Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 711 insertions, 0 deletions

diff --git a/drivers/iio/gyro/adxrs290.c b/drivers/iio/gyro/adxrs290.c
new file mode 100644
index 000000000..c7f996339
--- /dev/null
+++ b/drivers/iio/gyro/adxrs290.c
@@ -0,0 +1,711 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ADXRS290 SPI Gyroscope Driver
+ *
+ * Copyright (C) 2020 Nishant Malpani <nish.malpani25@gmail.com>
+ * Copyright (C) 2020 Analog Devices, Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define ADXRS290_ADI_ID		0xAD
+#define ADXRS290_MEMS_ID	0x1D
+#define ADXRS290_DEV_ID		0x92
+
+#define ADXRS290_REG_ADI_ID	0x00
+#define ADXRS290_REG_MEMS_ID	0x01
+#define ADXRS290_REG_DEV_ID	0x02
+#define ADXRS290_REG_REV_ID	0x03
+#define ADXRS290_REG_SN0	0x04 /* Serial Number Registers, 4 bytes */
+#define ADXRS290_REG_DATAX0	0x08 /* Roll Rate o/p Data Regs, 2 bytes */
+#define ADXRS290_REG_DATAY0	0x0A /* Pitch Rate o/p Data Regs, 2 bytes */
+#define ADXRS290_REG_TEMP0	0x0C
+#define ADXRS290_REG_POWER_CTL	0x10
+#define ADXRS290_REG_FILTER	0x11
+#define ADXRS290_REG_DATA_RDY	0x12
+
+#define ADXRS290_READ		BIT(7)
+#define ADXRS290_TSM		BIT(0)
+#define ADXRS290_MEASUREMENT	BIT(1)
+#define ADXRS290_DATA_RDY_OUT	BIT(0)
+#define ADXRS290_SYNC_MASK	GENMASK(1, 0)
+#define ADXRS290_SYNC(x)	FIELD_PREP(ADXRS290_SYNC_MASK, x)
+#define ADXRS290_LPF_MASK	GENMASK(2, 0)
+#define ADXRS290_LPF(x)		FIELD_PREP(ADXRS290_LPF_MASK, x)
+#define ADXRS290_HPF_MASK	GENMASK(7, 4)
+#define ADXRS290_HPF(x)		FIELD_PREP(ADXRS290_HPF_MASK, x)
+
+#define ADXRS290_READ_REG(reg)	(ADXRS290_READ | (reg))
+
+#define ADXRS290_MAX_TRANSITION_TIME_MS 100
+
+enum adxrs290_mode {
+	ADXRS290_MODE_STANDBY,
+	ADXRS290_MODE_MEASUREMENT,
+};
+
+enum adxrs290_scan_index {
+	ADXRS290_IDX_X,
+	ADXRS290_IDX_Y,
+	ADXRS290_IDX_TEMP,
+	ADXRS290_IDX_TS,
+};
+
+struct adxrs290_state {
+	struct spi_device	*spi;
+	/* Serialize reads and their subsequent processing */
+	struct mutex		lock;
+	enum adxrs290_mode	mode;
+	unsigned int		lpf_3db_freq_idx;
+	unsigned int		hpf_3db_freq_idx;
+	struct iio_trigger      *dready_trig;
+	/* Ensure correct alignment of timestamp when present */
+	struct {
+		s16 channels[3];
+		s64 ts __aligned(8);
+	} buffer;
+};
+
+/*
+ * Available cut-off frequencies of the low pass filter in Hz.
+ * The integer part and fractional part are represented separately.
+ */
+static const int adxrs290_lpf_3db_freq_hz_table[][2] = {
+	[0] = {480, 0},
+	[1] = {320, 0},
+	[2] = {160, 0},
+	[3] = {80, 0},
+	[4] = {56, 600000},
+	[5] = {40, 0},
+	[6] = {28, 300000},
+	[7] = {20, 0},
+};
+
+/*
+ * Available cut-off frequencies of the high pass filter in Hz.
+ * The integer part and fractional part are represented separately.
+ */
+static const int adxrs290_hpf_3db_freq_hz_table[][2] = {
+	[0] = {0, 0},
+	[1] = {0, 11000},
+	[2] = {0, 22000},
+	[3] = {0, 44000},
+	[4] = {0, 87000},
+	[5] = {0, 175000},
+	[6] = {0, 350000},
+	[7] = {0, 700000},
+	[8] = {1, 400000},
+	[9] = {2, 800000},
+	[10] = {11, 300000},
+};
+
+static int adxrs290_get_rate_data(struct iio_dev *indio_dev, const u8 cmd, int *val)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret = 0;
+	int temp;
+
+	mutex_lock(&st->lock);
+	temp = spi_w8r16(st->spi, cmd);
+	if (temp < 0) {
+		ret = temp;
+		goto err_unlock;
+	}
+
+	*val = sign_extend32(temp, 15);
+
+err_unlock:
+	mutex_unlock(&st->lock);
+	return ret;
+}
+
+static int adxrs290_get_temp_data(struct iio_dev *indio_dev, int *val)
+{
+	const u8 cmd = ADXRS290_READ_REG(ADXRS290_REG_TEMP0);
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret = 0;
+	int temp;
+
+	mutex_lock(&st->lock);
+	temp = spi_w8r16(st->spi, cmd);
+	if (temp < 0) {
+		ret = temp;
+		goto err_unlock;
+	}
+
+	/* extract lower 12 bits temperature reading */
+	*val = sign_extend32(temp, 11);
+
+err_unlock:
+	mutex_unlock(&st->lock);
+	return ret;
+}
+
+static int adxrs290_get_3db_freq(struct iio_dev *indio_dev, u8 *val, u8 *val2)
+{
+	const u8 cmd = ADXRS290_READ_REG(ADXRS290_REG_FILTER);
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret = 0;
+	short temp;
+
+	mutex_lock(&st->lock);
+	temp = spi_w8r8(st->spi, cmd);
+	if (temp < 0) {
+		ret = temp;
+		goto err_unlock;
+	}
+
+	*val = FIELD_GET(ADXRS290_LPF_MASK, temp);
+	*val2 = FIELD_GET(ADXRS290_HPF_MASK, temp);
+
+err_unlock:
+	mutex_unlock(&st->lock);
+	return ret;
+}
+
+static int adxrs290_spi_write_reg(struct spi_device *spi, const u8 reg,
+				  const u8 val)
+{
+	u8 buf[2];
+
+	buf[0] = reg;
+	buf[1] = val;
+
+	return spi_write_then_read(spi, buf, ARRAY_SIZE(buf), NULL, 0);
+}
+
+static int adxrs290_find_match(const int (*freq_tbl)[2], const int n,
+			       const int val, const int val2)
+{
+	int i;
+
+	for (i = 0; i < n; i++) {
+		if (freq_tbl[i][0] == val && freq_tbl[i][1] == val2)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
+static int adxrs290_set_filter_freq(struct iio_dev *indio_dev,
+				    const unsigned int lpf_idx,
+				    const unsigned int hpf_idx)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	u8 val;
+
+	val = ADXRS290_HPF(hpf_idx) | ADXRS290_LPF(lpf_idx);
+
+	return adxrs290_spi_write_reg(st->spi, ADXRS290_REG_FILTER, val);
+}
+
+static int adxrs290_set_mode(struct iio_dev *indio_dev, enum adxrs290_mode mode)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int val, ret;
+
+	if (st->mode == mode)
+		return 0;
+
+	mutex_lock(&st->lock);
+
+	ret = spi_w8r8(st->spi, ADXRS290_READ_REG(ADXRS290_REG_POWER_CTL));
+	if (ret < 0)
+		goto out_unlock;
+
+	val = ret;
+
+	switch (mode) {
+	case ADXRS290_MODE_STANDBY:
+		val &= ~ADXRS290_MEASUREMENT;
+		break;
+	case ADXRS290_MODE_MEASUREMENT:
+		val |= ADXRS290_MEASUREMENT;
+		break;
+	default:
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	ret = adxrs290_spi_write_reg(st->spi, ADXRS290_REG_POWER_CTL, val);
+	if (ret < 0) {
+		dev_err(&st->spi->dev, "unable to set mode: %d\n", ret);
+		goto out_unlock;
+	}
+
+	/* update cached mode */
+	st->mode = mode;
+
+out_unlock:
+	mutex_unlock(&st->lock);
+	return ret;
+}
+
+static void adxrs290_chip_off_action(void *data)
+{
+	struct iio_dev *indio_dev = data;
+
+	adxrs290_set_mode(indio_dev, ADXRS290_MODE_STANDBY);
+}
+
+static int adxrs290_initial_setup(struct iio_dev *indio_dev)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	struct spi_device *spi = st->spi;
+	int ret;
+
+	ret = adxrs290_spi_write_reg(spi, ADXRS290_REG_POWER_CTL,
+				     ADXRS290_MEASUREMENT | ADXRS290_TSM);
+	if (ret < 0)
+		return ret;
+
+	st->mode = ADXRS290_MODE_MEASUREMENT;
+
+	return devm_add_action_or_reset(&spi->dev, adxrs290_chip_off_action,
+					indio_dev);
+}
+
+static int adxrs290_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val,
+			     int *val2,
+			     long mask)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	unsigned int t;
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			ret = adxrs290_get_rate_data(indio_dev,
+						     ADXRS290_READ_REG(chan->address),
+						     val);
+			if (ret < 0)
+				break;
+
+			ret = IIO_VAL_INT;
+			break;
+		case IIO_TEMP:
+			ret = adxrs290_get_temp_data(indio_dev, val);
+			if (ret < 0)
+				break;
+
+			ret = IIO_VAL_INT;
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+
+		iio_device_release_direct_mode(indio_dev);
+		return ret;
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			/* 1 LSB = 0.005 degrees/sec */
+			*val = 0;
+			*val2 = 87266;
+			return IIO_VAL_INT_PLUS_NANO;
+		case IIO_TEMP:
+			/* 1 LSB = 0.1 degrees Celsius */
+			*val = 100;
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			t = st->lpf_3db_freq_idx;
+			*val = adxrs290_lpf_3db_freq_hz_table[t][0];
+			*val2 = adxrs290_lpf_3db_freq_hz_table[t][1];
+			return IIO_VAL_INT_PLUS_MICRO;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			t = st->hpf_3db_freq_idx;
+			*val = adxrs290_hpf_3db_freq_hz_table[t][0];
+			*val2 = adxrs290_hpf_3db_freq_hz_table[t][1];
+			return IIO_VAL_INT_PLUS_MICRO;
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int adxrs290_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      int val,
+			      int val2,
+			      long mask)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret, lpf_idx, hpf_idx;
+
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret)
+		return ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		lpf_idx = adxrs290_find_match(adxrs290_lpf_3db_freq_hz_table,
+					      ARRAY_SIZE(adxrs290_lpf_3db_freq_hz_table),
+					      val, val2);
+		if (lpf_idx < 0) {
+			ret = -EINVAL;
+			break;
+		}
+
+		/* caching the updated state of the low-pass filter */
+		st->lpf_3db_freq_idx = lpf_idx;
+		/* retrieving the current state of the high-pass filter */
+		hpf_idx = st->hpf_3db_freq_idx;
+		ret = adxrs290_set_filter_freq(indio_dev, lpf_idx, hpf_idx);
+		break;
+
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		hpf_idx = adxrs290_find_match(adxrs290_hpf_3db_freq_hz_table,
+					      ARRAY_SIZE(adxrs290_hpf_3db_freq_hz_table),
+					      val, val2);
+		if (hpf_idx < 0) {
+			ret = -EINVAL;
+			break;
+		}
+
+		/* caching the updated state of the high-pass filter */
+		st->hpf_3db_freq_idx = hpf_idx;
+		/* retrieving the current state of the low-pass filter */
+		lpf_idx = st->lpf_3db_freq_idx;
+		ret = adxrs290_set_filter_freq(indio_dev, lpf_idx, hpf_idx);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	iio_device_release_direct_mode(indio_dev);
+	return ret;
+}
+
+static int adxrs290_read_avail(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       const int **vals, int *type, int *length,
+			       long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		*vals = (const int *)adxrs290_lpf_3db_freq_hz_table;
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		/* Values are stored in a 2D matrix */
+		*length = ARRAY_SIZE(adxrs290_lpf_3db_freq_hz_table) * 2;
+
+		return IIO_AVAIL_LIST;
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		*vals = (const int *)adxrs290_hpf_3db_freq_hz_table;
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		/* Values are stored in a 2D matrix */
+		*length = ARRAY_SIZE(adxrs290_hpf_3db_freq_hz_table) * 2;
+
+		return IIO_AVAIL_LIST;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int adxrs290_reg_access_rw(struct spi_device *spi, unsigned int reg,
+				  unsigned int *readval)
+{
+	int ret;
+
+	ret = spi_w8r8(spi, ADXRS290_READ_REG(reg));
+	if (ret < 0)
+		return ret;
+
+	*readval = ret;
+
+	return 0;
+}
+
+static int adxrs290_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+			       unsigned int writeval, unsigned int *readval)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+
+	if (readval)
+		return adxrs290_reg_access_rw(st->spi, reg, readval);
+	else
+		return adxrs290_spi_write_reg(st->spi, reg, writeval);
+}
+
+static int adxrs290_data_rdy_trigger_set_state(struct iio_trigger *trig,
+					       bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret;
+	u8 val;
+
+	val = state ? ADXRS290_SYNC(ADXRS290_DATA_RDY_OUT) : 0;
+
+	ret = adxrs290_spi_write_reg(st->spi, ADXRS290_REG_DATA_RDY, val);
+	if (ret < 0)
+		dev_err(&st->spi->dev, "failed to start data rdy interrupt\n");
+
+	return ret;
+}
+
+static int adxrs290_reset_trig(struct iio_trigger *trig)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	int val;
+
+	/*
+	 * Data ready interrupt is reset after a read of the data registers.
+	 * Here, we only read the 16b DATAY registers as that marks the end of
+	 * a read of the data registers and initiates a reset for the interrupt
+	 * line.
+	 */
+	adxrs290_get_rate_data(indio_dev,
+			       ADXRS290_READ_REG(ADXRS290_REG_DATAY0), &val);
+
+	return 0;
+}
+
+static const struct iio_trigger_ops adxrs290_trigger_ops = {
+	.set_trigger_state = &adxrs290_data_rdy_trigger_set_state,
+	.validate_device = &iio_trigger_validate_own_device,
+	.try_reenable = &adxrs290_reset_trig,
+};
+
+static irqreturn_t adxrs290_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	u8 tx = ADXRS290_READ_REG(ADXRS290_REG_DATAX0);
+	int ret;
+
+	mutex_lock(&st->lock);
+
+	/* exercise a bulk data capture starting from reg DATAX0... */
+	ret = spi_write_then_read(st->spi, &tx, sizeof(tx), st->buffer.channels,
+				  sizeof(st->buffer.channels));
+	if (ret < 0)
+		goto out_unlock_notify;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &st->buffer,
+					   pf->timestamp);
+
+out_unlock_notify:
+	mutex_unlock(&st->lock);
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+#define ADXRS290_ANGL_VEL_CHANNEL(reg, axis) {				\
+	.type = IIO_ANGL_VEL,						\
+	.address = reg,							\
+	.modified = 1,							\
+	.channel2 = IIO_MOD_##axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
+	BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |		\
+	BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY),		\
+	.info_mask_shared_by_type_available =				\
+	BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |		\
+	BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY),		\
+	.scan_index = ADXRS290_IDX_##axis,				\
+	.scan_type = {                                                  \
+		.sign = 's',                                            \
+		.realbits = 16,                                         \
+		.storagebits = 16,                                      \
+		.endianness = IIO_LE,					\
+	},                                                              \
+}
+
+static const struct iio_chan_spec adxrs290_channels[] = {
+	ADXRS290_ANGL_VEL_CHANNEL(ADXRS290_REG_DATAX0, X),
+	ADXRS290_ANGL_VEL_CHANNEL(ADXRS290_REG_DATAY0, Y),
+	{
+		.type = IIO_TEMP,
+		.address = ADXRS290_REG_TEMP0,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+		BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = ADXRS290_IDX_TEMP,
+		.scan_type = {
+			.sign = 's',
+			.realbits = 12,
+			.storagebits = 16,
+			.endianness = IIO_LE,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(ADXRS290_IDX_TS),
+};
+
+static const unsigned long adxrs290_avail_scan_masks[] = {
+	BIT(ADXRS290_IDX_X) | BIT(ADXRS290_IDX_Y) | BIT(ADXRS290_IDX_TEMP),
+	0
+};
+
+static const struct iio_info adxrs290_info = {
+	.read_raw = &adxrs290_read_raw,
+	.write_raw = &adxrs290_write_raw,
+	.read_avail = &adxrs290_read_avail,
+	.debugfs_reg_access = &adxrs290_reg_access,
+};
+
+static int adxrs290_probe_trigger(struct iio_dev *indio_dev)
+{
+	struct adxrs290_state *st = iio_priv(indio_dev);
+	int ret;
+
+	if (!st->spi->irq) {
+		dev_info(&st->spi->dev, "no irq, using polling\n");
+		return 0;
+	}
+
+	st->dready_trig = devm_iio_trigger_alloc(&st->spi->dev, "%s-dev%d",
+						 indio_dev->name,
+						 indio_dev->id);
+	if (!st->dready_trig)
+		return -ENOMEM;
+
+	st->dready_trig->dev.parent = &st->spi->dev;
+	st->dready_trig->ops = &adxrs290_trigger_ops;
+	iio_trigger_set_drvdata(st->dready_trig, indio_dev);
+
+	ret = devm_request_irq(&st->spi->dev, st->spi->irq,
+			       &iio_trigger_generic_data_rdy_poll,
+			       IRQF_ONESHOT, "adxrs290_irq", st->dready_trig);
+	if (ret < 0)
+		return dev_err_probe(&st->spi->dev, ret,
+				     "request irq %d failed\n", st->spi->irq);
+
+	ret = devm_iio_trigger_register(&st->spi->dev, st->dready_trig);
+	if (ret) {
+		dev_err(&st->spi->dev, "iio trigger register failed\n");
+		return ret;
+	}
+
+	indio_dev->trig = iio_trigger_get(st->dready_trig);
+
+	return 0;
+}
+
+static int adxrs290_probe(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev;
+	struct adxrs290_state *st;
+	u8 val, val2;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->spi = spi;
+
+	indio_dev->name = "adxrs290";
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = adxrs290_channels;
+	indio_dev->num_channels = ARRAY_SIZE(adxrs290_channels);
+	indio_dev->info = &adxrs290_info;
+	indio_dev->available_scan_masks = adxrs290_avail_scan_masks;
+
+	mutex_init(&st->lock);
+
+	val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_ADI_ID));
+	if (val != ADXRS290_ADI_ID) {
+		dev_err(&spi->dev, "Wrong ADI ID 0x%02x\n", val);
+		return -ENODEV;
+	}
+
+	val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_MEMS_ID));
+	if (val != ADXRS290_MEMS_ID) {
+		dev_err(&spi->dev, "Wrong MEMS ID 0x%02x\n", val);
+		return -ENODEV;
+	}
+
+	val = spi_w8r8(spi, ADXRS290_READ_REG(ADXRS290_REG_DEV_ID));
+	if (val != ADXRS290_DEV_ID) {
+		dev_err(&spi->dev, "Wrong DEV ID 0x%02x\n", val);
+		return -ENODEV;
+	}
+
+	/* default mode the gyroscope starts in */
+	st->mode = ADXRS290_MODE_STANDBY;
+
+	/* switch to measurement mode and switch on the temperature sensor */
+	ret = adxrs290_initial_setup(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	/* max transition time to measurement mode */
+	msleep(ADXRS290_MAX_TRANSITION_TIME_MS);
+
+	ret = adxrs290_get_3db_freq(indio_dev, &val, &val2);
+	if (ret < 0)
+		return ret;
+
+	st->lpf_3db_freq_idx = val;
+	st->hpf_3db_freq_idx = val2;
+
+	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+					      &iio_pollfunc_store_time,
+					      &adxrs290_trigger_handler, NULL);
+	if (ret < 0)
+		return dev_err_probe(&spi->dev, ret,
+				     "iio triggered buffer setup failed\n");
+
+	ret = adxrs290_probe_trigger(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id adxrs290_of_match[] = {
+	{ .compatible = "adi,adxrs290" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, adxrs290_of_match);
+
+static struct spi_driver adxrs290_driver = {
+	.driver = {
+		.name = "adxrs290",
+		.of_match_table = adxrs290_of_match,
+	},
+	.probe = adxrs290_probe,
+};
+module_spi_driver(adxrs290_driver);
+
+MODULE_AUTHOR("Nishant Malpani <nish.malpani25@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices ADXRS290 Gyroscope SPI driver");
+MODULE_LICENSE("GPL");