--- /dev/null
+What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_max
+KernelVersion: 6.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Reading returns the current Degradation of Signal Reset Maximum
+ Threshold value in millivolts. Writing sets the value.
+
+What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_max_available
+KernelVersion: 6.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Reading returns the allowable voltage range for
+ in_altvoltage0_mag_rising_reset_max.
+
+What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_min
+KernelVersion: 6.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Reading returns the current Degradation of Signal Reset Minimum
+ Threshold value in millivolts. Writing sets the value.
+
+What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_min_available
+KernelVersion: 6.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Reading returns the allowable voltage range for
+ in_altvoltage0_mag_rising_reset_min.
To compile this driver as a module, choose M here: the
module will be called ad2s1200.
+
+config AD2S1210
+ tristate "Analog Devices ad2s1210 driver"
+ depends on SPI
+ depends on COMMON_CLK
+ depends on GPIOLIB || COMPILE_TEST
+ help
+ Say yes here to build support for Analog Devices spi resolver
+ to digital converters, ad2s1210, provides direct access via sysfs.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad2s1210.
+
endmenu
obj-$(CONFIG_AD2S90) += ad2s90.o
obj-$(CONFIG_AD2S1200) += ad2s1200.o
+obj-$(CONFIG_AD2S1210) += ad2s1210.o
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ad2s1210.c support for the ADI Resolver to Digital Converters: AD2S1210
+ *
+ * Copyright (c) 2010-2010 Analog Devices Inc.
+ * Copyright (c) 2023 BayLibre, SAS
+ *
+ * Device register to IIO ABI mapping:
+ *
+ * Register | Addr | IIO ABI (sysfs)
+ * ----------------------------|------|-------------------------------------------
+ * DOS Overrange Threshold | 0x89 | events/in_altvoltage0_thresh_rising_value
+ * DOS Mismatch Threshold | 0x8A | events/in_altvoltage0_mag_rising_value
+ * DOS Reset Maximum Threshold | 0x8B | events/in_altvoltage0_mag_rising_reset_max
+ * DOS Reset Minimum Threshold | 0x8C | events/in_altvoltage0_mag_rising_reset_min
+ * LOT High Threshold | 0x8D | events/in_angl1_thresh_rising_value
+ * LOT Low Threshold [1] | 0x8E | events/in_angl1_thresh_rising_hysteresis
+ * Excitation Frequency | 0x91 | out_altvoltage0_frequency
+ * Control | 0x92 | *as bit fields*
+ * Phase lock range | D5 | events/in_phase0_mag_rising_value
+ * Hysteresis | D4 | in_angl0_hysteresis
+ * Encoder resolution | D3:2 | *not implemented*
+ * Resolution | D1:0 | *device tree: assigned-resolution-bits*
+ * Soft Reset | 0xF0 | [2]
+ * Fault | 0xFF | *not implemented*
+ *
+ * [1]: The value written to the LOT low register is high value minus the
+ * hysteresis.
+ * [2]: Soft reset is performed when `out_altvoltage0_frequency` is written.
+ *
+ * Fault to event mapping:
+ *
+ * Fault | | Channel | Type | Direction
+ * ----------------------------------------|----|---------------------------------
+ * Sine/cosine inputs clipped [3] | D7 | altvoltage1 | mag | either
+ * Sine/cosine inputs below LOS | D6 | altvoltage0 | thresh | falling
+ * Sine/cosine inputs exceed DOS overrange | D5 | altvoltage0 | thresh | rising
+ * Sine/cosine inputs exceed DOS mismatch | D4 | altvoltage0 | mag | rising
+ * Tracking error exceeds LOT | D3 | angl1 | thresh | rising
+ * Velocity exceeds maximum tracking rate | D2 | anglvel0 | mag | rising
+ * Phase error exceeds phase lock range | D1 | phase0 | mag | rising
+ * Configuration parity error | D0 | *writes to kernel log*
+ *
+ * [3]: The chip does not differentiate between fault on sine vs. cosine so
+ * there will also be an event on the altvoltage2 channel.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define DRV_NAME "ad2s1210"
+
+/* control register flags */
+#define AD2S1210_ADDRESS_DATA BIT(7)
+#define AD2S1210_PHASE_LOCK_RANGE_44 BIT(5)
+#define AD2S1210_ENABLE_HYSTERESIS BIT(4)
+#define AD2S1210_SET_ENRES GENMASK(3, 2)
+#define AD2S1210_SET_RES GENMASK(1, 0)
+
+/* fault register flags */
+#define AD2S1210_FAULT_CLIP BIT(7)
+#define AD2S1210_FAULT_LOS BIT(6)
+#define AD2S1210_FAULT_DOS_OVR BIT(5)
+#define AD2S1210_FAULT_DOS_MIS BIT(4)
+#define AD2S1210_FAULT_LOT BIT(3)
+#define AD2S1210_FAULT_VELOCITY BIT(2)
+#define AD2S1210_FAULT_PHASE BIT(1)
+#define AD2S1210_FAULT_CONFIG_PARITY BIT(0)
+
+#define AD2S1210_REG_POSITION_MSB 0x80
+#define AD2S1210_REG_POSITION_LSB 0x81
+#define AD2S1210_REG_VELOCITY_MSB 0x82
+#define AD2S1210_REG_VELOCITY_LSB 0x83
+#define AD2S1210_REG_LOS_THRD 0x88
+#define AD2S1210_REG_DOS_OVR_THRD 0x89
+#define AD2S1210_REG_DOS_MIS_THRD 0x8A
+#define AD2S1210_REG_DOS_RST_MAX_THRD 0x8B
+#define AD2S1210_REG_DOS_RST_MIN_THRD 0x8C
+#define AD2S1210_REG_LOT_HIGH_THRD 0x8D
+#define AD2S1210_REG_LOT_LOW_THRD 0x8E
+#define AD2S1210_REG_EXCIT_FREQ 0x91
+#define AD2S1210_REG_CONTROL 0x92
+#define AD2S1210_REG_SOFT_RESET 0xF0
+#define AD2S1210_REG_FAULT 0xFF
+
+#define AD2S1210_MIN_CLKIN 6144000
+#define AD2S1210_MAX_CLKIN 10240000
+#define AD2S1210_MIN_EXCIT 2000
+#define AD2S1210_DEF_EXCIT 10000
+#define AD2S1210_MAX_EXCIT 20000
+#define AD2S1210_MIN_FCW 0x4
+#define AD2S1210_MAX_FCW 0x50
+
+/* 44 degrees ~= 0.767945 radians */
+#define PHASE_44_DEG_TO_RAD_INT 0
+#define PHASE_44_DEG_TO_RAD_MICRO 767945
+/* 360 degrees ~= 6.283185 radians */
+#define PHASE_360_DEG_TO_RAD_INT 6
+#define PHASE_360_DEG_TO_RAD_MICRO 283185
+
+/* Threshold voltage registers have 1 LSB == 38 mV */
+#define THRESHOLD_MILLIVOLT_PER_LSB 38
+/* max voltage for threshold registers is 0x7F * 38 mV */
+#define THRESHOLD_RANGE_STR "[0 38 4826]"
+
+#define FAULT_ONESHOT(bit, new, old) (new & bit && !(old & bit))
+
+enum ad2s1210_mode {
+ MOD_POS = 0b00,
+ MOD_VEL = 0b01,
+ MOD_RESERVED = 0b10,
+ MOD_CONFIG = 0b11,
+};
+
+enum ad2s1210_resolution {
+ AD2S1210_RES_10 = 0b00,
+ AD2S1210_RES_12 = 0b01,
+ AD2S1210_RES_14 = 0b10,
+ AD2S1210_RES_16 = 0b11,
+};
+
+struct ad2s1210_state {
+ struct mutex lock;
+ struct spi_device *sdev;
+ /** GPIO pin connected to SAMPLE line. */
+ struct gpio_desc *sample_gpio;
+ /** GPIO pins connected to A0 and A1 lines. */
+ struct gpio_descs *mode_gpios;
+ /** Used to access config registers. */
+ struct regmap *regmap;
+ /** The external oscillator frequency in Hz. */
+ unsigned long clkin_hz;
+ /** Available raw hysteresis values based on resolution. */
+ int hysteresis_available[2];
+ /** The selected resolution */
+ enum ad2s1210_resolution resolution;
+ /** Copy of fault register from the previous read. */
+ u8 prev_fault_flags;
+ /** For reading raw sample value via SPI. */
+ struct {
+ __be16 raw;
+ u8 fault;
+ } sample __aligned(IIO_DMA_MINALIGN);
+ /** Scan buffer */
+ struct {
+ __be16 chan[2];
+ /* Ensure timestamp is naturally aligned. */
+ s64 timestamp __aligned(8);
+ } scan;
+ /** SPI transmit buffer. */
+ u8 rx[2];
+ /** SPI receive buffer. */
+ u8 tx[2];
+};
+
+static int ad2s1210_set_mode(struct ad2s1210_state *st, enum ad2s1210_mode mode)
+{
+ struct gpio_descs *gpios = st->mode_gpios;
+ DECLARE_BITMAP(bitmap, 2);
+
+ bitmap[0] = mode;
+
+ return gpiod_set_array_value(gpios->ndescs, gpios->desc, gpios->info,
+ bitmap);
+}
+
+/*
+ * Writes the given data to the given register address.
+ *
+ * If the mode is configurable, the device will first be placed in
+ * configuration mode.
+ */
+static int ad2s1210_regmap_reg_write(void *context, unsigned int reg,
+ unsigned int val)
+{
+ struct ad2s1210_state *st = context;
+ struct spi_transfer xfers[] = {
+ {
+ .len = 1,
+ .rx_buf = &st->rx[0],
+ .tx_buf = &st->tx[0],
+ .cs_change = 1,
+ }, {
+ .len = 1,
+ .rx_buf = &st->rx[1],
+ .tx_buf = &st->tx[1],
+ },
+ };
+ int ret;
+
+ /* values can only be 7 bits, the MSB indicates an address */
+ if (val & ~0x7F)
+ return -EINVAL;
+
+ st->tx[0] = reg;
+ st->tx[1] = val;
+
+ ret = ad2s1210_set_mode(st, MOD_CONFIG);
+ if (ret < 0)
+ return ret;
+
+ ret = spi_sync_transfer(st->sdev, xfers, ARRAY_SIZE(xfers));
+ if (ret < 0)
+ return ret;
+
+ /* soft reset also clears the fault register */
+ if (reg == AD2S1210_REG_SOFT_RESET)
+ st->prev_fault_flags = 0;
+
+ return 0;
+}
+
+/*
+ * Reads value from one of the registers.
+ *
+ * If the mode is configurable, the device will first be placed in
+ * configuration mode.
+ */
+static int ad2s1210_regmap_reg_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ struct ad2s1210_state *st = context;
+ struct spi_transfer xfers[] = {
+ {
+ .len = 1,
+ .rx_buf = &st->rx[0],
+ .tx_buf = &st->tx[0],
+ .cs_change = 1,
+ }, {
+ .len = 1,
+ .rx_buf = &st->rx[1],
+ .tx_buf = &st->tx[1],
+ },
+ };
+ int ret;
+
+ ret = ad2s1210_set_mode(st, MOD_CONFIG);
+ if (ret < 0)
+ return ret;
+
+ st->tx[0] = reg;
+ /*
+ * Must be valid register address here otherwise this could write data.
+ * It doesn't matter which one as long as reading doesn't have side-
+ * effects.
+ */
+ st->tx[1] = AD2S1210_REG_CONTROL;
+
+ ret = spi_sync_transfer(st->sdev, xfers, ARRAY_SIZE(xfers));
+ if (ret < 0)
+ return ret;
+
+ /* reading the fault register also clears it */
+ if (reg == AD2S1210_REG_FAULT)
+ st->prev_fault_flags = 0;
+
+ /*
+ * If the D7 bit is set on any read/write register, it indicates a
+ * parity error. The fault register is read-only and the D7 bit means
+ * something else there.
+ */
+ if (reg != AD2S1210_REG_FAULT && st->rx[1] & AD2S1210_ADDRESS_DATA)
+ return -EBADMSG;
+
+ *val = st->rx[1];
+
+ return 0;
+}
+
+/*
+ * Toggles the SAMPLE line on the AD2S1210 to latch in the current position,
+ * velocity, and faults.
+ *
+ * Must be called with lock held.
+ */
+static void ad2s1210_toggle_sample_line(struct ad2s1210_state *st)
+{
+ /*
+ * Datasheet specifies minimum hold time t16 = 2 * tck + 20 ns. So the
+ * longest time needed is when CLKIN is 6.144 MHz, in which case t16
+ * ~= 350 ns. The same delay is also needed before re-asserting the
+ * SAMPLE line.
+ */
+ gpiod_set_value(st->sample_gpio, 1);
+ ndelay(350);
+ gpiod_set_value(st->sample_gpio, 0);
+ ndelay(350);
+}
+
+/*
+ * Sets the excitation frequency and performs software reset.
+ *
+ * Must be called with lock held.
+ */
+static int ad2s1210_reinit_excitation_frequency(struct ad2s1210_state *st,
+ u16 fexcit)
+{
+ /* Map resolution to settle time in milliseconds. */
+ static const int track_time_ms[] = { 10, 20, 25, 60 };
+ unsigned int ignored;
+ int ret;
+ u8 fcw;
+
+ fcw = fexcit * (1 << 15) / st->clkin_hz;
+ if (fcw < AD2S1210_MIN_FCW || fcw > AD2S1210_MAX_FCW)
+ return -ERANGE;
+
+ ret = regmap_write(st->regmap, AD2S1210_REG_EXCIT_FREQ, fcw);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Software reset reinitializes the excitation frequency output.
+ * It does not reset any of the configuration registers.
+ */
+ ret = regmap_write(st->regmap, AD2S1210_REG_SOFT_RESET, 0);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Soft reset always triggers some faults due the change in the output
+ * signal so clear the faults too. We need to delay for some time
+ * (what datasheet calls t[track]) to allow things to settle before
+ * clearing the faults.
+ */
+ msleep(track_time_ms[st->resolution] * 8192000 / st->clkin_hz);
+
+ /* Reading the fault register clears the faults. */
+ ret = regmap_read(st->regmap, AD2S1210_REG_FAULT, &ignored);
+ if (ret < 0)
+ return ret;
+
+ /* Have to toggle sample line to get fault output pins to reset. */
+ ad2s1210_toggle_sample_line(st);
+
+ return 0;
+}
+
+static void ad2s1210_push_events(struct iio_dev *indio_dev,
+ u8 flags, s64 timestamp)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ /* Sine/cosine inputs clipped */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_CLIP, flags, st->prev_fault_flags)) {
+ /*
+ * The chip does not differentiate between fault on sine vs.
+ * cosine channel so we just send an event on both channels.
+ */
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 1,
+ IIO_EV_TYPE_MAG,
+ IIO_EV_DIR_EITHER),
+ timestamp);
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 2,
+ IIO_EV_TYPE_MAG,
+ IIO_EV_DIR_EITHER),
+ timestamp);
+ }
+
+ /* Sine/cosine inputs below LOS threshold */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_LOS, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_FALLING),
+ timestamp);
+
+ /* Sine/cosine inputs exceed DOS overrange threshold */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_DOS_OVR, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ timestamp);
+
+ /* Sine/cosine inputs exceed DOS mismatch threshold */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_DOS_MIS, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
+ IIO_EV_TYPE_MAG,
+ IIO_EV_DIR_RISING),
+ timestamp);
+
+ /* Tracking error exceeds LOT threshold */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_LOT, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ANGL, 1,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ timestamp);
+
+ /* Velocity exceeds maximum tracking rate */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_VELOCITY, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_ANGL_VEL, 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ timestamp);
+
+ /* Phase error exceeds phase lock range */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_PHASE, flags, st->prev_fault_flags))
+ iio_push_event(indio_dev,
+ IIO_UNMOD_EVENT_CODE(IIO_PHASE, 0,
+ IIO_EV_TYPE_MAG,
+ IIO_EV_DIR_RISING),
+ timestamp);
+
+ /* Configuration parity error */
+ if (FAULT_ONESHOT(AD2S1210_FAULT_CONFIG_PARITY, flags,
+ st->prev_fault_flags))
+ /*
+ * Userspace should also get notified of this via error return
+ * when trying to write to any attribute that writes a register.
+ */
+ dev_err_ratelimited(&indio_dev->dev,
+ "Configuration parity error\n");
+
+ st->prev_fault_flags = flags;
+}
+
+static int ad2s1210_single_conversion(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+ s64 timestamp;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ ad2s1210_toggle_sample_line(st);
+ timestamp = iio_get_time_ns(indio_dev);
+
+ switch (chan->type) {
+ case IIO_ANGL:
+ ret = ad2s1210_set_mode(st, MOD_POS);
+ break;
+ case IIO_ANGL_VEL:
+ ret = ad2s1210_set_mode(st, MOD_VEL);
+ break;
+ default:
+ return -EINVAL;
+ }
+ if (ret < 0)
+ return ret;
+ ret = spi_read(st->sdev, &st->sample, 3);
+ if (ret < 0)
+ return ret;
+
+ switch (chan->type) {
+ case IIO_ANGL:
+ *val = be16_to_cpu(st->sample.raw);
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_ANGL_VEL:
+ *val = (s16)be16_to_cpu(st->sample.raw);
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ad2s1210_push_events(indio_dev, st->sample.fault, timestamp);
+
+ return ret;
+}
+
+static int ad2s1210_get_hysteresis(struct ad2s1210_state *st, int *val)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_test_bits(st->regmap, AD2S1210_REG_CONTROL,
+ AD2S1210_ENABLE_HYSTERESIS);
+ if (ret < 0)
+ return ret;
+
+ *val = ret << (2 * (AD2S1210_RES_16 - st->resolution));
+ return IIO_VAL_INT;
+}
+
+static int ad2s1210_set_hysteresis(struct ad2s1210_state *st, int val)
+{
+ guard(mutex)(&st->lock);
+ return regmap_update_bits(st->regmap, AD2S1210_REG_CONTROL,
+ AD2S1210_ENABLE_HYSTERESIS,
+ val ? AD2S1210_ENABLE_HYSTERESIS : 0);
+}
+
+static int ad2s1210_get_phase_lock_range(struct ad2s1210_state *st,
+ int *val, int *val2)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_test_bits(st->regmap, AD2S1210_REG_CONTROL,
+ AD2S1210_PHASE_LOCK_RANGE_44);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
+ /* 44 degrees as radians */
+ *val = PHASE_44_DEG_TO_RAD_INT;
+ *val2 = PHASE_44_DEG_TO_RAD_MICRO;
+ } else {
+ /* 360 degrees as radians */
+ *val = PHASE_360_DEG_TO_RAD_INT;
+ *val2 = PHASE_360_DEG_TO_RAD_MICRO;
+ }
+
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int ad2s1210_set_phase_lock_range(struct ad2s1210_state *st,
+ int val, int val2)
+{
+ int deg;
+
+ /* convert radians to degrees - only two allowable values */
+ if (val == PHASE_44_DEG_TO_RAD_INT && val2 == PHASE_44_DEG_TO_RAD_MICRO)
+ deg = 44;
+ else if (val == PHASE_360_DEG_TO_RAD_INT &&
+ val2 == PHASE_360_DEG_TO_RAD_MICRO)
+ deg = 360;
+ else
+ return -EINVAL;
+
+ guard(mutex)(&st->lock);
+ return regmap_update_bits(st->regmap, AD2S1210_REG_CONTROL,
+ AD2S1210_PHASE_LOCK_RANGE_44,
+ deg == 44 ? AD2S1210_PHASE_LOCK_RANGE_44 : 0);
+}
+
+/* map resolution to microradians/LSB for LOT registers */
+static const int ad2s1210_lot_threshold_urad_per_lsb[] = {
+ 6184, /* 10-bit: ~0.35 deg/LSB, 45 deg max */
+ 2473, /* 12-bit: ~0.14 deg/LSB, 18 deg max */
+ 1237, /* 14-bit: ~0.07 deg/LSB, 9 deg max */
+ 1237, /* 16-bit: same as 14-bit */
+};
+
+static int ad2s1210_get_voltage_threshold(struct ad2s1210_state *st,
+ unsigned int reg, int *val)
+{
+ unsigned int reg_val;
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_read(st->regmap, reg, ®_val);
+ if (ret < 0)
+ return ret;
+
+ *val = reg_val * THRESHOLD_MILLIVOLT_PER_LSB;
+ return IIO_VAL_INT;
+}
+
+static int ad2s1210_set_voltage_threshold(struct ad2s1210_state *st,
+ unsigned int reg, int val)
+{
+ unsigned int reg_val;
+
+ reg_val = val / THRESHOLD_MILLIVOLT_PER_LSB;
+
+ guard(mutex)(&st->lock);
+ return regmap_write(st->regmap, reg, reg_val);
+}
+
+static int ad2s1210_get_lot_high_threshold(struct ad2s1210_state *st,
+ int *val, int *val2)
+{
+ unsigned int reg_val;
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val);
+ if (ret < 0)
+ return ret;
+
+ *val = 0;
+ *val2 = reg_val * ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int ad2s1210_set_lot_high_threshold(struct ad2s1210_state *st,
+ int val, int val2)
+{
+ unsigned int high_reg_val, low_reg_val, hysteresis;
+ int ret;
+
+ /* all valid values are between 0 and pi/4 radians */
+ if (val != 0)
+ return -EINVAL;
+
+ guard(mutex)(&st->lock);
+ /*
+ * We need to read both high and low registers first so we can preserve
+ * the hysteresis.
+ */
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val);
+ if (ret < 0)
+ return ret;
+
+ hysteresis = high_reg_val - low_reg_val;
+ high_reg_val = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+ low_reg_val = high_reg_val - hysteresis;
+
+ ret = regmap_write(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, high_reg_val);
+ if (ret < 0)
+ return ret;
+
+ return regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD, low_reg_val);
+}
+
+static int ad2s1210_get_lot_low_threshold(struct ad2s1210_state *st,
+ int *val, int *val2)
+{
+ unsigned int high_reg_val, low_reg_val;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val);
+ if (ret < 0)
+ return ret;
+
+ /* sysfs value is hysteresis rather than actual low value */
+ *val = 0;
+ *val2 = (high_reg_val - low_reg_val) *
+ ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+ return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int ad2s1210_set_lot_low_threshold(struct ad2s1210_state *st,
+ int val, int val2)
+{
+ unsigned int reg_val, hysteresis;
+ int ret;
+
+ /* all valid values are between 0 and pi/4 radians */
+ if (val != 0)
+ return -EINVAL;
+
+ hysteresis = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+
+ guard(mutex)(&st->lock);
+
+ ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val);
+ if (ret < 0)
+ return ret;
+
+ return regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD,
+ reg_val - hysteresis);
+}
+
+static int ad2s1210_get_excitation_frequency(struct ad2s1210_state *st, int *val)
+{
+ unsigned int reg_val;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ ret = regmap_read(st->regmap, AD2S1210_REG_EXCIT_FREQ, ®_val);
+ if (ret < 0)
+ return ret;
+
+ *val = reg_val * st->clkin_hz / (1 << 15);
+ return IIO_VAL_INT;
+}
+
+static int ad2s1210_set_excitation_frequency(struct ad2s1210_state *st, int val)
+{
+ if (val < AD2S1210_MIN_EXCIT || val > AD2S1210_MAX_EXCIT)
+ return -EINVAL;
+
+ guard(mutex)(&st->lock);
+ return ad2s1210_reinit_excitation_frequency(st, val);
+}
+
+static const int ad2s1210_velocity_scale[] = {
+ 17089132, /* 8.192MHz / (2*pi * 2500 / 2^15) */
+ 42722830, /* 8.192MHz / (2*pi * 1000 / 2^15) */
+ 85445659, /* 8.192MHz / (2*pi * 500 / 2^15) */
+ 341782638, /* 8.192MHz / (2*pi * 125 / 2^15) */
+};
+
+static int ad2s1210_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ return ad2s1210_single_conversion(indio_dev, chan, val);
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_ANGL:
+ /* approx 0.3 arc min converted to radians */
+ *val = 0;
+ *val2 = 95874;
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_ANGL_VEL:
+ *val = st->clkin_hz;
+ *val2 = ad2s1210_velocity_scale[st->resolution];
+ return IIO_VAL_FRACTIONAL;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_FREQUENCY:
+ switch (chan->type) {
+ case IIO_ALTVOLTAGE:
+ return ad2s1210_get_excitation_frequency(st, val);
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_HYSTERESIS:
+ switch (chan->type) {
+ case IIO_ANGL:
+ return ad2s1210_get_hysteresis(st, val);
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad2s1210_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type,
+ int *length, long mask)
+{
+ static const int excitation_frequency_available[] = {
+ AD2S1210_MIN_EXCIT,
+ 250, /* step */
+ AD2S1210_MAX_EXCIT,
+ };
+
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_FREQUENCY:
+ switch (chan->type) {
+ case IIO_ALTVOLTAGE:
+ *type = IIO_VAL_INT;
+ *vals = excitation_frequency_available;
+ return IIO_AVAIL_RANGE;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_HYSTERESIS:
+ switch (chan->type) {
+ case IIO_ANGL:
+ *vals = st->hysteresis_available;
+ *type = IIO_VAL_INT;
+ *length = ARRAY_SIZE(st->hysteresis_available);
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad2s1210_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_FREQUENCY:
+ switch (chan->type) {
+ case IIO_ALTVOLTAGE:
+ return ad2s1210_set_excitation_frequency(st, val);
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_HYSTERESIS:
+ switch (chan->type) {
+ case IIO_ANGL:
+ return ad2s1210_set_hysteresis(st, val);
+ default:
+ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_event_spec ad2s1210_position_event_spec[] = {
+ {
+ /* Tracking error exceeds LOT threshold fault. */
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate =
+ /* Loss of tracking high threshold. */
+ BIT(IIO_EV_INFO_VALUE) |
+ /* Loss of tracking low threshold. */
+ BIT(IIO_EV_INFO_HYSTERESIS),
+ },
+};
+
+static const struct iio_event_spec ad2s1210_velocity_event_spec[] = {
+ {
+ /* Velocity exceeds maximum tracking rate fault. */
+ .type = IIO_EV_TYPE_MAG,
+ .dir = IIO_EV_DIR_RISING,
+ },
+};
+
+static const struct iio_event_spec ad2s1210_phase_event_spec[] = {
+ {
+ /* Phase error fault. */
+ .type = IIO_EV_TYPE_MAG,
+ .dir = IIO_EV_DIR_RISING,
+ /* Phase lock range. */
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ },
+};
+
+static const struct iio_event_spec ad2s1210_monitor_signal_event_spec[] = {
+ {
+ /* Sine/cosine below LOS threshold fault. */
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ /* Loss of signal threshold. */
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ },
+ {
+ /* Sine/cosine DOS overrange fault.*/
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ /* Degredation of signal overrange threshold. */
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ },
+ {
+ /* Sine/cosine DOS mismatch fault.*/
+ .type = IIO_EV_TYPE_MAG,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ },
+};
+
+static const struct iio_event_spec ad2s1210_sin_cos_event_spec[] = {
+ {
+ /* Sine/cosine clipping fault. */
+ .type = IIO_EV_TYPE_MAG,
+ .dir = IIO_EV_DIR_EITHER,
+ },
+};
+
+static const struct iio_chan_spec ad2s1210_channels[] = {
+ {
+ .type = IIO_ANGL,
+ .indexed = 1,
+ .channel = 0,
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 16,
+ .storagebits = 16,
+ .endianness = IIO_BE,
+ },
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_HYSTERESIS),
+ .info_mask_separate_available =
+ BIT(IIO_CHAN_INFO_HYSTERESIS),
+ }, {
+ .type = IIO_ANGL_VEL,
+ .indexed = 1,
+ .channel = 0,
+ .scan_index = 1,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 16,
+ .storagebits = 16,
+ .endianness = IIO_BE,
+ },
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .event_spec = ad2s1210_velocity_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_velocity_event_spec),
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(2),
+ {
+ /* used to configure LOT thresholds and get tracking error */
+ .type = IIO_ANGL,
+ .indexed = 1,
+ .channel = 1,
+ .scan_index = -1,
+ .event_spec = ad2s1210_position_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_position_event_spec),
+ },
+ {
+ /* used to configure phase lock range and get phase lock error */
+ .type = IIO_PHASE,
+ .indexed = 1,
+ .channel = 0,
+ .scan_index = -1,
+ .event_spec = ad2s1210_phase_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_phase_event_spec),
+ }, {
+ /* excitation frequency output */
+ .type = IIO_ALTVOLTAGE,
+ .indexed = 1,
+ .channel = 0,
+ .output = 1,
+ .scan_index = -1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_FREQUENCY),
+ .info_mask_separate_available = BIT(IIO_CHAN_INFO_FREQUENCY),
+ }, {
+ /* monitor signal */
+ .type = IIO_ALTVOLTAGE,
+ .indexed = 1,
+ .channel = 0,
+ .scan_index = -1,
+ .event_spec = ad2s1210_monitor_signal_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_monitor_signal_event_spec),
+ }, {
+ /* sine input */
+ .type = IIO_ALTVOLTAGE,
+ .indexed = 1,
+ .channel = 1,
+ .scan_index = -1,
+ .event_spec = ad2s1210_sin_cos_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_sin_cos_event_spec),
+ }, {
+ /* cosine input */
+ .type = IIO_ALTVOLTAGE,
+ .indexed = 1,
+ .channel = 2,
+ .scan_index = -1,
+ .event_spec = ad2s1210_sin_cos_event_spec,
+ .num_event_specs = ARRAY_SIZE(ad2s1210_sin_cos_event_spec),
+ },
+};
+
+static ssize_t event_attr_voltage_reg_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
+ struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
+ unsigned int value;
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_read(st->regmap, iattr->address, &value);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", value * THRESHOLD_MILLIVOLT_PER_LSB);
+}
+
+static ssize_t event_attr_voltage_reg_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
+ struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
+ u16 data;
+ int ret;
+
+ ret = kstrtou16(buf, 10, &data);
+ if (ret)
+ return -EINVAL;
+
+ guard(mutex)(&st->lock);
+ ret = regmap_write(st->regmap, iattr->address,
+ data / THRESHOLD_MILLIVOLT_PER_LSB);
+ if (ret < 0)
+ return ret;
+
+ return len;
+}
+
+static ssize_t
+in_angl1_thresh_rising_value_available_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
+ int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+
+ return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F);
+}
+
+static ssize_t
+in_angl1_thresh_rising_hysteresis_available_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
+ int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
+
+ return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F);
+}
+
+static IIO_CONST_ATTR(in_phase0_mag_rising_value_available,
+ __stringify(PHASE_44_DEG_TO_RAD_INT) "."
+ __stringify(PHASE_44_DEG_TO_RAD_MICRO) " "
+ __stringify(PHASE_360_DEG_TO_RAD_INT) "."
+ __stringify(PHASE_360_DEG_TO_RAD_MICRO));
+static IIO_CONST_ATTR(in_altvoltage0_thresh_falling_value_available,
+ THRESHOLD_RANGE_STR);
+static IIO_CONST_ATTR(in_altvoltage0_thresh_rising_value_available,
+ THRESHOLD_RANGE_STR);
+static IIO_CONST_ATTR(in_altvoltage0_mag_rising_value_available,
+ THRESHOLD_RANGE_STR);
+static IIO_DEVICE_ATTR(in_altvoltage0_mag_rising_reset_max, 0644,
+ event_attr_voltage_reg_show, event_attr_voltage_reg_store,
+ AD2S1210_REG_DOS_RST_MAX_THRD);
+static IIO_CONST_ATTR(in_altvoltage0_mag_rising_reset_max_available, THRESHOLD_RANGE_STR);
+static IIO_DEVICE_ATTR(in_altvoltage0_mag_rising_reset_min, 0644,
+ event_attr_voltage_reg_show, event_attr_voltage_reg_store,
+ AD2S1210_REG_DOS_RST_MIN_THRD);
+static IIO_CONST_ATTR(in_altvoltage0_mag_rising_reset_min_available, THRESHOLD_RANGE_STR);
+static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_value_available, 0);
+static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_hysteresis_available, 0);
+
+static struct attribute *ad2s1210_event_attributes[] = {
+ &iio_const_attr_in_phase0_mag_rising_value_available.dev_attr.attr,
+ &iio_const_attr_in_altvoltage0_thresh_falling_value_available.dev_attr.attr,
+ &iio_const_attr_in_altvoltage0_thresh_rising_value_available.dev_attr.attr,
+ &iio_const_attr_in_altvoltage0_mag_rising_value_available.dev_attr.attr,
+ &iio_dev_attr_in_altvoltage0_mag_rising_reset_max.dev_attr.attr,
+ &iio_const_attr_in_altvoltage0_mag_rising_reset_max_available.dev_attr.attr,
+ &iio_dev_attr_in_altvoltage0_mag_rising_reset_min.dev_attr.attr,
+ &iio_const_attr_in_altvoltage0_mag_rising_reset_min_available.dev_attr.attr,
+ &iio_dev_attr_in_angl1_thresh_rising_value_available.dev_attr.attr,
+ &iio_dev_attr_in_angl1_thresh_rising_hysteresis_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad2s1210_event_attribute_group = {
+ .attrs = ad2s1210_event_attributes,
+};
+
+static int ad2s1210_initial(struct ad2s1210_state *st)
+{
+ unsigned int data;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ /* Use default config register value plus resolution from devicetree. */
+ data = FIELD_PREP(AD2S1210_PHASE_LOCK_RANGE_44, 1);
+ data |= FIELD_PREP(AD2S1210_ENABLE_HYSTERESIS, 1);
+ data |= FIELD_PREP(AD2S1210_SET_ENRES, 0x3);
+ data |= FIELD_PREP(AD2S1210_SET_RES, st->resolution);
+
+ ret = regmap_write(st->regmap, AD2S1210_REG_CONTROL, data);
+ if (ret < 0)
+ return ret;
+
+ return ad2s1210_reinit_excitation_frequency(st, AD2S1210_DEF_EXCIT);
+}
+
+static int ad2s1210_read_label(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ char *label)
+{
+ if (chan->type == IIO_ANGL) {
+ if (chan->channel == 0)
+ return sprintf(label, "position\n");
+ if (chan->channel == 1)
+ return sprintf(label, "tracking error\n");
+ }
+ if (chan->type == IIO_ANGL_VEL)
+ return sprintf(label, "velocity\n");
+ if (chan->type == IIO_PHASE)
+ return sprintf(label, "synthetic reference\n");
+ if (chan->type == IIO_ALTVOLTAGE) {
+ if (chan->output)
+ return sprintf(label, "excitation\n");
+ if (chan->channel == 0)
+ return sprintf(label, "monitor signal\n");
+ if (chan->channel == 1)
+ return sprintf(label, "cosine\n");
+ if (chan->channel == 2)
+ return sprintf(label, "sine\n");
+ }
+
+ return -EINVAL;
+}
+
+static int ad2s1210_read_event_value(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info,
+ int *val, int *val2)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ switch (chan->type) {
+ case IIO_ANGL:
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ return ad2s1210_get_lot_high_threshold(st, val, val2);
+ case IIO_EV_INFO_HYSTERESIS:
+ return ad2s1210_get_lot_low_threshold(st, val, val2);
+ default:
+ return -EINVAL;
+ }
+ case IIO_ALTVOLTAGE:
+ if (chan->output)
+ return -EINVAL;
+ if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_FALLING)
+ return ad2s1210_get_voltage_threshold(st,
+ AD2S1210_REG_LOS_THRD, val);
+ if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_RISING)
+ return ad2s1210_get_voltage_threshold(st,
+ AD2S1210_REG_DOS_OVR_THRD, val);
+ if (type == IIO_EV_TYPE_MAG)
+ return ad2s1210_get_voltage_threshold(st,
+ AD2S1210_REG_DOS_MIS_THRD, val);
+ return -EINVAL;
+ case IIO_PHASE:
+ return ad2s1210_get_phase_lock_range(st, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad2s1210_write_event_value(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info,
+ int val, int val2)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ switch (chan->type) {
+ case IIO_ANGL:
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ return ad2s1210_set_lot_high_threshold(st, val, val2);
+ case IIO_EV_INFO_HYSTERESIS:
+ return ad2s1210_set_lot_low_threshold(st, val, val2);
+ default:
+ return -EINVAL;
+ }
+ case IIO_ALTVOLTAGE:
+ if (chan->output)
+ return -EINVAL;
+ if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_FALLING)
+ return ad2s1210_set_voltage_threshold(st,
+ AD2S1210_REG_LOS_THRD, val);
+ if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_RISING)
+ return ad2s1210_set_voltage_threshold(st,
+ AD2S1210_REG_DOS_OVR_THRD, val);
+ if (type == IIO_EV_TYPE_MAG)
+ return ad2s1210_set_voltage_threshold(st,
+ AD2S1210_REG_DOS_MIS_THRD, val);
+ return -EINVAL;
+ case IIO_PHASE:
+ return ad2s1210_set_phase_lock_range(st, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad2s1210_read_event_label(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ char *label)
+{
+ if (chan->type == IIO_ANGL)
+ return sprintf(label, "LOT\n");
+ if (chan->type == IIO_ANGL_VEL)
+ return sprintf(label, "max tracking rate\n");
+ if (chan->type == IIO_PHASE)
+ return sprintf(label, "phase lock\n");
+ if (chan->type == IIO_ALTVOLTAGE) {
+ if (chan->channel == 0) {
+ if (type == IIO_EV_TYPE_THRESH &&
+ dir == IIO_EV_DIR_FALLING)
+ return sprintf(label, "LOS\n");
+ if (type == IIO_EV_TYPE_THRESH &&
+ dir == IIO_EV_DIR_RISING)
+ return sprintf(label, "DOS overrange\n");
+ if (type == IIO_EV_TYPE_MAG)
+ return sprintf(label, "DOS mismatch\n");
+ }
+ if (chan->channel == 1 || chan->channel == 2)
+ return sprintf(label, "clipped\n");
+ }
+
+ return -EINVAL;
+}
+
+static int ad2s1210_debugfs_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg, unsigned int writeval,
+ unsigned int *readval)
+{
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+
+ guard(mutex)(&st->lock);
+
+ if (readval)
+ return regmap_read(st->regmap, reg, readval);
+
+ return regmap_write(st->regmap, reg, writeval);
+}
+
+static irqreturn_t ad2s1210_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad2s1210_state *st = iio_priv(indio_dev);
+ size_t chan = 0;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ memset(&st->scan, 0, sizeof(st->scan));
+ ad2s1210_toggle_sample_line(st);
+
+ if (test_bit(0, indio_dev->active_scan_mask)) {
+ ret = ad2s1210_set_mode(st, MOD_POS);
+ if (ret < 0)
+ goto error_ret;
+
+ ret = spi_read(st->sdev, &st->sample, 3);
+ if (ret < 0)
+ goto error_ret;
+
+ memcpy(&st->scan.chan[chan++], &st->sample.raw, 2);
+ }
+
+ if (test_bit(1, indio_dev->active_scan_mask)) {
+ ret = ad2s1210_set_mode(st, MOD_VEL);
+ if (ret < 0)
+ goto error_ret;
+
+ ret = spi_read(st->sdev, &st->sample, 3);
+ if (ret < 0)
+ goto error_ret;
+
+ memcpy(&st->scan.chan[chan++], &st->sample.raw, 2);
+ }
+
+ ad2s1210_push_events(indio_dev, st->sample.fault, pf->timestamp);
+ iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, pf->timestamp);
+
+error_ret:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_info ad2s1210_info = {
+ .event_attrs = &ad2s1210_event_attribute_group,
+ .read_raw = ad2s1210_read_raw,
+ .read_avail = ad2s1210_read_avail,
+ .write_raw = ad2s1210_write_raw,
+ .read_label = ad2s1210_read_label,
+ .read_event_value = ad2s1210_read_event_value,
+ .write_event_value = ad2s1210_write_event_value,
+ .read_event_label = ad2s1210_read_event_label,
+ .debugfs_reg_access = &ad2s1210_debugfs_reg_access,
+};
+
+static int ad2s1210_setup_properties(struct ad2s1210_state *st)
+{
+ struct device *dev = &st->sdev->dev;
+ u32 val;
+ int ret;
+
+ ret = device_property_read_u32(dev, "assigned-resolution-bits", &val);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "failed to read assigned-resolution-bits property\n");
+
+ if (val < 10 || val > 16)
+ return dev_err_probe(dev, -EINVAL,
+ "resolution out of range: %u\n", val);
+
+ st->resolution = (val - 10) >> 1;
+ /*
+ * These are values that correlate to the hysteresis bit in the Control
+ * register. 0 = disabled, 1 = enabled. When enabled, the actual
+ * hysteresis is +/- 1 LSB of the raw position value. Which bit is the
+ * LSB depends on the specified resolution.
+ */
+ st->hysteresis_available[0] = 0;
+ st->hysteresis_available[1] = 1 << (2 * (AD2S1210_RES_16 -
+ st->resolution));
+
+ return 0;
+}
+
+static int ad2s1210_setup_clocks(struct ad2s1210_state *st)
+{
+ struct device *dev = &st->sdev->dev;
+ struct clk *clk;
+
+ clk = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(clk))
+ return dev_err_probe(dev, PTR_ERR(clk), "failed to get clock\n");
+
+ st->clkin_hz = clk_get_rate(clk);
+ if (st->clkin_hz < AD2S1210_MIN_CLKIN || st->clkin_hz > AD2S1210_MAX_CLKIN)
+ return dev_err_probe(dev, -EINVAL,
+ "clock frequency out of range: %lu\n",
+ st->clkin_hz);
+
+ return 0;
+}
+
+static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
+{
+ struct device *dev = &st->sdev->dev;
+ struct gpio_descs *resolution_gpios;
+ DECLARE_BITMAP(bitmap, 2);
+ int ret;
+
+ /* should not be sampling on startup */
+ st->sample_gpio = devm_gpiod_get(dev, "sample", GPIOD_OUT_LOW);
+ if (IS_ERR(st->sample_gpio))
+ return dev_err_probe(dev, PTR_ERR(st->sample_gpio),
+ "failed to request sample GPIO\n");
+
+ /* both pins high means that we start in config mode */
+ st->mode_gpios = devm_gpiod_get_array(dev, "mode", GPIOD_OUT_HIGH);
+ if (IS_ERR(st->mode_gpios))
+ return dev_err_probe(dev, PTR_ERR(st->mode_gpios),
+ "failed to request mode GPIOs\n");
+
+ if (st->mode_gpios->ndescs != 2)
+ return dev_err_probe(dev, -EINVAL,
+ "requires exactly 2 mode-gpios\n");
+
+ /*
+ * If resolution gpios are provided, they get set to the required
+ * resolution, otherwise it is assumed the RES0 and RES1 pins are
+ * hard-wired to match the resolution indicated in the devicetree.
+ */
+ resolution_gpios = devm_gpiod_get_array_optional(dev, "resolution",
+ GPIOD_ASIS);
+ if (IS_ERR(resolution_gpios))
+ return dev_err_probe(dev, PTR_ERR(resolution_gpios),
+ "failed to request resolution GPIOs\n");
+
+ if (resolution_gpios) {
+ if (resolution_gpios->ndescs != 2)
+ return dev_err_probe(dev, -EINVAL,
+ "requires exactly 2 resolution-gpios\n");
+
+ bitmap[0] = st->resolution;
+
+ ret = gpiod_set_array_value(resolution_gpios->ndescs,
+ resolution_gpios->desc,
+ resolution_gpios->info,
+ bitmap);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "failed to set resolution gpios\n");
+ }
+
+ return 0;
+}
+
+static const struct regmap_range ad2s1210_regmap_readable_ranges[] = {
+ regmap_reg_range(AD2S1210_REG_POSITION_MSB, AD2S1210_REG_VELOCITY_LSB),
+ regmap_reg_range(AD2S1210_REG_LOS_THRD, AD2S1210_REG_LOT_LOW_THRD),
+ regmap_reg_range(AD2S1210_REG_EXCIT_FREQ, AD2S1210_REG_CONTROL),
+ regmap_reg_range(AD2S1210_REG_FAULT, AD2S1210_REG_FAULT),
+};
+
+static const struct regmap_access_table ad2s1210_regmap_rd_table = {
+ .yes_ranges = ad2s1210_regmap_readable_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ad2s1210_regmap_readable_ranges),
+};
+
+static const struct regmap_range ad2s1210_regmap_writeable_ranges[] = {
+ regmap_reg_range(AD2S1210_REG_LOS_THRD, AD2S1210_REG_LOT_LOW_THRD),
+ regmap_reg_range(AD2S1210_REG_EXCIT_FREQ, AD2S1210_REG_CONTROL),
+ regmap_reg_range(AD2S1210_REG_SOFT_RESET, AD2S1210_REG_SOFT_RESET),
+ regmap_reg_range(AD2S1210_REG_FAULT, AD2S1210_REG_FAULT),
+};
+
+static const struct regmap_access_table ad2s1210_regmap_wr_table = {
+ .yes_ranges = ad2s1210_regmap_writeable_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ad2s1210_regmap_writeable_ranges),
+};
+
+static int ad2s1210_setup_regmap(struct ad2s1210_state *st)
+{
+ struct device *dev = &st->sdev->dev;
+ const struct regmap_config config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .disable_locking = true,
+ .reg_read = ad2s1210_regmap_reg_read,
+ .reg_write = ad2s1210_regmap_reg_write,
+ .rd_table = &ad2s1210_regmap_rd_table,
+ .wr_table = &ad2s1210_regmap_wr_table,
+ .can_sleep = true,
+ };
+
+ st->regmap = devm_regmap_init(dev, NULL, st, &config);
+ if (IS_ERR(st->regmap))
+ return dev_err_probe(dev, PTR_ERR(st->regmap),
+ "failed to allocate register map\n");
+
+ return 0;
+}
+
+static int ad2s1210_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct ad2s1210_state *st;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+ st = iio_priv(indio_dev);
+
+ mutex_init(&st->lock);
+ st->sdev = spi;
+
+ ret = ad2s1210_setup_properties(st);
+ if (ret < 0)
+ return ret;
+
+ ret = ad2s1210_setup_clocks(st);
+ if (ret < 0)
+ return ret;
+
+ ret = ad2s1210_setup_gpios(st);
+ if (ret < 0)
+ return ret;
+
+ ret = ad2s1210_setup_regmap(st);
+ if (ret < 0)
+ return ret;
+
+ ret = ad2s1210_initial(st);
+ if (ret < 0)
+ return ret;
+
+ indio_dev->info = &ad2s1210_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = ad2s1210_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad2s1210_channels);
+ indio_dev->name = spi_get_device_id(spi)->name;
+
+ ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+ &iio_pollfunc_store_time,
+ &ad2s1210_trigger_handler, NULL);
+ if (ret < 0)
+ return dev_err_probe(&spi->dev, ret,
+ "iio triggered buffer setup failed\n");
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id ad2s1210_of_match[] = {
+ { .compatible = "adi,ad2s1210", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad2s1210_of_match);
+
+static const struct spi_device_id ad2s1210_id[] = {
+ { "ad2s1210" },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad2s1210_id);
+
+static struct spi_driver ad2s1210_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = of_match_ptr(ad2s1210_of_match),
+ },
+ .probe = ad2s1210_probe,
+ .id_table = ad2s1210_id,
+};
+module_spi_driver(ad2s1210_driver);
+
+MODULE_AUTHOR("Graff Yang <graff.yang@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices AD2S1210 Resolver to Digital SPI driver");
+MODULE_LICENSE("GPL v2");
+++ /dev/null
-What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_max
-KernelVersion: 6.7
-Contact: linux-iio@vger.kernel.org
-Description:
- Reading returns the current Degradation of Signal Reset Maximum
- Threshold value in millivolts. Writing sets the value.
-
-What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_max_available
-KernelVersion: 6.7
-Contact: linux-iio@vger.kernel.org
-Description:
- Reading returns the allowable voltage range for
- in_altvoltage0_mag_rising_reset_max.
-
-What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_min
-KernelVersion: 6.7
-Contact: linux-iio@vger.kernel.org
-Description:
- Reading returns the current Degradation of Signal Reset Minimum
- Threshold value in millivolts. Writing sets the value.
-
-What: /sys/bus/iio/devices/iio:deviceX/events/in_altvoltage0_mag_rising_reset_min_available
-KernelVersion: 6.7
-Contact: linux-iio@vger.kernel.org
-Description:
- Reading returns the allowable voltage range for
- in_altvoltage0_mag_rising_reset_min.
source "drivers/staging/iio/addac/Kconfig"
source "drivers/staging/iio/frequency/Kconfig"
source "drivers/staging/iio/impedance-analyzer/Kconfig"
-source "drivers/staging/iio/resolver/Kconfig"
endmenu
obj-y += addac/
obj-y += frequency/
obj-y += impedance-analyzer/
-obj-y += resolver/
+++ /dev/null
-# SPDX-License-Identifier: GPL-2.0
-#
-# Resolver/Synchro drivers
-#
-menu "Resolver to digital converters"
-
-config AD2S1210
- tristate "Analog Devices ad2s1210 driver"
- depends on SPI
- depends on COMMON_CLK
- depends on GPIOLIB || COMPILE_TEST
- help
- Say yes here to build support for Analog Devices spi resolver
- to digital converters, ad2s1210, provides direct access via sysfs.
-
- To compile this driver as a module, choose M here: the
- module will be called ad2s1210.
-
-endmenu
+++ /dev/null
-# SPDX-License-Identifier: GPL-2.0
-#
-# Makefile for Resolver/Synchro drivers
-#
-
-obj-$(CONFIG_AD2S1210) += ad2s1210.o
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * ad2s1210.c support for the ADI Resolver to Digital Converters: AD2S1210
- *
- * Copyright (c) 2010-2010 Analog Devices Inc.
- * Copyright (c) 2023 BayLibre, SAS
- *
- * Device register to IIO ABI mapping:
- *
- * Register | Addr | IIO ABI (sysfs)
- * ----------------------------|------|-------------------------------------------
- * DOS Overrange Threshold | 0x89 | events/in_altvoltage0_thresh_rising_value
- * DOS Mismatch Threshold | 0x8A | events/in_altvoltage0_mag_rising_value
- * DOS Reset Maximum Threshold | 0x8B | events/in_altvoltage0_mag_rising_reset_max
- * DOS Reset Minimum Threshold | 0x8C | events/in_altvoltage0_mag_rising_reset_min
- * LOT High Threshold | 0x8D | events/in_angl1_thresh_rising_value
- * LOT Low Threshold [1] | 0x8E | events/in_angl1_thresh_rising_hysteresis
- * Excitation Frequency | 0x91 | out_altvoltage0_frequency
- * Control | 0x92 | *as bit fields*
- * Phase lock range | D5 | events/in_phase0_mag_rising_value
- * Hysteresis | D4 | in_angl0_hysteresis
- * Encoder resolution | D3:2 | *not implemented*
- * Resolution | D1:0 | *device tree: assigned-resolution-bits*
- * Soft Reset | 0xF0 | [2]
- * Fault | 0xFF | *not implemented*
- *
- * [1]: The value written to the LOT low register is high value minus the
- * hysteresis.
- * [2]: Soft reset is performed when `out_altvoltage0_frequency` is written.
- *
- * Fault to event mapping:
- *
- * Fault | | Channel | Type | Direction
- * ----------------------------------------|----|---------------------------------
- * Sine/cosine inputs clipped [3] | D7 | altvoltage1 | mag | either
- * Sine/cosine inputs below LOS | D6 | altvoltage0 | thresh | falling
- * Sine/cosine inputs exceed DOS overrange | D5 | altvoltage0 | thresh | rising
- * Sine/cosine inputs exceed DOS mismatch | D4 | altvoltage0 | mag | rising
- * Tracking error exceeds LOT | D3 | angl1 | thresh | rising
- * Velocity exceeds maximum tracking rate | D2 | anglvel0 | mag | rising
- * Phase error exceeds phase lock range | D1 | phase0 | mag | rising
- * Configuration parity error | D0 | *writes to kernel log*
- *
- * [3]: The chip does not differentiate between fault on sine vs. cosine so
- * there will also be an event on the altvoltage2 channel.
- */
-
-#include <linux/bitfield.h>
-#include <linux/bits.h>
-#include <linux/cleanup.h>
-#include <linux/clk.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/gpio/consumer.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/of.h>
-#include <linux/regmap.h>
-#include <linux/slab.h>
-#include <linux/spi/spi.h>
-#include <linux/sysfs.h>
-#include <linux/types.h>
-
-#include <linux/iio/buffer.h>
-#include <linux/iio/events.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
-#include <linux/iio/trigger_consumer.h>
-#include <linux/iio/triggered_buffer.h>
-
-#define DRV_NAME "ad2s1210"
-
-/* control register flags */
-#define AD2S1210_ADDRESS_DATA BIT(7)
-#define AD2S1210_PHASE_LOCK_RANGE_44 BIT(5)
-#define AD2S1210_ENABLE_HYSTERESIS BIT(4)
-#define AD2S1210_SET_ENRES GENMASK(3, 2)
-#define AD2S1210_SET_RES GENMASK(1, 0)
-
-/* fault register flags */
-#define AD2S1210_FAULT_CLIP BIT(7)
-#define AD2S1210_FAULT_LOS BIT(6)
-#define AD2S1210_FAULT_DOS_OVR BIT(5)
-#define AD2S1210_FAULT_DOS_MIS BIT(4)
-#define AD2S1210_FAULT_LOT BIT(3)
-#define AD2S1210_FAULT_VELOCITY BIT(2)
-#define AD2S1210_FAULT_PHASE BIT(1)
-#define AD2S1210_FAULT_CONFIG_PARITY BIT(0)
-
-#define AD2S1210_REG_POSITION_MSB 0x80
-#define AD2S1210_REG_POSITION_LSB 0x81
-#define AD2S1210_REG_VELOCITY_MSB 0x82
-#define AD2S1210_REG_VELOCITY_LSB 0x83
-#define AD2S1210_REG_LOS_THRD 0x88
-#define AD2S1210_REG_DOS_OVR_THRD 0x89
-#define AD2S1210_REG_DOS_MIS_THRD 0x8A
-#define AD2S1210_REG_DOS_RST_MAX_THRD 0x8B
-#define AD2S1210_REG_DOS_RST_MIN_THRD 0x8C
-#define AD2S1210_REG_LOT_HIGH_THRD 0x8D
-#define AD2S1210_REG_LOT_LOW_THRD 0x8E
-#define AD2S1210_REG_EXCIT_FREQ 0x91
-#define AD2S1210_REG_CONTROL 0x92
-#define AD2S1210_REG_SOFT_RESET 0xF0
-#define AD2S1210_REG_FAULT 0xFF
-
-#define AD2S1210_MIN_CLKIN 6144000
-#define AD2S1210_MAX_CLKIN 10240000
-#define AD2S1210_MIN_EXCIT 2000
-#define AD2S1210_DEF_EXCIT 10000
-#define AD2S1210_MAX_EXCIT 20000
-#define AD2S1210_MIN_FCW 0x4
-#define AD2S1210_MAX_FCW 0x50
-
-/* 44 degrees ~= 0.767945 radians */
-#define PHASE_44_DEG_TO_RAD_INT 0
-#define PHASE_44_DEG_TO_RAD_MICRO 767945
-/* 360 degrees ~= 6.283185 radians */
-#define PHASE_360_DEG_TO_RAD_INT 6
-#define PHASE_360_DEG_TO_RAD_MICRO 283185
-
-/* Threshold voltage registers have 1 LSB == 38 mV */
-#define THRESHOLD_MILLIVOLT_PER_LSB 38
-/* max voltage for threshold registers is 0x7F * 38 mV */
-#define THRESHOLD_RANGE_STR "[0 38 4826]"
-
-#define FAULT_ONESHOT(bit, new, old) (new & bit && !(old & bit))
-
-enum ad2s1210_mode {
- MOD_POS = 0b00,
- MOD_VEL = 0b01,
- MOD_RESERVED = 0b10,
- MOD_CONFIG = 0b11,
-};
-
-enum ad2s1210_resolution {
- AD2S1210_RES_10 = 0b00,
- AD2S1210_RES_12 = 0b01,
- AD2S1210_RES_14 = 0b10,
- AD2S1210_RES_16 = 0b11,
-};
-
-struct ad2s1210_state {
- struct mutex lock;
- struct spi_device *sdev;
- /** GPIO pin connected to SAMPLE line. */
- struct gpio_desc *sample_gpio;
- /** GPIO pins connected to A0 and A1 lines. */
- struct gpio_descs *mode_gpios;
- /** Used to access config registers. */
- struct regmap *regmap;
- /** The external oscillator frequency in Hz. */
- unsigned long clkin_hz;
- /** Available raw hysteresis values based on resolution. */
- int hysteresis_available[2];
- /** The selected resolution */
- enum ad2s1210_resolution resolution;
- /** Copy of fault register from the previous read. */
- u8 prev_fault_flags;
- /** For reading raw sample value via SPI. */
- struct {
- __be16 raw;
- u8 fault;
- } sample __aligned(IIO_DMA_MINALIGN);
- /** Scan buffer */
- struct {
- __be16 chan[2];
- /* Ensure timestamp is naturally aligned. */
- s64 timestamp __aligned(8);
- } scan;
- /** SPI transmit buffer. */
- u8 rx[2];
- /** SPI receive buffer. */
- u8 tx[2];
-};
-
-static int ad2s1210_set_mode(struct ad2s1210_state *st, enum ad2s1210_mode mode)
-{
- struct gpio_descs *gpios = st->mode_gpios;
- DECLARE_BITMAP(bitmap, 2);
-
- bitmap[0] = mode;
-
- return gpiod_set_array_value(gpios->ndescs, gpios->desc, gpios->info,
- bitmap);
-}
-
-/*
- * Writes the given data to the given register address.
- *
- * If the mode is configurable, the device will first be placed in
- * configuration mode.
- */
-static int ad2s1210_regmap_reg_write(void *context, unsigned int reg,
- unsigned int val)
-{
- struct ad2s1210_state *st = context;
- struct spi_transfer xfers[] = {
- {
- .len = 1,
- .rx_buf = &st->rx[0],
- .tx_buf = &st->tx[0],
- .cs_change = 1,
- }, {
- .len = 1,
- .rx_buf = &st->rx[1],
- .tx_buf = &st->tx[1],
- },
- };
- int ret;
-
- /* values can only be 7 bits, the MSB indicates an address */
- if (val & ~0x7F)
- return -EINVAL;
-
- st->tx[0] = reg;
- st->tx[1] = val;
-
- ret = ad2s1210_set_mode(st, MOD_CONFIG);
- if (ret < 0)
- return ret;
-
- ret = spi_sync_transfer(st->sdev, xfers, ARRAY_SIZE(xfers));
- if (ret < 0)
- return ret;
-
- /* soft reset also clears the fault register */
- if (reg == AD2S1210_REG_SOFT_RESET)
- st->prev_fault_flags = 0;
-
- return 0;
-}
-
-/*
- * Reads value from one of the registers.
- *
- * If the mode is configurable, the device will first be placed in
- * configuration mode.
- */
-static int ad2s1210_regmap_reg_read(void *context, unsigned int reg,
- unsigned int *val)
-{
- struct ad2s1210_state *st = context;
- struct spi_transfer xfers[] = {
- {
- .len = 1,
- .rx_buf = &st->rx[0],
- .tx_buf = &st->tx[0],
- .cs_change = 1,
- }, {
- .len = 1,
- .rx_buf = &st->rx[1],
- .tx_buf = &st->tx[1],
- },
- };
- int ret;
-
- ret = ad2s1210_set_mode(st, MOD_CONFIG);
- if (ret < 0)
- return ret;
-
- st->tx[0] = reg;
- /*
- * Must be valid register address here otherwise this could write data.
- * It doesn't matter which one as long as reading doesn't have side-
- * effects.
- */
- st->tx[1] = AD2S1210_REG_CONTROL;
-
- ret = spi_sync_transfer(st->sdev, xfers, ARRAY_SIZE(xfers));
- if (ret < 0)
- return ret;
-
- /* reading the fault register also clears it */
- if (reg == AD2S1210_REG_FAULT)
- st->prev_fault_flags = 0;
-
- /*
- * If the D7 bit is set on any read/write register, it indicates a
- * parity error. The fault register is read-only and the D7 bit means
- * something else there.
- */
- if (reg != AD2S1210_REG_FAULT && st->rx[1] & AD2S1210_ADDRESS_DATA)
- return -EBADMSG;
-
- *val = st->rx[1];
-
- return 0;
-}
-
-/*
- * Toggles the SAMPLE line on the AD2S1210 to latch in the current position,
- * velocity, and faults.
- *
- * Must be called with lock held.
- */
-static void ad2s1210_toggle_sample_line(struct ad2s1210_state *st)
-{
- /*
- * Datasheet specifies minimum hold time t16 = 2 * tck + 20 ns. So the
- * longest time needed is when CLKIN is 6.144 MHz, in which case t16
- * ~= 350 ns. The same delay is also needed before re-asserting the
- * SAMPLE line.
- */
- gpiod_set_value(st->sample_gpio, 1);
- ndelay(350);
- gpiod_set_value(st->sample_gpio, 0);
- ndelay(350);
-}
-
-/*
- * Sets the excitation frequency and performs software reset.
- *
- * Must be called with lock held.
- */
-static int ad2s1210_reinit_excitation_frequency(struct ad2s1210_state *st,
- u16 fexcit)
-{
- /* Map resolution to settle time in milliseconds. */
- static const int track_time_ms[] = { 10, 20, 25, 60 };
- unsigned int ignored;
- int ret;
- u8 fcw;
-
- fcw = fexcit * (1 << 15) / st->clkin_hz;
- if (fcw < AD2S1210_MIN_FCW || fcw > AD2S1210_MAX_FCW)
- return -ERANGE;
-
- ret = regmap_write(st->regmap, AD2S1210_REG_EXCIT_FREQ, fcw);
- if (ret < 0)
- return ret;
-
- /*
- * Software reset reinitializes the excitation frequency output.
- * It does not reset any of the configuration registers.
- */
- ret = regmap_write(st->regmap, AD2S1210_REG_SOFT_RESET, 0);
- if (ret < 0)
- return ret;
-
- /*
- * Soft reset always triggers some faults due the change in the output
- * signal so clear the faults too. We need to delay for some time
- * (what datasheet calls t[track]) to allow things to settle before
- * clearing the faults.
- */
- msleep(track_time_ms[st->resolution] * 8192000 / st->clkin_hz);
-
- /* Reading the fault register clears the faults. */
- ret = regmap_read(st->regmap, AD2S1210_REG_FAULT, &ignored);
- if (ret < 0)
- return ret;
-
- /* Have to toggle sample line to get fault output pins to reset. */
- ad2s1210_toggle_sample_line(st);
-
- return 0;
-}
-
-static void ad2s1210_push_events(struct iio_dev *indio_dev,
- u8 flags, s64 timestamp)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- /* Sine/cosine inputs clipped */
- if (FAULT_ONESHOT(AD2S1210_FAULT_CLIP, flags, st->prev_fault_flags)) {
- /*
- * The chip does not differentiate between fault on sine vs.
- * cosine channel so we just send an event on both channels.
- */
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 1,
- IIO_EV_TYPE_MAG,
- IIO_EV_DIR_EITHER),
- timestamp);
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 2,
- IIO_EV_TYPE_MAG,
- IIO_EV_DIR_EITHER),
- timestamp);
- }
-
- /* Sine/cosine inputs below LOS threshold */
- if (FAULT_ONESHOT(AD2S1210_FAULT_LOS, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_FALLING),
- timestamp);
-
- /* Sine/cosine inputs exceed DOS overrange threshold */
- if (FAULT_ONESHOT(AD2S1210_FAULT_DOS_OVR, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_RISING),
- timestamp);
-
- /* Sine/cosine inputs exceed DOS mismatch threshold */
- if (FAULT_ONESHOT(AD2S1210_FAULT_DOS_MIS, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ALTVOLTAGE, 0,
- IIO_EV_TYPE_MAG,
- IIO_EV_DIR_RISING),
- timestamp);
-
- /* Tracking error exceeds LOT threshold */
- if (FAULT_ONESHOT(AD2S1210_FAULT_LOT, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ANGL, 1,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_RISING),
- timestamp);
-
- /* Velocity exceeds maximum tracking rate */
- if (FAULT_ONESHOT(AD2S1210_FAULT_VELOCITY, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_ANGL_VEL, 0,
- IIO_EV_TYPE_THRESH,
- IIO_EV_DIR_RISING),
- timestamp);
-
- /* Phase error exceeds phase lock range */
- if (FAULT_ONESHOT(AD2S1210_FAULT_PHASE, flags, st->prev_fault_flags))
- iio_push_event(indio_dev,
- IIO_UNMOD_EVENT_CODE(IIO_PHASE, 0,
- IIO_EV_TYPE_MAG,
- IIO_EV_DIR_RISING),
- timestamp);
-
- /* Configuration parity error */
- if (FAULT_ONESHOT(AD2S1210_FAULT_CONFIG_PARITY, flags,
- st->prev_fault_flags))
- /*
- * Userspace should also get notified of this via error return
- * when trying to write to any attribute that writes a register.
- */
- dev_err_ratelimited(&indio_dev->dev,
- "Configuration parity error\n");
-
- st->prev_fault_flags = flags;
-}
-
-static int ad2s1210_single_conversion(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
- s64 timestamp;
- int ret;
-
- guard(mutex)(&st->lock);
-
- ad2s1210_toggle_sample_line(st);
- timestamp = iio_get_time_ns(indio_dev);
-
- switch (chan->type) {
- case IIO_ANGL:
- ret = ad2s1210_set_mode(st, MOD_POS);
- break;
- case IIO_ANGL_VEL:
- ret = ad2s1210_set_mode(st, MOD_VEL);
- break;
- default:
- return -EINVAL;
- }
- if (ret < 0)
- return ret;
- ret = spi_read(st->sdev, &st->sample, 3);
- if (ret < 0)
- return ret;
-
- switch (chan->type) {
- case IIO_ANGL:
- *val = be16_to_cpu(st->sample.raw);
- ret = IIO_VAL_INT;
- break;
- case IIO_ANGL_VEL:
- *val = (s16)be16_to_cpu(st->sample.raw);
- ret = IIO_VAL_INT;
- break;
- default:
- return -EINVAL;
- }
-
- ad2s1210_push_events(indio_dev, st->sample.fault, timestamp);
-
- return ret;
-}
-
-static int ad2s1210_get_hysteresis(struct ad2s1210_state *st, int *val)
-{
- int ret;
-
- guard(mutex)(&st->lock);
- ret = regmap_test_bits(st->regmap, AD2S1210_REG_CONTROL,
- AD2S1210_ENABLE_HYSTERESIS);
- if (ret < 0)
- return ret;
-
- *val = ret << (2 * (AD2S1210_RES_16 - st->resolution));
- return IIO_VAL_INT;
-}
-
-static int ad2s1210_set_hysteresis(struct ad2s1210_state *st, int val)
-{
- guard(mutex)(&st->lock);
- return regmap_update_bits(st->regmap, AD2S1210_REG_CONTROL,
- AD2S1210_ENABLE_HYSTERESIS,
- val ? AD2S1210_ENABLE_HYSTERESIS : 0);
-}
-
-static int ad2s1210_get_phase_lock_range(struct ad2s1210_state *st,
- int *val, int *val2)
-{
- int ret;
-
- guard(mutex)(&st->lock);
- ret = regmap_test_bits(st->regmap, AD2S1210_REG_CONTROL,
- AD2S1210_PHASE_LOCK_RANGE_44);
- if (ret < 0)
- return ret;
-
- if (ret) {
- /* 44 degrees as radians */
- *val = PHASE_44_DEG_TO_RAD_INT;
- *val2 = PHASE_44_DEG_TO_RAD_MICRO;
- } else {
- /* 360 degrees as radians */
- *val = PHASE_360_DEG_TO_RAD_INT;
- *val2 = PHASE_360_DEG_TO_RAD_MICRO;
- }
-
- return IIO_VAL_INT_PLUS_MICRO;
-}
-
-static int ad2s1210_set_phase_lock_range(struct ad2s1210_state *st,
- int val, int val2)
-{
- int deg;
-
- /* convert radians to degrees - only two allowable values */
- if (val == PHASE_44_DEG_TO_RAD_INT && val2 == PHASE_44_DEG_TO_RAD_MICRO)
- deg = 44;
- else if (val == PHASE_360_DEG_TO_RAD_INT &&
- val2 == PHASE_360_DEG_TO_RAD_MICRO)
- deg = 360;
- else
- return -EINVAL;
-
- guard(mutex)(&st->lock);
- return regmap_update_bits(st->regmap, AD2S1210_REG_CONTROL,
- AD2S1210_PHASE_LOCK_RANGE_44,
- deg == 44 ? AD2S1210_PHASE_LOCK_RANGE_44 : 0);
-}
-
-/* map resolution to microradians/LSB for LOT registers */
-static const int ad2s1210_lot_threshold_urad_per_lsb[] = {
- 6184, /* 10-bit: ~0.35 deg/LSB, 45 deg max */
- 2473, /* 12-bit: ~0.14 deg/LSB, 18 deg max */
- 1237, /* 14-bit: ~0.07 deg/LSB, 9 deg max */
- 1237, /* 16-bit: same as 14-bit */
-};
-
-static int ad2s1210_get_voltage_threshold(struct ad2s1210_state *st,
- unsigned int reg, int *val)
-{
- unsigned int reg_val;
- int ret;
-
- guard(mutex)(&st->lock);
- ret = regmap_read(st->regmap, reg, ®_val);
- if (ret < 0)
- return ret;
-
- *val = reg_val * THRESHOLD_MILLIVOLT_PER_LSB;
- return IIO_VAL_INT;
-}
-
-static int ad2s1210_set_voltage_threshold(struct ad2s1210_state *st,
- unsigned int reg, int val)
-{
- unsigned int reg_val;
-
- reg_val = val / THRESHOLD_MILLIVOLT_PER_LSB;
-
- guard(mutex)(&st->lock);
- return regmap_write(st->regmap, reg, reg_val);
-}
-
-static int ad2s1210_get_lot_high_threshold(struct ad2s1210_state *st,
- int *val, int *val2)
-{
- unsigned int reg_val;
- int ret;
-
- guard(mutex)(&st->lock);
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val);
- if (ret < 0)
- return ret;
-
- *val = 0;
- *val2 = reg_val * ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
- return IIO_VAL_INT_PLUS_MICRO;
-}
-
-static int ad2s1210_set_lot_high_threshold(struct ad2s1210_state *st,
- int val, int val2)
-{
- unsigned int high_reg_val, low_reg_val, hysteresis;
- int ret;
-
- /* all valid values are between 0 and pi/4 radians */
- if (val != 0)
- return -EINVAL;
-
- guard(mutex)(&st->lock);
- /*
- * We need to read both high and low registers first so we can preserve
- * the hysteresis.
- */
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val);
- if (ret < 0)
- return ret;
-
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val);
- if (ret < 0)
- return ret;
-
- hysteresis = high_reg_val - low_reg_val;
- high_reg_val = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
- low_reg_val = high_reg_val - hysteresis;
-
- ret = regmap_write(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, high_reg_val);
- if (ret < 0)
- return ret;
-
- return regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD, low_reg_val);
-}
-
-static int ad2s1210_get_lot_low_threshold(struct ad2s1210_state *st,
- int *val, int *val2)
-{
- unsigned int high_reg_val, low_reg_val;
- int ret;
-
- guard(mutex)(&st->lock);
-
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val);
- if (ret < 0)
- return ret;
-
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val);
- if (ret < 0)
- return ret;
-
- /* sysfs value is hysteresis rather than actual low value */
- *val = 0;
- *val2 = (high_reg_val - low_reg_val) *
- ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
- return IIO_VAL_INT_PLUS_MICRO;
-}
-
-static int ad2s1210_set_lot_low_threshold(struct ad2s1210_state *st,
- int val, int val2)
-{
- unsigned int reg_val, hysteresis;
- int ret;
-
- /* all valid values are between 0 and pi/4 radians */
- if (val != 0)
- return -EINVAL;
-
- hysteresis = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
-
- guard(mutex)(&st->lock);
-
- ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val);
- if (ret < 0)
- return ret;
-
- return regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD,
- reg_val - hysteresis);
-}
-
-static int ad2s1210_get_excitation_frequency(struct ad2s1210_state *st, int *val)
-{
- unsigned int reg_val;
- int ret;
-
- guard(mutex)(&st->lock);
-
- ret = regmap_read(st->regmap, AD2S1210_REG_EXCIT_FREQ, ®_val);
- if (ret < 0)
- return ret;
-
- *val = reg_val * st->clkin_hz / (1 << 15);
- return IIO_VAL_INT;
-}
-
-static int ad2s1210_set_excitation_frequency(struct ad2s1210_state *st, int val)
-{
- if (val < AD2S1210_MIN_EXCIT || val > AD2S1210_MAX_EXCIT)
- return -EINVAL;
-
- guard(mutex)(&st->lock);
- return ad2s1210_reinit_excitation_frequency(st, val);
-}
-
-static const int ad2s1210_velocity_scale[] = {
- 17089132, /* 8.192MHz / (2*pi * 2500 / 2^15) */
- 42722830, /* 8.192MHz / (2*pi * 1000 / 2^15) */
- 85445659, /* 8.192MHz / (2*pi * 500 / 2^15) */
- 341782638, /* 8.192MHz / (2*pi * 125 / 2^15) */
-};
-
-static int ad2s1210_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val,
- int *val2,
- long mask)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- switch (mask) {
- case IIO_CHAN_INFO_RAW:
- return ad2s1210_single_conversion(indio_dev, chan, val);
- case IIO_CHAN_INFO_SCALE:
- switch (chan->type) {
- case IIO_ANGL:
- /* approx 0.3 arc min converted to radians */
- *val = 0;
- *val2 = 95874;
- return IIO_VAL_INT_PLUS_NANO;
- case IIO_ANGL_VEL:
- *val = st->clkin_hz;
- *val2 = ad2s1210_velocity_scale[st->resolution];
- return IIO_VAL_FRACTIONAL;
- default:
- return -EINVAL;
- }
- case IIO_CHAN_INFO_FREQUENCY:
- switch (chan->type) {
- case IIO_ALTVOLTAGE:
- return ad2s1210_get_excitation_frequency(st, val);
- default:
- return -EINVAL;
- }
- case IIO_CHAN_INFO_HYSTERESIS:
- switch (chan->type) {
- case IIO_ANGL:
- return ad2s1210_get_hysteresis(st, val);
- default:
- return -EINVAL;
- }
- default:
- return -EINVAL;
- }
-}
-
-static int ad2s1210_read_avail(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- const int **vals, int *type,
- int *length, long mask)
-{
- static const int excitation_frequency_available[] = {
- AD2S1210_MIN_EXCIT,
- 250, /* step */
- AD2S1210_MAX_EXCIT,
- };
-
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- switch (mask) {
- case IIO_CHAN_INFO_FREQUENCY:
- switch (chan->type) {
- case IIO_ALTVOLTAGE:
- *type = IIO_VAL_INT;
- *vals = excitation_frequency_available;
- return IIO_AVAIL_RANGE;
- default:
- return -EINVAL;
- }
- case IIO_CHAN_INFO_HYSTERESIS:
- switch (chan->type) {
- case IIO_ANGL:
- *vals = st->hysteresis_available;
- *type = IIO_VAL_INT;
- *length = ARRAY_SIZE(st->hysteresis_available);
- return IIO_AVAIL_LIST;
- default:
- return -EINVAL;
- }
- default:
- return -EINVAL;
- }
-}
-
-static int ad2s1210_write_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int val, int val2, long mask)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- switch (mask) {
- case IIO_CHAN_INFO_FREQUENCY:
- switch (chan->type) {
- case IIO_ALTVOLTAGE:
- return ad2s1210_set_excitation_frequency(st, val);
- default:
- return -EINVAL;
- }
- case IIO_CHAN_INFO_HYSTERESIS:
- switch (chan->type) {
- case IIO_ANGL:
- return ad2s1210_set_hysteresis(st, val);
- default:
- return -EINVAL;
- }
- default:
- return -EINVAL;
- }
-}
-
-static const struct iio_event_spec ad2s1210_position_event_spec[] = {
- {
- /* Tracking error exceeds LOT threshold fault. */
- .type = IIO_EV_TYPE_THRESH,
- .dir = IIO_EV_DIR_RISING,
- .mask_separate =
- /* Loss of tracking high threshold. */
- BIT(IIO_EV_INFO_VALUE) |
- /* Loss of tracking low threshold. */
- BIT(IIO_EV_INFO_HYSTERESIS),
- },
-};
-
-static const struct iio_event_spec ad2s1210_velocity_event_spec[] = {
- {
- /* Velocity exceeds maximum tracking rate fault. */
- .type = IIO_EV_TYPE_MAG,
- .dir = IIO_EV_DIR_RISING,
- },
-};
-
-static const struct iio_event_spec ad2s1210_phase_event_spec[] = {
- {
- /* Phase error fault. */
- .type = IIO_EV_TYPE_MAG,
- .dir = IIO_EV_DIR_RISING,
- /* Phase lock range. */
- .mask_separate = BIT(IIO_EV_INFO_VALUE),
- },
-};
-
-static const struct iio_event_spec ad2s1210_monitor_signal_event_spec[] = {
- {
- /* Sine/cosine below LOS threshold fault. */
- .type = IIO_EV_TYPE_THRESH,
- .dir = IIO_EV_DIR_FALLING,
- /* Loss of signal threshold. */
- .mask_separate = BIT(IIO_EV_INFO_VALUE),
- },
- {
- /* Sine/cosine DOS overrange fault.*/
- .type = IIO_EV_TYPE_THRESH,
- .dir = IIO_EV_DIR_RISING,
- /* Degredation of signal overrange threshold. */
- .mask_separate = BIT(IIO_EV_INFO_VALUE),
- },
- {
- /* Sine/cosine DOS mismatch fault.*/
- .type = IIO_EV_TYPE_MAG,
- .dir = IIO_EV_DIR_RISING,
- .mask_separate = BIT(IIO_EV_INFO_VALUE),
- },
-};
-
-static const struct iio_event_spec ad2s1210_sin_cos_event_spec[] = {
- {
- /* Sine/cosine clipping fault. */
- .type = IIO_EV_TYPE_MAG,
- .dir = IIO_EV_DIR_EITHER,
- },
-};
-
-static const struct iio_chan_spec ad2s1210_channels[] = {
- {
- .type = IIO_ANGL,
- .indexed = 1,
- .channel = 0,
- .scan_index = 0,
- .scan_type = {
- .sign = 'u',
- .realbits = 16,
- .storagebits = 16,
- .endianness = IIO_BE,
- },
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_SCALE) |
- BIT(IIO_CHAN_INFO_HYSTERESIS),
- .info_mask_separate_available =
- BIT(IIO_CHAN_INFO_HYSTERESIS),
- }, {
- .type = IIO_ANGL_VEL,
- .indexed = 1,
- .channel = 0,
- .scan_index = 1,
- .scan_type = {
- .sign = 's',
- .realbits = 16,
- .storagebits = 16,
- .endianness = IIO_BE,
- },
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_SCALE),
- .event_spec = ad2s1210_velocity_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_velocity_event_spec),
- },
- IIO_CHAN_SOFT_TIMESTAMP(2),
- {
- /* used to configure LOT thresholds and get tracking error */
- .type = IIO_ANGL,
- .indexed = 1,
- .channel = 1,
- .scan_index = -1,
- .event_spec = ad2s1210_position_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_position_event_spec),
- },
- {
- /* used to configure phase lock range and get phase lock error */
- .type = IIO_PHASE,
- .indexed = 1,
- .channel = 0,
- .scan_index = -1,
- .event_spec = ad2s1210_phase_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_phase_event_spec),
- }, {
- /* excitation frequency output */
- .type = IIO_ALTVOLTAGE,
- .indexed = 1,
- .channel = 0,
- .output = 1,
- .scan_index = -1,
- .info_mask_separate = BIT(IIO_CHAN_INFO_FREQUENCY),
- .info_mask_separate_available = BIT(IIO_CHAN_INFO_FREQUENCY),
- }, {
- /* monitor signal */
- .type = IIO_ALTVOLTAGE,
- .indexed = 1,
- .channel = 0,
- .scan_index = -1,
- .event_spec = ad2s1210_monitor_signal_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_monitor_signal_event_spec),
- }, {
- /* sine input */
- .type = IIO_ALTVOLTAGE,
- .indexed = 1,
- .channel = 1,
- .scan_index = -1,
- .event_spec = ad2s1210_sin_cos_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_sin_cos_event_spec),
- }, {
- /* cosine input */
- .type = IIO_ALTVOLTAGE,
- .indexed = 1,
- .channel = 2,
- .scan_index = -1,
- .event_spec = ad2s1210_sin_cos_event_spec,
- .num_event_specs = ARRAY_SIZE(ad2s1210_sin_cos_event_spec),
- },
-};
-
-static ssize_t event_attr_voltage_reg_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
- struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
- unsigned int value;
- int ret;
-
- guard(mutex)(&st->lock);
- ret = regmap_read(st->regmap, iattr->address, &value);
- if (ret < 0)
- return ret;
-
- return sprintf(buf, "%d\n", value * THRESHOLD_MILLIVOLT_PER_LSB);
-}
-
-static ssize_t event_attr_voltage_reg_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t len)
-{
- struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
- struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
- u16 data;
- int ret;
-
- ret = kstrtou16(buf, 10, &data);
- if (ret)
- return -EINVAL;
-
- guard(mutex)(&st->lock);
- ret = regmap_write(st->regmap, iattr->address,
- data / THRESHOLD_MILLIVOLT_PER_LSB);
- if (ret < 0)
- return ret;
-
- return len;
-}
-
-static ssize_t
-in_angl1_thresh_rising_value_available_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
- int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
-
- return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F);
-}
-
-static ssize_t
-in_angl1_thresh_rising_hysteresis_available_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev));
- int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution];
-
- return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F);
-}
-
-static IIO_CONST_ATTR(in_phase0_mag_rising_value_available,
- __stringify(PHASE_44_DEG_TO_RAD_INT) "."
- __stringify(PHASE_44_DEG_TO_RAD_MICRO) " "
- __stringify(PHASE_360_DEG_TO_RAD_INT) "."
- __stringify(PHASE_360_DEG_TO_RAD_MICRO));
-static IIO_CONST_ATTR(in_altvoltage0_thresh_falling_value_available,
- THRESHOLD_RANGE_STR);
-static IIO_CONST_ATTR(in_altvoltage0_thresh_rising_value_available,
- THRESHOLD_RANGE_STR);
-static IIO_CONST_ATTR(in_altvoltage0_mag_rising_value_available,
- THRESHOLD_RANGE_STR);
-static IIO_DEVICE_ATTR(in_altvoltage0_mag_rising_reset_max, 0644,
- event_attr_voltage_reg_show, event_attr_voltage_reg_store,
- AD2S1210_REG_DOS_RST_MAX_THRD);
-static IIO_CONST_ATTR(in_altvoltage0_mag_rising_reset_max_available, THRESHOLD_RANGE_STR);
-static IIO_DEVICE_ATTR(in_altvoltage0_mag_rising_reset_min, 0644,
- event_attr_voltage_reg_show, event_attr_voltage_reg_store,
- AD2S1210_REG_DOS_RST_MIN_THRD);
-static IIO_CONST_ATTR(in_altvoltage0_mag_rising_reset_min_available, THRESHOLD_RANGE_STR);
-static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_value_available, 0);
-static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_hysteresis_available, 0);
-
-static struct attribute *ad2s1210_event_attributes[] = {
- &iio_const_attr_in_phase0_mag_rising_value_available.dev_attr.attr,
- &iio_const_attr_in_altvoltage0_thresh_falling_value_available.dev_attr.attr,
- &iio_const_attr_in_altvoltage0_thresh_rising_value_available.dev_attr.attr,
- &iio_const_attr_in_altvoltage0_mag_rising_value_available.dev_attr.attr,
- &iio_dev_attr_in_altvoltage0_mag_rising_reset_max.dev_attr.attr,
- &iio_const_attr_in_altvoltage0_mag_rising_reset_max_available.dev_attr.attr,
- &iio_dev_attr_in_altvoltage0_mag_rising_reset_min.dev_attr.attr,
- &iio_const_attr_in_altvoltage0_mag_rising_reset_min_available.dev_attr.attr,
- &iio_dev_attr_in_angl1_thresh_rising_value_available.dev_attr.attr,
- &iio_dev_attr_in_angl1_thresh_rising_hysteresis_available.dev_attr.attr,
- NULL,
-};
-
-static const struct attribute_group ad2s1210_event_attribute_group = {
- .attrs = ad2s1210_event_attributes,
-};
-
-static int ad2s1210_initial(struct ad2s1210_state *st)
-{
- unsigned int data;
- int ret;
-
- guard(mutex)(&st->lock);
-
- /* Use default config register value plus resolution from devicetree. */
- data = FIELD_PREP(AD2S1210_PHASE_LOCK_RANGE_44, 1);
- data |= FIELD_PREP(AD2S1210_ENABLE_HYSTERESIS, 1);
- data |= FIELD_PREP(AD2S1210_SET_ENRES, 0x3);
- data |= FIELD_PREP(AD2S1210_SET_RES, st->resolution);
-
- ret = regmap_write(st->regmap, AD2S1210_REG_CONTROL, data);
- if (ret < 0)
- return ret;
-
- return ad2s1210_reinit_excitation_frequency(st, AD2S1210_DEF_EXCIT);
-}
-
-static int ad2s1210_read_label(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- char *label)
-{
- if (chan->type == IIO_ANGL) {
- if (chan->channel == 0)
- return sprintf(label, "position\n");
- if (chan->channel == 1)
- return sprintf(label, "tracking error\n");
- }
- if (chan->type == IIO_ANGL_VEL)
- return sprintf(label, "velocity\n");
- if (chan->type == IIO_PHASE)
- return sprintf(label, "synthetic reference\n");
- if (chan->type == IIO_ALTVOLTAGE) {
- if (chan->output)
- return sprintf(label, "excitation\n");
- if (chan->channel == 0)
- return sprintf(label, "monitor signal\n");
- if (chan->channel == 1)
- return sprintf(label, "cosine\n");
- if (chan->channel == 2)
- return sprintf(label, "sine\n");
- }
-
- return -EINVAL;
-}
-
-static int ad2s1210_read_event_value(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan,
- enum iio_event_type type,
- enum iio_event_direction dir,
- enum iio_event_info info,
- int *val, int *val2)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- switch (chan->type) {
- case IIO_ANGL:
- switch (info) {
- case IIO_EV_INFO_VALUE:
- return ad2s1210_get_lot_high_threshold(st, val, val2);
- case IIO_EV_INFO_HYSTERESIS:
- return ad2s1210_get_lot_low_threshold(st, val, val2);
- default:
- return -EINVAL;
- }
- case IIO_ALTVOLTAGE:
- if (chan->output)
- return -EINVAL;
- if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_FALLING)
- return ad2s1210_get_voltage_threshold(st,
- AD2S1210_REG_LOS_THRD, val);
- if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_RISING)
- return ad2s1210_get_voltage_threshold(st,
- AD2S1210_REG_DOS_OVR_THRD, val);
- if (type == IIO_EV_TYPE_MAG)
- return ad2s1210_get_voltage_threshold(st,
- AD2S1210_REG_DOS_MIS_THRD, val);
- return -EINVAL;
- case IIO_PHASE:
- return ad2s1210_get_phase_lock_range(st, val, val2);
- default:
- return -EINVAL;
- }
-}
-
-static int ad2s1210_write_event_value(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan,
- enum iio_event_type type,
- enum iio_event_direction dir,
- enum iio_event_info info,
- int val, int val2)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- switch (chan->type) {
- case IIO_ANGL:
- switch (info) {
- case IIO_EV_INFO_VALUE:
- return ad2s1210_set_lot_high_threshold(st, val, val2);
- case IIO_EV_INFO_HYSTERESIS:
- return ad2s1210_set_lot_low_threshold(st, val, val2);
- default:
- return -EINVAL;
- }
- case IIO_ALTVOLTAGE:
- if (chan->output)
- return -EINVAL;
- if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_FALLING)
- return ad2s1210_set_voltage_threshold(st,
- AD2S1210_REG_LOS_THRD, val);
- if (type == IIO_EV_TYPE_THRESH && dir == IIO_EV_DIR_RISING)
- return ad2s1210_set_voltage_threshold(st,
- AD2S1210_REG_DOS_OVR_THRD, val);
- if (type == IIO_EV_TYPE_MAG)
- return ad2s1210_set_voltage_threshold(st,
- AD2S1210_REG_DOS_MIS_THRD, val);
- return -EINVAL;
- case IIO_PHASE:
- return ad2s1210_set_phase_lock_range(st, val, val2);
- default:
- return -EINVAL;
- }
-}
-
-static int ad2s1210_read_event_label(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- enum iio_event_type type,
- enum iio_event_direction dir,
- char *label)
-{
- if (chan->type == IIO_ANGL)
- return sprintf(label, "LOT\n");
- if (chan->type == IIO_ANGL_VEL)
- return sprintf(label, "max tracking rate\n");
- if (chan->type == IIO_PHASE)
- return sprintf(label, "phase lock\n");
- if (chan->type == IIO_ALTVOLTAGE) {
- if (chan->channel == 0) {
- if (type == IIO_EV_TYPE_THRESH &&
- dir == IIO_EV_DIR_FALLING)
- return sprintf(label, "LOS\n");
- if (type == IIO_EV_TYPE_THRESH &&
- dir == IIO_EV_DIR_RISING)
- return sprintf(label, "DOS overrange\n");
- if (type == IIO_EV_TYPE_MAG)
- return sprintf(label, "DOS mismatch\n");
- }
- if (chan->channel == 1 || chan->channel == 2)
- return sprintf(label, "clipped\n");
- }
-
- return -EINVAL;
-}
-
-static int ad2s1210_debugfs_reg_access(struct iio_dev *indio_dev,
- unsigned int reg, unsigned int writeval,
- unsigned int *readval)
-{
- struct ad2s1210_state *st = iio_priv(indio_dev);
-
- guard(mutex)(&st->lock);
-
- if (readval)
- return regmap_read(st->regmap, reg, readval);
-
- return regmap_write(st->regmap, reg, writeval);
-}
-
-static irqreturn_t ad2s1210_trigger_handler(int irq, void *p)
-{
- struct iio_poll_func *pf = p;
- struct iio_dev *indio_dev = pf->indio_dev;
- struct ad2s1210_state *st = iio_priv(indio_dev);
- size_t chan = 0;
- int ret;
-
- guard(mutex)(&st->lock);
-
- memset(&st->scan, 0, sizeof(st->scan));
- ad2s1210_toggle_sample_line(st);
-
- if (test_bit(0, indio_dev->active_scan_mask)) {
- ret = ad2s1210_set_mode(st, MOD_POS);
- if (ret < 0)
- goto error_ret;
-
- ret = spi_read(st->sdev, &st->sample, 3);
- if (ret < 0)
- goto error_ret;
-
- memcpy(&st->scan.chan[chan++], &st->sample.raw, 2);
- }
-
- if (test_bit(1, indio_dev->active_scan_mask)) {
- ret = ad2s1210_set_mode(st, MOD_VEL);
- if (ret < 0)
- goto error_ret;
-
- ret = spi_read(st->sdev, &st->sample, 3);
- if (ret < 0)
- goto error_ret;
-
- memcpy(&st->scan.chan[chan++], &st->sample.raw, 2);
- }
-
- ad2s1210_push_events(indio_dev, st->sample.fault, pf->timestamp);
- iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, pf->timestamp);
-
-error_ret:
- iio_trigger_notify_done(indio_dev->trig);
-
- return IRQ_HANDLED;
-}
-
-static const struct iio_info ad2s1210_info = {
- .event_attrs = &ad2s1210_event_attribute_group,
- .read_raw = ad2s1210_read_raw,
- .read_avail = ad2s1210_read_avail,
- .write_raw = ad2s1210_write_raw,
- .read_label = ad2s1210_read_label,
- .read_event_value = ad2s1210_read_event_value,
- .write_event_value = ad2s1210_write_event_value,
- .read_event_label = ad2s1210_read_event_label,
- .debugfs_reg_access = &ad2s1210_debugfs_reg_access,
-};
-
-static int ad2s1210_setup_properties(struct ad2s1210_state *st)
-{
- struct device *dev = &st->sdev->dev;
- u32 val;
- int ret;
-
- ret = device_property_read_u32(dev, "assigned-resolution-bits", &val);
- if (ret < 0)
- return dev_err_probe(dev, ret,
- "failed to read assigned-resolution-bits property\n");
-
- if (val < 10 || val > 16)
- return dev_err_probe(dev, -EINVAL,
- "resolution out of range: %u\n", val);
-
- st->resolution = (val - 10) >> 1;
- /*
- * These are values that correlate to the hysteresis bit in the Control
- * register. 0 = disabled, 1 = enabled. When enabled, the actual
- * hysteresis is +/- 1 LSB of the raw position value. Which bit is the
- * LSB depends on the specified resolution.
- */
- st->hysteresis_available[0] = 0;
- st->hysteresis_available[1] = 1 << (2 * (AD2S1210_RES_16 -
- st->resolution));
-
- return 0;
-}
-
-static int ad2s1210_setup_clocks(struct ad2s1210_state *st)
-{
- struct device *dev = &st->sdev->dev;
- struct clk *clk;
-
- clk = devm_clk_get_enabled(dev, NULL);
- if (IS_ERR(clk))
- return dev_err_probe(dev, PTR_ERR(clk), "failed to get clock\n");
-
- st->clkin_hz = clk_get_rate(clk);
- if (st->clkin_hz < AD2S1210_MIN_CLKIN || st->clkin_hz > AD2S1210_MAX_CLKIN)
- return dev_err_probe(dev, -EINVAL,
- "clock frequency out of range: %lu\n",
- st->clkin_hz);
-
- return 0;
-}
-
-static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
-{
- struct device *dev = &st->sdev->dev;
- struct gpio_descs *resolution_gpios;
- DECLARE_BITMAP(bitmap, 2);
- int ret;
-
- /* should not be sampling on startup */
- st->sample_gpio = devm_gpiod_get(dev, "sample", GPIOD_OUT_LOW);
- if (IS_ERR(st->sample_gpio))
- return dev_err_probe(dev, PTR_ERR(st->sample_gpio),
- "failed to request sample GPIO\n");
-
- /* both pins high means that we start in config mode */
- st->mode_gpios = devm_gpiod_get_array(dev, "mode", GPIOD_OUT_HIGH);
- if (IS_ERR(st->mode_gpios))
- return dev_err_probe(dev, PTR_ERR(st->mode_gpios),
- "failed to request mode GPIOs\n");
-
- if (st->mode_gpios->ndescs != 2)
- return dev_err_probe(dev, -EINVAL,
- "requires exactly 2 mode-gpios\n");
-
- /*
- * If resolution gpios are provided, they get set to the required
- * resolution, otherwise it is assumed the RES0 and RES1 pins are
- * hard-wired to match the resolution indicated in the devicetree.
- */
- resolution_gpios = devm_gpiod_get_array_optional(dev, "resolution",
- GPIOD_ASIS);
- if (IS_ERR(resolution_gpios))
- return dev_err_probe(dev, PTR_ERR(resolution_gpios),
- "failed to request resolution GPIOs\n");
-
- if (resolution_gpios) {
- if (resolution_gpios->ndescs != 2)
- return dev_err_probe(dev, -EINVAL,
- "requires exactly 2 resolution-gpios\n");
-
- bitmap[0] = st->resolution;
-
- ret = gpiod_set_array_value(resolution_gpios->ndescs,
- resolution_gpios->desc,
- resolution_gpios->info,
- bitmap);
- if (ret < 0)
- return dev_err_probe(dev, ret,
- "failed to set resolution gpios\n");
- }
-
- return 0;
-}
-
-static const struct regmap_range ad2s1210_regmap_readable_ranges[] = {
- regmap_reg_range(AD2S1210_REG_POSITION_MSB, AD2S1210_REG_VELOCITY_LSB),
- regmap_reg_range(AD2S1210_REG_LOS_THRD, AD2S1210_REG_LOT_LOW_THRD),
- regmap_reg_range(AD2S1210_REG_EXCIT_FREQ, AD2S1210_REG_CONTROL),
- regmap_reg_range(AD2S1210_REG_FAULT, AD2S1210_REG_FAULT),
-};
-
-static const struct regmap_access_table ad2s1210_regmap_rd_table = {
- .yes_ranges = ad2s1210_regmap_readable_ranges,
- .n_yes_ranges = ARRAY_SIZE(ad2s1210_regmap_readable_ranges),
-};
-
-static const struct regmap_range ad2s1210_regmap_writeable_ranges[] = {
- regmap_reg_range(AD2S1210_REG_LOS_THRD, AD2S1210_REG_LOT_LOW_THRD),
- regmap_reg_range(AD2S1210_REG_EXCIT_FREQ, AD2S1210_REG_CONTROL),
- regmap_reg_range(AD2S1210_REG_SOFT_RESET, AD2S1210_REG_SOFT_RESET),
- regmap_reg_range(AD2S1210_REG_FAULT, AD2S1210_REG_FAULT),
-};
-
-static const struct regmap_access_table ad2s1210_regmap_wr_table = {
- .yes_ranges = ad2s1210_regmap_writeable_ranges,
- .n_yes_ranges = ARRAY_SIZE(ad2s1210_regmap_writeable_ranges),
-};
-
-static int ad2s1210_setup_regmap(struct ad2s1210_state *st)
-{
- struct device *dev = &st->sdev->dev;
- const struct regmap_config config = {
- .reg_bits = 8,
- .val_bits = 8,
- .disable_locking = true,
- .reg_read = ad2s1210_regmap_reg_read,
- .reg_write = ad2s1210_regmap_reg_write,
- .rd_table = &ad2s1210_regmap_rd_table,
- .wr_table = &ad2s1210_regmap_wr_table,
- .can_sleep = true,
- };
-
- st->regmap = devm_regmap_init(dev, NULL, st, &config);
- if (IS_ERR(st->regmap))
- return dev_err_probe(dev, PTR_ERR(st->regmap),
- "failed to allocate register map\n");
-
- return 0;
-}
-
-static int ad2s1210_probe(struct spi_device *spi)
-{
- struct iio_dev *indio_dev;
- struct ad2s1210_state *st;
- int ret;
-
- indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
- if (!indio_dev)
- return -ENOMEM;
- st = iio_priv(indio_dev);
-
- mutex_init(&st->lock);
- st->sdev = spi;
-
- ret = ad2s1210_setup_properties(st);
- if (ret < 0)
- return ret;
-
- ret = ad2s1210_setup_clocks(st);
- if (ret < 0)
- return ret;
-
- ret = ad2s1210_setup_gpios(st);
- if (ret < 0)
- return ret;
-
- ret = ad2s1210_setup_regmap(st);
- if (ret < 0)
- return ret;
-
- ret = ad2s1210_initial(st);
- if (ret < 0)
- return ret;
-
- indio_dev->info = &ad2s1210_info;
- indio_dev->modes = INDIO_DIRECT_MODE;
- indio_dev->channels = ad2s1210_channels;
- indio_dev->num_channels = ARRAY_SIZE(ad2s1210_channels);
- indio_dev->name = spi_get_device_id(spi)->name;
-
- ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
- &iio_pollfunc_store_time,
- &ad2s1210_trigger_handler, NULL);
- if (ret < 0)
- return dev_err_probe(&spi->dev, ret,
- "iio triggered buffer setup failed\n");
-
- return devm_iio_device_register(&spi->dev, indio_dev);
-}
-
-static const struct of_device_id ad2s1210_of_match[] = {
- { .compatible = "adi,ad2s1210", },
- { }
-};
-MODULE_DEVICE_TABLE(of, ad2s1210_of_match);
-
-static const struct spi_device_id ad2s1210_id[] = {
- { "ad2s1210" },
- {}
-};
-MODULE_DEVICE_TABLE(spi, ad2s1210_id);
-
-static struct spi_driver ad2s1210_driver = {
- .driver = {
- .name = DRV_NAME,
- .of_match_table = of_match_ptr(ad2s1210_of_match),
- },
- .probe = ad2s1210_probe,
- .id_table = ad2s1210_id,
-};
-module_spi_driver(ad2s1210_driver);
-
-MODULE_AUTHOR("Graff Yang <graff.yang@gmail.com>");
-MODULE_DESCRIPTION("Analog Devices AD2S1210 Resolver to Digital SPI driver");
-MODULE_LICENSE("GPL v2");
projects / linux.git / commitdiff