value.enumerated.item = items - 1;
+
+       for (port_type = 0;
+            port_type < SCARLETT2_PORT_TYPE_COUNT;
+            port_type++) {
+               if (item < port_count[port_type][SCARLETT2_PORT_IN]) {
+                       const struct scarlett2_port *port =
+                               &scarlett2_ports[port_type];
+
+                       sprintf(uinfo->value.enumerated.name,
+                               port->src_descr, item + port->src_num_offset);
+                       return 0;
+               }
+               item -= port_count[port_type][SCARLETT2_PORT_IN];
+       }
+
+       return -EINVAL;
+}
+
+static int scarlett2_mux_src_enum_ctl_get(struct snd_kcontrol *kctl,
+                                         struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int line_out_count =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int index = elem->control;
+
+       if (index < line_out_count)
+               index = line_out_remap(private, index);
+
+       mutex_lock(&private->data_mutex);
+       if (private->mux_updated)
+               scarlett2_usb_get_mux(mixer);
+       ucontrol->value.enumerated.item[0] = private->mux[index];
+       mutex_unlock(&private->data_mutex);
+
+       return 0;
+}
+
+static int scarlett2_mux_src_enum_ctl_put(struct snd_kcontrol *kctl,
+                                         struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int line_out_count =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       if (index < line_out_count)
+               index = line_out_remap(private, index);
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->mux[index];
+       val = min(ucontrol->value.enumerated.item[0],
+                 private->num_mux_srcs - 1U);
+
+       if (oval == val)
+               goto unlock;
+
+       private->mux[index] = val;
+       err = scarlett2_usb_set_mux(mixer);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_mux_src_enum_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = scarlett2_mux_src_enum_ctl_info,
+       .get  = scarlett2_mux_src_enum_ctl_get,
+       .put  = scarlett2_mux_src_enum_ctl_put,
+};
+
+static int scarlett2_add_mux_enums(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int port_type, channel, i;
+
+       for (i = 0, port_type = 0;
+            port_type < SCARLETT2_PORT_TYPE_COUNT;
+            port_type++) {
+               for (channel = 0;
+                    channel < port_count[port_type][SCARLETT2_PORT_OUT];
+                    channel++, i++) {
+                       int err;
+                       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+                       const char *const descr =
+                               scarlett2_ports[port_type].dst_descr;
+
+                       snprintf(s, sizeof(s) - 5, descr, channel + 1);
+                       strcat(s, " Enum");
+
+                       err = scarlett2_add_new_ctl(mixer,
+                                                   &scarlett2_mux_src_enum_ctl,
+                                                   i, 1, s,
+                                                   &private->mux_ctls[i]);
+                       if (err < 0)
+                               return err;
+               }
+       }
+
+       return 0;
+}
+
+/*** Meter Controls ***/
+
+static int scarlett2_meter_ctl_info(struct snd_kcontrol *kctl,
+                                   struct snd_ctl_elem_info *uinfo)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+
+       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+       uinfo->count = elem->channels;
+       uinfo->value.integer.min = 0;
+       uinfo->value.integer.max = 4095;
+       uinfo->value.integer.step = 1;
+       return 0;
+}
+
+static int scarlett2_meter_ctl_get(struct snd_kcontrol *kctl,
+                                  struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       u16 meter_levels[SCARLETT2_MAX_METERS];
+       int i, err;
+
+       err = scarlett2_usb_get_meter_levels(elem->head.mixer, elem->channels,
+                                            meter_levels);
+       if (err < 0)
+               return err;
+
+       for (i = 0; i < elem->channels; i++)
+               ucontrol->value.integer.value[i] = meter_levels[i];
+
+       return 0;
+}
+
+static const struct snd_kcontrol_new scarlett2_meter_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+       .access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+       .name = "",
+       .info = scarlett2_meter_ctl_info,
+       .get  = scarlett2_meter_ctl_get
+};
+
+static int scarlett2_add_meter_ctl(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       /* devices without a mixer also don't support reporting levels */
+       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
+               return 0;
+
+       return scarlett2_add_new_ctl(mixer, &scarlett2_meter_ctl,
+                                    0, private->num_mux_dsts,
+                                    "Level Meter", NULL);
+}
+
+/*** MSD Controls ***/
+
+static int scarlett2_msd_ctl_get(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+
+       ucontrol->value.integer.value[0] = private->msd_switch;
+       return 0;
+}
+
+static int scarlett2_msd_ctl_put(struct snd_kcontrol *kctl,
+                                struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->msd_switch;
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->msd_switch = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MSD_SWITCH,
+                                      0, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_msd_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_msd_ctl_get,
+       .put  = scarlett2_msd_ctl_put,
+};
+
+static int scarlett2_add_msd_ctl(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       if (!info->has_msd_mode)
+               return 0;
+
+       /* If MSD mode is off, hide the switch by default */
+       if (!private->msd_switch && !(mixer->chip->setup & SCARLETT2_MSD_ENABLE))
+               return 0;
+
+       /* Add MSD control */
+       return scarlett2_add_new_ctl(mixer, &scarlett2_msd_ctl,
+                                    0, 1, "MSD Mode Switch", NULL);
+}
+
+/*** Standalone Control ***/
+
+static int scarlett2_standalone_ctl_get(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+
+       ucontrol->value.integer.value[0] = private->standalone_switch;
+       return 0;
+}
+
+static int scarlett2_standalone_ctl_put(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->standalone_switch;
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->standalone_switch = val;
+
+       /* Send switch change to the device */
+       err = scarlett2_usb_set_config(mixer,
+                                      SCARLETT2_CONFIG_STANDALONE_SWITCH,
+                                      0, val);
+       if (err == 0)
+               err = 1;
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_standalone_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_standalone_ctl_get,
+       .put  = scarlett2_standalone_ctl_put,
+};
+
+static int scarlett2_add_standalone_ctl(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
+               return 0;
+
+       /* Add standalone control */
+       return scarlett2_add_new_ctl(mixer, &scarlett2_standalone_ctl,
+                                    0, 1, "Standalone Switch", NULL);
+}
+
+/*** Cleanup/Suspend Callbacks ***/
+
+static void scarlett2_private_free(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       cancel_delayed_work_sync(&private->work);
+       kfree(private);
+       mixer->private_data = NULL;
+}
+
+static void scarlett2_private_suspend(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       if (cancel_delayed_work_sync(&private->work))
+               scarlett2_config_save(private->mixer);
+}
+
+/*** Initialisation ***/
+
+static void scarlett2_count_mux_io(struct scarlett2_data *private)
+{
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int port_type, srcs = 0, dsts = 0;
+
+       for (port_type = 0;
+            port_type < SCARLETT2_PORT_TYPE_COUNT;
+            port_type++) {
+               srcs += port_count[port_type][SCARLETT2_PORT_IN];
+               dsts += port_count[port_type][SCARLETT2_PORT_OUT];
+       }
+
+       private->num_mux_srcs = srcs;
+       private->num_mux_dsts = dsts;
+}
+
+/* Look through the interface descriptors for the Focusrite Control
+ * interface (bInterfaceClass = 255 Vendor Specific Class) and set
+ * bInterfaceNumber, bEndpointAddress, wMaxPacketSize, and bInterval
+ * in private
+ */
+static int scarlett2_find_fc_interface(struct usb_device *dev,
+                                      struct scarlett2_data *private)
+{
+       struct usb_host_config *config = dev->actconfig;
+       int i;
+
+       for (i = 0; i < config->desc.bNumInterfaces; i++) {
+               struct usb_interface *intf = config->interface[i];
+               struct usb_interface_descriptor *desc =
+                       &intf->altsetting[0].desc;
+               struct usb_endpoint_descriptor *epd;
+
+               if (desc->bInterfaceClass != 255)
+                       continue;
+
+               epd = get_endpoint(intf->altsetting, 0);
+               private->bInterfaceNumber = desc->bInterfaceNumber;
+               private->bEndpointAddress = epd->bEndpointAddress &
+                       USB_ENDPOINT_NUMBER_MASK;
+               private->wMaxPacketSize = le16_to_cpu(epd->wMaxPacketSize);
+               private->bInterval = epd->bInterval;
+               return 0;
+       }
+
+       return -EINVAL;
+}
+
+/* Initialise private data */
+static int scarlett2_init_private(struct usb_mixer_interface *mixer,
+                                 const struct scarlett2_device_entry *entry)
+{
+       struct scarlett2_data *private =
+               kzalloc(sizeof(struct scarlett2_data), GFP_KERNEL);
+
+       if (!private)
+               return -ENOMEM;
+
+       mutex_init(&private->usb_mutex);
+       mutex_init(&private->data_mutex);
+       INIT_DELAYED_WORK(&private->work, scarlett2_config_save_work);
+
+       mixer->private_data = private;
+       mixer->private_free = scarlett2_private_free;
+       mixer->private_suspend = scarlett2_private_suspend;
+
+       private->info = entry->info;
+       private->series_name = entry->series_name;
+       scarlett2_count_mux_io(private);
+       private->scarlett2_seq = 0;
+       private->mixer = mixer;
+
+       return scarlett2_find_fc_interface(mixer->chip->dev, private);
+}
+
+/* Cargo cult proprietary initialisation sequence */
+static int scarlett2_usb_init(struct usb_mixer_interface *mixer)
+{
+       struct usb_device *dev = mixer->chip->dev;
+       struct scarlett2_data *private = mixer->private_data;
+       u8 buf[24];
+       int err;
+
+       if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
+               return -EINVAL;
+
+       /* step 0 */
+       err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
+                              SCARLETT2_USB_CMD_INIT, buf, sizeof(buf));
+       if (err < 0)
+               return err;
+
+       /* step 1 */
+       private->scarlett2_seq = 1;
+       err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_1, NULL, 0, NULL, 0);
+       if (err < 0)
+               return err;
+
+       /* step 2 */
+       private->scarlett2_seq = 1;
+       return scarlett2_usb(mixer, SCARLETT2_USB_INIT_2, NULL, 0, NULL, 84);
+}
+
+/* Read configuration from the interface on start */
+static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int num_mixer_out =
+               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
+       struct scarlett2_usb_volume_status volume_status;
+       int err, i;
+
+       if (info->has_msd_mode) {
+               err = scarlett2_usb_get_config(
+                       mixer, SCARLETT2_CONFIG_MSD_SWITCH,
+                       1, &private->msd_switch);
+               if (err < 0)
+                       return err;
+
+               /* no other controls are created if MSD mode is on */
+               if (private->msd_switch)
+                       return 0;
+       }
+
+       err = scarlett2_update_input_other(mixer);
+       if (err < 0)
+               return err;
+
+       err = scarlett2_update_monitor_other(mixer);
+       if (err < 0)
+               return err;
+
+       /* the rest of the configuration is for devices with a mixer */
+       if (info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
+               return 0;
+
+       err = scarlett2_usb_get_config(
+               mixer, SCARLETT2_CONFIG_STANDALONE_SWITCH,
+               1, &private->standalone_switch);
+       if (err < 0)
+               return err;
+
+       err = scarlett2_update_sync(mixer);
+       if (err < 0)
+               return err;
+
+       err = scarlett2_usb_get_volume_status(mixer, &volume_status);
+       if (err < 0)
+               return err;
+
+       if (info->line_out_hw_vol)
+               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
+                       private->dim_mute[i] = !!volume_status.dim_mute[i];
+
+       private->master_vol = clamp(
+               volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
+               0, SCARLETT2_VOLUME_BIAS);
+
+       for (i = 0; i < num_line_out; i++) {
+               int volume, mute;
+
+               private->vol_sw_hw_switch[i] =
+                       info->line_out_hw_vol
+                               && volume_status.sw_hw_switch[i];
+
+               volume = private->vol_sw_hw_switch[i]
+                          ? volume_status.master_vol
+                          : volume_status.sw_vol[i];
+               volume = clamp(volume + SCARLETT2_VOLUME_BIAS,
+                              0, SCARLETT2_VOLUME_BIAS);
+               private->vol[i] = volume;
+
+               mute = private->vol_sw_hw_switch[i]
+                        ? private->dim_mute[SCARLETT2_BUTTON_MUTE]
+                        : volume_status.mute_switch[i];
+               private->mute_switch[i] = mute;
+       }
+
+       for (i = 0; i < num_mixer_out; i++) {
+               err = scarlett2_usb_get_mix(mixer, i);
+               if (err < 0)
+                       return err;
+       }
+
+       return scarlett2_usb_get_mux(mixer);
+}
+
+/* Notify on sync change */
+static void scarlett2_notify_sync(
+       struct usb_mixer_interface *mixer)
+{
+       struct scarlett2_data *private = mixer->private_data;
+
+       private->sync_updated = 1;
+
+       snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+                      &private->sync_ctl->id);
+}
+
+/* Notify on monitor change */
+static void scarlett2_notify_monitor(
+       struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int i;
+
+       /* if line_out_hw_vol is 0, there are no controls to update */
+       if (!info->line_out_hw_vol)
+               return;
+
+       private->vol_updated = 1;
+
+       snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+                      &private->master_vol_ctl->id);
+
+       for (i = 0; i < num_line_out; i++)
+               if (private->vol_sw_hw_switch[line_out_remap(private, i)])
+                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                                      &private->vol_ctls[i]->id);
+}
+
+/* Notify on dim/mute change */
+static void scarlett2_notify_dim_mute(
+       struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+       int num_line_out =
+               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+       int i;
+
+       private->vol_updated = 1;
+
+       if (!info->line_out_hw_vol)
+               return;
+
+       for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->dim_mute_ctls[i]->id);
+
+       for (i = 0; i < num_line_out; i++)
+               if (private->vol_sw_hw_switch[line_out_remap(private, i)])
+                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                                      &private->mute_ctls[i]->id);
+}
+
+/* Notify on "input other" change (level/pad/air) */
+static void scarlett2_notify_input_other(
+       struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       int i;
+
+       private->input_other_updated = 1;
+
+       for (i = 0; i < info->level_input_count; i++)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->level_ctls[i]->id);
+       for (i = 0; i < info->pad_input_count; i++)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->pad_ctls[i]->id);
+       for (i = 0; i < info->air_input_count; i++)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->air_ctls[i]->id);
+       for (i = 0; i < info->phantom_count; i++)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->phantom_ctls[i]->id);
+}
+
+/* Notify on "monitor other" change (direct monitor, speaker
+ * switching, talkback)
+ */
+static void scarlett2_notify_monitor_other(
+       struct usb_mixer_interface *mixer)
+{
+       struct snd_card *card = mixer->chip->card;
+       struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+
+       private->monitor_other_updated = 1;
+
+       if (info->direct_monitor) {
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->direct_monitor_ctl->id);
+               return;
+       }
+
+       if (info->has_speaker_switching)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->speaker_switching_ctl->id);
+
+       if (info->has_talkback)
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                              &private->talkback_ctl->id);
+
+       /* if speaker switching was recently enabled or disabled,
+        * invalidate the dim/mute and mux enum controls
+        */
+       if (private->speaker_switching_switched) {
+               int i;
+
+               scarlett2_notify_dim_mute(mixer);
+
+               private->speaker_switching_switched = 0;
+               private->mux_updated = 1;
+
+               for (i = 0; i < private->num_mux_dsts; i++)
+                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                                      &private->mux_ctls[i]->id);
+       }
+}
+
+/* Interrupt callback */
+static void scarlett2_notify(struct urb *urb)
+{
+       struct usb_mixer_interface *mixer = urb->context;
+       int len = urb->actual_length;
+       int ustatus = urb->status;
+       u32 data;
+
+       if (ustatus != 0 || len != 8)
+               goto requeue;
+
+       data = le32_to_cpu(*(__le32 *)urb->transfer_buffer);
+       if (data & SCARLETT2_USB_NOTIFY_SYNC)
+               scarlett2_notify_sync(mixer);
+       if (data & SCARLETT2_USB_NOTIFY_MONITOR)
+               scarlett2_notify_monitor(mixer);
+       if (data & SCARLETT2_USB_NOTIFY_DIM_MUTE)
+               scarlett2_notify_dim_mute(mixer);
+       if (data & SCARLETT2_USB_NOTIFY_INPUT_OTHER)
+               scarlett2_notify_input_other(mixer);
+       if (data & SCARLETT2_USB_NOTIFY_MONITOR_OTHER)
+               scarlett2_notify_monitor_other(mixer);
+
+requeue:
+       if (ustatus != -ENOENT &&
+           ustatus != -ECONNRESET &&
+           ustatus != -ESHUTDOWN) {
+               urb->dev = mixer->chip->dev;
+               usb_submit_urb(urb, GFP_ATOMIC);
+       }
+}
+
+static int scarlett2_init_notify(struct usb_mixer_interface *mixer)
+{
+       struct usb_device *dev = mixer->chip->dev;
+       struct scarlett2_data *private = mixer->private_data;
+       unsigned int pipe = usb_rcvintpipe(dev, private->bEndpointAddress);
+       void *transfer_buffer;
+
+       if (mixer->urb) {
+               usb_audio_err(mixer->chip,
+                             "%s: mixer urb already in use!\n", __func__);
+               return 0;
+       }
+
+       if (usb_pipe_type_check(dev, pipe))
+               return -EINVAL;
+
+       mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
+       if (!mixer->urb)
+               return -ENOMEM;
+
+       transfer_buffer = kmalloc(private->wMaxPacketSize, GFP_KERNEL);
+       if (!transfer_buffer)
+               return -ENOMEM;
+
+       usb_fill_int_urb(mixer->urb, dev, pipe,
+                        transfer_buffer, private->wMaxPacketSize,
+                        scarlett2_notify, mixer, private->bInterval);
+
+       return usb_submit_urb(mixer->urb, GFP_KERNEL);
+}
+
+static const struct scarlett2_device_entry *get_scarlett2_device_entry(
+       struct usb_mixer_interface *mixer)
+{
+       const struct scarlett2_device_entry *entry = scarlett2_devices;
+
+       /* Find entry in scarlett2_devices */
+       while (entry->usb_id && entry->usb_id != mixer->chip->usb_id)
+               entry++;
+       if (!entry->usb_id)
+               return NULL;
+
+       return entry;
+}
+
+static int snd_scarlett2_controls_create(
+       struct usb_mixer_interface *mixer,
+       const struct scarlett2_device_entry *entry)
+{
+       int err;
+
+       /* Initialise private data */
+       err = scarlett2_init_private(mixer, entry);
+       if (err < 0)
+               return err;
+
+       /* Send proprietary USB initialisation sequence */
+       err = scarlett2_usb_init(mixer);
+       if (err < 0)
+               return err;
+
+       /* Read volume levels and controls from the interface */
+       err = scarlett2_read_configs(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the MSD control */
+       err = scarlett2_add_msd_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* If MSD mode is enabled, don't create any other controls */
+       if (((struct scarlett2_data *)mixer->private_data)->msd_switch)
+               return 0;
+
+       /* Create the analogue output controls */
+       err = scarlett2_add_line_out_ctls(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the analogue input controls */
+       err = scarlett2_add_line_in_ctls(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the input, output, and mixer mux input selections */
+       err = scarlett2_add_mux_enums(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the matrix mixer controls */
+       err = scarlett2_add_mixer_ctls(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the level meter controls */
+       err = scarlett2_add_meter_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the sync control */
+       err = scarlett2_add_sync_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the direct monitor control */
+       err = scarlett2_add_direct_monitor_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the speaker switching control */
+       err = scarlett2_add_speaker_switch_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the talkback controls */
+       err = scarlett2_add_talkback_ctls(mixer);
+       if (err < 0)
+               return err;
+
+       /* Create the standalone control */
+       err = scarlett2_add_standalone_ctl(mixer);
+       if (err < 0)
+               return err;
+
+       /* Set up the interrupt polling */
+       err = scarlett2_init_notify(mixer);
+       if (err < 0)
+               return err;
+
+       return 0;
+}
+
+int snd_scarlett2_init(struct usb_mixer_interface *mixer)
+{
+       struct snd_usb_audio *chip = mixer->chip;
+       const struct scarlett2_device_entry *entry;
+       int err;
+
+       /* only use UAC_VERSION_2 */
+       if (!mixer->protocol)
+               return 0;
+
+       /* find entry in scarlett2_devices */
+       entry = get_scarlett2_device_entry(mixer);
+       if (!entry) {
+               usb_audio_err(mixer->chip,
+                             "%s: missing device entry for %04x:%04x\n",
+                             __func__,
+                             USB_ID_VENDOR(chip->usb_id),
+                             USB_ID_PRODUCT(chip->usb_id));
+               return 0;
+       }
+
+       if (chip->setup & SCARLETT2_DISABLE) {
+               usb_audio_info(chip,
+                       "Focusrite %s Mixer Driver disabled "
+                       "by modprobe options (snd_usb_audio "
+                       "vid=0x%04x pid=0x%04x device_setup=%d)\n",
+                       entry->series_name,
+                       USB_ID_VENDOR(chip->usb_id),
+                       USB_ID_PRODUCT(chip->usb_id),
+                       SCARLETT2_DISABLE);
+               return 0;
+       }
+
+       usb_audio_info(chip,
+               "Focusrite %s Mixer Driver enabled (pid=0x%04x); "
+               "report any issues to g@b4.vu",
+               entry->series_name,
+               USB_ID_PRODUCT(chip->usb_id));
+
+       err = snd_scarlett2_controls_create(mixer, entry);
+       if (err < 0)
+               usb_audio_err(mixer->chip,
+                             "Error initialising %s Mixer Driver: %d",
+                             entry->series_name,
+                             err);
+
+       return err;
+}
diff --git a/sound/usb/mixer_scarlett2.h b/sound/usb/mixer_scarlett2.h
new file mode 100644 (file)
index 0000000..d209362
--- /dev/null
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_MIXER_SCARLETT2_H
+#define __USB_MIXER_SCARLETT2_H
+
+int snd_scarlett2_init(struct usb_mixer_interface *mixer);
+
+#endif /* __USB_MIXER_SCARLETT2_H */
diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c
deleted file mode 100644 (file)
index 7c86538..0000000
+++ /dev/null
@@ -1,4312 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *   Focusrite Scarlett Gen 2/3 and Clarett USB/Clarett+ Driver for ALSA
- *
- *   Supported models:
- *   - 6i6/18i8/18i20 Gen 2
- *   - Solo/2i2/4i4/8i6/18i8/18i20 Gen 3
- *   - Clarett 2Pre/4Pre/8Pre USB
- *   - Clarett+ 2Pre/4Pre/8Pre
- *
- *   Copyright (c) 2018-2023 by Geoffrey D. Bennett <g at b4.vu>
- *   Copyright (c) 2020-2021 by Vladimir Sadovnikov <sadko4u@gmail.com>
- *   Copyright (c) 2022 by Christian Colglazier <christian@cacolglazier.com>
- *
- *   Based on the Scarlett (Gen 1) Driver for ALSA:
- *
- *   Copyright (c) 2013 by Tobias Hoffmann
- *   Copyright (c) 2013 by Robin Gareus <robin at gareus.org>
- *   Copyright (c) 2002 by Takashi Iwai <tiwai at suse.de>
- *   Copyright (c) 2014 by Chris J Arges <chris.j.arges at canonical.com>
- *
- *   Many codes borrowed from audio.c by
- *     Alan Cox (alan at lxorguk.ukuu.org.uk)
- *     Thomas Sailer (sailer at ife.ee.ethz.ch)
- *
- *   Code cleanup:
- *   David Henningsson <david.henningsson at canonical.com>
- */
-
-/* The protocol was reverse engineered by looking at the communication
- * between Focusrite Control 2.3.4 and the Focusrite(R) Scarlett 18i20
- * (firmware 1083) using usbmon in July-August 2018.
- *
- * Scarlett 18i8 support added in April 2019.
- *
- * Scarlett 6i6 support added in June 2019 (thanks to Martin Wittmann
- * for providing usbmon output and testing).
- *
- * Scarlett 4i4/8i6 Gen 3 support added in May 2020 (thanks to Laurent
- * Debricon for donating a 4i4 and to Fredrik Unger for providing 8i6
- * usbmon output and testing).
- *
- * Scarlett 18i8/18i20 Gen 3 support added in June 2020 (thanks to
- * Darren Jaeckel, Alex Sedlack, and Clovis Lunel for providing usbmon
- * output, protocol traces and testing).
- *
- * Support for loading mixer volume and mux configuration from the
- * interface during driver initialisation added in May 2021 (thanks to
- * Vladimir Sadovnikov for figuring out how).
- *
- * Support for Solo/2i2 Gen 3 added in May 2021 (thanks to Alexander
- * Vorona for 2i2 protocol traces).
- *
- * Support for phantom power, direct monitoring, speaker switching,
- * and talkback added in May-June 2021.
- *
- * Support for Clarett+ 8Pre added in Aug 2022 by Christian
- * Colglazier.
- *
- * Support for Clarett 8Pre USB added in Sep 2023 (thanks to Philippe
- * Perrot for confirmation).
- *
- * Support for Clarett+ 4Pre and 2Pre added in Sep 2023 (thanks to
- * Gregory Rozzo for donating a 4Pre, and David Sherwood and Patrice
- * Peterson for usbmon output).
- *
- * Support for Clarett 2Pre and 4Pre USB added in Oct 2023.
- *
- * This ALSA mixer gives access to (model-dependent):
- *  - input, output, mixer-matrix muxes
- *  - mixer-matrix gain stages
- *  - gain/volume/mute controls
- *  - level meters
- *  - line/inst level, pad, and air controls
- *  - phantom power, direct monitor, speaker switching, and talkback
- *    controls
- *  - disable/enable MSD mode
- *  - disable/enable standalone mode
- *
- * <ditaa>
- *    /--------------\    18chn            20chn     /--------------\
- *    | Hardware  in +--+------\    /-------------+--+ ALSA PCM out |
- *    \--------------/  |      |    |             |  \--------------/
- *                      |      |    |    /-----\  |
- *                      |      |    |    |     |  |
- *                      |      v    v    v     |  |
- *                      |   +---------------+  |  |
- *                      |    \ Matrix  Mux /   |  |
- *                      |     +-----+-----+    |  |
- *                      |           |          |  |
- *                      |           |18chn     |  |
- *                      |           |          |  |
- *                      |           |     10chn|  |
- *                      |           v          |  |
- *                      |     +------------+   |  |
- *                      |     | Mixer      |   |  |
- *                      |     |     Matrix |   |  |
- *                      |     |            |   |  |
- *                      |     | 18x10 Gain |   |  |
- *                      |     |   stages   |   |  |
- *                      |     +-----+------+   |  |
- *                      |           |          |  |
- *                      |18chn      |10chn     |  |20chn
- *                      |           |          |  |
- *                      |           +----------/  |
- *                      |           |             |
- *                      v           v             v
- *                      ===========================
- *               +---------------+       +--—------------+
- *                \ Output  Mux /         \ Capture Mux /
- *                 +---+---+---+           +-----+-----+
- *                     |   |                     |
- *                10chn|   |                     |18chn
- *                     |   |                     |
- *  /--------------\   |   |                     |   /--------------\
- *  | S/PDIF, ADAT |<--/   |10chn                \-->| ALSA PCM in  |
- *  | Hardware out |       |                         \--------------/
- *  \--------------/       |
- *                         v
- *                  +-------------+    Software gain per channel.
- *                  | Master Gain |<-- 18i20 only: Switch per channel
- *                  +------+------+    to select HW or SW gain control.
- *                         |
- *                         |10chn
- *  /--------------\       |
- *  | Analogue     |<------/
- *  | Hardware out |
- *  \--------------/
- * </ditaa>
- *
- * Gen 3 devices have a Mass Storage Device (MSD) mode where a small
- * disk with registration and driver download information is presented
- * to the host. To access the full functionality of the device without
- * proprietary software, MSD mode can be disabled by:
- * - holding down the 48V button for five seconds while powering on
- *   the device, or
- * - using this driver and alsamixer to change the "MSD Mode" setting
- *   to Off and power-cycling the device
- */
-
-#include <linux/slab.h>
-#include <linux/usb.h>
-#include <linux/moduleparam.h>
-
-#include <sound/control.h>
-#include <sound/tlv.h>
-
-#include "usbaudio.h"
-#include "mixer.h"
-#include "helper.h"
-
-#include "mixer_scarlett_gen2.h"
-
-/* device_setup value to allow turning MSD mode back on */
-#define SCARLETT2_MSD_ENABLE 0x02
-
-/* device_setup value to disable this mixer driver */
-#define SCARLETT2_DISABLE 0x04
-
-/* some gui mixers can't handle negative ctl values */
-#define SCARLETT2_VOLUME_BIAS 127
-
-/* mixer range from -80dB to +6dB in 0.5dB steps */
-#define SCARLETT2_MIXER_MIN_DB -80
-#define SCARLETT2_MIXER_BIAS (-SCARLETT2_MIXER_MIN_DB * 2)
-#define SCARLETT2_MIXER_MAX_DB 6
-#define SCARLETT2_MIXER_MAX_VALUE \
-       ((SCARLETT2_MIXER_MAX_DB - SCARLETT2_MIXER_MIN_DB) * 2)
-#define SCARLETT2_MIXER_VALUE_COUNT (SCARLETT2_MIXER_MAX_VALUE + 1)
-
-/* map from (dB + 80) * 2 to mixer value
- * for dB in 0 .. 172: int(8192 * pow(10, ((dB - 160) / 2 / 20)))
- */
-static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
-       0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2,
-       2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 8, 8,
-       9, 9, 10, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
-       23, 24, 25, 27, 29, 30, 32, 34, 36, 38, 41, 43, 46, 48, 51,
-       54, 57, 61, 65, 68, 73, 77, 81, 86, 91, 97, 103, 109, 115,
-       122, 129, 137, 145, 154, 163, 173, 183, 194, 205, 217, 230,
-       244, 259, 274, 290, 307, 326, 345, 365, 387, 410, 434, 460,
-       487, 516, 547, 579, 614, 650, 689, 730, 773, 819, 867, 919,
-       973, 1031, 1092, 1157, 1225, 1298, 1375, 1456, 1543, 1634,
-       1731, 1833, 1942, 2057, 2179, 2308, 2445, 2590, 2744, 2906,
-       3078, 3261, 3454, 3659, 3876, 4105, 4349, 4606, 4879, 5168,
-       5475, 5799, 6143, 6507, 6892, 7301, 7733, 8192, 8677, 9191,
-       9736, 10313, 10924, 11571, 12257, 12983, 13752, 14567, 15430,
-       16345
-};
-
-/* Maximum number of analogue outputs */
-#define SCARLETT2_ANALOGUE_MAX 10
-
-/* Maximum number of level and pad switches */
-#define SCARLETT2_LEVEL_SWITCH_MAX 2
-#define SCARLETT2_PAD_SWITCH_MAX 8
-#define SCARLETT2_AIR_SWITCH_MAX 8
-#define SCARLETT2_PHANTOM_SWITCH_MAX 2
-
-/* Maximum number of inputs to the mixer */
-#define SCARLETT2_INPUT_MIX_MAX 25
-
-/* Maximum number of outputs from the mixer */
-#define SCARLETT2_OUTPUT_MIX_MAX 12
-
-/* Maximum size of the data in the USB mux assignment message:
- * 20 inputs, 20 outputs, 25 matrix inputs, 12 spare
- */
-#define SCARLETT2_MUX_MAX 77
-
-/* Maximum number of meters (sum of output port counts) */
-#define SCARLETT2_MAX_METERS 65
-
-/* There are three different sets of configuration parameters across
- * the devices
- */
-enum {
-       SCARLETT2_CONFIG_SET_NO_MIXER = 0,
-       SCARLETT2_CONFIG_SET_GEN_2 = 1,
-       SCARLETT2_CONFIG_SET_GEN_3 = 2,
-       SCARLETT2_CONFIG_SET_CLARETT = 3,
-       SCARLETT2_CONFIG_SET_COUNT = 4
-};
-
-/* Hardware port types:
- * - None (no input to mux)
- * - Analogue I/O
- * - S/PDIF I/O
- * - ADAT I/O
- * - Mixer I/O
- * - PCM I/O
- */
-enum {
-       SCARLETT2_PORT_TYPE_NONE     = 0,
-       SCARLETT2_PORT_TYPE_ANALOGUE = 1,
-       SCARLETT2_PORT_TYPE_SPDIF    = 2,
-       SCARLETT2_PORT_TYPE_ADAT     = 3,
-       SCARLETT2_PORT_TYPE_MIX      = 4,
-       SCARLETT2_PORT_TYPE_PCM      = 5,
-       SCARLETT2_PORT_TYPE_COUNT    = 6,
-};
-
-/* I/O count of each port type kept in struct scarlett2_ports */
-enum {
-       SCARLETT2_PORT_IN    = 0,
-       SCARLETT2_PORT_OUT   = 1,
-       SCARLETT2_PORT_DIRNS = 2,
-};
-
-/* Dim/Mute buttons on the 18i20 */
-enum {
-       SCARLETT2_BUTTON_MUTE    = 0,
-       SCARLETT2_BUTTON_DIM     = 1,
-       SCARLETT2_DIM_MUTE_COUNT = 2,
-};
-
-static const char *const scarlett2_dim_mute_names[SCARLETT2_DIM_MUTE_COUNT] = {
-       "Mute Playback Switch", "Dim Playback Switch"
-};
-
-/* Description of each hardware port type:
- * - id: hardware ID of this port type
- * - src_descr: printf format string for mux input selections
- * - src_num_offset: added to channel number for the fprintf
- * - dst_descr: printf format string for mixer controls
- */
-struct scarlett2_port {
-       u16 id;
-       const char * const src_descr;
-       int src_num_offset;
-       const char * const dst_descr;
-};
-
-static const struct scarlett2_port scarlett2_ports[SCARLETT2_PORT_TYPE_COUNT] = {
-       [SCARLETT2_PORT_TYPE_NONE] = {
-               .id = 0x000,
-               .src_descr = "Off"
-       },
-       [SCARLETT2_PORT_TYPE_ANALOGUE] = {
-               .id = 0x080,
-               .src_descr = "Analogue %d",
-               .src_num_offset = 1,
-               .dst_descr = "Analogue Output %02d Playback"
-       },
-       [SCARLETT2_PORT_TYPE_SPDIF] = {
-               .id = 0x180,
-               .src_descr = "S/PDIF %d",
-               .src_num_offset = 1,
-               .dst_descr = "S/PDIF Output %d Playback"
-       },
-       [SCARLETT2_PORT_TYPE_ADAT] = {
-               .id = 0x200,
-               .src_descr = "ADAT %d",
-               .src_num_offset = 1,
-               .dst_descr = "ADAT Output %d Playback"
-       },
-       [SCARLETT2_PORT_TYPE_MIX] = {
-               .id = 0x300,
-               .src_descr = "Mix %c",
-               .src_num_offset = 'A',
-               .dst_descr = "Mixer Input %02d Capture"
-       },
-       [SCARLETT2_PORT_TYPE_PCM] = {
-               .id = 0x600,
-               .src_descr = "PCM %d",
-               .src_num_offset = 1,
-               .dst_descr = "PCM %02d Capture"
-       },
-};
-
-/* Number of mux tables: one for each band of sample rates
- * (44.1/48kHz, 88.2/96kHz, and 176.4/176kHz)
- */
-#define SCARLETT2_MUX_TABLES 3
-
-/* Maximum number of entries in a mux table */
-#define SCARLETT2_MAX_MUX_ENTRIES 10
-
-/* One entry within mux_assignment defines the port type and range of
- * ports to add to the set_mux message. The end of the list is marked
- * with count == 0.
- */
-struct scarlett2_mux_entry {
-       u8 port_type;
-       u8 start;
-       u8 count;
-};
-
-struct scarlett2_device_info {
-       /* Gen 3 devices have an internal MSD mode switch that needs
-        * to be disabled in order to access the full functionality of
-        * the device.
-        */
-       u8 has_msd_mode;
-
-       /* which set of configuration parameters the device uses */
-       u8 config_set;
-
-       /* line out hw volume is sw controlled */
-       u8 line_out_hw_vol;
-
-       /* support for main/alt speaker switching */
-       u8 has_speaker_switching;
-
-       /* support for talkback microphone */
-       u8 has_talkback;
-
-       /* the number of analogue inputs with a software switchable
-        * level control that can be set to line or instrument
-        */
-       u8 level_input_count;
-
-       /* the first input with a level control (0-based) */
-       u8 level_input_first;
-
-       /* the number of analogue inputs with a software switchable
-        * 10dB pad control
-        */
-       u8 pad_input_count;
-
-       /* the number of analogue inputs with a software switchable
-        * "air" control
-        */
-       u8 air_input_count;
-
-       /* the number of phantom (48V) software switchable controls */
-       u8 phantom_count;
-
-       /* the number of inputs each phantom switch controls */
-       u8 inputs_per_phantom;
-
-       /* the number of direct monitor options
-        * (0 = none, 1 = mono only, 2 = mono/stereo)
-        */
-       u8 direct_monitor;
-
-       /* remap analogue outputs; 18i8 Gen 3 has "line 3/4" connected
-        * internally to the analogue 7/8 outputs
-        */
-       u8 line_out_remap_enable;
-       u8 line_out_remap[SCARLETT2_ANALOGUE_MAX];
-
-       /* additional description for the line out volume controls */
-       const char * const line_out_descrs[SCARLETT2_ANALOGUE_MAX];
-
-       /* number of sources/destinations of each port type */
-       const int port_count[SCARLETT2_PORT_TYPE_COUNT][SCARLETT2_PORT_DIRNS];
-
-       /* layout/order of the entries in the set_mux message */
-       struct scarlett2_mux_entry mux_assignment[SCARLETT2_MUX_TABLES]
-                                                [SCARLETT2_MAX_MUX_ENTRIES];
-};
-
-struct scarlett2_data {
-       struct usb_mixer_interface *mixer;
-       struct mutex usb_mutex; /* prevent sending concurrent USB requests */
-       struct mutex data_mutex; /* lock access to this data */
-       struct delayed_work work;
-       const struct scarlett2_device_info *info;
-       const char *series_name;
-       __u8 bInterfaceNumber;
-       __u8 bEndpointAddress;
-       __u16 wMaxPacketSize;
-       __u8 bInterval;
-       int num_mux_srcs;
-       int num_mux_dsts;
-       u16 scarlett2_seq;
-       u8 sync_updated;
-       u8 vol_updated;
-       u8 input_other_updated;
-       u8 monitor_other_updated;
-       u8 mux_updated;
-       u8 speaker_switching_switched;
-       u8 sync;
-       u8 master_vol;
-       u8 vol[SCARLETT2_ANALOGUE_MAX];
-       u8 vol_sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
-       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
-       u8 level_switch[SCARLETT2_LEVEL_SWITCH_MAX];
-       u8 pad_switch[SCARLETT2_PAD_SWITCH_MAX];
-       u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
-       u8 air_switch[SCARLETT2_AIR_SWITCH_MAX];
-       u8 phantom_switch[SCARLETT2_PHANTOM_SWITCH_MAX];
-       u8 phantom_persistence;
-       u8 direct_monitor_switch;
-       u8 speaker_switching_switch;
-       u8 talkback_switch;
-       u8 talkback_map[SCARLETT2_OUTPUT_MIX_MAX];
-       u8 msd_switch;
-       u8 standalone_switch;
-       struct snd_kcontrol *sync_ctl;
-       struct snd_kcontrol *master_vol_ctl;
-       struct snd_kcontrol *vol_ctls[SCARLETT2_ANALOGUE_MAX];
-       struct snd_kcontrol *sw_hw_ctls[SCARLETT2_ANALOGUE_MAX];
-       struct snd_kcontrol *mute_ctls[SCARLETT2_ANALOGUE_MAX];
-       struct snd_kcontrol *dim_mute_ctls[SCARLETT2_DIM_MUTE_COUNT];
-       struct snd_kcontrol *level_ctls[SCARLETT2_LEVEL_SWITCH_MAX];
-       struct snd_kcontrol *pad_ctls[SCARLETT2_PAD_SWITCH_MAX];
-       struct snd_kcontrol *air_ctls[SCARLETT2_AIR_SWITCH_MAX];
-       struct snd_kcontrol *phantom_ctls[SCARLETT2_PHANTOM_SWITCH_MAX];
-       struct snd_kcontrol *mux_ctls[SCARLETT2_MUX_MAX];
-       struct snd_kcontrol *direct_monitor_ctl;
-       struct snd_kcontrol *speaker_switching_ctl;
-       struct snd_kcontrol *talkback_ctl;
-       u8 mux[SCARLETT2_MUX_MAX];
-       u8 mix[SCARLETT2_INPUT_MIX_MAX * SCARLETT2_OUTPUT_MIX_MAX];
-};
-
-/*** Model-specific data ***/
-
-static const struct scarlett2_device_info s6i6_gen2_info = {
-       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
-       .level_input_count = 2,
-       .pad_input_count = 2,
-
-       .line_out_descrs = {
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  4,  4 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = {  6,  6 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info s18i8_gen2_info = {
-       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
-       .level_input_count = 2,
-       .pad_input_count = 4,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  6 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 18 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 10 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  4 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info s18i20_gen2_info = {
-       .config_set = SCARLETT2_CONFIG_SET_GEN_2,
-       .line_out_hw_vol = 1,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               NULL,
-               NULL,
-               NULL,
-               NULL,
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8, 10 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 18 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,     0,  8 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,     0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 10 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  6 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info solo_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
-       .level_input_count = 1,
-       .level_input_first = 1,
-       .air_input_count = 1,
-       .phantom_count = 1,
-       .inputs_per_phantom = 1,
-       .direct_monitor = 1,
-};
-
-static const struct scarlett2_device_info s2i2_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
-       .level_input_count = 2,
-       .air_input_count = 2,
-       .phantom_count = 1,
-       .inputs_per_phantom = 2,
-       .direct_monitor = 2,
-};
-
-static const struct scarlett2_device_info s4i4_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
-       .level_input_count = 2,
-       .pad_input_count = 2,
-       .air_input_count = 2,
-       .phantom_count = 1,
-       .inputs_per_phantom = 2,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               "Headphones L",
-               "Headphones R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = { 1, 0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = { 4, 4 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 6, 8 },
-               [SCARLETT2_PORT_TYPE_PCM]      = { 4, 6 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  6 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 16 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info s8i6_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
-       .level_input_count = 2,
-       .pad_input_count = 2,
-       .air_input_count = 2,
-       .phantom_count = 1,
-       .inputs_per_phantom = 2,
-
-       .line_out_descrs = {
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = { 1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = { 6,  4 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = { 2,  2 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 8,  8 },
-               [SCARLETT2_PORT_TYPE_PCM]      = { 6, 10 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_PCM,      8,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0,  8 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 18 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info s18i8_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
-       .line_out_hw_vol = 1,
-       .has_speaker_switching = 1,
-       .level_input_count = 2,
-       .pad_input_count = 4,
-       .air_input_count = 4,
-       .phantom_count = 2,
-       .inputs_per_phantom = 2,
-
-       .line_out_remap_enable = 1,
-       .line_out_remap = { 0, 1, 6, 7, 2, 3, 4, 5 },
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               "Alt Monitor L",
-               "Alt Monitor R",
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  8 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 20 },
-               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 20 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
-               { SCARLETT2_PORT_TYPE_PCM,      12,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_PCM,      10,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
-               { 0,                             0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
-               { SCARLETT2_PORT_TYPE_PCM,      12,  4 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_PCM,      10,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
-               { 0,                             0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  6,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  2,  4 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,       0, 20 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
-               { 0,                             0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info s18i20_gen3_info = {
-       .has_msd_mode = 1,
-       .config_set = SCARLETT2_CONFIG_SET_GEN_3,
-       .line_out_hw_vol = 1,
-       .has_speaker_switching = 1,
-       .has_talkback = 1,
-       .level_input_count = 2,
-       .pad_input_count = 8,
-       .air_input_count = 8,
-       .phantom_count = 2,
-       .inputs_per_phantom = 4,
-
-       .line_out_descrs = {
-               "Monitor 1 L",
-               "Monitor 1 R",
-               "Monitor 2 L",
-               "Monitor 2 R",
-               NULL,
-               NULL,
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  9, 10 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 12, 25 },
-               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 20 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,       0,  8 },
-               { SCARLETT2_PORT_TYPE_PCM,      10, 10 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,      0,  8 },
-               { SCARLETT2_PORT_TYPE_PCM,       8,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,       0, 25 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 12 },
-               { 0,                             0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,       0,  8 },
-               { SCARLETT2_PORT_TYPE_PCM,      10,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,      0,  8 },
-               { SCARLETT2_PORT_TYPE_PCM,       8,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,       0, 25 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 10 },
-               { 0,                             0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,       0, 10 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE,  0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,     0,  2 },
-               { SCARLETT2_PORT_TYPE_NONE,      0, 24 },
-               { 0,                             0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info clarett_2pre_info = {
-       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
-       .line_out_hw_vol = 1,
-       .level_input_count = 2,
-       .air_input_count = 2,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               "Headphones L",
-               "Headphones R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  2,  4 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  0 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = {  4, 12 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  8 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0,  2 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  4 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 26 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info clarett_4pre_info = {
-       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
-       .line_out_hw_vol = 1,
-       .level_input_count = 2,
-       .air_input_count = 4,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8,  6 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  0 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = {  8, 18 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0,  6 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 24 },
-               { 0,                            0,  0 },
-       } },
-};
-
-static const struct scarlett2_device_info clarett_8pre_info = {
-       .config_set = SCARLETT2_CONFIG_SET_CLARETT,
-       .line_out_hw_vol = 1,
-       .level_input_count = 2,
-       .air_input_count = 8,
-
-       .line_out_descrs = {
-               "Monitor L",
-               "Monitor R",
-               NULL,
-               NULL,
-               NULL,
-               NULL,
-               "Headphones 1 L",
-               "Headphones 1 R",
-               "Headphones 2 L",
-               "Headphones 2 R",
-       },
-
-       .port_count = {
-               [SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
-               [SCARLETT2_PORT_TYPE_ANALOGUE] = {  8, 10 },
-               [SCARLETT2_PORT_TYPE_SPDIF]    = {  2,  2 },
-               [SCARLETT2_PORT_TYPE_ADAT]     = {  8,  8 },
-               [SCARLETT2_PORT_TYPE_MIX]      = { 10, 18 },
-               [SCARLETT2_PORT_TYPE_PCM]      = { 20, 18 },
-       },
-
-       .mux_assignment = { {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 18 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,     0,  8 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 14 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_ADAT,     0,  4 },
-               { SCARLETT2_PORT_TYPE_MIX,      0, 18 },
-               { SCARLETT2_PORT_TYPE_NONE,     0,  8 },
-               { 0,                            0,  0 },
-       }, {
-               { SCARLETT2_PORT_TYPE_PCM,      0, 12 },
-               { SCARLETT2_PORT_TYPE_ANALOGUE, 0, 10 },
-               { SCARLETT2_PORT_TYPE_SPDIF,    0,  2 },
-               { SCARLETT2_PORT_TYPE_NONE,     0, 22 },
-               { 0,                            0,  0 },
-       } },
-};
-
-struct scarlett2_device_entry {
-       const u32 usb_id; /* USB device identifier */
-       const struct scarlett2_device_info *info;
-       const char *series_name;
-};
-
-static const struct scarlett2_device_entry scarlett2_devices[] = {
-       /* Supported Gen 2 devices */
-       { USB_ID(0x1235, 0x8203), &s6i6_gen2_info, "Scarlett Gen 2" },
-       { USB_ID(0x1235, 0x8204), &s18i8_gen2_info, "Scarlett Gen 2" },
-       { USB_ID(0x1235, 0x8201), &s18i20_gen2_info, "Scarlett Gen 2" },
-
-       /* Supported Gen 3 devices */
-       { USB_ID(0x1235, 0x8211), &solo_gen3_info, "Scarlett Gen 3" },
-       { USB_ID(0x1235, 0x8210), &s2i2_gen3_info, "Scarlett Gen 3" },
-       { USB_ID(0x1235, 0x8212), &s4i4_gen3_info, "Scarlett Gen 3" },
-       { USB_ID(0x1235, 0x8213), &s8i6_gen3_info, "Scarlett Gen 3" },
-       { USB_ID(0x1235, 0x8214), &s18i8_gen3_info, "Scarlett Gen 3" },
-       { USB_ID(0x1235, 0x8215), &s18i20_gen3_info, "Scarlett Gen 3" },
-
-       /* Supported Clarett USB/Clarett+ devices */
-       { USB_ID(0x1235, 0x8206), &clarett_2pre_info, "Clarett USB" },
-       { USB_ID(0x1235, 0x8207), &clarett_4pre_info, "Clarett USB" },
-       { USB_ID(0x1235, 0x8208), &clarett_8pre_info, "Clarett USB" },
-       { USB_ID(0x1235, 0x820a), &clarett_2pre_info, "Clarett+" },
-       { USB_ID(0x1235, 0x820b), &clarett_4pre_info, "Clarett+" },
-       { USB_ID(0x1235, 0x820c), &clarett_8pre_info, "Clarett+" },
-
-       /* End of list */
-       { 0, NULL },
-};
-
-/* get the starting port index number for a given port type/direction */
-static int scarlett2_get_port_start_num(
-       const int port_count[][SCARLETT2_PORT_DIRNS],
-       int direction, int port_type)
-{
-       int i, num = 0;
-
-       for (i = 0; i < port_type; i++)
-               num += port_count[i][direction];
-
-       return num;
-}
-
-/*** USB Interactions ***/
-
-/* Notifications from the interface */
-#define SCARLETT2_USB_NOTIFY_SYNC          0x00000008
-#define SCARLETT2_USB_NOTIFY_DIM_MUTE      0x00200000
-#define SCARLETT2_USB_NOTIFY_MONITOR       0x00400000
-#define SCARLETT2_USB_NOTIFY_INPUT_OTHER   0x00800000
-#define SCARLETT2_USB_NOTIFY_MONITOR_OTHER 0x01000000
-
-/* Commands for sending/receiving requests/responses */
-#define SCARLETT2_USB_CMD_INIT 0
-#define SCARLETT2_USB_CMD_REQ  2
-#define SCARLETT2_USB_CMD_RESP 3
-
-#define SCARLETT2_USB_INIT_1    0x00000000
-#define SCARLETT2_USB_INIT_2    0x00000002
-#define SCARLETT2_USB_GET_METER 0x00001001
-#define SCARLETT2_USB_GET_MIX   0x00002001
-#define SCARLETT2_USB_SET_MIX   0x00002002
-#define SCARLETT2_USB_GET_MUX   0x00003001
-#define SCARLETT2_USB_SET_MUX   0x00003002
-#define SCARLETT2_USB_GET_SYNC  0x00006004
-#define SCARLETT2_USB_GET_DATA  0x00800000
-#define SCARLETT2_USB_SET_DATA  0x00800001
-#define SCARLETT2_USB_DATA_CMD  0x00800002
-
-#define SCARLETT2_USB_CONFIG_SAVE 6
-
-#define SCARLETT2_USB_VOLUME_STATUS_OFFSET 0x31
-#define SCARLETT2_USB_METER_LEVELS_GET_MAGIC 1
-
-/* volume status is read together (matches scarlett2_config_items[1]) */
-struct scarlett2_usb_volume_status {
-       /* dim/mute buttons */
-       u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
-
-       u8 pad1;
-
-       /* software volume setting */
-       s16 sw_vol[SCARLETT2_ANALOGUE_MAX];
-
-       /* actual volume of output inc. dim (-18dB) */
-       s16 hw_vol[SCARLETT2_ANALOGUE_MAX];
-
-       /* internal mute buttons */
-       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
-
-       /* sw (0) or hw (1) controlled */
-       u8 sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
-
-       u8 pad3[6];
-
-       /* front panel volume knob */
-       s16 master_vol;
-} __packed;
-
-/* Configuration parameters that can be read and written */
-enum {
-       SCARLETT2_CONFIG_DIM_MUTE = 0,
-       SCARLETT2_CONFIG_LINE_OUT_VOLUME = 1,
-       SCARLETT2_CONFIG_MUTE_SWITCH = 2,
-       SCARLETT2_CONFIG_SW_HW_SWITCH = 3,
-       SCARLETT2_CONFIG_LEVEL_SWITCH = 4,
-       SCARLETT2_CONFIG_PAD_SWITCH = 5,
-       SCARLETT2_CONFIG_MSD_SWITCH = 6,
-       SCARLETT2_CONFIG_AIR_SWITCH = 7,
-       SCARLETT2_CONFIG_STANDALONE_SWITCH = 8,
-       SCARLETT2_CONFIG_PHANTOM_SWITCH = 9,
-       SCARLETT2_CONFIG_PHANTOM_PERSISTENCE = 10,
-       SCARLETT2_CONFIG_DIRECT_MONITOR = 11,
-       SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH = 12,
-       SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE = 13,
-       SCARLETT2_CONFIG_TALKBACK_MAP = 14,
-       SCARLETT2_CONFIG_COUNT = 15
-};
-
-/* Location, size, and activation command number for the configuration
- * parameters. Size is in bits and may be 1, 8, or 16.
- */
-struct scarlett2_config {
-       u8 offset;
-       u8 size;
-       u8 activate;
-};
-
-static const struct scarlett2_config
-       scarlett2_config_items[SCARLETT2_CONFIG_SET_COUNT]
-                             [SCARLETT2_CONFIG_COUNT] =
-
-/* Devices without a mixer (Gen 3 Solo and 2i2) */
-{ {
-       [SCARLETT2_CONFIG_MSD_SWITCH] = {
-               .offset = 0x04, .size = 8, .activate = 6 },
-
-       [SCARLETT2_CONFIG_PHANTOM_PERSISTENCE] = {
-               .offset = 0x05, .size = 8, .activate = 6 },
-
-       [SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
-               .offset = 0x06, .size = 8, .activate = 3 },
-
-       [SCARLETT2_CONFIG_DIRECT_MONITOR] = {
-               .offset = 0x07, .size = 8, .activate = 4 },
-
-       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-               .offset = 0x08, .size = 1, .activate = 7 },
-
-       [SCARLETT2_CONFIG_AIR_SWITCH] = {
-               .offset = 0x09, .size = 1, .activate = 8 },
-
-/* Gen 2 devices: 6i6, 18i8, 18i20 */
-}, {
-       [SCARLETT2_CONFIG_DIM_MUTE] = {
-               .offset = 0x31, .size = 8, .activate = 2 },
-
-       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
-               .offset = 0x34, .size = 16, .activate = 1 },
-
-       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
-               .offset = 0x5c, .size = 8, .activate = 1 },
-
-       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
-               .offset = 0x66, .size = 8, .activate = 3 },
-
-       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-               .offset = 0x7c, .size = 8, .activate = 7 },
-
-       [SCARLETT2_CONFIG_PAD_SWITCH] = {
-               .offset = 0x84, .size = 8, .activate = 8 },
-
-       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
-               .offset = 0x8d, .size = 8, .activate = 6 },
-
-/* Gen 3 devices: 4i4, 8i6, 18i8, 18i20 */
-}, {
-       [SCARLETT2_CONFIG_DIM_MUTE] = {
-               .offset = 0x31, .size = 8, .activate = 2 },
-
-       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
-               .offset = 0x34, .size = 16, .activate = 1 },
-
-       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
-               .offset = 0x5c, .size = 8, .activate = 1 },
-
-       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
-               .offset = 0x66, .size = 8, .activate = 3 },
-
-       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-               .offset = 0x7c, .size = 8, .activate = 7 },
-
-       [SCARLETT2_CONFIG_PAD_SWITCH] = {
-               .offset = 0x84, .size = 8, .activate = 8 },
-
-       [SCARLETT2_CONFIG_AIR_SWITCH] = {
-               .offset = 0x8c, .size = 8, .activate = 8 },
-
-       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
-               .offset = 0x95, .size = 8, .activate = 6 },
-
-       [SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
-               .offset = 0x9c, .size = 1, .activate = 8 },
-
-       [SCARLETT2_CONFIG_MSD_SWITCH] = {
-               .offset = 0x9d, .size = 8, .activate = 6 },
-
-       [SCARLETT2_CONFIG_PHANTOM_PERSISTENCE] = {
-               .offset = 0x9e, .size = 8, .activate = 6 },
-
-       [SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH] = {
-               .offset = 0x9f, .size = 1, .activate = 10 },
-
-       [SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE] = {
-               .offset = 0xa0, .size = 1, .activate = 10 },
-
-       [SCARLETT2_CONFIG_TALKBACK_MAP] = {
-               .offset = 0xb0, .size = 16, .activate = 10 },
-
-/* Clarett USB and Clarett+ devices: 2Pre, 4Pre, 8Pre */
-}, {
-       [SCARLETT2_CONFIG_DIM_MUTE] = {
-               .offset = 0x31, .size = 8, .activate = 2 },
-
-       [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
-               .offset = 0x34, .size = 16, .activate = 1 },
-
-       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
-               .offset = 0x5c, .size = 8, .activate = 1 },
-
-       [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
-               .offset = 0x66, .size = 8, .activate = 3 },
-
-       [SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-               .offset = 0x7c, .size = 8, .activate = 7 },
-
-       [SCARLETT2_CONFIG_AIR_SWITCH] = {
-               .offset = 0x95, .size = 8, .activate = 8 },
-
-       [SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
-               .offset = 0x8d, .size = 8, .activate = 6 },
-} };
-
-/* proprietary request/response format */
-struct scarlett2_usb_packet {
-       __le32 cmd;
-       __le16 size;
-       __le16 seq;
-       __le32 error;
-       __le32 pad;
-       u8 data[];
-};
-
-static void scarlett2_fill_request_header(struct scarlett2_data *private,
-                                         struct scarlett2_usb_packet *req,
-                                         u32 cmd, u16 req_size)
-{
-       /* sequence must go up by 1 for each request */
-       u16 seq = private->scarlett2_seq++;
-
-       req->cmd = cpu_to_le32(cmd);
-       req->size = cpu_to_le16(req_size);
-       req->seq = cpu_to_le16(seq);
-       req->error = 0;
-       req->pad = 0;
-}
-
-static int scarlett2_usb_tx(struct usb_device *dev, int interface,
-                           void *buf, u16 size)
-{
-       return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
-                       SCARLETT2_USB_CMD_REQ,
-                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
-                       0, interface, buf, size);
-}
-
-static int scarlett2_usb_rx(struct usb_device *dev, int interface,
-                           u32 usb_req, void *buf, u16 size)
-{
-       return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
-                       usb_req,
-                       USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                       0, interface, buf, size);
-}
-
-/* Send a proprietary format request to the Scarlett interface */
-static int scarlett2_usb(
-       struct usb_mixer_interface *mixer, u32 cmd,
-       void *req_data, u16 req_size, void *resp_data, u16 resp_size)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       struct usb_device *dev = mixer->chip->dev;
-       struct scarlett2_usb_packet *req, *resp = NULL;
-       size_t req_buf_size = struct_size(req, data, req_size);
-       size_t resp_buf_size = struct_size(resp, data, resp_size);
-       int err;
-
-       req = kmalloc(req_buf_size, GFP_KERNEL);
-       if (!req) {
-               err = -ENOMEM;
-               goto error;
-       }
-
-       resp = kmalloc(resp_buf_size, GFP_KERNEL);
-       if (!resp) {
-               err = -ENOMEM;
-               goto error;
-       }
-
-       mutex_lock(&private->usb_mutex);
-
-       /* build request message and send it */
-
-       scarlett2_fill_request_header(private, req, cmd, req_size);
-
-       if (req_size)
-               memcpy(req->data, req_data, req_size);
-
-       err = scarlett2_usb_tx(dev, private->bInterfaceNumber,
-                              req, req_buf_size);
-
-       if (err != req_buf_size) {
-               usb_audio_err(
-                       mixer->chip,
-                       "%s USB request result cmd %x was %d\n",
-                       private->series_name, cmd, err);
-               err = -EINVAL;
-               goto unlock;
-       }
-
-       /* send a second message to get the response */
-
-       err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
-                              SCARLETT2_USB_CMD_RESP,
-                              resp, resp_buf_size);
-
-       /* validate the response */
-
-       if (err != resp_buf_size) {
-               usb_audio_err(
-                       mixer->chip,
-                       "%s USB response result cmd %x was %d expected %zu\n",
-                       private->series_name, cmd, err, resp_buf_size);
-               err = -EINVAL;
-               goto unlock;
-       }
-
-       /* cmd/seq/size should match except when initialising
-        * seq sent = 1, response = 0
-        */
-       if (resp->cmd != req->cmd ||
-           (resp->seq != req->seq &&
-               (le16_to_cpu(req->seq) != 1 || resp->seq != 0)) ||
-           resp_size != le16_to_cpu(resp->size) ||
-           resp->error ||
-           resp->pad) {
-               usb_audio_err(
-                       mixer->chip,
-                       "%s USB invalid response; "
-                          "cmd tx/rx %d/%d seq %d/%d size %d/%d "
-                          "error %d pad %d\n",
-                       private->series_name,
-                       le32_to_cpu(req->cmd), le32_to_cpu(resp->cmd),
-                       le16_to_cpu(req->seq), le16_to_cpu(resp->seq),
-                       resp_size, le16_to_cpu(resp->size),
-                       le32_to_cpu(resp->error),
-                       le32_to_cpu(resp->pad));
-               err = -EINVAL;
-               goto unlock;
-       }
-
-       if (resp_data && resp_size > 0)
-               memcpy(resp_data, resp->data, resp_size);
-
-unlock:
-       mutex_unlock(&private->usb_mutex);
-error:
-       kfree(req);
-       kfree(resp);
-       return err;
-}
-
-/* Send a USB message to get data; result placed in *buf */
-static int scarlett2_usb_get(
-       struct usb_mixer_interface *mixer,
-       int offset, void *buf, int size)
-{
-       struct {
-               __le32 offset;
-               __le32 size;
-       } __packed req;
-
-       req.offset = cpu_to_le32(offset);
-       req.size = cpu_to_le32(size);
-       return scarlett2_usb(mixer, SCARLETT2_USB_GET_DATA,
-                            &req, sizeof(req), buf, size);
-}
-
-/* Send a USB message to get configuration parameters; result placed in *buf */
-static int scarlett2_usb_get_config(
-       struct usb_mixer_interface *mixer,
-       int config_item_num, int count, void *buf)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const struct scarlett2_config *config_item =
-               &scarlett2_config_items[info->config_set][config_item_num];
-       int size, err, i;
-       u8 *buf_8;
-       u8 value;
-
-       /* For byte-sized parameters, retrieve directly into buf */
-       if (config_item->size >= 8) {
-               size = config_item->size / 8 * count;
-               err = scarlett2_usb_get(mixer, config_item->offset, buf, size);
-               if (err < 0)
-                       return err;
-               if (size == 2) {
-                       u16 *buf_16 = buf;
-
-                       for (i = 0; i < count; i++, buf_16++)
-                               *buf_16 = le16_to_cpu(*(__le16 *)buf_16);
-               }
-               return 0;
-       }
-
-       /* For bit-sized parameters, retrieve into value */
-       err = scarlett2_usb_get(mixer, config_item->offset, &value, 1);
-       if (err < 0)
-               return err;
-
-       /* then unpack from value into buf[] */
-       buf_8 = buf;
-       for (i = 0; i < 8 && i < count; i++, value >>= 1)
-               *buf_8++ = value & 1;
-
-       return 0;
-}
-
-/* Send SCARLETT2_USB_DATA_CMD SCARLETT2_USB_CONFIG_SAVE */
-static void scarlett2_config_save(struct usb_mixer_interface *mixer)
-{
-       __le32 req = cpu_to_le32(SCARLETT2_USB_CONFIG_SAVE);
-
-       scarlett2_usb(mixer, SCARLETT2_USB_DATA_CMD,
-                     &req, sizeof(u32),
-                     NULL, 0);
-}
-
-/* Delayed work to save config */
-static void scarlett2_config_save_work(struct work_struct *work)
-{
-       struct scarlett2_data *private =
-               container_of(work, struct scarlett2_data, work.work);
-
-       scarlett2_config_save(private->mixer);
-}
-
-/* Send a USB message to set a SCARLETT2_CONFIG_* parameter */
-static int scarlett2_usb_set_config(
-       struct usb_mixer_interface *mixer,
-       int config_item_num, int index, int value)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const struct scarlett2_config *config_item =
-              &scarlett2_config_items[info->config_set][config_item_num];
-       struct {
-               __le32 offset;
-               __le32 bytes;
-               __le32 value;
-       } __packed req;
-       __le32 req2;
-       int offset, size;
-       int err;
-
-       /* Cancel any pending NVRAM save */
-       cancel_delayed_work_sync(&private->work);
-
-       /* Convert config_item->size in bits to size in bytes and
-        * calculate offset
-        */
-       if (config_item->size >= 8) {
-               size = config_item->size / 8;
-               offset = config_item->offset + index * size;
-
-       /* If updating a bit, retrieve the old value, set/clear the
-        * bit as needed, and update value
-        */
-       } else {
-               u8 tmp;
-
-               size = 1;
-               offset = config_item->offset;
-
-               scarlett2_usb_get(mixer, offset, &tmp, 1);
-               if (value)
-                       tmp |= (1 << index);
-               else
-                       tmp &= ~(1 << index);
-
-               value = tmp;
-       }
-
-       /* Send the configuration parameter data */
-       req.offset = cpu_to_le32(offset);
-       req.bytes = cpu_to_le32(size);
-       req.value = cpu_to_le32(value);
-       err = scarlett2_usb(mixer, SCARLETT2_USB_SET_DATA,
-                           &req, sizeof(u32) * 2 + size,
-                           NULL, 0);
-       if (err < 0)
-               return err;
-
-       /* Activate the change */
-       req2 = cpu_to_le32(config_item->activate);
-       err = scarlett2_usb(mixer, SCARLETT2_USB_DATA_CMD,
-                           &req2, sizeof(req2), NULL, 0);
-       if (err < 0)
-               return err;
-
-       /* Schedule the change to be written to NVRAM */
-       if (config_item->activate != SCARLETT2_USB_CONFIG_SAVE)
-               schedule_delayed_work(&private->work, msecs_to_jiffies(2000));
-
-       return 0;
-}
-
-/* Send a USB message to get sync status; result placed in *sync */
-static int scarlett2_usb_get_sync_status(
-       struct usb_mixer_interface *mixer,
-       u8 *sync)
-{
-       __le32 data;
-       int err;
-
-       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_SYNC,
-                           NULL, 0, &data, sizeof(data));
-       if (err < 0)
-               return err;
-
-       *sync = !!data;
-       return 0;
-}
-
-/* Send a USB message to get volume status; result placed in *buf */
-static int scarlett2_usb_get_volume_status(
-       struct usb_mixer_interface *mixer,
-       struct scarlett2_usb_volume_status *buf)
-{
-       return scarlett2_usb_get(mixer, SCARLETT2_USB_VOLUME_STATUS_OFFSET,
-                                buf, sizeof(*buf));
-}
-
-/* Send a USB message to get the volumes for all inputs of one mix
- * and put the values into private->mix[]
- */
-static int scarlett2_usb_get_mix(struct usb_mixer_interface *mixer,
-                                int mix_num)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       int num_mixer_in =
-               info->port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
-       int err, i, j, k;
-
-       struct {
-               __le16 mix_num;
-               __le16 count;
-       } __packed req;
-
-       __le16 data[SCARLETT2_INPUT_MIX_MAX];
-
-       req.mix_num = cpu_to_le16(mix_num);
-       req.count = cpu_to_le16(num_mixer_in);
-
-       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_MIX,
-                           &req, sizeof(req),
-                           data, num_mixer_in * sizeof(u16));
-       if (err < 0)
-               return err;
-
-       for (i = 0, j = mix_num * num_mixer_in; i < num_mixer_in; i++, j++) {
-               u16 mixer_value = le16_to_cpu(data[i]);
-
-               for (k = 0; k < SCARLETT2_MIXER_VALUE_COUNT; k++)
-                       if (scarlett2_mixer_values[k] >= mixer_value)
-                               break;
-               if (k == SCARLETT2_MIXER_VALUE_COUNT)
-                       k = SCARLETT2_MIXER_MAX_VALUE;
-               private->mix[j] = k;
-       }
-
-       return 0;
-}
-
-/* Send a USB message to set the volumes for all inputs of one mix
- * (values obtained from private->mix[])
- */
-static int scarlett2_usb_set_mix(struct usb_mixer_interface *mixer,
-                                int mix_num)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       struct {
-               __le16 mix_num;
-               __le16 data[SCARLETT2_INPUT_MIX_MAX];
-       } __packed req;
-
-       int i, j;
-       int num_mixer_in =
-               info->port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
-
-       req.mix_num = cpu_to_le16(mix_num);
-
-       for (i = 0, j = mix_num * num_mixer_in; i < num_mixer_in; i++, j++)
-               req.data[i] = cpu_to_le16(
-                       scarlett2_mixer_values[private->mix[j]]
-               );
-
-       return scarlett2_usb(mixer, SCARLETT2_USB_SET_MIX,
-                            &req, (num_mixer_in + 1) * sizeof(u16),
-                            NULL, 0);
-}
-
-/* Convert a port number index (per info->port_count) to a hardware ID */
-static u32 scarlett2_mux_src_num_to_id(
-       const int port_count[][SCARLETT2_PORT_DIRNS], int num)
-{
-       int port_type;
-
-       for (port_type = 0;
-            port_type < SCARLETT2_PORT_TYPE_COUNT;
-            port_type++) {
-               if (num < port_count[port_type][SCARLETT2_PORT_IN])
-                       return scarlett2_ports[port_type].id | num;
-               num -= port_count[port_type][SCARLETT2_PORT_IN];
-       }
-
-       /* Oops */
-       return 0;
-}
-
-/* Convert a hardware ID to a port number index */
-static u32 scarlett2_mux_id_to_num(
-       const int port_count[][SCARLETT2_PORT_DIRNS], int direction, u32 id)
-{
-       int port_type;
-       int port_num = 0;
-
-       for (port_type = 0;
-            port_type < SCARLETT2_PORT_TYPE_COUNT;
-            port_type++) {
-               int base = scarlett2_ports[port_type].id;
-               int count = port_count[port_type][direction];
-
-               if (id >= base && id < base + count)
-                       return port_num + id - base;
-               port_num += count;
-       }
-
-       /* Oops */
-       return -1;
-}
-
-/* Convert one mux entry from the interface and load into private->mux[] */
-static void scarlett2_usb_populate_mux(struct scarlett2_data *private,
-                                      u32 mux_entry)
-{
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-
-       int dst_idx, src_idx;
-
-       dst_idx = scarlett2_mux_id_to_num(port_count, SCARLETT2_PORT_OUT,
-                                         mux_entry & 0xFFF);
-       if (dst_idx < 0)
-               return;
-
-       if (dst_idx >= private->num_mux_dsts) {
-               usb_audio_err(private->mixer->chip,
-                       "BUG: scarlett2_mux_id_to_num(%06x, OUT): %d >= %d",
-                       mux_entry, dst_idx, private->num_mux_dsts);
-               return;
-       }
-
-       src_idx = scarlett2_mux_id_to_num(port_count, SCARLETT2_PORT_IN,
-                                         mux_entry >> 12);
-       if (src_idx < 0)
-               return;
-
-       if (src_idx >= private->num_mux_srcs) {
-               usb_audio_err(private->mixer->chip,
-                       "BUG: scarlett2_mux_id_to_num(%06x, IN): %d >= %d",
-                       mux_entry, src_idx, private->num_mux_srcs);
-               return;
-       }
-
-       private->mux[dst_idx] = src_idx;
-}
-
-/* Send USB message to get mux inputs and then populate private->mux[] */
-static int scarlett2_usb_get_mux(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       int count = private->num_mux_dsts;
-       int err, i;
-
-       struct {
-               __le16 num;
-               __le16 count;
-       } __packed req;
-
-       __le32 data[SCARLETT2_MUX_MAX];
-
-       private->mux_updated = 0;
-
-       req.num = 0;
-       req.count = cpu_to_le16(count);
-
-       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_MUX,
-                           &req, sizeof(req),
-                           data, count * sizeof(u32));
-       if (err < 0)
-               return err;
-
-       for (i = 0; i < count; i++)
-               scarlett2_usb_populate_mux(private, le32_to_cpu(data[i]));
-
-       return 0;
-}
-
-/* Send USB messages to set mux inputs */
-static int scarlett2_usb_set_mux(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int table;
-
-       struct {
-               __le16 pad;
-               __le16 num;
-               __le32 data[SCARLETT2_MUX_MAX];
-       } __packed req;
-
-       req.pad = 0;
-
-       /* set mux settings for each rate */
-       for (table = 0; table < SCARLETT2_MUX_TABLES; table++) {
-               const struct scarlett2_mux_entry *entry;
-
-               /* i counts over the output array */
-               int i = 0, err;
-
-               req.num = cpu_to_le16(table);
-
-               /* loop through each entry */
-               for (entry = info->mux_assignment[table];
-                    entry->count;
-                    entry++) {
-                       int j;
-                       int port_type = entry->port_type;
-                       int port_idx = entry->start;
-                       int mux_idx = scarlett2_get_port_start_num(port_count,
-                               SCARLETT2_PORT_OUT, port_type) + port_idx;
-                       int dst_id = scarlett2_ports[port_type].id + port_idx;
-
-                       /* Empty slots */
-                       if (!dst_id) {
-                               for (j = 0; j < entry->count; j++)
-                                       req.data[i++] = 0;
-                               continue;
-                       }
-
-                       /* Non-empty mux slots use the lower 12 bits
-                        * for the destination and next 12 bits for
-                        * the source
-                        */
-                       for (j = 0; j < entry->count; j++) {
-                               int src_id = scarlett2_mux_src_num_to_id(
-                                       port_count, private->mux[mux_idx++]);
-                               req.data[i++] = cpu_to_le32(dst_id |
-                                                           src_id << 12);
-                               dst_id++;
-                       }
-               }
-
-               err = scarlett2_usb(mixer, SCARLETT2_USB_SET_MUX,
-                                   &req, (i + 1) * sizeof(u32),
-                                   NULL, 0);
-               if (err < 0)
-                       return err;
-       }
-
-       return 0;
-}
-
-/* Send USB message to get meter levels */
-static int scarlett2_usb_get_meter_levels(struct usb_mixer_interface *mixer,
-                                         u16 num_meters, u16 *levels)
-{
-       struct {
-               __le16 pad;
-               __le16 num_meters;
-               __le32 magic;
-       } __packed req;
-       u32 resp[SCARLETT2_MAX_METERS];
-       int i, err;
-
-       req.pad = 0;
-       req.num_meters = cpu_to_le16(num_meters);
-       req.magic = cpu_to_le32(SCARLETT2_USB_METER_LEVELS_GET_MAGIC);
-       err = scarlett2_usb(mixer, SCARLETT2_USB_GET_METER,
-                           &req, sizeof(req), resp, num_meters * sizeof(u32));
-       if (err < 0)
-               return err;
-
-       /* copy, convert to u16 */
-       for (i = 0; i < num_meters; i++)
-               levels[i] = resp[i];
-
-       return 0;
-}
-
-/*** Control Functions ***/
-
-/* helper function to create a new control */
-static int scarlett2_add_new_ctl(struct usb_mixer_interface *mixer,
-                                const struct snd_kcontrol_new *ncontrol,
-                                int index, int channels, const char *name,
-                                struct snd_kcontrol **kctl_return)
-{
-       struct snd_kcontrol *kctl;
-       struct usb_mixer_elem_info *elem;
-       int err;
-
-       elem = kzalloc(sizeof(*elem), GFP_KERNEL);
-       if (!elem)
-               return -ENOMEM;
-
-       /* We set USB_MIXER_BESPOKEN type, so that the core USB mixer code
-        * ignores them for resume and other operations.
-        * Also, the head.id field is set to 0, as we don't use this field.
-        */
-       elem->head.mixer = mixer;
-       elem->control = index;
-       elem->head.id = 0;
-       elem->channels = channels;
-       elem->val_type = USB_MIXER_BESPOKEN;
-
-       kctl = snd_ctl_new1(ncontrol, elem);
-       if (!kctl) {
-               kfree(elem);
-               return -ENOMEM;
-       }
-       kctl->private_free = snd_usb_mixer_elem_free;
-
-       strscpy(kctl->id.name, name, sizeof(kctl->id.name));
-
-       err = snd_usb_mixer_add_control(&elem->head, kctl);
-       if (err < 0)
-               return err;
-
-       if (kctl_return)
-               *kctl_return = kctl;
-
-       return 0;
-}
-
-/*** Sync Control ***/
-
-/* Update sync control after receiving notification that the status
- * has changed
- */
-static int scarlett2_update_sync(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       private->sync_updated = 0;
-       return scarlett2_usb_get_sync_status(mixer, &private->sync);
-}
-
-static int scarlett2_sync_ctl_info(struct snd_kcontrol *kctl,
-                                  struct snd_ctl_elem_info *uinfo)
-{
-       static const char *texts[2] = {
-               "Unlocked", "Locked"
-       };
-       return snd_ctl_enum_info(uinfo, 1, 2, texts);
-}
-
-static int scarlett2_sync_ctl_get(struct snd_kcontrol *kctl,
-                                 struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->sync_updated)
-               scarlett2_update_sync(mixer);
-       ucontrol->value.enumerated.item[0] = private->sync;
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static const struct snd_kcontrol_new scarlett2_sync_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .access = SNDRV_CTL_ELEM_ACCESS_READ,
-       .name = "",
-       .info = scarlett2_sync_ctl_info,
-       .get  = scarlett2_sync_ctl_get
-};
-
-static int scarlett2_add_sync_ctl(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       /* devices without a mixer also don't support reporting sync status */
-       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
-               return 0;
-
-       return scarlett2_add_new_ctl(mixer, &scarlett2_sync_ctl,
-                                    0, 1, "Sync Status", &private->sync_ctl);
-}
-
-/*** Analogue Line Out Volume Controls ***/
-
-/* Update hardware volume controls after receiving notification that
- * they have changed
- */
-static int scarlett2_update_volumes(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       struct scarlett2_usb_volume_status volume_status;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int err, i;
-       int mute;
-
-       private->vol_updated = 0;
-
-       err = scarlett2_usb_get_volume_status(mixer, &volume_status);
-       if (err < 0)
-               return err;
-
-       private->master_vol = clamp(
-               volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
-               0, SCARLETT2_VOLUME_BIAS);
-
-       if (info->line_out_hw_vol)
-               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
-                       private->dim_mute[i] = !!volume_status.dim_mute[i];
-
-       mute = private->dim_mute[SCARLETT2_BUTTON_MUTE];
-
-       for (i = 0; i < num_line_out; i++)
-               if (private->vol_sw_hw_switch[i]) {
-                       private->vol[i] = private->master_vol;
-                       private->mute_switch[i] = mute;
-               }
-
-       return 0;
-}
-
-static int scarlett2_volume_ctl_info(struct snd_kcontrol *kctl,
-                                    struct snd_ctl_elem_info *uinfo)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-
-       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
-       uinfo->count = elem->channels;
-       uinfo->value.integer.min = 0;
-       uinfo->value.integer.max = SCARLETT2_VOLUME_BIAS;
-       uinfo->value.integer.step = 1;
-       return 0;
-}
-
-static int scarlett2_master_volume_ctl_get(struct snd_kcontrol *kctl,
-                                          struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->vol_updated)
-               scarlett2_update_volumes(mixer);
-       mutex_unlock(&private->data_mutex);
-
-       ucontrol->value.integer.value[0] = private->master_vol;
-       return 0;
-}
-
-static int line_out_remap(struct scarlett2_data *private, int index)
-{
-       const struct scarlett2_device_info *info = private->info;
-
-       if (!info->line_out_remap_enable)
-               return index;
-       return info->line_out_remap[index];
-}
-
-static int scarlett2_volume_ctl_get(struct snd_kcontrol *kctl,
-                                   struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int index = line_out_remap(private, elem->control);
-
-       mutex_lock(&private->data_mutex);
-       if (private->vol_updated)
-               scarlett2_update_volumes(mixer);
-       mutex_unlock(&private->data_mutex);
-
-       ucontrol->value.integer.value[0] = private->vol[index];
-       return 0;
-}
-
-static int scarlett2_volume_ctl_put(struct snd_kcontrol *kctl,
-                                   struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int index = line_out_remap(private, elem->control);
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->vol[index];
-       val = ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->vol[index] = val;
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
-                                      index, val - SCARLETT2_VOLUME_BIAS);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const DECLARE_TLV_DB_MINMAX(
-       db_scale_scarlett2_gain, -SCARLETT2_VOLUME_BIAS * 100, 0
-);
-
-static const struct snd_kcontrol_new scarlett2_master_volume_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .access = SNDRV_CTL_ELEM_ACCESS_READ |
-                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
-       .name = "",
-       .info = scarlett2_volume_ctl_info,
-       .get  = scarlett2_master_volume_ctl_get,
-       .private_value = 0, /* max value */
-       .tlv = { .p = db_scale_scarlett2_gain }
-};
-
-static const struct snd_kcontrol_new scarlett2_line_out_volume_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
-                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
-       .name = "",
-       .info = scarlett2_volume_ctl_info,
-       .get  = scarlett2_volume_ctl_get,
-       .put  = scarlett2_volume_ctl_put,
-       .private_value = 0, /* max value */
-       .tlv = { .p = db_scale_scarlett2_gain }
-};
-
-/*** Mute Switch Controls ***/
-
-static int scarlett2_mute_ctl_get(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int index = line_out_remap(private, elem->control);
-
-       mutex_lock(&private->data_mutex);
-       if (private->vol_updated)
-               scarlett2_update_volumes(mixer);
-       mutex_unlock(&private->data_mutex);
-
-       ucontrol->value.integer.value[0] = private->mute_switch[index];
-       return 0;
-}
-
-static int scarlett2_mute_ctl_put(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int index = line_out_remap(private, elem->control);
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->mute_switch[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->mute_switch[index] = val;
-
-       /* Send mute change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_mute_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_mute_ctl_get,
-       .put  = scarlett2_mute_ctl_put,
-};
-
-/*** HW/SW Volume Switch Controls ***/
-
-static void scarlett2_sw_hw_ctl_ro(struct scarlett2_data *private, int index)
-{
-       private->sw_hw_ctls[index]->vd[0].access &=
-               ~SNDRV_CTL_ELEM_ACCESS_WRITE;
-}
-
-static void scarlett2_sw_hw_ctl_rw(struct scarlett2_data *private, int index)
-{
-       private->sw_hw_ctls[index]->vd[0].access |=
-               SNDRV_CTL_ELEM_ACCESS_WRITE;
-}
-
-static int scarlett2_sw_hw_enum_ctl_info(struct snd_kcontrol *kctl,
-                                        struct snd_ctl_elem_info *uinfo)
-{
-       static const char *const values[2] = {
-               "SW", "HW"
-       };
-
-       return snd_ctl_enum_info(uinfo, 1, 2, values);
-}
-
-static int scarlett2_sw_hw_enum_ctl_get(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-       int index = line_out_remap(private, elem->control);
-
-       ucontrol->value.enumerated.item[0] = private->vol_sw_hw_switch[index];
-       return 0;
-}
-
-static void scarlett2_vol_ctl_set_writable(struct usb_mixer_interface *mixer,
-                                          int index, int value)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       struct snd_card *card = mixer->chip->card;
-
-       /* Set/Clear write bits */
-       if (value) {
-               private->vol_ctls[index]->vd[0].access |=
-                       SNDRV_CTL_ELEM_ACCESS_WRITE;
-               private->mute_ctls[index]->vd[0].access |=
-                       SNDRV_CTL_ELEM_ACCESS_WRITE;
-       } else {
-               private->vol_ctls[index]->vd[0].access &=
-                       ~SNDRV_CTL_ELEM_ACCESS_WRITE;
-               private->mute_ctls[index]->vd[0].access &=
-                       ~SNDRV_CTL_ELEM_ACCESS_WRITE;
-       }
-
-       /* Notify of write bit and possible value change */
-       snd_ctl_notify(card,
-                      SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
-                      &private->vol_ctls[index]->id);
-       snd_ctl_notify(card,
-                      SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
-                      &private->mute_ctls[index]->id);
-}
-
-static int scarlett2_sw_hw_change(struct usb_mixer_interface *mixer,
-                                 int ctl_index, int val)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       int index = line_out_remap(private, ctl_index);
-       int err;
-
-       private->vol_sw_hw_switch[index] = val;
-
-       /* Change access mode to RO (hardware controlled volume)
-        * or RW (software controlled volume)
-        */
-       scarlett2_vol_ctl_set_writable(mixer, ctl_index, !val);
-
-       /* Reset volume/mute to master volume/mute */
-       private->vol[index] = private->master_vol;
-       private->mute_switch[index] = private->dim_mute[SCARLETT2_BUTTON_MUTE];
-
-       /* Set SW volume to current HW volume */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
-               index, private->master_vol - SCARLETT2_VOLUME_BIAS);
-       if (err < 0)
-               return err;
-
-       /* Set SW mute to current HW mute */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
-               index, private->dim_mute[SCARLETT2_BUTTON_MUTE]);
-       if (err < 0)
-               return err;
-
-       /* Send SW/HW switch change to the device */
-       return scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_SW_HW_SWITCH,
-                                       index, val);
-}
-
-static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int ctl_index = elem->control;
-       int index = line_out_remap(private, ctl_index);
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->vol_sw_hw_switch[index];
-       val = !!ucontrol->value.enumerated.item[0];
-
-       if (oval == val)
-               goto unlock;
-
-       err = scarlett2_sw_hw_change(mixer, ctl_index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_sw_hw_enum_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = scarlett2_sw_hw_enum_ctl_info,
-       .get  = scarlett2_sw_hw_enum_ctl_get,
-       .put  = scarlett2_sw_hw_enum_ctl_put,
-};
-
-/*** Line Level/Instrument Level Switch Controls ***/
-
-static int scarlett2_update_input_other(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       private->input_other_updated = 0;
-
-       if (info->level_input_count) {
-               int err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_LEVEL_SWITCH,
-                       info->level_input_count + info->level_input_first,
-                       private->level_switch);
-               if (err < 0)
-                       return err;
-       }
-
-       if (info->pad_input_count) {
-               int err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_PAD_SWITCH,
-                       info->pad_input_count, private->pad_switch);
-               if (err < 0)
-                       return err;
-       }
-
-       if (info->air_input_count) {
-               int err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_AIR_SWITCH,
-                       info->air_input_count, private->air_switch);
-               if (err < 0)
-                       return err;
-       }
-
-       if (info->phantom_count) {
-               int err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_PHANTOM_SWITCH,
-                       info->phantom_count, private->phantom_switch);
-               if (err < 0)
-                       return err;
-
-               err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_PHANTOM_PERSISTENCE,
-                       1, &private->phantom_persistence);
-               if (err < 0)
-                       return err;
-       }
-
-       return 0;
-}
-
-static int scarlett2_level_enum_ctl_info(struct snd_kcontrol *kctl,
-                                        struct snd_ctl_elem_info *uinfo)
-{
-       static const char *const values[2] = {
-               "Line", "Inst"
-       };
-
-       return snd_ctl_enum_info(uinfo, 1, 2, values);
-}
-
-static int scarlett2_level_enum_ctl_get(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       int index = elem->control + info->level_input_first;
-
-       mutex_lock(&private->data_mutex);
-       if (private->input_other_updated)
-               scarlett2_update_input_other(mixer);
-       ucontrol->value.enumerated.item[0] = private->level_switch[index];
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_level_enum_ctl_put(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       int index = elem->control + info->level_input_first;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->level_switch[index];
-       val = !!ucontrol->value.enumerated.item[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->level_switch[index] = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_LEVEL_SWITCH,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_level_enum_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = scarlett2_level_enum_ctl_info,
-       .get  = scarlett2_level_enum_ctl_get,
-       .put  = scarlett2_level_enum_ctl_put,
-};
-
-/*** Pad Switch Controls ***/
-
-static int scarlett2_pad_ctl_get(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->input_other_updated)
-               scarlett2_update_input_other(mixer);
-       ucontrol->value.integer.value[0] =
-               private->pad_switch[elem->control];
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_pad_ctl_put(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->pad_switch[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->pad_switch[index] = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_PAD_SWITCH,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_pad_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_pad_ctl_get,
-       .put  = scarlett2_pad_ctl_put,
-};
-
-/*** Air Switch Controls ***/
-
-static int scarlett2_air_ctl_get(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->input_other_updated)
-               scarlett2_update_input_other(mixer);
-       ucontrol->value.integer.value[0] = private->air_switch[elem->control];
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_air_ctl_put(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->air_switch[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->air_switch[index] = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_AIR_SWITCH,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_air_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_air_ctl_get,
-       .put  = scarlett2_air_ctl_put,
-};
-
-/*** Phantom Switch Controls ***/
-
-static int scarlett2_phantom_ctl_get(struct snd_kcontrol *kctl,
-                                    struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->input_other_updated)
-               scarlett2_update_input_other(mixer);
-       ucontrol->value.integer.value[0] =
-               private->phantom_switch[elem->control];
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_phantom_ctl_put(struct snd_kcontrol *kctl,
-                                    struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->phantom_switch[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->phantom_switch[index] = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_PHANTOM_SWITCH,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_phantom_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_phantom_ctl_get,
-       .put  = scarlett2_phantom_ctl_put,
-};
-
-/*** Phantom Persistence Control ***/
-
-static int scarlett2_phantom_persistence_ctl_get(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-
-       ucontrol->value.integer.value[0] = private->phantom_persistence;
-       return 0;
-}
-
-static int scarlett2_phantom_persistence_ctl_put(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->phantom_persistence;
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->phantom_persistence = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_PHANTOM_PERSISTENCE, index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_phantom_persistence_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_phantom_persistence_ctl_get,
-       .put  = scarlett2_phantom_persistence_ctl_put,
-};
-
-/*** Direct Monitor Control ***/
-
-static int scarlett2_update_monitor_other(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       int err;
-
-       /* monitor_other_enable[0] enables speaker switching
-        * monitor_other_enable[1] enables talkback
-        */
-       u8 monitor_other_enable[2];
-
-       /* monitor_other_switch[0] activates the alternate speakers
-        * monitor_other_switch[1] activates talkback
-        */
-       u8 monitor_other_switch[2];
-
-       private->monitor_other_updated = 0;
-
-       if (info->direct_monitor)
-               return scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_DIRECT_MONITOR,
-                       1, &private->direct_monitor_switch);
-
-       /* if it doesn't do speaker switching then it also doesn't do
-        * talkback
-        */
-       if (!info->has_speaker_switching)
-               return 0;
-
-       err = scarlett2_usb_get_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
-               2, monitor_other_enable);
-       if (err < 0)
-               return err;
-
-       err = scarlett2_usb_get_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
-               2, monitor_other_switch);
-       if (err < 0)
-               return err;
-
-       if (!monitor_other_enable[0])
-               private->speaker_switching_switch = 0;
-       else
-               private->speaker_switching_switch = monitor_other_switch[0] + 1;
-
-       if (info->has_talkback) {
-               const int (*port_count)[SCARLETT2_PORT_DIRNS] =
-                       info->port_count;
-               int num_mixes =
-                       port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
-               u16 bitmap;
-               int i;
-
-               if (!monitor_other_enable[1])
-                       private->talkback_switch = 0;
-               else
-                       private->talkback_switch = monitor_other_switch[1] + 1;
-
-               err = scarlett2_usb_get_config(mixer,
-                                              SCARLETT2_CONFIG_TALKBACK_MAP,
-                                              1, &bitmap);
-               if (err < 0)
-                       return err;
-               for (i = 0; i < num_mixes; i++, bitmap >>= 1)
-                       private->talkback_map[i] = bitmap & 1;
-       }
-
-       return 0;
-}
-
-static int scarlett2_direct_monitor_ctl_get(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->monitor_other_updated)
-               scarlett2_update_monitor_other(mixer);
-       ucontrol->value.enumerated.item[0] = private->direct_monitor_switch;
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_direct_monitor_ctl_put(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->direct_monitor_switch;
-       val = min(ucontrol->value.enumerated.item[0], 2U);
-
-       if (oval == val)
-               goto unlock;
-
-       private->direct_monitor_switch = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_DIRECT_MONITOR, index, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static int scarlett2_direct_monitor_stereo_enum_ctl_info(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
-{
-       static const char *const values[3] = {
-               "Off", "Mono", "Stereo"
-       };
-
-       return snd_ctl_enum_info(uinfo, 1, 3, values);
-}
-
-/* Direct Monitor for Solo is mono-only and only needs a boolean control
- * Direct Monitor for 2i2 is selectable between Off/Mono/Stereo
- */
-static const struct snd_kcontrol_new scarlett2_direct_monitor_ctl[2] = {
-       {
-               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-               .name = "",
-               .info = snd_ctl_boolean_mono_info,
-               .get  = scarlett2_direct_monitor_ctl_get,
-               .put  = scarlett2_direct_monitor_ctl_put,
-       },
-       {
-               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-               .name = "",
-               .info = scarlett2_direct_monitor_stereo_enum_ctl_info,
-               .get  = scarlett2_direct_monitor_ctl_get,
-               .put  = scarlett2_direct_monitor_ctl_put,
-       }
-};
-
-static int scarlett2_add_direct_monitor_ctl(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const char *s;
-
-       if (!info->direct_monitor)
-               return 0;
-
-       s = info->direct_monitor == 1
-             ? "Direct Monitor Playback Switch"
-             : "Direct Monitor Playback Enum";
-
-       return scarlett2_add_new_ctl(
-               mixer, &scarlett2_direct_monitor_ctl[info->direct_monitor - 1],
-               0, 1, s, &private->direct_monitor_ctl);
-}
-
-/*** Speaker Switching Control ***/
-
-static int scarlett2_speaker_switch_enum_ctl_info(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
-{
-       static const char *const values[3] = {
-               "Off", "Main", "Alt"
-       };
-
-       return snd_ctl_enum_info(uinfo, 1, 3, values);
-}
-
-static int scarlett2_speaker_switch_enum_ctl_get(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->monitor_other_updated)
-               scarlett2_update_monitor_other(mixer);
-       ucontrol->value.enumerated.item[0] = private->speaker_switching_switch;
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-/* when speaker switching gets enabled, switch the main/alt speakers
- * to HW volume and disable those controls
- */
-static int scarlett2_speaker_switch_enable(struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       int i, err;
-
-       for (i = 0; i < 4; i++) {
-               int index = line_out_remap(private, i);
-
-               /* switch the main/alt speakers to HW volume */
-               if (!private->vol_sw_hw_switch[index]) {
-                       err = scarlett2_sw_hw_change(private->mixer, i, 1);
-                       if (err < 0)
-                               return err;
-               }
-
-               /* disable the line out SW/HW switch */
-               scarlett2_sw_hw_ctl_ro(private, i);
-               snd_ctl_notify(card,
-                              SNDRV_CTL_EVENT_MASK_VALUE |
-                                SNDRV_CTL_EVENT_MASK_INFO,
-                              &private->sw_hw_ctls[i]->id);
-       }
-
-       /* when the next monitor-other notify comes in, update the mux
-        * configuration
-        */
-       private->speaker_switching_switched = 1;
-
-       return 0;
-}
-
-/* when speaker switching gets disabled, reenable the hw/sw controls
- * and invalidate the routing
- */
-static void scarlett2_speaker_switch_disable(struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       int i;
-
-       /* enable the line out SW/HW switch */
-       for (i = 0; i < 4; i++) {
-               scarlett2_sw_hw_ctl_rw(private, i);
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
-                              &private->sw_hw_ctls[i]->id);
-       }
-
-       /* when the next monitor-other notify comes in, update the mux
-        * configuration
-        */
-       private->speaker_switching_switched = 1;
-}
-
-static int scarlett2_speaker_switch_enum_ctl_put(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->speaker_switching_switch;
-       val = min(ucontrol->value.enumerated.item[0], 2U);
-
-       if (oval == val)
-               goto unlock;
-
-       private->speaker_switching_switch = val;
-
-       /* enable/disable speaker switching */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
-               0, !!val);
-       if (err < 0)
-               goto unlock;
-
-       /* if speaker switching is enabled, select main or alt */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
-               0, val == 2);
-       if (err < 0)
-               goto unlock;
-
-       /* update controls if speaker switching gets enabled or disabled */
-       if (!oval && val)
-               err = scarlett2_speaker_switch_enable(mixer);
-       else if (oval && !val)
-               scarlett2_speaker_switch_disable(mixer);
-
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_speaker_switch_enum_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = scarlett2_speaker_switch_enum_ctl_info,
-       .get  = scarlett2_speaker_switch_enum_ctl_get,
-       .put  = scarlett2_speaker_switch_enum_ctl_put,
-};
-
-static int scarlett2_add_speaker_switch_ctl(
-       struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       if (!info->has_speaker_switching)
-               return 0;
-
-       return scarlett2_add_new_ctl(
-               mixer, &scarlett2_speaker_switch_enum_ctl,
-               0, 1, "Speaker Switching Playback Enum",
-               &private->speaker_switching_ctl);
-}
-
-/*** Talkback and Talkback Map Controls ***/
-
-static int scarlett2_talkback_enum_ctl_info(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
-{
-       static const char *const values[3] = {
-               "Disabled", "Off", "On"
-       };
-
-       return snd_ctl_enum_info(uinfo, 1, 3, values);
-}
-
-static int scarlett2_talkback_enum_ctl_get(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->monitor_other_updated)
-               scarlett2_update_monitor_other(mixer);
-       ucontrol->value.enumerated.item[0] = private->talkback_switch;
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_talkback_enum_ctl_put(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->talkback_switch;
-       val = min(ucontrol->value.enumerated.item[0], 2U);
-
-       if (oval == val)
-               goto unlock;
-
-       private->talkback_switch = val;
-
-       /* enable/disable talkback */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_ENABLE,
-               1, !!val);
-       if (err < 0)
-               goto unlock;
-
-       /* if talkback is enabled, select main or alt */
-       err = scarlett2_usb_set_config(
-               mixer, SCARLETT2_CONFIG_MONITOR_OTHER_SWITCH,
-               1, val == 2);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_talkback_enum_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = scarlett2_talkback_enum_ctl_info,
-       .get  = scarlett2_talkback_enum_ctl_get,
-       .put  = scarlett2_talkback_enum_ctl_put,
-};
-
-static int scarlett2_talkback_map_ctl_get(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       int index = elem->control;
-
-       ucontrol->value.integer.value[0] = private->talkback_map[index];
-
-       return 0;
-}
-
-static int scarlett2_talkback_map_ctl_put(
-       struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] =
-               private->info->port_count;
-       int num_mixes = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
-
-       int index = elem->control;
-       int oval, val, err = 0, i;
-       u16 bitmap = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->talkback_map[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->talkback_map[index] = val;
-
-       for (i = 0; i < num_mixes; i++)
-               bitmap |= private->talkback_map[i] << i;
-
-       /* Send updated bitmap to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_TALKBACK_MAP,
-                                      0, bitmap);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_talkback_map_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_talkback_map_ctl_get,
-       .put  = scarlett2_talkback_map_ctl_put,
-};
-
-static int scarlett2_add_talkback_ctls(
-       struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_mixes = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
-       int err, i;
-       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-
-       if (!info->has_talkback)
-               return 0;
-
-       err = scarlett2_add_new_ctl(
-               mixer, &scarlett2_talkback_enum_ctl,
-               0, 1, "Talkback Playback Enum",
-               &private->talkback_ctl);
-       if (err < 0)
-               return err;
-
-       for (i = 0; i < num_mixes; i++) {
-               snprintf(s, sizeof(s),
-                        "Talkback Mix %c Playback Switch", i + 'A');
-               err = scarlett2_add_new_ctl(mixer, &scarlett2_talkback_map_ctl,
-                                           i, 1, s, NULL);
-               if (err < 0)
-                       return err;
-       }
-
-       return 0;
-}
-
-/*** Dim/Mute Controls ***/
-
-static int scarlett2_dim_mute_ctl_get(struct snd_kcontrol *kctl,
-                                     struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       mutex_lock(&private->data_mutex);
-       if (private->vol_updated)
-               scarlett2_update_volumes(mixer);
-       mutex_unlock(&private->data_mutex);
-
-       ucontrol->value.integer.value[0] = private->dim_mute[elem->control];
-       return 0;
-}
-
-static int scarlett2_dim_mute_ctl_put(struct snd_kcontrol *kctl,
-                                     struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-
-       int index = elem->control;
-       int oval, val, err = 0, i;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->dim_mute[index];
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->dim_mute[index] = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_DIM_MUTE,
-                                      index, val);
-       if (err == 0)
-               err = 1;
-
-       if (index == SCARLETT2_BUTTON_MUTE)
-               for (i = 0; i < num_line_out; i++) {
-                       int line_index = line_out_remap(private, i);
-
-                       if (private->vol_sw_hw_switch[line_index]) {
-                               private->mute_switch[line_index] = val;
-                               snd_ctl_notify(mixer->chip->card,
-                                              SNDRV_CTL_EVENT_MASK_VALUE,
-                                              &private->mute_ctls[i]->id);
-                       }
-               }
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_dim_mute_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_dim_mute_ctl_get,
-       .put  = scarlett2_dim_mute_ctl_put
-};
-
-/*** Create the analogue output controls ***/
-
-static int scarlett2_add_line_out_ctls(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int err, i;
-       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-
-       /* Add R/O HW volume control */
-       if (info->line_out_hw_vol) {
-               snprintf(s, sizeof(s), "Master HW Playback Volume");
-               err = scarlett2_add_new_ctl(mixer,
-                                           &scarlett2_master_volume_ctl,
-                                           0, 1, s, &private->master_vol_ctl);
-               if (err < 0)
-                       return err;
-       }
-
-       /* Add volume controls */
-       for (i = 0; i < num_line_out; i++) {
-               int index = line_out_remap(private, i);
-
-               /* Fader */
-               if (info->line_out_descrs[i])
-                       snprintf(s, sizeof(s),
-                                "Line %02d (%s) Playback Volume",
-                                i + 1, info->line_out_descrs[i]);
-               else
-                       snprintf(s, sizeof(s),
-                                "Line %02d Playback Volume",
-                                i + 1);
-               err = scarlett2_add_new_ctl(mixer,
-                                           &scarlett2_line_out_volume_ctl,
-                                           i, 1, s, &private->vol_ctls[i]);
-               if (err < 0)
-                       return err;
-
-               /* Mute Switch */
-               snprintf(s, sizeof(s),
-                        "Line %02d Mute Playback Switch",
-                        i + 1);
-               err = scarlett2_add_new_ctl(mixer,
-                                           &scarlett2_mute_ctl,
-                                           i, 1, s,
-                                           &private->mute_ctls[i]);
-               if (err < 0)
-                       return err;
-
-               /* Make the fader and mute controls read-only if the
-                * SW/HW switch is set to HW
-                */
-               if (private->vol_sw_hw_switch[index])
-                       scarlett2_vol_ctl_set_writable(mixer, i, 0);
-
-               /* SW/HW Switch */
-               if (info->line_out_hw_vol) {
-                       snprintf(s, sizeof(s),
-                                "Line Out %02d Volume Control Playback Enum",
-                                i + 1);
-                       err = scarlett2_add_new_ctl(mixer,
-                                                   &scarlett2_sw_hw_enum_ctl,
-                                                   i, 1, s,
-                                                   &private->sw_hw_ctls[i]);
-                       if (err < 0)
-                               return err;
-
-                       /* Make the switch read-only if the line is
-                        * involved in speaker switching
-                        */
-                       if (private->speaker_switching_switch && i < 4)
-                               scarlett2_sw_hw_ctl_ro(private, i);
-               }
-       }
-
-       /* Add dim/mute controls */
-       if (info->line_out_hw_vol)
-               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++) {
-                       err = scarlett2_add_new_ctl(
-                               mixer, &scarlett2_dim_mute_ctl,
-                               i, 1, scarlett2_dim_mute_names[i],
-                               &private->dim_mute_ctls[i]);
-                       if (err < 0)
-                               return err;
-               }
-
-       return 0;
-}
-
-/*** Create the analogue input controls ***/
-
-static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       int err, i;
-       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-       const char *fmt = "Line In %d %s Capture %s";
-       const char *fmt2 = "Line In %d-%d %s Capture %s";
-
-       /* Add input level (line/inst) controls */
-       for (i = 0; i < info->level_input_count; i++) {
-               snprintf(s, sizeof(s), fmt, i + 1 + info->level_input_first,
-                        "Level", "Enum");
-               err = scarlett2_add_new_ctl(mixer, &scarlett2_level_enum_ctl,
-                                           i, 1, s, &private->level_ctls[i]);
-               if (err < 0)
-                       return err;
-       }
-
-       /* Add input pad controls */
-       for (i = 0; i < info->pad_input_count; i++) {
-               snprintf(s, sizeof(s), fmt, i + 1, "Pad", "Switch");
-               err = scarlett2_add_new_ctl(mixer, &scarlett2_pad_ctl,
-                                           i, 1, s, &private->pad_ctls[i]);
-               if (err < 0)
-                       return err;
-       }
-
-       /* Add input air controls */
-       for (i = 0; i < info->air_input_count; i++) {
-               snprintf(s, sizeof(s), fmt, i + 1, "Air", "Switch");
-               err = scarlett2_add_new_ctl(mixer, &scarlett2_air_ctl,
-                                           i, 1, s, &private->air_ctls[i]);
-               if (err < 0)
-                       return err;
-       }
-
-       /* Add input phantom controls */
-       if (info->inputs_per_phantom == 1) {
-               for (i = 0; i < info->phantom_count; i++) {
-                       scnprintf(s, sizeof(s), fmt, i + 1,
-                                 "Phantom Power", "Switch");
-                       err = scarlett2_add_new_ctl(
-                               mixer, &scarlett2_phantom_ctl,
-                               i, 1, s, &private->phantom_ctls[i]);
-                       if (err < 0)
-                               return err;
-               }
-       } else if (info->inputs_per_phantom > 1) {
-               for (i = 0; i < info->phantom_count; i++) {
-                       int from = i * info->inputs_per_phantom + 1;
-                       int to = (i + 1) * info->inputs_per_phantom;
-
-                       scnprintf(s, sizeof(s), fmt2, from, to,
-                                 "Phantom Power", "Switch");
-                       err = scarlett2_add_new_ctl(
-                               mixer, &scarlett2_phantom_ctl,
-                               i, 1, s, &private->phantom_ctls[i]);
-                       if (err < 0)
-                               return err;
-               }
-       }
-       if (info->phantom_count) {
-               err = scarlett2_add_new_ctl(
-                       mixer, &scarlett2_phantom_persistence_ctl, 0, 1,
-                       "Phantom Power Persistence Capture Switch", NULL);
-               if (err < 0)
-                       return err;
-       }
-
-       return 0;
-}
-
-/*** Mixer Volume Controls ***/
-
-static int scarlett2_mixer_ctl_info(struct snd_kcontrol *kctl,
-                                   struct snd_ctl_elem_info *uinfo)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-
-       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
-       uinfo->count = elem->channels;
-       uinfo->value.integer.min = 0;
-       uinfo->value.integer.max = SCARLETT2_MIXER_MAX_VALUE;
-       uinfo->value.integer.step = 1;
-       return 0;
-}
-
-static int scarlett2_mixer_ctl_get(struct snd_kcontrol *kctl,
-                                  struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-
-       ucontrol->value.integer.value[0] = private->mix[elem->control];
-       return 0;
-}
-
-static int scarlett2_mixer_ctl_put(struct snd_kcontrol *kctl,
-                                  struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int oval, val, num_mixer_in, mix_num, err = 0;
-       int index = elem->control;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->mix[index];
-       val = ucontrol->value.integer.value[0];
-       num_mixer_in = port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
-       mix_num = index / num_mixer_in;
-
-       if (oval == val)
-               goto unlock;
-
-       private->mix[index] = val;
-       err = scarlett2_usb_set_mix(mixer, mix_num);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const DECLARE_TLV_DB_MINMAX(
-       db_scale_scarlett2_mixer,
-       SCARLETT2_MIXER_MIN_DB * 100,
-       SCARLETT2_MIXER_MAX_DB * 100
-);
-
-static const struct snd_kcontrol_new scarlett2_mixer_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
-                 SNDRV_CTL_ELEM_ACCESS_TLV_READ,
-       .name = "",
-       .info = scarlett2_mixer_ctl_info,
-       .get  = scarlett2_mixer_ctl_get,
-       .put  = scarlett2_mixer_ctl_put,
-       .private_value = SCARLETT2_MIXER_MAX_DB, /* max value */
-       .tlv = { .p = db_scale_scarlett2_mixer }
-};
-
-static int scarlett2_add_mixer_ctls(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int err, i, j;
-       int index;
-       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-
-       int num_inputs =
-               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT];
-       int num_outputs =
-               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
-
-       for (i = 0, index = 0; i < num_outputs; i++)
-               for (j = 0; j < num_inputs; j++, index++) {
-                       snprintf(s, sizeof(s),
-                                "Mix %c Input %02d Playback Volume",
-                                'A' + i, j + 1);
-                       err = scarlett2_add_new_ctl(mixer, &scarlett2_mixer_ctl,
-                                                   index, 1, s, NULL);
-                       if (err < 0)
-                               return err;
-               }
-
-       return 0;
-}
-
-/*** Mux Source Selection Controls ***/
-
-static int scarlett2_mux_src_enum_ctl_info(struct snd_kcontrol *kctl,
-                                          struct snd_ctl_elem_info *uinfo)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       unsigned int item = uinfo->value.enumerated.item;
-       int items = private->num_mux_srcs;
-       int port_type;
-
-       uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
-       uinfo->count = elem->channels;
-       uinfo->value.enumerated.items = items;
-
-       if (item >= items)
-               item = uinfo->value.enumerated.item = items - 1;
-
-       for (port_type = 0;
-            port_type < SCARLETT2_PORT_TYPE_COUNT;
-            port_type++) {
-               if (item < port_count[port_type][SCARLETT2_PORT_IN]) {
-                       const struct scarlett2_port *port =
-                               &scarlett2_ports[port_type];
-
-                       sprintf(uinfo->value.enumerated.name,
-                               port->src_descr, item + port->src_num_offset);
-                       return 0;
-               }
-               item -= port_count[port_type][SCARLETT2_PORT_IN];
-       }
-
-       return -EINVAL;
-}
-
-static int scarlett2_mux_src_enum_ctl_get(struct snd_kcontrol *kctl,
-                                         struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int line_out_count =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int index = elem->control;
-
-       if (index < line_out_count)
-               index = line_out_remap(private, index);
-
-       mutex_lock(&private->data_mutex);
-       if (private->mux_updated)
-               scarlett2_usb_get_mux(mixer);
-       ucontrol->value.enumerated.item[0] = private->mux[index];
-       mutex_unlock(&private->data_mutex);
-
-       return 0;
-}
-
-static int scarlett2_mux_src_enum_ctl_put(struct snd_kcontrol *kctl,
-                                         struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int line_out_count =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int index = elem->control;
-       int oval, val, err = 0;
-
-       if (index < line_out_count)
-               index = line_out_remap(private, index);
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->mux[index];
-       val = min(ucontrol->value.enumerated.item[0],
-                 private->num_mux_srcs - 1U);
-
-       if (oval == val)
-               goto unlock;
-
-       private->mux[index] = val;
-       err = scarlett2_usb_set_mux(mixer);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_mux_src_enum_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = scarlett2_mux_src_enum_ctl_info,
-       .get  = scarlett2_mux_src_enum_ctl_get,
-       .put  = scarlett2_mux_src_enum_ctl_put,
-};
-
-static int scarlett2_add_mux_enums(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int port_type, channel, i;
-
-       for (i = 0, port_type = 0;
-            port_type < SCARLETT2_PORT_TYPE_COUNT;
-            port_type++) {
-               for (channel = 0;
-                    channel < port_count[port_type][SCARLETT2_PORT_OUT];
-                    channel++, i++) {
-                       int err;
-                       char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
-                       const char *const descr =
-                               scarlett2_ports[port_type].dst_descr;
-
-                       snprintf(s, sizeof(s) - 5, descr, channel + 1);
-                       strcat(s, " Enum");
-
-                       err = scarlett2_add_new_ctl(mixer,
-                                                   &scarlett2_mux_src_enum_ctl,
-                                                   i, 1, s,
-                                                   &private->mux_ctls[i]);
-                       if (err < 0)
-                               return err;
-               }
-       }
-
-       return 0;
-}
-
-/*** Meter Controls ***/
-
-static int scarlett2_meter_ctl_info(struct snd_kcontrol *kctl,
-                                   struct snd_ctl_elem_info *uinfo)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-
-       uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
-       uinfo->count = elem->channels;
-       uinfo->value.integer.min = 0;
-       uinfo->value.integer.max = 4095;
-       uinfo->value.integer.step = 1;
-       return 0;
-}
-
-static int scarlett2_meter_ctl_get(struct snd_kcontrol *kctl,
-                                  struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       u16 meter_levels[SCARLETT2_MAX_METERS];
-       int i, err;
-
-       err = scarlett2_usb_get_meter_levels(elem->head.mixer, elem->channels,
-                                            meter_levels);
-       if (err < 0)
-               return err;
-
-       for (i = 0; i < elem->channels; i++)
-               ucontrol->value.integer.value[i] = meter_levels[i];
-
-       return 0;
-}
-
-static const struct snd_kcontrol_new scarlett2_meter_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_PCM,
-       .access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
-       .name = "",
-       .info = scarlett2_meter_ctl_info,
-       .get  = scarlett2_meter_ctl_get
-};
-
-static int scarlett2_add_meter_ctl(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       /* devices without a mixer also don't support reporting levels */
-       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
-               return 0;
-
-       return scarlett2_add_new_ctl(mixer, &scarlett2_meter_ctl,
-                                    0, private->num_mux_dsts,
-                                    "Level Meter", NULL);
-}
-
-/*** MSD Controls ***/
-
-static int scarlett2_msd_ctl_get(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-
-       ucontrol->value.integer.value[0] = private->msd_switch;
-       return 0;
-}
-
-static int scarlett2_msd_ctl_put(struct snd_kcontrol *kctl,
-                                struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->msd_switch;
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->msd_switch = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MSD_SWITCH,
-                                      0, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_msd_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_msd_ctl_get,
-       .put  = scarlett2_msd_ctl_put,
-};
-
-static int scarlett2_add_msd_ctl(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       if (!info->has_msd_mode)
-               return 0;
-
-       /* If MSD mode is off, hide the switch by default */
-       if (!private->msd_switch && !(mixer->chip->setup & SCARLETT2_MSD_ENABLE))
-               return 0;
-
-       /* Add MSD control */
-       return scarlett2_add_new_ctl(mixer, &scarlett2_msd_ctl,
-                                    0, 1, "MSD Mode Switch", NULL);
-}
-
-/*** Standalone Control ***/
-
-static int scarlett2_standalone_ctl_get(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct scarlett2_data *private = elem->head.mixer->private_data;
-
-       ucontrol->value.integer.value[0] = private->standalone_switch;
-       return 0;
-}
-
-static int scarlett2_standalone_ctl_put(struct snd_kcontrol *kctl,
-                                       struct snd_ctl_elem_value *ucontrol)
-{
-       struct usb_mixer_elem_info *elem = kctl->private_data;
-       struct usb_mixer_interface *mixer = elem->head.mixer;
-       struct scarlett2_data *private = mixer->private_data;
-
-       int oval, val, err = 0;
-
-       mutex_lock(&private->data_mutex);
-
-       oval = private->standalone_switch;
-       val = !!ucontrol->value.integer.value[0];
-
-       if (oval == val)
-               goto unlock;
-
-       private->standalone_switch = val;
-
-       /* Send switch change to the device */
-       err = scarlett2_usb_set_config(mixer,
-                                      SCARLETT2_CONFIG_STANDALONE_SWITCH,
-                                      0, val);
-       if (err == 0)
-               err = 1;
-
-unlock:
-       mutex_unlock(&private->data_mutex);
-       return err;
-}
-
-static const struct snd_kcontrol_new scarlett2_standalone_ctl = {
-       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
-       .name = "",
-       .info = snd_ctl_boolean_mono_info,
-       .get  = scarlett2_standalone_ctl_get,
-       .put  = scarlett2_standalone_ctl_put,
-};
-
-static int scarlett2_add_standalone_ctl(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
-               return 0;
-
-       /* Add standalone control */
-       return scarlett2_add_new_ctl(mixer, &scarlett2_standalone_ctl,
-                                    0, 1, "Standalone Switch", NULL);
-}
-
-/*** Cleanup/Suspend Callbacks ***/
-
-static void scarlett2_private_free(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       cancel_delayed_work_sync(&private->work);
-       kfree(private);
-       mixer->private_data = NULL;
-}
-
-static void scarlett2_private_suspend(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       if (cancel_delayed_work_sync(&private->work))
-               scarlett2_config_save(private->mixer);
-}
-
-/*** Initialisation ***/
-
-static void scarlett2_count_mux_io(struct scarlett2_data *private)
-{
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int port_type, srcs = 0, dsts = 0;
-
-       for (port_type = 0;
-            port_type < SCARLETT2_PORT_TYPE_COUNT;
-            port_type++) {
-               srcs += port_count[port_type][SCARLETT2_PORT_IN];
-               dsts += port_count[port_type][SCARLETT2_PORT_OUT];
-       }
-
-       private->num_mux_srcs = srcs;
-       private->num_mux_dsts = dsts;
-}
-
-/* Look through the interface descriptors for the Focusrite Control
- * interface (bInterfaceClass = 255 Vendor Specific Class) and set
- * bInterfaceNumber, bEndpointAddress, wMaxPacketSize, and bInterval
- * in private
- */
-static int scarlett2_find_fc_interface(struct usb_device *dev,
-                                      struct scarlett2_data *private)
-{
-       struct usb_host_config *config = dev->actconfig;
-       int i;
-
-       for (i = 0; i < config->desc.bNumInterfaces; i++) {
-               struct usb_interface *intf = config->interface[i];
-               struct usb_interface_descriptor *desc =
-                       &intf->altsetting[0].desc;
-               struct usb_endpoint_descriptor *epd;
-
-               if (desc->bInterfaceClass != 255)
-                       continue;
-
-               epd = get_endpoint(intf->altsetting, 0);
-               private->bInterfaceNumber = desc->bInterfaceNumber;
-               private->bEndpointAddress = epd->bEndpointAddress &
-                       USB_ENDPOINT_NUMBER_MASK;
-               private->wMaxPacketSize = le16_to_cpu(epd->wMaxPacketSize);
-               private->bInterval = epd->bInterval;
-               return 0;
-       }
-
-       return -EINVAL;
-}
-
-/* Initialise private data */
-static int scarlett2_init_private(struct usb_mixer_interface *mixer,
-                                 const struct scarlett2_device_entry *entry)
-{
-       struct scarlett2_data *private =
-               kzalloc(sizeof(struct scarlett2_data), GFP_KERNEL);
-
-       if (!private)
-               return -ENOMEM;
-
-       mutex_init(&private->usb_mutex);
-       mutex_init(&private->data_mutex);
-       INIT_DELAYED_WORK(&private->work, scarlett2_config_save_work);
-
-       mixer->private_data = private;
-       mixer->private_free = scarlett2_private_free;
-       mixer->private_suspend = scarlett2_private_suspend;
-
-       private->info = entry->info;
-       private->series_name = entry->series_name;
-       scarlett2_count_mux_io(private);
-       private->scarlett2_seq = 0;
-       private->mixer = mixer;
-
-       return scarlett2_find_fc_interface(mixer->chip->dev, private);
-}
-
-/* Cargo cult proprietary initialisation sequence */
-static int scarlett2_usb_init(struct usb_mixer_interface *mixer)
-{
-       struct usb_device *dev = mixer->chip->dev;
-       struct scarlett2_data *private = mixer->private_data;
-       u8 buf[24];
-       int err;
-
-       if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
-               return -EINVAL;
-
-       /* step 0 */
-       err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
-                              SCARLETT2_USB_CMD_INIT, buf, sizeof(buf));
-       if (err < 0)
-               return err;
-
-       /* step 1 */
-       private->scarlett2_seq = 1;
-       err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_1, NULL, 0, NULL, 0);
-       if (err < 0)
-               return err;
-
-       /* step 2 */
-       private->scarlett2_seq = 1;
-       return scarlett2_usb(mixer, SCARLETT2_USB_INIT_2, NULL, 0, NULL, 84);
-}
-
-/* Read configuration from the interface on start */
-static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int num_mixer_out =
-               port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN];
-       struct scarlett2_usb_volume_status volume_status;
-       int err, i;
-
-       if (info->has_msd_mode) {
-               err = scarlett2_usb_get_config(
-                       mixer, SCARLETT2_CONFIG_MSD_SWITCH,
-                       1, &private->msd_switch);
-               if (err < 0)
-                       return err;
-
-               /* no other controls are created if MSD mode is on */
-               if (private->msd_switch)
-                       return 0;
-       }
-
-       err = scarlett2_update_input_other(mixer);
-       if (err < 0)
-               return err;
-
-       err = scarlett2_update_monitor_other(mixer);
-       if (err < 0)
-               return err;
-
-       /* the rest of the configuration is for devices with a mixer */
-       if (info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
-               return 0;
-
-       err = scarlett2_usb_get_config(
-               mixer, SCARLETT2_CONFIG_STANDALONE_SWITCH,
-               1, &private->standalone_switch);
-       if (err < 0)
-               return err;
-
-       err = scarlett2_update_sync(mixer);
-       if (err < 0)
-               return err;
-
-       err = scarlett2_usb_get_volume_status(mixer, &volume_status);
-       if (err < 0)
-               return err;
-
-       if (info->line_out_hw_vol)
-               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
-                       private->dim_mute[i] = !!volume_status.dim_mute[i];
-
-       private->master_vol = clamp(
-               volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
-               0, SCARLETT2_VOLUME_BIAS);
-
-       for (i = 0; i < num_line_out; i++) {
-               int volume, mute;
-
-               private->vol_sw_hw_switch[i] =
-                       info->line_out_hw_vol
-                               && volume_status.sw_hw_switch[i];
-
-               volume = private->vol_sw_hw_switch[i]
-                          ? volume_status.master_vol
-                          : volume_status.sw_vol[i];
-               volume = clamp(volume + SCARLETT2_VOLUME_BIAS,
-                              0, SCARLETT2_VOLUME_BIAS);
-               private->vol[i] = volume;
-
-               mute = private->vol_sw_hw_switch[i]
-                        ? private->dim_mute[SCARLETT2_BUTTON_MUTE]
-                        : volume_status.mute_switch[i];
-               private->mute_switch[i] = mute;
-       }
-
-       for (i = 0; i < num_mixer_out; i++) {
-               err = scarlett2_usb_get_mix(mixer, i);
-               if (err < 0)
-                       return err;
-       }
-
-       return scarlett2_usb_get_mux(mixer);
-}
-
-/* Notify on sync change */
-static void scarlett2_notify_sync(
-       struct usb_mixer_interface *mixer)
-{
-       struct scarlett2_data *private = mixer->private_data;
-
-       private->sync_updated = 1;
-
-       snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
-                      &private->sync_ctl->id);
-}
-
-/* Notify on monitor change */
-static void scarlett2_notify_monitor(
-       struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int i;
-
-       /* if line_out_hw_vol is 0, there are no controls to update */
-       if (!info->line_out_hw_vol)
-               return;
-
-       private->vol_updated = 1;
-
-       snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
-                      &private->master_vol_ctl->id);
-
-       for (i = 0; i < num_line_out; i++)
-               if (private->vol_sw_hw_switch[line_out_remap(private, i)])
-                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                                      &private->vol_ctls[i]->id);
-}
-
-/* Notify on dim/mute change */
-static void scarlett2_notify_dim_mute(
-       struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-       int num_line_out =
-               port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-       int i;
-
-       private->vol_updated = 1;
-
-       if (!info->line_out_hw_vol)
-               return;
-
-       for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->dim_mute_ctls[i]->id);
-
-       for (i = 0; i < num_line_out; i++)
-               if (private->vol_sw_hw_switch[line_out_remap(private, i)])
-                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                                      &private->mute_ctls[i]->id);
-}
-
-/* Notify on "input other" change (level/pad/air) */
-static void scarlett2_notify_input_other(
-       struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-       int i;
-
-       private->input_other_updated = 1;
-
-       for (i = 0; i < info->level_input_count; i++)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->level_ctls[i]->id);
-       for (i = 0; i < info->pad_input_count; i++)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->pad_ctls[i]->id);
-       for (i = 0; i < info->air_input_count; i++)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->air_ctls[i]->id);
-       for (i = 0; i < info->phantom_count; i++)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->phantom_ctls[i]->id);
-}
-
-/* Notify on "monitor other" change (direct monitor, speaker
- * switching, talkback)
- */
-static void scarlett2_notify_monitor_other(
-       struct usb_mixer_interface *mixer)
-{
-       struct snd_card *card = mixer->chip->card;
-       struct scarlett2_data *private = mixer->private_data;
-       const struct scarlett2_device_info *info = private->info;
-
-       private->monitor_other_updated = 1;
-
-       if (info->direct_monitor) {
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->direct_monitor_ctl->id);
-               return;
-       }
-
-       if (info->has_speaker_switching)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->speaker_switching_ctl->id);
-
-       if (info->has_talkback)
-               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                              &private->talkback_ctl->id);
-
-       /* if speaker switching was recently enabled or disabled,
-        * invalidate the dim/mute and mux enum controls
-        */
-       if (private->speaker_switching_switched) {
-               int i;
-
-               scarlett2_notify_dim_mute(mixer);
-
-               private->speaker_switching_switched = 0;
-               private->mux_updated = 1;
-
-               for (i = 0; i < private->num_mux_dsts; i++)
-                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
-                                      &private->mux_ctls[i]->id);
-       }
-}
-
-/* Interrupt callback */
-static void scarlett2_notify(struct urb *urb)
-{
-       struct usb_mixer_interface *mixer = urb->context;
-       int len = urb->actual_length;
-       int ustatus = urb->status;
-       u32 data;
-
-       if (ustatus != 0 || len != 8)
-               goto requeue;
-
-       data = le32_to_cpu(*(__le32 *)urb->transfer_buffer);
-       if (data & SCARLETT2_USB_NOTIFY_SYNC)
-               scarlett2_notify_sync(mixer);
-       if (data & SCARLETT2_USB_NOTIFY_MONITOR)
-               scarlett2_notify_monitor(mixer);
-       if (data & SCARLETT2_USB_NOTIFY_DIM_MUTE)
-               scarlett2_notify_dim_mute(mixer);
-       if (data & SCARLETT2_USB_NOTIFY_INPUT_OTHER)
-               scarlett2_notify_input_other(mixer);
-       if (data & SCARLETT2_USB_NOTIFY_MONITOR_OTHER)
-               scarlett2_notify_monitor_other(mixer);
-
-requeue:
-       if (ustatus != -ENOENT &&
-           ustatus != -ECONNRESET &&
-           ustatus != -ESHUTDOWN) {
-               urb->dev = mixer->chip->dev;
-               usb_submit_urb(urb, GFP_ATOMIC);
-       }
-}
-
-static int scarlett2_init_notify(struct usb_mixer_interface *mixer)
-{
-       struct usb_device *dev = mixer->chip->dev;
-       struct scarlett2_data *private = mixer->private_data;
-       unsigned int pipe = usb_rcvintpipe(dev, private->bEndpointAddress);
-       void *transfer_buffer;
-
-       if (mixer->urb) {
-               usb_audio_err(mixer->chip,
-                             "%s: mixer urb already in use!\n", __func__);
-               return 0;
-       }
-
-       if (usb_pipe_type_check(dev, pipe))
-               return -EINVAL;
-
-       mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
-       if (!mixer->urb)
-               return -ENOMEM;
-
-       transfer_buffer = kmalloc(private->wMaxPacketSize, GFP_KERNEL);
-       if (!transfer_buffer)
-               return -ENOMEM;
-
-       usb_fill_int_urb(mixer->urb, dev, pipe,
-                        transfer_buffer, private->wMaxPacketSize,
-                        scarlett2_notify, mixer, private->bInterval);
-
-       return usb_submit_urb(mixer->urb, GFP_KERNEL);
-}
-
-static const struct scarlett2_device_entry *get_scarlett2_device_entry(
-       struct usb_mixer_interface *mixer)
-{
-       const struct scarlett2_device_entry *entry = scarlett2_devices;
-
-       /* Find entry in scarlett2_devices */
-       while (entry->usb_id && entry->usb_id != mixer->chip->usb_id)
-               entry++;
-       if (!entry->usb_id)
-               return NULL;
-
-       return entry;
-}
-
-static int snd_scarlett_gen2_controls_create(
-       struct usb_mixer_interface *mixer,
-       const struct scarlett2_device_entry *entry)
-{
-       int err;
-
-       /* Initialise private data */
-       err = scarlett2_init_private(mixer, entry);
-       if (err < 0)
-               return err;
-
-       /* Send proprietary USB initialisation sequence */
-       err = scarlett2_usb_init(mixer);
-       if (err < 0)
-               return err;
-
-       /* Read volume levels and controls from the interface */
-       err = scarlett2_read_configs(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the MSD control */
-       err = scarlett2_add_msd_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* If MSD mode is enabled, don't create any other controls */
-       if (((struct scarlett2_data *)mixer->private_data)->msd_switch)
-               return 0;
-
-       /* Create the analogue output controls */
-       err = scarlett2_add_line_out_ctls(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the analogue input controls */
-       err = scarlett2_add_line_in_ctls(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the input, output, and mixer mux input selections */
-       err = scarlett2_add_mux_enums(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the matrix mixer controls */
-       err = scarlett2_add_mixer_ctls(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the level meter controls */
-       err = scarlett2_add_meter_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the sync control */
-       err = scarlett2_add_sync_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the direct monitor control */
-       err = scarlett2_add_direct_monitor_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the speaker switching control */
-       err = scarlett2_add_speaker_switch_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the talkback controls */
-       err = scarlett2_add_talkback_ctls(mixer);
-       if (err < 0)
-               return err;
-
-       /* Create the standalone control */
-       err = scarlett2_add_standalone_ctl(mixer);
-       if (err < 0)
-               return err;
-
-       /* Set up the interrupt polling */
-       err = scarlett2_init_notify(mixer);
-       if (err < 0)
-               return err;
-
-       return 0;
-}
-
-int snd_scarlett_gen2_init(struct usb_mixer_interface *mixer)
-{
-       struct snd_usb_audio *chip = mixer->chip;
-       const struct scarlett2_device_entry *entry;
-       int err;
-
-       /* only use UAC_VERSION_2 */
-       if (!mixer->protocol)
-               return 0;
-
-       /* find entry in scarlett2_devices */
-       entry = get_scarlett2_device_entry(mixer);
-       if (!entry) {
-               usb_audio_err(mixer->chip,
-                             "%s: missing device entry for %04x:%04x\n",
-                             __func__,
-                             USB_ID_VENDOR(chip->usb_id),
-                             USB_ID_PRODUCT(chip->usb_id));
-               return 0;
-       }
-
-       if (chip->setup & SCARLETT2_DISABLE) {
-               usb_audio_info(chip,
-                       "Focusrite %s Mixer Driver disabled "
-                       "by modprobe options (snd_usb_audio "
-                       "vid=0x%04x pid=0x%04x device_setup=%d)\n",
-                       entry->series_name,
-                       USB_ID_VENDOR(chip->usb_id),
-                       USB_ID_PRODUCT(chip->usb_id),
-                       SCARLETT2_DISABLE);
-               return 0;
-       }
-
-       usb_audio_info(chip,
-               "Focusrite %s Mixer Driver enabled (pid=0x%04x); "
-               "report any issues to g@b4.vu",
-               entry->series_name,
-               USB_ID_PRODUCT(chip->usb_id));
-
-       err = snd_scarlett_gen2_controls_create(mixer, entry);
-       if (err < 0)
-               usb_audio_err(mixer->chip,
-                             "Error initialising %s Mixer Driver: %d",
-                             entry->series_name,
-                             err);
-
-       return err;
-}
diff --git a/sound/usb/mixer_scarlett_gen2.h b/sound/usb/mixer_scarlett_gen2.h
deleted file mode 100644 (file)
index 668c6b0..0000000
+++ /dev/null
@@ -1,7 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __USB_MIXER_SCARLETT_GEN2_H
-#define __USB_MIXER_SCARLETT_GEN2_H
-
-int snd_scarlett_gen2_init(struct usb_mixer_interface *mixer);
-
-#endif /* __USB_MIXER_SCARLETT_GEN2_H */