ALSA: scarlett2: Add support for Air Presence + Drive option

Extend the existing "air" option support from Scarlett Gen 3, which
had two states (off/on), to accommodate Scarlett Gen 4's new state:
Presence + Drive.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/a9ccda7222842a72e4ce7aa258614ff45248bb16.1703612638.git.g@b4.vu

diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c
index a0f1f47fb817b6eb7d6fbe01209891f3775900bd..1a955a6decf3eca3dd8a18956b71ad0eaa96acd3 100644 (file)
--- a/sound/usb/mixer_scarlett2.c
+++ b/sound/usb/mixer_scarlett2.c
@@ -647,6 +647,12 @@ struct scarlett2_device_info {
        /* the first input with an air control (0-based) */
        u8 air_input_first;
 
+       /* number of additional air options
+        * 0 for air presence only (Gen 3)
+        * 1 for air presence+drive (Gen 4)
+        */
+       u8 air_option;
+
        /* the number of phantom (48V) software switchable controls */
        u8 phantom_count;
 
@@ -3022,7 +3028,7 @@ static int scarlett2_air_ctl_put(struct snd_kcontrol *kctl,
        }
 
        oval = private->air_switch[index];
-       val = !!ucontrol->value.integer.value[0];
+       val = ucontrol->value.integer.value[0];
 
        if (oval == val)
                goto unlock;
@@ -3040,12 +3046,31 @@ unlock:
        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,
+static int scarlett2_air_with_drive_ctl_info(
+       struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const values[3] = {
+               "Off", "Presence", "Presence + Drive"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, 3, values);
+}
+
+static const struct snd_kcontrol_new scarlett2_air_ctl[2] = {
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+               .name = "",
+               .info = snd_ctl_boolean_mono_info,
+               .get  = scarlett2_air_ctl_get,
+               .put  = scarlett2_air_ctl_put,
+       },
+       {
+               .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+               .name = "",
+               .info = scarlett2_air_with_drive_ctl_info,
+               .get  = scarlett2_air_ctl_get,
+               .put  = scarlett2_air_ctl_put,
+       }
 };
 
 /*** Phantom Switch Controls ***/
@@ -3839,9 +3864,10 @@ static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
        /* Add input air controls */
        for (i = 0; i < info->air_input_count; i++) {
                snprintf(s, sizeof(s), fmt, i + 1 + info->air_input_first,
-                        "Air", "Switch");
-               err = scarlett2_add_new_ctl(mixer, &scarlett2_air_ctl,
-                                           i, 1, s, &private->air_ctls[i]);
+                        "Air", info->air_option ? "Enum" : "Switch");
+               err = scarlett2_add_new_ctl(
+                       mixer, &scarlett2_air_ctl[info->air_option],
+                       i, 1, s, &private->air_ctls[i]);
                if (err < 0)
                        return err;
        }