[v2,2/5] iio: gyro: fxas2100x: add core driver for fxas2100x gyroscope

Message ID 20190205174333.17672-3-rui.silva@linaro.org
State New
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Series
  • iio: gyro: add fxas2100x driver
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Commit Message

Rui Miguel Silva Feb. 5, 2019, 5:43 p.m.
This adds core support for the NXP fxas2100x Tri-axis gyroscope, using
the iio subsystem. It supports PM operations, axis reading, temperature, scale
factor of the axis, high pass and low pass filtering, and sampling frequency
selection.

It will have extras modules to support the communication over i2c
and spi.

Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>

---
 drivers/iio/gyro/Kconfig          |  11 +
 drivers/iio/gyro/Makefile         |   1 +
 drivers/iio/gyro/fxas2100x.h      | 151 +++++
 drivers/iio/gyro/fxas2100x_core.c | 931 ++++++++++++++++++++++++++++++
 4 files changed, 1094 insertions(+)
 create mode 100644 drivers/iio/gyro/fxas2100x.h
 create mode 100644 drivers/iio/gyro/fxas2100x_core.c

-- 
2.20.1

Comments

Jonathan Cameron Feb. 6, 2019, 1:18 p.m. | #1
On Tue, 5 Feb 2019 17:43:30 +0000
Rui Miguel Silva <rui.silva@linaro.org> wrote:

> This adds core support for the NXP fxas2100x Tri-axis gyroscope, using

> the iio subsystem. It supports PM operations, axis reading, temperature, scale

> factor of the axis, high pass and low pass filtering, and sampling frequency

> selection.

> 

> It will have extras modules to support the communication over i2c

> and spi.

> 

> Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>

One quick general comment. 

Please don't use wildcards in driver names. It goes wrong far to often.
The convention is pick a part that is supported (usually the first one)
and name it after that.

Some quick review comments inline.  I'll take a closer look at v3 but won't
get back to this until at least the weekend.

Jonathan

> ---

>  drivers/iio/gyro/Kconfig          |  11 +

>  drivers/iio/gyro/Makefile         |   1 +

>  drivers/iio/gyro/fxas2100x.h      | 151 +++++

>  drivers/iio/gyro/fxas2100x_core.c | 931 ++++++++++++++++++++++++++++++

>  4 files changed, 1094 insertions(+)

>  create mode 100644 drivers/iio/gyro/fxas2100x.h

>  create mode 100644 drivers/iio/gyro/fxas2100x_core.c

> 

> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig

> index 3126cf05e6b9..c168aa63de3b 100644

> --- a/drivers/iio/gyro/Kconfig

> +++ b/drivers/iio/gyro/Kconfig

> @@ -73,6 +73,17 @@ config BMG160_SPI

>  	tristate

>  	select REGMAP_SPI

>  

> +config FXAS2100X

> +	tristate "NXP FXAS2100X Gyro Sensor"

> +	select IIO_BUFFER

> +	select IIO_TRIGGERED_BUFFER

> +	help

> +	  Say yes here to build support for NXP FXAS2100X family Tri-axis Gyro

> +	  Sensor driver connected via I2C or SPI.

> +

> +	  This driver can also be built as a module.  If so, the module

> +	  will be called fxas2100x_i2c or fxas2100x_spi.

> +

>  config HID_SENSOR_GYRO_3D

>  	depends on HID_SENSOR_HUB

>  	select IIO_BUFFER

> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile

> index 295ec780c4eb..9e2395185a6e 100644

> --- a/drivers/iio/gyro/Makefile

> +++ b/drivers/iio/gyro/Makefile

> @@ -12,6 +12,7 @@ obj-$(CONFIG_ADXRS450) += adxrs450.o

>  obj-$(CONFIG_BMG160) += bmg160_core.o

>  obj-$(CONFIG_BMG160_I2C) += bmg160_i2c.o

>  obj-$(CONFIG_BMG160_SPI) += bmg160_spi.o

> +obj-$(CONFIG_FXAS2100X) += fxas2100x_core.o

>  

>  obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o

>  

> diff --git a/drivers/iio/gyro/fxas2100x.h b/drivers/iio/gyro/fxas2100x.h

> new file mode 100644

> index 000000000000..2b503196337f

> --- /dev/null

> +++ b/drivers/iio/gyro/fxas2100x.h

> @@ -0,0 +1,151 @@

> +/* SPDX-License-Identifier: GPL-2.0 */

> +/*

> + * Driver for NXP FXAS2100x Gyroscope - Header

> + *

> + * Copyright (C) 2019 Linaro Ltd.

> + *

> + */

> +

> +#ifndef FXAS2100X_H_

> +#define FXAS2100X_H_

> +

> +#include <linux/regmap.h>

> +

> +#define FXAS2100X_REG_STATUS		0x00

> +#define FXAS2100X_REG_OUT_X_MSB		0x01

> +#define FXAS2100X_REG_OUT_X_LSB		0x02

> +#define FXAS2100X_REG_OUT_Y_MSB		0x03

> +#define FXAS2100X_REG_OUT_Y_LSB		0x04

> +#define FXAS2100X_REG_OUT_Z_MSB		0x05

> +#define FXAS2100X_REG_OUT_Z_LSB		0x06

> +#define FXAS2100X_REG_DR_STATUS		0x07

> +#define FXAS2100X_REG_F_STATUS		0x08

> +#define FXAS2100X_REG_F_SETUP		0x09

> +#define FXAS2100X_REG_F_EVENT		0x0A

> +#define FXAS2100X_REG_INT_SRC_FLAG	0x0B

> +#define FXAS2100X_REG_WHO_AM_I		0x0C

> +#define FXAS2100X_REG_CTRL0		0x0D

> +#define FXAS2100X_REG_RT_CFG		0x0E

> +#define FXAS2100X_REG_RT_SRC		0x0F

> +#define FXAS2100X_REG_RT_THS		0x10

> +#define FXAS2100X_REG_RT_COUNT		0x11

> +#define FXAS2100X_REG_TEMP		0x12

> +#define FXAS2100X_REG_CTRL1		0x13

> +#define FXAS2100X_REG_CTRL2		0x14

> +#define FXAS2100X_REG_CTRL3		0x15

> +

> +enum fxas2100x_fields {

> +	F_DR_STATUS,

> +	F_OUT_X_MSB,

> +	F_OUT_X_LSB,

> +	F_OUT_Y_MSB,

> +	F_OUT_Y_LSB,

> +	F_OUT_Z_MSB,

> +	F_OUT_Z_LSB,

> +	/* DR_STATUS */

> +	F_ZYX_OW, F_Z_OW, F_Y_OW, F_X_OW, F_ZYX_DR, F_Z_DR, F_Y_DR, F_X_DR,

> +	/* F_STATUS */

> +	F_OVF, F_WMKF, F_CNT,

> +	/* F_SETUP */

> +	F_MODE, F_WMRK,

> +	/* F_EVENT */

> +	F_EVENT, FE_TIME,

> +	/* INT_SOURCE_FLAG */

> +	F_BOOTEND, F_SRC_FIFO, F_SRC_RT, F_SRC_DRDY,

> +	/* WHO_AM_I */

> +	F_WHO_AM_I,

> +	/* CTRL_REG0 */

> +	F_BW, F_SPIW, F_SEL, F_HPF_EN, F_FS,

> +	/* RT_CFG */

> +	F_ELE, F_ZTEFE, F_YTEFE, F_XTEFE,

> +	/* RT_SRC */

> +	F_EA, F_ZRT, F_ZRT_POL, F_YRT, F_YRT_POL, F_XRT, F_XRT_POL,

> +	/* RT_THS */

> +	F_DBCNTM, F_THS,

> +	/* RT_COUNT */

> +	F_RT_COUNT,

> +	/* TEMP */

> +	F_TEMP,

> +	/* CTRL_REG1 */

> +	F_RST, F_ST, F_DR, F_ACTIVE, F_READY,

> +	/* CTRL_REG2 */

> +	F_INT_CFG_FIFO, F_INT_EN_FIFO, F_INT_CFG_RT, F_INT_EN_RT,

> +	F_INT_CFG_DRDY, F_INT_EN_DRDY, F_IPOL, F_PP_OD,

> +	/* CTRL_REG3 */

> +	F_WRAPTOONE, F_EXTCTRLEN, F_FS_DOUBLE,

> +	/* MAX FIELDS */

> +	F_MAX_FIELDS,

> +};

> +

> +static const struct reg_field fxas2100x_reg_fields[] = {

> +	[F_DR_STATUS]		= REG_FIELD(FXAS2100X_REG_STATUS, 0, 7),

> +	[F_OUT_X_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_X_MSB, 0, 7),

> +	[F_OUT_X_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_X_LSB, 0, 7),

> +	[F_OUT_Y_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_Y_MSB, 0, 7),

> +	[F_OUT_Y_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_Y_LSB, 0, 7),

> +	[F_OUT_Z_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_Z_MSB, 0, 7),

> +	[F_OUT_Z_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_Z_LSB, 0, 7),

> +	[F_ZYX_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 7, 7),

> +	[F_Z_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 6, 6),

> +	[F_Y_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 5, 5),

> +	[F_X_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 4, 4),

> +	[F_ZYX_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 3, 3),

> +	[F_Z_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 2, 2),

> +	[F_Y_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 1, 1),

> +	[F_X_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 0, 0),

> +	[F_OVF]			= REG_FIELD(FXAS2100X_REG_F_STATUS, 7, 7),

> +	[F_WMKF]		= REG_FIELD(FXAS2100X_REG_F_STATUS, 6, 6),

> +	[F_CNT]			= REG_FIELD(FXAS2100X_REG_F_STATUS, 0, 5),

> +	[F_MODE]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 6, 7),

> +	[F_WMRK]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 0, 5),

> +	[F_EVENT]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 5, 5),

> +	[FE_TIME]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 0, 4),

> +	[F_BOOTEND]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 3, 3),

> +	[F_SRC_FIFO]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 2, 2),

> +	[F_SRC_RT]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 1, 1),

> +	[F_SRC_DRDY]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 0, 0),

> +	[F_WHO_AM_I]		= REG_FIELD(FXAS2100X_REG_WHO_AM_I, 0, 7),

> +	[F_BW]			= REG_FIELD(FXAS2100X_REG_CTRL0, 6, 7),

> +	[F_SPIW]		= REG_FIELD(FXAS2100X_REG_CTRL0, 5, 5),

> +	[F_SEL]			= REG_FIELD(FXAS2100X_REG_CTRL0, 3, 4),

> +	[F_HPF_EN]		= REG_FIELD(FXAS2100X_REG_CTRL0, 2, 2),

> +	[F_FS]			= REG_FIELD(FXAS2100X_REG_CTRL0, 0, 1),

> +	[F_ELE]			= REG_FIELD(FXAS2100X_REG_RT_CFG, 3, 3),

> +	[F_ZTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 2, 2),

> +	[F_YTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 1, 1),

> +	[F_XTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 0, 0),

> +	[F_EA]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 6, 6),

> +	[F_ZRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 5, 5),

> +	[F_ZRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 4, 4),

> +	[F_YRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 3, 3),

> +	[F_YRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 2, 2),

> +	[F_XRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 1, 1),

> +	[F_XRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 0, 0),

> +	[F_DBCNTM]		= REG_FIELD(FXAS2100X_REG_RT_THS, 7, 7),

> +	[F_THS]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 0, 6),

> +	[F_RT_COUNT]		= REG_FIELD(FXAS2100X_REG_RT_COUNT, 0, 7),

> +	[F_TEMP]		= REG_FIELD(FXAS2100X_REG_TEMP, 0, 7),

> +	[F_RST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 6, 6),

> +	[F_ST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 5, 5),

> +	[F_DR]			= REG_FIELD(FXAS2100X_REG_CTRL1, 2, 4),

> +	[F_ACTIVE]		= REG_FIELD(FXAS2100X_REG_CTRL1, 1, 1),

> +	[F_READY]		= REG_FIELD(FXAS2100X_REG_CTRL1, 0, 0),

> +	[F_INT_CFG_FIFO]	= REG_FIELD(FXAS2100X_REG_CTRL2, 7, 7),

> +	[F_INT_EN_FIFO]		= REG_FIELD(FXAS2100X_REG_CTRL2, 6, 6),

> +	[F_INT_CFG_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 5, 5),

> +	[F_INT_EN_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 4, 4),

> +	[F_INT_CFG_DRDY]	= REG_FIELD(FXAS2100X_REG_CTRL2, 3, 3),

> +	[F_INT_EN_DRDY]		= REG_FIELD(FXAS2100X_REG_CTRL2, 2, 2),

> +	[F_IPOL]		= REG_FIELD(FXAS2100X_REG_CTRL2, 1, 1),

> +	[F_PP_OD]		= REG_FIELD(FXAS2100X_REG_CTRL2, 0, 0),

> +	[F_WRAPTOONE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 3, 3),

> +	[F_EXTCTRLEN]		= REG_FIELD(FXAS2100X_REG_CTRL3, 2, 2),

> +	[F_FS_DOUBLE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 0, 0),

> +};

> +

> +extern const struct dev_pm_ops fxas2100x_pm_ops;

> +

> +int fxas2100x_core_probe(struct device *dev, struct regmap *regmap, int irq,

> +			 const char *name);

> +void fxas2100x_core_remove(struct device *dev);

> +#endif

> diff --git a/drivers/iio/gyro/fxas2100x_core.c b/drivers/iio/gyro/fxas2100x_core.c

> new file mode 100644

> index 000000000000..9c0ba283fea8

> --- /dev/null

> +++ b/drivers/iio/gyro/fxas2100x_core.c

> @@ -0,0 +1,931 @@

> +// SPDX-License-Identifier: GPL-2.0

> +/*

> + * Driver for NXP FXAS2100x Gyroscope - Core

> + *

> + * Copyright (C) 2019 Linaro Ltd.

> + *

Blank line doesn't add anything...

> + */

> +

> +#include <linux/interrupt.h>

> +#include <linux/module.h>

> +#include <linux/pm.h>

> +#include <linux/pm_runtime.h>

> +#include <linux/regmap.h>

> +#include <linux/regulator/consumer.h>

> +

> +#include <linux/iio/events.h>

> +#include <linux/iio/iio.h>

> +#include <linux/iio/buffer.h>

> +#include <linux/iio/sysfs.h>

> +#include <linux/iio/trigger.h>

> +#include <linux/iio/trigger_consumer.h>

> +#include <linux/iio/triggered_buffer.h>

> +

> +#include "fxas2100x.h"

> +

> +#define FXAS21002_CHIP_ID_1	0xD6

> +#define FXAS21002_CHIP_ID_2	0xD7

> +

> +enum fxas2100x_mode_state {

> +	FXAS2100X_MODE_STANDBY,

> +	FXAS2100X_MODE_READY,

> +	FXAS2100X_MODE_ACTIVE,

> +};

> +

> +#define FXAS2100X_STANDBY_ACTIVE_TIME_MS	62

> +#define FXAS2100X_READY_ACTIVE_TIME_MS		7

> +

> +#define FXAS2100X_ODR_LIST_MAX		10

> +

> +#define FXAS2100X_SCALE_FRACTIONAL	32

> +#define FXAS2100X_RANGE_LIMIT_DOUBLE	2000

> +

> +#define FXAS2100X_AXIS_TO_REG(axis)	(FXAS2100X_REG_OUT_X_MSB + ((axis) * 2))

> +

> +static const int fxas2100x_odr_values[] = {

> +	800, 400, 200, 100, 50, 25, 12, 12

> +};

> +

> +/*

> + * These values are taken from the low-pass filter cutoff frequency calculated

> + * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 0.32

> + * => LPF cutoff frequency = 800 * 0.32 = 256 Hz

> + */

> +static const int fxas2100x_lpf_values[] = {

> +	32, 16, 8

> +};

> +

> +/*

> + * These values are taken from the high-pass filter cutoff frequency calculated

> + * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 0.018750

> + * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz

> + */

> +static const int fxas2100x_hpf_values[] = {

> +	18750, 9625, 4875, 2475

> +};

> +

> +static const int fxas2100x_range_values[] = {

> +	4000, 2000, 1000, 500, 250

> +};

> +

> +struct fxas2100x_data {

> +	u8 chip_id;

> +	enum fxas2100x_mode_state mode;

> +	enum fxas2100x_mode_state prev_mode;

> +

> +	struct mutex lock;		/* serialize data access */

> +	struct regmap *regmap;

> +	struct regmap_field *regmap_fields[F_MAX_FIELDS];

> +	s16 buffer[8];

Given you are doing a bulk read, I think there are paths in regmap
that will result in that being used for dma.

Hence it probably needs to be forced into it's own cacheline.
https://events.linuxfoundation.org/wp-content/uploads/2017/12/20181023-Wolfram-Sang-ELCE18-safe_dma_buffers.pdf
is a good read for this if you haven't seen it.

> +

> +	struct iio_trigger *dready_trig;

> +	int irq;

> +

> +	struct regulator *vdd;

> +	struct regulator *vddio;

> +};

> +

> +enum fxas2100x_channel_index {

> +	CHANNEL_SCAN_INDEX_X,

> +	CHANNEL_SCAN_INDEX_Y,

> +	CHANNEL_SCAN_INDEX_Z,

> +	CHANNEL_SCAN_MAX,

> +};

> +

> +static int fxas2100x_odr_hz_from_value(struct fxas2100x_data *data, u8 value)

> +{

> +	int odr_value_max = ARRAY_SIZE(fxas2100x_odr_values) - 1;

> +

> +	value = min_t(u8, value, odr_value_max);

> +

> +	return fxas2100x_odr_values[value];

> +}

> +

> +static int fxas2100x_odr_value_from_hz(struct fxas2100x_data *data,

> +				       unsigned int hz)

> +{

> +	int odr_table_size = ARRAY_SIZE(fxas2100x_odr_values);

> +	int i;

> +

> +	for (i = 0; i < odr_table_size; i++)

> +		if (fxas2100x_odr_values[i] == hz)

> +			return i;

> +

> +	return -EINVAL;

> +}

> +

> +static int fxas2100x_lpf_bw_from_value(struct fxas2100x_data *data, u8 value)

> +{

> +	int lpf_value_max = ARRAY_SIZE(fxas2100x_lpf_values) - 1;

> +

> +	value = min_t(u8, value, lpf_value_max);

> +

> +	return fxas2100x_lpf_values[value];

> +}

> +

> +static int fxas2100x_lpf_value_from_bw(struct fxas2100x_data *data,

> +				       unsigned int hz)

> +{

> +	int lpf_table_size = ARRAY_SIZE(fxas2100x_lpf_values);

> +	int i;

> +

> +	for (i = 0; i < lpf_table_size; i++)

> +		if (fxas2100x_lpf_values[i] == hz)

> +			return i;

> +

> +	return -EINVAL;

> +}

> +

> +static int fxas2100x_hpf_sel_from_value(struct fxas2100x_data *data, u8 value)

> +{

> +	int hpf_value_max = ARRAY_SIZE(fxas2100x_hpf_values) - 1;

> +

> +	value = min_t(u8, value, hpf_value_max);

> +

> +	return fxas2100x_hpf_values[value];

> +}

> +

> +static int fxas2100x_hpf_value_from_sel(struct fxas2100x_data *data,

> +					unsigned int hz)

> +{

> +	int hpf_table_size = ARRAY_SIZE(fxas2100x_hpf_values);

> +	int i;

> +

> +	for (i = 0; i < hpf_table_size; i++)

> +		if (fxas2100x_hpf_values[i] == hz)

> +			return i;

> +

> +	return -EINVAL;

> +}

> +

> +static int fxas2100x_range_fs_from_value(struct fxas2100x_data *data,

> +					 u8 value)

> +{

> +	int range_value_max = ARRAY_SIZE(fxas2100x_range_values) - 1;

> +	unsigned int fs_double;

> +	int ret;

> +

> +	/* We need to check if FS_DOUBLE is enabled to offset the value */

> +	ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], &fs_double);

> +	if (ret < 0)

> +		return ret;

> +

> +	if (!fs_double)

> +		value += 1;

> +

> +	value = min_t(u8, value, range_value_max);

> +

> +	return fxas2100x_range_values[value];

> +}

> +

> +static int fxas2100x_range_value_from_fs(struct fxas2100x_data *data,

> +					 unsigned int range)

> +{

> +	int range_table_size = ARRAY_SIZE(fxas2100x_range_values);

> +	bool found = false;

> +	int ret;

> +	int i;

> +

> +	for (i = 0; i < range_table_size; i++)

> +		if (fxas2100x_range_values[i] == range)

> +			found = true;

break?
> +	if (!found)

> +		return -EINVAL;

> +

> +	if (range > FXAS2100X_RANGE_LIMIT_DOUBLE)

> +		ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 1);

> +	else

> +		ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 0);

Maybe use a local variable for the 0/1 or a ternary operator.

> +	if (ret < 0)

> +		return ret;

> +

> +	return i;

> +}

> +

> +static int fxas2100x_mode_get(struct fxas2100x_data *data)

> +{

> +	unsigned int active;

> +	unsigned int ready;

> +	int ret;

> +

> +	ret = regmap_field_read(data->regmap_fields[F_ACTIVE], &active);

> +	if (ret < 0)

> +		return ret;

> +	if (active)

> +		return FXAS2100X_MODE_ACTIVE;

> +

> +	ret = regmap_field_read(data->regmap_fields[F_READY], &ready);

> +	if (ret < 0)

> +		return ret;

> +	if (ready)

> +		return FXAS2100X_MODE_READY;

> +

> +	return FXAS2100X_MODE_STANDBY;

> +}

> +

> +static int fxas2100x_mode_set(struct fxas2100x_data *data,

> +			      enum fxas2100x_mode_state mode)

> +{

> +	int ret;

> +

> +	if (mode > FXAS2100X_MODE_ACTIVE)

> +		return -EINVAL;

This seems rather paranoid given the value is coming from this driver...

> +

> +	if (mode == data->mode)

> +		return 0;

> +

> +	if (mode == FXAS2100X_MODE_READY)

> +		ret = regmap_field_write(data->regmap_fields[F_READY], 1);

> +	else

> +		ret = regmap_field_write(data->regmap_fields[F_READY], 0);

> +	if (ret < 0)

> +		return ret;

> +

> +	if (mode == FXAS2100X_MODE_ACTIVE)

> +		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 1);

> +	else

> +		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 0);

> +	if (ret < 0)

> +		return ret;

> +

> +	/* if going to active wait the setup times */

> +	if (mode == FXAS2100X_MODE_ACTIVE)

> +		if (data->mode == FXAS2100X_MODE_STANDBY)

> +			msleep_interruptible(FXAS2100X_STANDBY_ACTIVE_TIME_MS);


Combine the two if statements?

> +	if (data->mode == FXAS2100X_MODE_READY)

> +		msleep_interruptible(FXAS2100X_READY_ACTIVE_TIME_MS);

> +

> +	data->prev_mode = data->mode;

> +	data->mode = mode;

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_write(struct fxas2100x_data *data,

> +			   enum fxas2100x_fields field, int bits)

> +{

> +	int actual_mode;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +

> +	actual_mode = fxas2100x_mode_get(data);

> +	if (actual_mode < 0) {

> +		ret = actual_mode;

> +		goto out_unlock;

> +	}

> +

> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);

> +	if (ret < 0)

> +		goto out_unlock;

> +

> +	ret = regmap_field_write(data->regmap_fields[field], bits);

> +	if (ret < 0)

> +		goto out_unlock;

> +

> +	ret = fxas2100x_mode_set(data, data->prev_mode);

> +

> +out_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int  fxas2100x_pm_get(struct fxas2100x_data *data)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	int ret;

> +

> +	ret = pm_runtime_get_sync(dev);

> +	if (ret < 0)

> +		pm_runtime_put_noidle(dev);

> +

> +	return ret;

> +}

> +

> +static int  fxas2100x_pm_put(struct fxas2100x_data *data)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +

> +	pm_runtime_mark_last_busy(dev);

> +

> +	return pm_runtime_put_autosuspend(dev);

> +}

> +

> +static int fxas2100x_temp_get(struct fxas2100x_data *data, int *val)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	unsigned int temp;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = fxas2100x_pm_get(data);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	ret = regmap_field_read(data->regmap_fields[F_TEMP], &temp);

> +	if (ret < 0) {

> +		dev_err(dev, "failed to read temp: %d\n", ret);

> +		goto data_unlock;

> +	}

> +

> +	*val = sign_extend32(temp, 7);

> +

> +	ret = fxas2100x_pm_put(data);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	ret = IIO_VAL_INT;

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_axis_get(struct fxas2100x_data *data, int index, int *val)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	__be16 axis_be;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = fxas2100x_pm_get(data);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	ret = regmap_bulk_read(data->regmap, FXAS2100X_AXIS_TO_REG(index),

> +			       &axis_be, sizeof(axis_be));

> +	if (ret < 0) {

> +		dev_err(dev, "failed to read axis: %d: %d\n", index, ret);

> +		goto data_unlock;

> +	}

> +

> +	*val = sign_extend32(be16_to_cpu(axis_be), 15);

> +

> +	ret = fxas2100x_pm_put(data);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	ret = IIO_VAL_INT;

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_odr_get(struct fxas2100x_data *data, int *odr)

> +{

> +	unsigned int odr_bits;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	*odr = fxas2100x_odr_hz_from_value(data, odr_bits);

> +

> +	ret = IIO_VAL_INT;

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_odr_set(struct fxas2100x_data *data, int odr)

> +{

> +	int odr_bits;

> +

> +	odr_bits = fxas2100x_odr_value_from_hz(data, odr);

> +	if (odr_bits < 0)

> +		return odr_bits;

> +

> +	return fxas2100x_write(data, F_DR, odr_bits);

> +}

> +

> +static int fxas2100x_lpf_get(struct fxas2100x_data *data, int *val2)

> +{

> +	unsigned int bw_bits;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	*val2 = fxas2100x_lpf_bw_from_value(data, bw_bits) * 10000;

> +

> +	ret = IIO_VAL_INT_PLUS_MICRO;

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_lpf_set(struct fxas2100x_data *data, int bw)

> +{

> +	int bw_bits;

> +	int odr;

> +	int ret;

> +

> +	bw_bits = fxas2100x_lpf_value_from_bw(data, bw);

> +	if (bw_bits < 0)

> +		return bw_bits;

> +

> +	/*

> +	 * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08

> +	 * is not allowed and for ODR = 12.5 value 0.16 is also not allowed

> +	 */

> +	ret = fxas2100x_odr_get(data, &odr);

> +	if (ret < 0)

> +		return -EINVAL;

> +

> +	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))

> +		return -EINVAL;

> +

> +	return fxas2100x_write(data, F_BW, bw_bits);

> +}

> +

> +static int fxas2100x_hpf_get(struct fxas2100x_data *data, int *val2)

> +{

> +	unsigned int sel_bits;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	*val2 = fxas2100x_hpf_sel_from_value(data, sel_bits);

> +

> +	ret = IIO_VAL_INT_PLUS_MICRO;

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_hpf_set(struct fxas2100x_data *data, int sel)

> +{

> +	int sel_bits;

> +

> +	sel_bits = fxas2100x_hpf_value_from_sel(data, sel);

> +	if (sel_bits < 0)

> +		return sel_bits;

> +

> +	return fxas2100x_write(data, F_SEL, sel_bits);

> +}

> +

> +static int fxas2100x_scale_get(struct fxas2100x_data *data, int *val)

> +{

> +	int fs_bits;

> +	int scale;

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);

> +	if (ret < 0)

> +		goto data_unlock;

> +

> +	scale = fxas2100x_range_fs_from_value(data, fs_bits);

> +

> +	*val = scale;

> +

> +	ret = IIO_VAL_FRACTIONAL;

Given this isn't responsible for setting up val2, I would not
return IIO_VAL_FRACTIONAL from here, but rather 0 and handle
the outer return in the caller.  Or set val2 in here...

> +

> +data_unlock:

> +	mutex_unlock(&data->lock);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_scale_set(struct fxas2100x_data *data, int range)

> +{

> +	int fs_bits;

> +

> +	fs_bits = fxas2100x_range_value_from_fs(data, range);

> +	if (fs_bits < 0)

> +		return fs_bits;

> +

> +	return fxas2100x_write(data, F_FS, fs_bits);

> +}

> +

> +static int fxas2100x_read_raw(struct iio_dev *indio_dev,

> +			      struct iio_chan_spec const *chan, int *val,

> +			      int *val2, long mask)

> +{

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +

> +	switch (mask) {

> +	case IIO_CHAN_INFO_RAW:

> +		switch (chan->type) {

> +		case IIO_TEMP:

> +			return fxas2100x_temp_get(data, val);

> +		case IIO_ANGL_VEL:

> +			return fxas2100x_axis_get(data, chan->scan_index, val);

> +		default:

> +			return -EINVAL;

> +		}

> +	case IIO_CHAN_INFO_SCALE:

> +		switch (chan->type) {

> +		case IIO_ANGL_VEL:

> +			*val2 = FXAS2100X_SCALE_FRACTIONAL;

> +			return fxas2100x_scale_get(data, val);

> +		default:

> +			return -EINVAL;

> +		}

> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:

> +		*val = 0;

> +		return fxas2100x_lpf_get(data, val2);

> +	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:

> +		*val = 0;

> +		return fxas2100x_hpf_get(data, val2);

> +	case IIO_CHAN_INFO_SAMP_FREQ:

> +		*val2 = 0;

> +		return fxas2100x_odr_get(data, val);

> +	default:

> +		return -EINVAL;

> +	}

> +}

> +

> +static int fxas2100x_write_raw(struct iio_dev *indio_dev,

> +			       struct iio_chan_spec const *chan, int val,

> +			       int val2, long mask)

> +{

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +	int range;

> +

> +	switch (mask) {

> +	case IIO_CHAN_INFO_SAMP_FREQ:

> +		if (val2)

> +			return -EINVAL;

> +

> +		return fxas2100x_odr_set(data, val);

> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:

> +		if (val)

> +			return -EINVAL;

> +

> +		val2 = val2 / 10000;

> +		return fxas2100x_lpf_set(data, val2);

> +	case IIO_CHAN_INFO_SCALE:

> +		switch (chan->type) {

> +		case IIO_ANGL_VEL:

> +			range = (((val * 1000 + val2 / 1000) *

> +				  FXAS2100X_SCALE_FRACTIONAL) / 1000);

> +			return fxas2100x_scale_set(data, range);

> +		default:

> +			return -EINVAL;

> +		}

> +	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:

> +		return fxas2100x_hpf_set(data, val2);

> +	default:

> +		return -EINVAL;

> +	}

> +}

> +

> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");

> +

> +static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,

> +		      "0.32 0.16 0.08");

> +

> +static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,

> +		      "0.018750 0.009625 0.004875 0.002475");

> +

> +static IIO_CONST_ATTR(in_anglvel_scale_available,

> +		      "125.0 62.5 31.25 15.625 7.8125");

> +

> +static struct attribute *fxas2100x_attributes[] = {

> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,

> +	&iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,

> +	&iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,

> +	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,

> +	NULL,

> +};

> +

> +static const struct attribute_group fxas2100x_attrs_group = {

> +	.attrs = fxas2100x_attributes,

> +};

> +

> +#define FXAS2100X_CHANNEL(_axis) {					\

> +	.type = IIO_ANGL_VEL,						\

> +	.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) |	\

> +		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\

> +	.scan_index = CHANNEL_SCAN_INDEX_##_axis,			\

> +	.scan_type = {							\

> +		.sign = 's',						\

> +		.realbits = 16,						\

> +		.storagebits = 16,					\

> +		.endianness = IIO_BE,					\

> +	},								\

> +}

> +

> +static const struct iio_chan_spec fxas2100x_channels[] = {

> +	{

> +		.type = IIO_TEMP,

> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

> +		.scan_index = -1,

> +	},

> +	FXAS2100X_CHANNEL(X),

> +	FXAS2100X_CHANNEL(Y),

> +	FXAS2100X_CHANNEL(Z),

> +};

> +

> +static const struct iio_info fxas2100x_info = {

> +	.attrs			= &fxas2100x_attrs_group,

> +	.read_raw		= &fxas2100x_read_raw,

> +	.write_raw		= &fxas2100x_write_raw,

> +};

> +

> +static irqreturn_t fxas2100x_trigger_handler(int irq, void *p)

> +{

> +	struct iio_poll_func *pf = p;

> +	struct iio_dev *indio_dev = pf->indio_dev;

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +	int ret;

> +

> +	mutex_lock(&data->lock);

> +	ret = regmap_bulk_read(data->regmap, FXAS2100X_REG_OUT_X_MSB,

> +			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));

> +	mutex_unlock(&data->lock);

> +	if (ret < 0)

> +		goto notify_done;

> +

> +	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,

> +					   pf->timestamp);

> +

> +notify_done:

> +	iio_trigger_notify_done(indio_dev->trig);

> +

> +	return IRQ_HANDLED;

> +}

> +

> +static int fxas2100x_chip_init(struct fxas2100x_data *data)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	unsigned int chip_id;

> +	int ret;

> +

> +	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);

> +	if (ret < 0)

> +		return ret;

> +

> +	if (chip_id != FXAS21002_CHIP_ID_1 && chip_id != FXAS21002_CHIP_ID_2) {

> +		dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);

> +		return -EINVAL;

> +	}

> +

> +	data->chip_id = chip_id;

> +

> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);

> +	if (ret < 0)

> +		return ret;

> +

> +	/* Set ODR to 200HZ as default */

> +	ret = fxas2100x_odr_set(data, 200);

> +	if (ret < 0)

> +		dev_err(dev, "failed to set ODR: %d\n", ret);

> +

> +	return ret;

> +}

> +

> +static int fxas2100x_data_rdy_trigger_set_state(struct iio_trigger *trig,

> +						bool state)

> +{

> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +

> +	return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);

> +}

> +

> +static const struct iio_trigger_ops fxas2100x_trigger_ops = {

> +	.set_trigger_state = &fxas2100x_data_rdy_trigger_set_state,

> +};

> +

> +static irqreturn_t fxas2100x_data_rdy_trig_poll(int irq, void *private)

> +{

> +	struct iio_dev *indio_dev = private;

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +

> +	iio_trigger_poll(data->dready_trig);

> +

> +	return IRQ_HANDLED;

> +}

> +

> +static int fxas2100x_trigger_probe(struct fxas2100x_data *data)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	int ret;

> +

> +	if (!data->irq)

> +		return 0;

> +

> +	data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",

> +						   indio_dev->name,

> +						   indio_dev->id);

> +	if (!data->dready_trig)

> +		return -ENOMEM;

> +

> +	ret = devm_request_irq(dev, data->irq, fxas2100x_data_rdy_trig_poll,

> +			       IRQF_TRIGGER_RISING, "fxas2100x_data_ready",

> +			       data->dready_trig);

> +	if (ret < 0)

> +		return ret;

> +

> +	data->dready_trig->dev.parent = dev;

> +	data->dready_trig->ops = &fxas2100x_trigger_ops;

> +	iio_trigger_set_drvdata(data->dready_trig, indio_dev);

> +

> +	return devm_iio_trigger_register(dev, data->dready_trig);

> +}

> +

> +static int fxas2100x_power_enable(struct fxas2100x_data *data)

> +{

> +	struct device *dev = regmap_get_device(data->regmap);

> +	int ret;

> +

> +	data->vdd = devm_regulator_get(dev->parent, "vdd");

> +	if (IS_ERR(data->vdd)) {

> +		dev_err(dev, "failed to get Vdd supply\n");

> +		return PTR_ERR(data->vdd);

> +	}

> +

> +	ret = regulator_enable(data->vdd);

> +	if (ret < 0)

> +		return ret;

> +

> +	data->vddio = devm_regulator_get(dev->parent, "vddio");

> +	if (IS_ERR(data->vddio)) {

> +		dev_err(dev, "failed to get Vdd_IO supply\n");

This is rather noisy. Might simply be a deferred result if
the regulator driver hasn't loaded yet...

> +		regulator_disable(data->vdd);

> +		return PTR_ERR(data->vddio);

> +	}

> +

> +	ret = regulator_enable(data->vddio);

> +	if (ret < 0)

If this fails, should be turning off the earlier regulator.
I would suggest a goto and one place to handle all error paths
where cleanup is needed.

As mentioned below, consider devm_add_action_or_reset to
automatically handle the regulator disables.

> +		return ret;

> +

> +	return 0;

> +}

> +

> +static void fxas2100x_power_disable(struct fxas2100x_data *data)

> +{

> +	regulator_disable(data->vdd);

> +	regulator_disable(data->vddio);

> +}

> +

> +int fxas2100x_core_probe(struct device *dev, struct regmap *regmap, int irq,

> +			 const char *name)

> +{

> +	struct fxas2100x_data *data;

> +	struct iio_dev *indio_dev;

> +	struct regmap_field *f;

> +	int i;

> +	int ret;

> +

> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));

> +	if (!indio_dev)

> +		return -ENOMEM;

> +

> +	data = iio_priv(indio_dev);

> +	dev_set_drvdata(dev, indio_dev);

> +	data->irq = irq;

> +	data->regmap = regmap;

> +

> +	for (i = 0; i < F_MAX_FIELDS; i++) {

> +		f = devm_regmap_field_alloc(dev, data->regmap,

> +					    fxas2100x_reg_fields[i]);

> +		if (IS_ERR(f))

> +			return PTR_ERR(f);

> +

> +		data->regmap_fields[i] = f;

> +	}

> +

> +	mutex_init(&data->lock);

> +

> +	ret = fxas2100x_power_enable(data);

> +	if (ret < 0)

> +		return ret;

> +

> +	ret = fxas2100x_chip_init(data);

> +	if (ret < 0)

> +		goto power_disable;

> +

> +	indio_dev->dev.parent = dev;

> +	indio_dev->channels = fxas2100x_channels;

> +	indio_dev->num_channels = ARRAY_SIZE(fxas2100x_channels);

> +	indio_dev->name = name;

> +	indio_dev->modes = INDIO_DIRECT_MODE;

> +	indio_dev->info = &fxas2100x_info;

> +

> +	ret = fxas2100x_trigger_probe(data);

> +	if (ret < 0)

> +		goto power_disable;

> +

> +	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,

> +					      iio_pollfunc_store_time,

> +					      fxas2100x_trigger_handler, NULL);

> +	if (ret < 0)


This results in the unwind ordering being different from the setup.
If you want to use devm_ functions after the regulators are enabled,
look at devm_add_action_or_reset to automatically disable the regulators
and maintain the ordering.

Whilst this probably doesn't lead to any bugs, having different ordering
in probe and remove makes review harder + often ends up with bugs
being introduced by later changes to the driver.

> +		goto power_disable;

> +

> +	ret = pm_runtime_set_active(dev);

> +	if (ret)

> +		goto power_disable;

> +

> +	pm_runtime_enable(dev);

> +	pm_runtime_set_autosuspend_delay(dev, 2000);

> +	pm_runtime_use_autosuspend(dev);

> +

> +	ret = devm_iio_device_register(dev, indio_dev);

> +	if (ret < 0)

> +		goto power_disable;

> +

> +	return 0;

> +

> +power_disable:

> +	fxas2100x_power_disable(data);

> +

> +	return ret;

> +}

> +EXPORT_SYMBOL_GPL(fxas2100x_core_probe);

> +

> +void fxas2100x_core_remove(struct device *dev)

> +{

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +

> +	pm_runtime_disable(dev);

> +	pm_runtime_set_suspended(dev);

> +	pm_runtime_put_noidle(dev);

> +

> +	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);

> +	fxas2100x_power_disable(data);

> +}

> +EXPORT_SYMBOL_GPL(fxas2100x_core_remove);

> +

> +static int __maybe_unused fxas2100x_suspend(struct device *dev)

> +{

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

	struct fxas2100x_data *data = iio_priv(dev_get_drvdata(dev));

Doesn't loose any meaning and is more compact. (really minor comment
though).

> +

> +	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);


Might be worth considering disabling the regulators.

> +

> +	return 0;

> +}

> +

> +static int __maybe_unused fxas2100x_resume(struct device *dev)

> +{

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +

> +	fxas2100x_mode_set(data, data->prev_mode);

Error handling?  Might not be possible do do anything useful but
good to know there was an error.

> +

> +	return 0;

> +}

> +

> +static int __maybe_unused fxas2100x_runtime_suspend(struct device *dev)

> +{

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +	int ret;

> +

> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);

> +	if (ret < 0)

> +		return -EAGAIN;

> +

> +	return 0;

> +}

> +

> +static int __maybe_unused fxas2100x_runtime_resume(struct device *dev)

> +{

> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> +	int ret;

> +

> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_ACTIVE);

> +	if (ret < 0)

> +		return -EAGAIN;


That seems unusual.  Why does EAGAIN make sense?

> +

> +	return 0;

> +}

> +

> +const struct dev_pm_ops fxas2100x_pm_ops = {

> +	SET_SYSTEM_SLEEP_PM_OPS(fxas2100x_suspend, fxas2100x_resume)

> +	SET_RUNTIME_PM_OPS(fxas2100x_runtime_suspend,

> +			   fxas2100x_runtime_resume, NULL)

> +};

> +EXPORT_SYMBOL_GPL(fxas2100x_pm_ops);

> +

> +MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");

> +MODULE_LICENSE("GPL v2");

> +MODULE_DESCRIPTION("FXAS2100X Gyro driver");
Rui Miguel Silva Feb. 7, 2019, 3:32 p.m. | #2
Hi Jonathan,
On Wed 06 Feb 2019 at 13:18, Jonathan Cameron wrote:
> On Tue, 5 Feb 2019 17:43:30 +0000

> Rui Miguel Silva <rui.silva@linaro.org> wrote:

>

>> This adds core support for the NXP fxas2100x Tri-axis 

>> gyroscope, using

>> the iio subsystem. It supports PM operations, axis reading, 

>> temperature, scale

>> factor of the axis, high pass and low pass filtering, and 

>> sampling frequency

>> selection.

>> 

>> It will have extras modules to support the communication over 

>> i2c

>> and spi.

>> 

>> Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>

> One quick general comment. 

>

> Please don't use wildcards in driver names. It goes wrong far to 

> often.

> The convention is pick a part that is supported (usually the 

> first one)

> and name it after that.

>

> Some quick review comments inline.  I'll take a closer look at 

> v3 but won't

> get back to this until at least the weekend.


Thanks for your reviews, I will take them in account in v3. I'll
maybe have some time next week to send.

---
Cheers,
	Rui

>

> Jonathan

>

>> ---

>>  drivers/iio/gyro/Kconfig          |  11 +

>>  drivers/iio/gyro/Makefile         |   1 +

>>  drivers/iio/gyro/fxas2100x.h      | 151 +++++

>>  drivers/iio/gyro/fxas2100x_core.c | 931 

>>  ++++++++++++++++++++++++++++++

>>  4 files changed, 1094 insertions(+)

>>  create mode 100644 drivers/iio/gyro/fxas2100x.h

>>  create mode 100644 drivers/iio/gyro/fxas2100x_core.c

>> 

>> diff --git a/drivers/iio/gyro/Kconfig 

>> b/drivers/iio/gyro/Kconfig

>> index 3126cf05e6b9..c168aa63de3b 100644

>> --- a/drivers/iio/gyro/Kconfig

>> +++ b/drivers/iio/gyro/Kconfig

>> @@ -73,6 +73,17 @@ config BMG160_SPI

>>  	tristate

>>  	select REGMAP_SPI

>>  

>> +config FXAS2100X

>> +	tristate "NXP FXAS2100X Gyro Sensor"

>> +	select IIO_BUFFER

>> +	select IIO_TRIGGERED_BUFFER

>> +	help

>> +	  Say yes here to build support for NXP FXAS2100X family 

>> Tri-axis Gyro

>> +	  Sensor driver connected via I2C or SPI.

>> +

>> +	  This driver can also be built as a module.  If so, the 

>> module

>> +	  will be called fxas2100x_i2c or fxas2100x_spi.

>> +

>>  config HID_SENSOR_GYRO_3D

>>  	depends on HID_SENSOR_HUB

>>  	select IIO_BUFFER

>> diff --git a/drivers/iio/gyro/Makefile 

>> b/drivers/iio/gyro/Makefile

>> index 295ec780c4eb..9e2395185a6e 100644

>> --- a/drivers/iio/gyro/Makefile

>> +++ b/drivers/iio/gyro/Makefile

>> @@ -12,6 +12,7 @@ obj-$(CONFIG_ADXRS450) += adxrs450.o

>>  obj-$(CONFIG_BMG160) += bmg160_core.o

>>  obj-$(CONFIG_BMG160_I2C) += bmg160_i2c.o

>>  obj-$(CONFIG_BMG160_SPI) += bmg160_spi.o

>> +obj-$(CONFIG_FXAS2100X) += fxas2100x_core.o

>>  

>>  obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o

>>  

>> diff --git a/drivers/iio/gyro/fxas2100x.h 

>> b/drivers/iio/gyro/fxas2100x.h

>> new file mode 100644

>> index 000000000000..2b503196337f

>> --- /dev/null

>> +++ b/drivers/iio/gyro/fxas2100x.h

>> @@ -0,0 +1,151 @@

>> +/* SPDX-License-Identifier: GPL-2.0 */

>> +/*

>> + * Driver for NXP FXAS2100x Gyroscope - Header

>> + *

>> + * Copyright (C) 2019 Linaro Ltd.

>> + *

>> + */

>> +

>> +#ifndef FXAS2100X_H_

>> +#define FXAS2100X_H_

>> +

>> +#include <linux/regmap.h>

>> +

>> +#define FXAS2100X_REG_STATUS		0x00

>> +#define FXAS2100X_REG_OUT_X_MSB		0x01

>> +#define FXAS2100X_REG_OUT_X_LSB		0x02

>> +#define FXAS2100X_REG_OUT_Y_MSB		0x03

>> +#define FXAS2100X_REG_OUT_Y_LSB		0x04

>> +#define FXAS2100X_REG_OUT_Z_MSB		0x05

>> +#define FXAS2100X_REG_OUT_Z_LSB		0x06

>> +#define FXAS2100X_REG_DR_STATUS		0x07

>> +#define FXAS2100X_REG_F_STATUS		0x08

>> +#define FXAS2100X_REG_F_SETUP		0x09

>> +#define FXAS2100X_REG_F_EVENT		0x0A

>> +#define FXAS2100X_REG_INT_SRC_FLAG	0x0B

>> +#define FXAS2100X_REG_WHO_AM_I		0x0C

>> +#define FXAS2100X_REG_CTRL0		0x0D

>> +#define FXAS2100X_REG_RT_CFG		0x0E

>> +#define FXAS2100X_REG_RT_SRC		0x0F

>> +#define FXAS2100X_REG_RT_THS		0x10

>> +#define FXAS2100X_REG_RT_COUNT		0x11

>> +#define FXAS2100X_REG_TEMP		0x12

>> +#define FXAS2100X_REG_CTRL1		0x13

>> +#define FXAS2100X_REG_CTRL2		0x14

>> +#define FXAS2100X_REG_CTRL3		0x15

>> +

>> +enum fxas2100x_fields {

>> +	F_DR_STATUS,

>> +	F_OUT_X_MSB,

>> +	F_OUT_X_LSB,

>> +	F_OUT_Y_MSB,

>> +	F_OUT_Y_LSB,

>> +	F_OUT_Z_MSB,

>> +	F_OUT_Z_LSB,

>> +	/* DR_STATUS */

>> +	F_ZYX_OW, F_Z_OW, F_Y_OW, F_X_OW, F_ZYX_DR, F_Z_DR, 

>> F_Y_DR, F_X_DR,

>> +	/* F_STATUS */

>> +	F_OVF, F_WMKF, F_CNT,

>> +	/* F_SETUP */

>> +	F_MODE, F_WMRK,

>> +	/* F_EVENT */

>> +	F_EVENT, FE_TIME,

>> +	/* INT_SOURCE_FLAG */

>> +	F_BOOTEND, F_SRC_FIFO, F_SRC_RT, F_SRC_DRDY,

>> +	/* WHO_AM_I */

>> +	F_WHO_AM_I,

>> +	/* CTRL_REG0 */

>> +	F_BW, F_SPIW, F_SEL, F_HPF_EN, F_FS,

>> +	/* RT_CFG */

>> +	F_ELE, F_ZTEFE, F_YTEFE, F_XTEFE,

>> +	/* RT_SRC */

>> +	F_EA, F_ZRT, F_ZRT_POL, F_YRT, F_YRT_POL, F_XRT, 

>> F_XRT_POL,

>> +	/* RT_THS */

>> +	F_DBCNTM, F_THS,

>> +	/* RT_COUNT */

>> +	F_RT_COUNT,

>> +	/* TEMP */

>> +	F_TEMP,

>> +	/* CTRL_REG1 */

>> +	F_RST, F_ST, F_DR, F_ACTIVE, F_READY,

>> +	/* CTRL_REG2 */

>> +	F_INT_CFG_FIFO, F_INT_EN_FIFO, F_INT_CFG_RT, F_INT_EN_RT,

>> +	F_INT_CFG_DRDY, F_INT_EN_DRDY, F_IPOL, F_PP_OD,

>> +	/* CTRL_REG3 */

>> +	F_WRAPTOONE, F_EXTCTRLEN, F_FS_DOUBLE,

>> +	/* MAX FIELDS */

>> +	F_MAX_FIELDS,

>> +};

>> +

>> +static const struct reg_field fxas2100x_reg_fields[] = {

>> +	[F_DR_STATUS]		= REG_FIELD(FXAS2100X_REG_STATUS, 

>> 0, 7),

>> +	[F_OUT_X_MSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_X_MSB, 0, 7),

>> +	[F_OUT_X_LSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_X_LSB, 0, 7),

>> +	[F_OUT_Y_MSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_Y_MSB, 0, 7),

>> +	[F_OUT_Y_LSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_Y_LSB, 0, 7),

>> +	[F_OUT_Z_MSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_Z_MSB, 0, 7),

>> +	[F_OUT_Z_LSB]		= 

>> REG_FIELD(FXAS2100X_REG_OUT_Z_LSB, 0, 7),

>> +	[F_ZYX_OW]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 7, 7),

>> +	[F_Z_OW]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 6, 6),

>> +	[F_Y_OW]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 5, 5),

>> +	[F_X_OW]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 4, 4),

>> +	[F_ZYX_DR]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 3, 3),

>> +	[F_Z_DR]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 2, 2),

>> +	[F_Y_DR]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 1, 1),

>> +	[F_X_DR]		= 

>> REG_FIELD(FXAS2100X_REG_DR_STATUS, 0, 0),

>> +	[F_OVF]			= 

>> REG_FIELD(FXAS2100X_REG_F_STATUS, 7, 7),

>> +	[F_WMKF]		= 

>> REG_FIELD(FXAS2100X_REG_F_STATUS, 6, 6),

>> +	[F_CNT]			= 

>> REG_FIELD(FXAS2100X_REG_F_STATUS, 0, 5),

>> +	[F_MODE]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 

>> 6, 7),

>> +	[F_WMRK]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 

>> 0, 5),

>> +	[F_EVENT]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 

>> 5, 5),

>> +	[FE_TIME]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 

>> 0, 4),

>> +	[F_BOOTEND]		= 

>> REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 3, 3),

>> +	[F_SRC_FIFO]		= 

>> REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 2, 2),

>> +	[F_SRC_RT]		= 

>> REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 1, 1),

>> +	[F_SRC_DRDY]		= 

>> REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 0, 0),

>> +	[F_WHO_AM_I]		= 

>> REG_FIELD(FXAS2100X_REG_WHO_AM_I, 0, 7),

>> +	[F_BW]			= REG_FIELD(FXAS2100X_REG_CTRL0, 

>> 6, 7),

>> +	[F_SPIW]		= REG_FIELD(FXAS2100X_REG_CTRL0, 

>> 5, 5),

>> +	[F_SEL]			= REG_FIELD(FXAS2100X_REG_CTRL0, 

>> 3, 4),

>> +	[F_HPF_EN]		= REG_FIELD(FXAS2100X_REG_CTRL0, 

>> 2, 2),

>> +	[F_FS]			= REG_FIELD(FXAS2100X_REG_CTRL0, 

>> 0, 1),

>> +	[F_ELE]			= REG_FIELD(FXAS2100X_REG_RT_CFG, 

>> 3, 3),

>> +	[F_ZTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 

>> 2, 2),

>> +	[F_YTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 

>> 1, 1),

>> +	[F_XTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 

>> 0, 0),

>> +	[F_EA]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 6, 6),

>> +	[F_ZRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 5, 5),

>> +	[F_ZRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 4, 4),

>> +	[F_YRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 3, 3),

>> +	[F_YRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 2, 2),

>> +	[F_XRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 1, 1),

>> +	[F_XRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 0, 0),

>> +	[F_DBCNTM]		= REG_FIELD(FXAS2100X_REG_RT_THS, 

>> 7, 7),

>> +	[F_THS]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 

>> 0, 6),

>> +	[F_RT_COUNT]		= 

>> REG_FIELD(FXAS2100X_REG_RT_COUNT, 0, 7),

>> +	[F_TEMP]		= REG_FIELD(FXAS2100X_REG_TEMP, 0, 

>> 7),

>> +	[F_RST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 

>> 6, 6),

>> +	[F_ST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 

>> 5, 5),

>> +	[F_DR]			= REG_FIELD(FXAS2100X_REG_CTRL1, 

>> 2, 4),

>> +	[F_ACTIVE]		= REG_FIELD(FXAS2100X_REG_CTRL1, 

>> 1, 1),

>> +	[F_READY]		= REG_FIELD(FXAS2100X_REG_CTRL1, 

>> 0, 0),

>> +	[F_INT_CFG_FIFO]	= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 7, 7),

>> +	[F_INT_EN_FIFO]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 6, 6),

>> +	[F_INT_CFG_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 5, 5),

>> +	[F_INT_EN_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 4, 4),

>> +	[F_INT_CFG_DRDY]	= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 3, 3),

>> +	[F_INT_EN_DRDY]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 2, 2),

>> +	[F_IPOL]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 1, 1),

>> +	[F_PP_OD]		= REG_FIELD(FXAS2100X_REG_CTRL2, 

>> 0, 0),

>> +	[F_WRAPTOONE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 

>> 3, 3),

>> +	[F_EXTCTRLEN]		= REG_FIELD(FXAS2100X_REG_CTRL3, 

>> 2, 2),

>> +	[F_FS_DOUBLE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 

>> 0, 0),

>> +};

>> +

>> +extern const struct dev_pm_ops fxas2100x_pm_ops;

>> +

>> +int fxas2100x_core_probe(struct device *dev, struct regmap 

>> *regmap, int irq,

>> +			 const char *name);

>> +void fxas2100x_core_remove(struct device *dev);

>> +#endif

>> diff --git a/drivers/iio/gyro/fxas2100x_core.c 

>> b/drivers/iio/gyro/fxas2100x_core.c

>> new file mode 100644

>> index 000000000000..9c0ba283fea8

>> --- /dev/null

>> +++ b/drivers/iio/gyro/fxas2100x_core.c

>> @@ -0,0 +1,931 @@

>> +// SPDX-License-Identifier: GPL-2.0

>> +/*

>> + * Driver for NXP FXAS2100x Gyroscope - Core

>> + *

>> + * Copyright (C) 2019 Linaro Ltd.

>> + *

> Blank line doesn't add anything...

>

>> + */

>> +

>> +#include <linux/interrupt.h>

>> +#include <linux/module.h>

>> +#include <linux/pm.h>

>> +#include <linux/pm_runtime.h>

>> +#include <linux/regmap.h>

>> +#include <linux/regulator/consumer.h>

>> +

>> +#include <linux/iio/events.h>

>> +#include <linux/iio/iio.h>

>> +#include <linux/iio/buffer.h>

>> +#include <linux/iio/sysfs.h>

>> +#include <linux/iio/trigger.h>

>> +#include <linux/iio/trigger_consumer.h>

>> +#include <linux/iio/triggered_buffer.h>

>> +

>> +#include "fxas2100x.h"

>> +

>> +#define FXAS21002_CHIP_ID_1	0xD6

>> +#define FXAS21002_CHIP_ID_2	0xD7

>> +

>> +enum fxas2100x_mode_state {

>> +	FXAS2100X_MODE_STANDBY,

>> +	FXAS2100X_MODE_READY,

>> +	FXAS2100X_MODE_ACTIVE,

>> +};

>> +

>> +#define FXAS2100X_STANDBY_ACTIVE_TIME_MS	62

>> +#define FXAS2100X_READY_ACTIVE_TIME_MS		7

>> +

>> +#define FXAS2100X_ODR_LIST_MAX		10

>> +

>> +#define FXAS2100X_SCALE_FRACTIONAL	32

>> +#define FXAS2100X_RANGE_LIMIT_DOUBLE	2000

>> +

>> +#define FXAS2100X_AXIS_TO_REG(axis)	(FXAS2100X_REG_OUT_X_MSB + 

>> ((axis) * 2))

>> +

>> +static const int fxas2100x_odr_values[] = {

>> +	800, 400, 200, 100, 50, 25, 12, 12

>> +};

>> +

>> +/*

>> + * These values are taken from the low-pass filter cutoff 

>> frequency calculated

>> + * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 

>> 0.32

>> + * => LPF cutoff frequency = 800 * 0.32 = 256 Hz

>> + */

>> +static const int fxas2100x_lpf_values[] = {

>> +	32, 16, 8

>> +};

>> +

>> +/*

>> + * These values are taken from the high-pass filter cutoff 

>> frequency calculated

>> + * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 

>> 0.018750

>> + * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz

>> + */

>> +static const int fxas2100x_hpf_values[] = {

>> +	18750, 9625, 4875, 2475

>> +};

>> +

>> +static const int fxas2100x_range_values[] = {

>> +	4000, 2000, 1000, 500, 250

>> +};

>> +

>> +struct fxas2100x_data {

>> +	u8 chip_id;

>> +	enum fxas2100x_mode_state mode;

>> +	enum fxas2100x_mode_state prev_mode;

>> +

>> +	struct mutex lock;		/* serialize data access 

>> */

>> +	struct regmap *regmap;

>> +	struct regmap_field *regmap_fields[F_MAX_FIELDS];

>> +	s16 buffer[8];

> Given you are doing a bulk read, I think there are paths in 

> regmap

> that will result in that being used for dma.

>

> Hence it probably needs to be forced into it's own cacheline.

> https://events.linuxfoundation.org/wp-content/uploads/2017/12/20181023-Wolfram-Sang-ELCE18-safe_dma_buffers.pdf

> is a good read for this if you haven't seen it.

>

>> +

>> +	struct iio_trigger *dready_trig;

>> +	int irq;

>> +

>> +	struct regulator *vdd;

>> +	struct regulator *vddio;

>> +};

>> +

>> +enum fxas2100x_channel_index {

>> +	CHANNEL_SCAN_INDEX_X,

>> +	CHANNEL_SCAN_INDEX_Y,

>> +	CHANNEL_SCAN_INDEX_Z,

>> +	CHANNEL_SCAN_MAX,

>> +};

>> +

>> +static int fxas2100x_odr_hz_from_value(struct fxas2100x_data 

>> *data, u8 value)

>> +{

>> +	int odr_value_max = ARRAY_SIZE(fxas2100x_odr_values) - 1;

>> +

>> +	value = min_t(u8, value, odr_value_max);

>> +

>> +	return fxas2100x_odr_values[value];

>> +}

>> +

>> +static int fxas2100x_odr_value_from_hz(struct fxas2100x_data 

>> *data,

>> +				       unsigned int hz)

>> +{

>> +	int odr_table_size = ARRAY_SIZE(fxas2100x_odr_values);

>> +	int i;

>> +

>> +	for (i = 0; i < odr_table_size; i++)

>> +		if (fxas2100x_odr_values[i] == hz)

>> +			return i;

>> +

>> +	return -EINVAL;

>> +}

>> +

>> +static int fxas2100x_lpf_bw_from_value(struct fxas2100x_data 

>> *data, u8 value)

>> +{

>> +	int lpf_value_max = ARRAY_SIZE(fxas2100x_lpf_values) - 1;

>> +

>> +	value = min_t(u8, value, lpf_value_max);

>> +

>> +	return fxas2100x_lpf_values[value];

>> +}

>> +

>> +static int fxas2100x_lpf_value_from_bw(struct fxas2100x_data 

>> *data,

>> +				       unsigned int hz)

>> +{

>> +	int lpf_table_size = ARRAY_SIZE(fxas2100x_lpf_values);

>> +	int i;

>> +

>> +	for (i = 0; i < lpf_table_size; i++)

>> +		if (fxas2100x_lpf_values[i] == hz)

>> +			return i;

>> +

>> +	return -EINVAL;

>> +}

>> +

>> +static int fxas2100x_hpf_sel_from_value(struct fxas2100x_data 

>> *data, u8 value)

>> +{

>> +	int hpf_value_max = ARRAY_SIZE(fxas2100x_hpf_values) - 1;

>> +

>> +	value = min_t(u8, value, hpf_value_max);

>> +

>> +	return fxas2100x_hpf_values[value];

>> +}

>> +

>> +static int fxas2100x_hpf_value_from_sel(struct fxas2100x_data 

>> *data,

>> +					unsigned int hz)

>> +{

>> +	int hpf_table_size = ARRAY_SIZE(fxas2100x_hpf_values);

>> +	int i;

>> +

>> +	for (i = 0; i < hpf_table_size; i++)

>> +		if (fxas2100x_hpf_values[i] == hz)

>> +			return i;

>> +

>> +	return -EINVAL;

>> +}

>> +

>> +static int fxas2100x_range_fs_from_value(struct fxas2100x_data 

>> *data,

>> +					 u8 value)

>> +{

>> +	int range_value_max = ARRAY_SIZE(fxas2100x_range_values) - 

>> 1;

>> +	unsigned int fs_double;

>> +	int ret;

>> +

>> +	/* We need to check if FS_DOUBLE is enabled to offset the 

>> value */

>> +	ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], 

>> &fs_double);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	if (!fs_double)

>> +		value += 1;

>> +

>> +	value = min_t(u8, value, range_value_max);

>> +

>> +	return fxas2100x_range_values[value];

>> +}

>> +

>> +static int fxas2100x_range_value_from_fs(struct fxas2100x_data 

>> *data,

>> +					 unsigned int range)

>> +{

>> +	int range_table_size = ARRAY_SIZE(fxas2100x_range_values);

>> +	bool found = false;

>> +	int ret;

>> +	int i;

>> +

>> +	for (i = 0; i < range_table_size; i++)

>> +		if (fxas2100x_range_values[i] == range)

>> +			found = true;

> break?

>> +	if (!found)

>> +		return -EINVAL;

>> +

>> +	if (range > FXAS2100X_RANGE_LIMIT_DOUBLE)

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 1);

>> +	else

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 0);

> Maybe use a local variable for the 0/1 or a ternary operator.

>

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	return i;

>> +}

>> +

>> +static int fxas2100x_mode_get(struct fxas2100x_data *data)

>> +{

>> +	unsigned int active;

>> +	unsigned int ready;

>> +	int ret;

>> +

>> +	ret = regmap_field_read(data->regmap_fields[F_ACTIVE], 

>> &active);

>> +	if (ret < 0)

>> +		return ret;

>> +	if (active)

>> +		return FXAS2100X_MODE_ACTIVE;

>> +

>> +	ret = regmap_field_read(data->regmap_fields[F_READY], 

>> &ready);

>> +	if (ret < 0)

>> +		return ret;

>> +	if (ready)

>> +		return FXAS2100X_MODE_READY;

>> +

>> +	return FXAS2100X_MODE_STANDBY;

>> +}

>> +

>> +static int fxas2100x_mode_set(struct fxas2100x_data *data,

>> +			      enum fxas2100x_mode_state mode)

>> +{

>> +	int ret;

>> +

>> +	if (mode > FXAS2100X_MODE_ACTIVE)

>> +		return -EINVAL;

> This seems rather paranoid given the value is coming from this 

> driver...

>

>> +

>> +	if (mode == data->mode)

>> +		return 0;

>> +

>> +	if (mode == FXAS2100X_MODE_READY)

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_READY], 1);

>> +	else

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_READY], 0);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	if (mode == FXAS2100X_MODE_ACTIVE)

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_ACTIVE], 1);

>> +	else

>> +		ret = 

>> regmap_field_write(data->regmap_fields[F_ACTIVE], 0);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	/* if going to active wait the setup times */

>> +	if (mode == FXAS2100X_MODE_ACTIVE)

>> +		if (data->mode == FXAS2100X_MODE_STANDBY)

>> + 

>> msleep_interruptible(FXAS2100X_STANDBY_ACTIVE_TIME_MS);

>

> Combine the two if statements?

>

>> +	if (data->mode == FXAS2100X_MODE_READY)

>> + 

>> msleep_interruptible(FXAS2100X_READY_ACTIVE_TIME_MS);

>> +

>> +	data->prev_mode = data->mode;

>> +	data->mode = mode;

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_write(struct fxas2100x_data *data,

>> +			   enum fxas2100x_fields field, int bits)

>> +{

>> +	int actual_mode;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +

>> +	actual_mode = fxas2100x_mode_get(data);

>> +	if (actual_mode < 0) {

>> +		ret = actual_mode;

>> +		goto out_unlock;

>> +	}

>> +

>> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);

>> +	if (ret < 0)

>> +		goto out_unlock;

>> +

>> +	ret = regmap_field_write(data->regmap_fields[field], 

>> bits);

>> +	if (ret < 0)

>> +		goto out_unlock;

>> +

>> +	ret = fxas2100x_mode_set(data, data->prev_mode);

>> +

>> +out_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int  fxas2100x_pm_get(struct fxas2100x_data *data)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	int ret;

>> +

>> +	ret = pm_runtime_get_sync(dev);

>> +	if (ret < 0)

>> +		pm_runtime_put_noidle(dev);

>> +

>> +	return ret;

>> +}

>> +

>> +static int  fxas2100x_pm_put(struct fxas2100x_data *data)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +

>> +	pm_runtime_mark_last_busy(dev);

>> +

>> +	return pm_runtime_put_autosuspend(dev);

>> +}

>> +

>> +static int fxas2100x_temp_get(struct fxas2100x_data *data, int 

>> *val)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	unsigned int temp;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = fxas2100x_pm_get(data);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	ret = regmap_field_read(data->regmap_fields[F_TEMP], 

>> &temp);

>> +	if (ret < 0) {

>> +		dev_err(dev, "failed to read temp: %d\n", ret);

>> +		goto data_unlock;

>> +	}

>> +

>> +	*val = sign_extend32(temp, 7);

>> +

>> +	ret = fxas2100x_pm_put(data);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	ret = IIO_VAL_INT;

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_axis_get(struct fxas2100x_data *data, int 

>> index, int *val)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	__be16 axis_be;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = fxas2100x_pm_get(data);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	ret = regmap_bulk_read(data->regmap, 

>> FXAS2100X_AXIS_TO_REG(index),

>> +			       &axis_be, sizeof(axis_be));

>> +	if (ret < 0) {

>> +		dev_err(dev, "failed to read axis: %d: %d\n", 

>> index, ret);

>> +		goto data_unlock;

>> +	}

>> +

>> +	*val = sign_extend32(be16_to_cpu(axis_be), 15);

>> +

>> +	ret = fxas2100x_pm_put(data);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	ret = IIO_VAL_INT;

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_odr_get(struct fxas2100x_data *data, int 

>> *odr)

>> +{

>> +	unsigned int odr_bits;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = regmap_field_read(data->regmap_fields[F_DR], 

>> &odr_bits);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	*odr = fxas2100x_odr_hz_from_value(data, odr_bits);

>> +

>> +	ret = IIO_VAL_INT;

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_odr_set(struct fxas2100x_data *data, int 

>> odr)

>> +{

>> +	int odr_bits;

>> +

>> +	odr_bits = fxas2100x_odr_value_from_hz(data, odr);

>> +	if (odr_bits < 0)

>> +		return odr_bits;

>> +

>> +	return fxas2100x_write(data, F_DR, odr_bits);

>> +}

>> +

>> +static int fxas2100x_lpf_get(struct fxas2100x_data *data, int 

>> *val2)

>> +{

>> +	unsigned int bw_bits;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = regmap_field_read(data->regmap_fields[F_BW], 

>> &bw_bits);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	*val2 = fxas2100x_lpf_bw_from_value(data, bw_bits) * 

>> 10000;

>> +

>> +	ret = IIO_VAL_INT_PLUS_MICRO;

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_lpf_set(struct fxas2100x_data *data, int 

>> bw)

>> +{

>> +	int bw_bits;

>> +	int odr;

>> +	int ret;

>> +

>> +	bw_bits = fxas2100x_lpf_value_from_bw(data, bw);

>> +	if (bw_bits < 0)

>> +		return bw_bits;

>> +

>> +	/*

>> +	 * From table 33 of the device spec, for ODR = 25Hz and 

>> 12.5 value 0.08

>> +	 * is not allowed and for ODR = 12.5 value 0.16 is also 

>> not allowed

>> +	 */

>> +	ret = fxas2100x_odr_get(data, &odr);

>> +	if (ret < 0)

>> +		return -EINVAL;

>> +

>> +	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits 

>> > 0))

>> +		return -EINVAL;

>> +

>> +	return fxas2100x_write(data, F_BW, bw_bits);

>> +}

>> +

>> +static int fxas2100x_hpf_get(struct fxas2100x_data *data, int 

>> *val2)

>> +{

>> +	unsigned int sel_bits;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = regmap_field_read(data->regmap_fields[F_SEL], 

>> &sel_bits);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	*val2 = fxas2100x_hpf_sel_from_value(data, sel_bits);

>> +

>> +	ret = IIO_VAL_INT_PLUS_MICRO;

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_hpf_set(struct fxas2100x_data *data, int 

>> sel)

>> +{

>> +	int sel_bits;

>> +

>> +	sel_bits = fxas2100x_hpf_value_from_sel(data, sel);

>> +	if (sel_bits < 0)

>> +		return sel_bits;

>> +

>> +	return fxas2100x_write(data, F_SEL, sel_bits);

>> +}

>> +

>> +static int fxas2100x_scale_get(struct fxas2100x_data *data, 

>> int *val)

>> +{

>> +	int fs_bits;

>> +	int scale;

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = regmap_field_read(data->regmap_fields[F_FS], 

>> &fs_bits);

>> +	if (ret < 0)

>> +		goto data_unlock;

>> +

>> +	scale = fxas2100x_range_fs_from_value(data, fs_bits);

>> +

>> +	*val = scale;

>> +

>> +	ret = IIO_VAL_FRACTIONAL;

> Given this isn't responsible for setting up val2, I would not

> return IIO_VAL_FRACTIONAL from here, but rather 0 and handle

> the outer return in the caller.  Or set val2 in here...

>

>> +

>> +data_unlock:

>> +	mutex_unlock(&data->lock);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_scale_set(struct fxas2100x_data *data, 

>> int range)

>> +{

>> +	int fs_bits;

>> +

>> +	fs_bits = fxas2100x_range_value_from_fs(data, range);

>> +	if (fs_bits < 0)

>> +		return fs_bits;

>> +

>> +	return fxas2100x_write(data, F_FS, fs_bits);

>> +}

>> +

>> +static int fxas2100x_read_raw(struct iio_dev *indio_dev,

>> +			      struct iio_chan_spec const *chan, 

>> int *val,

>> +			      int *val2, long mask)

>> +{

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +

>> +	switch (mask) {

>> +	case IIO_CHAN_INFO_RAW:

>> +		switch (chan->type) {

>> +		case IIO_TEMP:

>> +			return fxas2100x_temp_get(data, val);

>> +		case IIO_ANGL_VEL:

>> +			return fxas2100x_axis_get(data, 

>> chan->scan_index, val);

>> +		default:

>> +			return -EINVAL;

>> +		}

>> +	case IIO_CHAN_INFO_SCALE:

>> +		switch (chan->type) {

>> +		case IIO_ANGL_VEL:

>> +			*val2 = FXAS2100X_SCALE_FRACTIONAL;

>> +			return fxas2100x_scale_get(data, val);

>> +		default:

>> +			return -EINVAL;

>> +		}

>> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:

>> +		*val = 0;

>> +		return fxas2100x_lpf_get(data, val2);

>> +	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:

>> +		*val = 0;

>> +		return fxas2100x_hpf_get(data, val2);

>> +	case IIO_CHAN_INFO_SAMP_FREQ:

>> +		*val2 = 0;

>> +		return fxas2100x_odr_get(data, val);

>> +	default:

>> +		return -EINVAL;

>> +	}

>> +}

>> +

>> +static int fxas2100x_write_raw(struct iio_dev *indio_dev,

>> +			       struct iio_chan_spec const *chan, 

>> int val,

>> +			       int val2, long mask)

>> +{

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +	int range;

>> +

>> +	switch (mask) {

>> +	case IIO_CHAN_INFO_SAMP_FREQ:

>> +		if (val2)

>> +			return -EINVAL;

>> +

>> +		return fxas2100x_odr_set(data, val);

>> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:

>> +		if (val)

>> +			return -EINVAL;

>> +

>> +		val2 = val2 / 10000;

>> +		return fxas2100x_lpf_set(data, val2);

>> +	case IIO_CHAN_INFO_SCALE:

>> +		switch (chan->type) {

>> +		case IIO_ANGL_VEL:

>> +			range = (((val * 1000 + val2 / 1000) *

>> +				  FXAS2100X_SCALE_FRACTIONAL) / 

>> 1000);

>> +			return fxas2100x_scale_set(data, range);

>> +		default:

>> +			return -EINVAL;

>> +		}

>> +	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:

>> +		return fxas2100x_hpf_set(data, val2);

>> +	default:

>> +		return -EINVAL;

>> +	}

>> +}

>> +

>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 

>> 800");

>> +

>> +static 

>> IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,

>> +		      "0.32 0.16 0.08");

>> +

>> +static 

>> IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,

>> +		      "0.018750 0.009625 0.004875 0.002475");

>> +

>> +static IIO_CONST_ATTR(in_anglvel_scale_available,

>> +		      "125.0 62.5 31.25 15.625 7.8125");

>> +

>> +static struct attribute *fxas2100x_attributes[] = {

>> + 

>> &iio_const_attr_sampling_frequency_available.dev_attr.attr,

>> + 

>> &iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,

>> + 

>> &iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,

>> +	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,

>> +	NULL,

>> +};

>> +

>> +static const struct attribute_group fxas2100x_attrs_group = {

>> +	.attrs = fxas2100x_attributes,

>> +};

>> +

>> +#define FXAS2100X_CHANNEL(_axis) { 

>> \

>> +	.type = IIO_ANGL_VEL, 

>> \

>> +	.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) 

>> |	\

>> +		BIT(IIO_CHAN_INFO_SAMP_FREQ), 

>> \

>> +	.scan_index = CHANNEL_SCAN_INDEX_##_axis, 

>> \

>> +	.scan_type = { 

>> \

>> +		.sign = 's', 

>> \

>> +		.realbits = 16, 

>> \

>> +		.storagebits = 16, 

>> \

>> +		.endianness = IIO_BE, 

>> \

>> +	}, 

>> \

>> +}

>> +

>> +static const struct iio_chan_spec fxas2100x_channels[] = {

>> +	{

>> +		.type = IIO_TEMP,

>> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

>> +		.scan_index = -1,

>> +	},

>> +	FXAS2100X_CHANNEL(X),

>> +	FXAS2100X_CHANNEL(Y),

>> +	FXAS2100X_CHANNEL(Z),

>> +};

>> +

>> +static const struct iio_info fxas2100x_info = {

>> +	.attrs			= &fxas2100x_attrs_group,

>> +	.read_raw		= &fxas2100x_read_raw,

>> +	.write_raw		= &fxas2100x_write_raw,

>> +};

>> +

>> +static irqreturn_t fxas2100x_trigger_handler(int irq, void *p)

>> +{

>> +	struct iio_poll_func *pf = p;

>> +	struct iio_dev *indio_dev = pf->indio_dev;

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +	int ret;

>> +

>> +	mutex_lock(&data->lock);

>> +	ret = regmap_bulk_read(data->regmap, 

>> FXAS2100X_REG_OUT_X_MSB,

>> +			       data->buffer, CHANNEL_SCAN_MAX * 

>> sizeof(s16));

>> +	mutex_unlock(&data->lock);

>> +	if (ret < 0)

>> +		goto notify_done;

>> +

>> +	iio_push_to_buffers_with_timestamp(indio_dev, 

>> data->buffer,

>> +					   pf->timestamp);

>> +

>> +notify_done:

>> +	iio_trigger_notify_done(indio_dev->trig);

>> +

>> +	return IRQ_HANDLED;

>> +}

>> +

>> +static int fxas2100x_chip_init(struct fxas2100x_data *data)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	unsigned int chip_id;

>> +	int ret;

>> +

>> +	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], 

>> &chip_id);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	if (chip_id != FXAS21002_CHIP_ID_1 && chip_id != 

>> FXAS21002_CHIP_ID_2) {

>> +		dev_err(dev, "chip id 0x%02x is not supported\n", 

>> chip_id);

>> +		return -EINVAL;

>> +	}

>> +

>> +	data->chip_id = chip_id;

>> +

>> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	/* Set ODR to 200HZ as default */

>> +	ret = fxas2100x_odr_set(data, 200);

>> +	if (ret < 0)

>> +		dev_err(dev, "failed to set ODR: %d\n", ret);

>> +

>> +	return ret;

>> +}

>> +

>> +static int fxas2100x_data_rdy_trigger_set_state(struct 

>> iio_trigger *trig,

>> +						bool state)

>> +{

>> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +

>> +	return 

>> regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);

>> +}

>> +

>> +static const struct iio_trigger_ops fxas2100x_trigger_ops = {

>> +	.set_trigger_state = 

>> &fxas2100x_data_rdy_trigger_set_state,

>> +};

>> +

>> +static irqreturn_t fxas2100x_data_rdy_trig_poll(int irq, void 

>> *private)

>> +{

>> +	struct iio_dev *indio_dev = private;

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +

>> +	iio_trigger_poll(data->dready_trig);

>> +

>> +	return IRQ_HANDLED;

>> +}

>> +

>> +static int fxas2100x_trigger_probe(struct fxas2100x_data 

>> *data)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	int ret;

>> +

>> +	if (!data->irq)

>> +		return 0;

>> +

>> +	data->dready_trig = devm_iio_trigger_alloc(dev, 

>> "%s-dev%d",

>> + 

>> indio_dev->name,

>> +						   indio_dev->id);

>> +	if (!data->dready_trig)

>> +		return -ENOMEM;

>> +

>> +	ret = devm_request_irq(dev, data->irq, 

>> fxas2100x_data_rdy_trig_poll,

>> +			       IRQF_TRIGGER_RISING, 

>> "fxas2100x_data_ready",

>> +			       data->dready_trig);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	data->dready_trig->dev.parent = dev;

>> +	data->dready_trig->ops = &fxas2100x_trigger_ops;

>> +	iio_trigger_set_drvdata(data->dready_trig, indio_dev);

>> +

>> +	return devm_iio_trigger_register(dev, data->dready_trig);

>> +}

>> +

>> +static int fxas2100x_power_enable(struct fxas2100x_data *data)

>> +{

>> +	struct device *dev = regmap_get_device(data->regmap);

>> +	int ret;

>> +

>> +	data->vdd = devm_regulator_get(dev->parent, "vdd");

>> +	if (IS_ERR(data->vdd)) {

>> +		dev_err(dev, "failed to get Vdd supply\n");

>> +		return PTR_ERR(data->vdd);

>> +	}

>> +

>> +	ret = regulator_enable(data->vdd);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	data->vddio = devm_regulator_get(dev->parent, "vddio");

>> +	if (IS_ERR(data->vddio)) {

>> +		dev_err(dev, "failed to get Vdd_IO supply\n");

> This is rather noisy. Might simply be a deferred result if

> the regulator driver hasn't loaded yet...

>

>> +		regulator_disable(data->vdd);

>> +		return PTR_ERR(data->vddio);

>> +	}

>> +

>> +	ret = regulator_enable(data->vddio);

>> +	if (ret < 0)

> If this fails, should be turning off the earlier regulator.

> I would suggest a goto and one place to handle all error paths

> where cleanup is needed.

>

> As mentioned below, consider devm_add_action_or_reset to

> automatically handle the regulator disables.

>

>> +		return ret;

>> +

>> +	return 0;

>> +}

>> +

>> +static void fxas2100x_power_disable(struct fxas2100x_data 

>> *data)

>> +{

>> +	regulator_disable(data->vdd);

>> +	regulator_disable(data->vddio);

>> +}

>> +

>> +int fxas2100x_core_probe(struct device *dev, struct regmap 

>> *regmap, int irq,

>> +			 const char *name)

>> +{

>> +	struct fxas2100x_data *data;

>> +	struct iio_dev *indio_dev;

>> +	struct regmap_field *f;

>> +	int i;

>> +	int ret;

>> +

>> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));

>> +	if (!indio_dev)

>> +		return -ENOMEM;

>> +

>> +	data = iio_priv(indio_dev);

>> +	dev_set_drvdata(dev, indio_dev);

>> +	data->irq = irq;

>> +	data->regmap = regmap;

>> +

>> +	for (i = 0; i < F_MAX_FIELDS; i++) {

>> +		f = devm_regmap_field_alloc(dev, data->regmap,

>> + 

>> fxas2100x_reg_fields[i]);

>> +		if (IS_ERR(f))

>> +			return PTR_ERR(f);

>> +

>> +		data->regmap_fields[i] = f;

>> +	}

>> +

>> +	mutex_init(&data->lock);

>> +

>> +	ret = fxas2100x_power_enable(data);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	ret = fxas2100x_chip_init(data);

>> +	if (ret < 0)

>> +		goto power_disable;

>> +

>> +	indio_dev->dev.parent = dev;

>> +	indio_dev->channels = fxas2100x_channels;

>> +	indio_dev->num_channels = ARRAY_SIZE(fxas2100x_channels);

>> +	indio_dev->name = name;

>> +	indio_dev->modes = INDIO_DIRECT_MODE;

>> +	indio_dev->info = &fxas2100x_info;

>> +

>> +	ret = fxas2100x_trigger_probe(data);

>> +	if (ret < 0)

>> +		goto power_disable;

>> +

>> +	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,

>> + 

>> iio_pollfunc_store_time,

>> + 

>> fxas2100x_trigger_handler, NULL);

>> +	if (ret < 0)

>

> This results in the unwind ordering being different from the 

> setup.

> If you want to use devm_ functions after the regulators are 

> enabled,

> look at devm_add_action_or_reset to automatically disable the 

> regulators

> and maintain the ordering.

>

> Whilst this probably doesn't lead to any bugs, having different 

> ordering

> in probe and remove makes review harder + often ends up with 

> bugs

> being introduced by later changes to the driver.

>

>> +		goto power_disable;

>> +

>> +	ret = pm_runtime_set_active(dev);

>> +	if (ret)

>> +		goto power_disable;

>> +

>> +	pm_runtime_enable(dev);

>> +	pm_runtime_set_autosuspend_delay(dev, 2000);

>> +	pm_runtime_use_autosuspend(dev);

>> +

>> +	ret = devm_iio_device_register(dev, indio_dev);

>> +	if (ret < 0)

>> +		goto power_disable;

>> +

>> +	return 0;

>> +

>> +power_disable:

>> +	fxas2100x_power_disable(data);

>> +

>> +	return ret;

>> +}

>> +EXPORT_SYMBOL_GPL(fxas2100x_core_probe);

>> +

>> +void fxas2100x_core_remove(struct device *dev)

>> +{

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +

>> +	pm_runtime_disable(dev);

>> +	pm_runtime_set_suspended(dev);

>> +	pm_runtime_put_noidle(dev);

>> +

>> +	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);

>> +	fxas2100x_power_disable(data);

>> +}

>> +EXPORT_SYMBOL_GPL(fxas2100x_core_remove);

>> +

>> +static int __maybe_unused fxas2100x_suspend(struct device 

>> *dev)

>> +{

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

> 	struct fxas2100x_data *data = 

> iio_priv(dev_get_drvdata(dev));

>

> Doesn't loose any meaning and is more compact. (really minor 

> comment

> though).

>

>> +

>> +	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);

>

> Might be worth considering disabling the regulators.

>

>> +

>> +	return 0;

>> +}

>> +

>> +static int __maybe_unused fxas2100x_resume(struct device *dev)

>> +{

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +

>> +	fxas2100x_mode_set(data, data->prev_mode);

> Error handling?  Might not be possible do do anything useful but

> good to know there was an error.

>

>> +

>> +	return 0;

>> +}

>> +

>> +static int __maybe_unused fxas2100x_runtime_suspend(struct 

>> device *dev)

>> +{

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +	int ret;

>> +

>> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);

>> +	if (ret < 0)

>> +		return -EAGAIN;

>> +

>> +	return 0;

>> +}

>> +

>> +static int __maybe_unused fxas2100x_runtime_resume(struct 

>> device *dev)

>> +{

>> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);

>> +	struct fxas2100x_data *data = iio_priv(indio_dev);

>> +	int ret;

>> +

>> +	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_ACTIVE);

>> +	if (ret < 0)

>> +		return -EAGAIN;

>

> That seems unusual.  Why does EAGAIN make sense?

>

>> +

>> +	return 0;

>> +}

>> +

>> +const struct dev_pm_ops fxas2100x_pm_ops = {

>> +	SET_SYSTEM_SLEEP_PM_OPS(fxas2100x_suspend, 

>> fxas2100x_resume)

>> +	SET_RUNTIME_PM_OPS(fxas2100x_runtime_suspend,

>> +			   fxas2100x_runtime_resume, NULL)

>> +};

>> +EXPORT_SYMBOL_GPL(fxas2100x_pm_ops);

>> +

>> +MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");

>> +MODULE_LICENSE("GPL v2");

>> +MODULE_DESCRIPTION("FXAS2100X Gyro driver");

Patch

diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
index 3126cf05e6b9..c168aa63de3b 100644
--- a/drivers/iio/gyro/Kconfig
+++ b/drivers/iio/gyro/Kconfig
@@ -73,6 +73,17 @@  config BMG160_SPI
 	tristate
 	select REGMAP_SPI
 
+config FXAS2100X
+	tristate "NXP FXAS2100X Gyro Sensor"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for NXP FXAS2100X family Tri-axis Gyro
+	  Sensor driver connected via I2C or SPI.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called fxas2100x_i2c or fxas2100x_spi.
+
 config HID_SENSOR_GYRO_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER
diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
index 295ec780c4eb..9e2395185a6e 100644
--- a/drivers/iio/gyro/Makefile
+++ b/drivers/iio/gyro/Makefile
@@ -12,6 +12,7 @@  obj-$(CONFIG_ADXRS450) += adxrs450.o
 obj-$(CONFIG_BMG160) += bmg160_core.o
 obj-$(CONFIG_BMG160_I2C) += bmg160_i2c.o
 obj-$(CONFIG_BMG160_SPI) += bmg160_spi.o
+obj-$(CONFIG_FXAS2100X) += fxas2100x_core.o
 
 obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
 
diff --git a/drivers/iio/gyro/fxas2100x.h b/drivers/iio/gyro/fxas2100x.h
new file mode 100644
index 000000000000..2b503196337f
--- /dev/null
+++ b/drivers/iio/gyro/fxas2100x.h
@@ -0,0 +1,151 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Driver for NXP FXAS2100x Gyroscope - Header
+ *
+ * Copyright (C) 2019 Linaro Ltd.
+ *
+ */
+
+#ifndef FXAS2100X_H_
+#define FXAS2100X_H_
+
+#include <linux/regmap.h>
+
+#define FXAS2100X_REG_STATUS		0x00
+#define FXAS2100X_REG_OUT_X_MSB		0x01
+#define FXAS2100X_REG_OUT_X_LSB		0x02
+#define FXAS2100X_REG_OUT_Y_MSB		0x03
+#define FXAS2100X_REG_OUT_Y_LSB		0x04
+#define FXAS2100X_REG_OUT_Z_MSB		0x05
+#define FXAS2100X_REG_OUT_Z_LSB		0x06
+#define FXAS2100X_REG_DR_STATUS		0x07
+#define FXAS2100X_REG_F_STATUS		0x08
+#define FXAS2100X_REG_F_SETUP		0x09
+#define FXAS2100X_REG_F_EVENT		0x0A
+#define FXAS2100X_REG_INT_SRC_FLAG	0x0B
+#define FXAS2100X_REG_WHO_AM_I		0x0C
+#define FXAS2100X_REG_CTRL0		0x0D
+#define FXAS2100X_REG_RT_CFG		0x0E
+#define FXAS2100X_REG_RT_SRC		0x0F
+#define FXAS2100X_REG_RT_THS		0x10
+#define FXAS2100X_REG_RT_COUNT		0x11
+#define FXAS2100X_REG_TEMP		0x12
+#define FXAS2100X_REG_CTRL1		0x13
+#define FXAS2100X_REG_CTRL2		0x14
+#define FXAS2100X_REG_CTRL3		0x15
+
+enum fxas2100x_fields {
+	F_DR_STATUS,
+	F_OUT_X_MSB,
+	F_OUT_X_LSB,
+	F_OUT_Y_MSB,
+	F_OUT_Y_LSB,
+	F_OUT_Z_MSB,
+	F_OUT_Z_LSB,
+	/* DR_STATUS */
+	F_ZYX_OW, F_Z_OW, F_Y_OW, F_X_OW, F_ZYX_DR, F_Z_DR, F_Y_DR, F_X_DR,
+	/* F_STATUS */
+	F_OVF, F_WMKF, F_CNT,
+	/* F_SETUP */
+	F_MODE, F_WMRK,
+	/* F_EVENT */
+	F_EVENT, FE_TIME,
+	/* INT_SOURCE_FLAG */
+	F_BOOTEND, F_SRC_FIFO, F_SRC_RT, F_SRC_DRDY,
+	/* WHO_AM_I */
+	F_WHO_AM_I,
+	/* CTRL_REG0 */
+	F_BW, F_SPIW, F_SEL, F_HPF_EN, F_FS,
+	/* RT_CFG */
+	F_ELE, F_ZTEFE, F_YTEFE, F_XTEFE,
+	/* RT_SRC */
+	F_EA, F_ZRT, F_ZRT_POL, F_YRT, F_YRT_POL, F_XRT, F_XRT_POL,
+	/* RT_THS */
+	F_DBCNTM, F_THS,
+	/* RT_COUNT */
+	F_RT_COUNT,
+	/* TEMP */
+	F_TEMP,
+	/* CTRL_REG1 */
+	F_RST, F_ST, F_DR, F_ACTIVE, F_READY,
+	/* CTRL_REG2 */
+	F_INT_CFG_FIFO, F_INT_EN_FIFO, F_INT_CFG_RT, F_INT_EN_RT,
+	F_INT_CFG_DRDY, F_INT_EN_DRDY, F_IPOL, F_PP_OD,
+	/* CTRL_REG3 */
+	F_WRAPTOONE, F_EXTCTRLEN, F_FS_DOUBLE,
+	/* MAX FIELDS */
+	F_MAX_FIELDS,
+};
+
+static const struct reg_field fxas2100x_reg_fields[] = {
+	[F_DR_STATUS]		= REG_FIELD(FXAS2100X_REG_STATUS, 0, 7),
+	[F_OUT_X_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_X_MSB, 0, 7),
+	[F_OUT_X_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_X_LSB, 0, 7),
+	[F_OUT_Y_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_Y_MSB, 0, 7),
+	[F_OUT_Y_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_Y_LSB, 0, 7),
+	[F_OUT_Z_MSB]		= REG_FIELD(FXAS2100X_REG_OUT_Z_MSB, 0, 7),
+	[F_OUT_Z_LSB]		= REG_FIELD(FXAS2100X_REG_OUT_Z_LSB, 0, 7),
+	[F_ZYX_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 7, 7),
+	[F_Z_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 6, 6),
+	[F_Y_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 5, 5),
+	[F_X_OW]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 4, 4),
+	[F_ZYX_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 3, 3),
+	[F_Z_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 2, 2),
+	[F_Y_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 1, 1),
+	[F_X_DR]		= REG_FIELD(FXAS2100X_REG_DR_STATUS, 0, 0),
+	[F_OVF]			= REG_FIELD(FXAS2100X_REG_F_STATUS, 7, 7),
+	[F_WMKF]		= REG_FIELD(FXAS2100X_REG_F_STATUS, 6, 6),
+	[F_CNT]			= REG_FIELD(FXAS2100X_REG_F_STATUS, 0, 5),
+	[F_MODE]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 6, 7),
+	[F_WMRK]		= REG_FIELD(FXAS2100X_REG_F_SETUP, 0, 5),
+	[F_EVENT]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 5, 5),
+	[FE_TIME]		= REG_FIELD(FXAS2100X_REG_F_EVENT, 0, 4),
+	[F_BOOTEND]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 3, 3),
+	[F_SRC_FIFO]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 2, 2),
+	[F_SRC_RT]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 1, 1),
+	[F_SRC_DRDY]		= REG_FIELD(FXAS2100X_REG_INT_SRC_FLAG, 0, 0),
+	[F_WHO_AM_I]		= REG_FIELD(FXAS2100X_REG_WHO_AM_I, 0, 7),
+	[F_BW]			= REG_FIELD(FXAS2100X_REG_CTRL0, 6, 7),
+	[F_SPIW]		= REG_FIELD(FXAS2100X_REG_CTRL0, 5, 5),
+	[F_SEL]			= REG_FIELD(FXAS2100X_REG_CTRL0, 3, 4),
+	[F_HPF_EN]		= REG_FIELD(FXAS2100X_REG_CTRL0, 2, 2),
+	[F_FS]			= REG_FIELD(FXAS2100X_REG_CTRL0, 0, 1),
+	[F_ELE]			= REG_FIELD(FXAS2100X_REG_RT_CFG, 3, 3),
+	[F_ZTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 2, 2),
+	[F_YTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 1, 1),
+	[F_XTEFE]		= REG_FIELD(FXAS2100X_REG_RT_CFG, 0, 0),
+	[F_EA]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 6, 6),
+	[F_ZRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 5, 5),
+	[F_ZRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 4, 4),
+	[F_YRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 3, 3),
+	[F_YRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 2, 2),
+	[F_XRT]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 1, 1),
+	[F_XRT_POL]		= REG_FIELD(FXAS2100X_REG_RT_SRC, 0, 0),
+	[F_DBCNTM]		= REG_FIELD(FXAS2100X_REG_RT_THS, 7, 7),
+	[F_THS]			= REG_FIELD(FXAS2100X_REG_RT_SRC, 0, 6),
+	[F_RT_COUNT]		= REG_FIELD(FXAS2100X_REG_RT_COUNT, 0, 7),
+	[F_TEMP]		= REG_FIELD(FXAS2100X_REG_TEMP, 0, 7),
+	[F_RST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 6, 6),
+	[F_ST]			= REG_FIELD(FXAS2100X_REG_CTRL1, 5, 5),
+	[F_DR]			= REG_FIELD(FXAS2100X_REG_CTRL1, 2, 4),
+	[F_ACTIVE]		= REG_FIELD(FXAS2100X_REG_CTRL1, 1, 1),
+	[F_READY]		= REG_FIELD(FXAS2100X_REG_CTRL1, 0, 0),
+	[F_INT_CFG_FIFO]	= REG_FIELD(FXAS2100X_REG_CTRL2, 7, 7),
+	[F_INT_EN_FIFO]		= REG_FIELD(FXAS2100X_REG_CTRL2, 6, 6),
+	[F_INT_CFG_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 5, 5),
+	[F_INT_EN_RT]		= REG_FIELD(FXAS2100X_REG_CTRL2, 4, 4),
+	[F_INT_CFG_DRDY]	= REG_FIELD(FXAS2100X_REG_CTRL2, 3, 3),
+	[F_INT_EN_DRDY]		= REG_FIELD(FXAS2100X_REG_CTRL2, 2, 2),
+	[F_IPOL]		= REG_FIELD(FXAS2100X_REG_CTRL2, 1, 1),
+	[F_PP_OD]		= REG_FIELD(FXAS2100X_REG_CTRL2, 0, 0),
+	[F_WRAPTOONE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 3, 3),
+	[F_EXTCTRLEN]		= REG_FIELD(FXAS2100X_REG_CTRL3, 2, 2),
+	[F_FS_DOUBLE]		= REG_FIELD(FXAS2100X_REG_CTRL3, 0, 0),
+};
+
+extern const struct dev_pm_ops fxas2100x_pm_ops;
+
+int fxas2100x_core_probe(struct device *dev, struct regmap *regmap, int irq,
+			 const char *name);
+void fxas2100x_core_remove(struct device *dev);
+#endif
diff --git a/drivers/iio/gyro/fxas2100x_core.c b/drivers/iio/gyro/fxas2100x_core.c
new file mode 100644
index 000000000000..9c0ba283fea8
--- /dev/null
+++ b/drivers/iio/gyro/fxas2100x_core.c
@@ -0,0 +1,931 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for NXP FXAS2100x Gyroscope - Core
+ *
+ * Copyright (C) 2019 Linaro Ltd.
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#include "fxas2100x.h"
+
+#define FXAS21002_CHIP_ID_1	0xD6
+#define FXAS21002_CHIP_ID_2	0xD7
+
+enum fxas2100x_mode_state {
+	FXAS2100X_MODE_STANDBY,
+	FXAS2100X_MODE_READY,
+	FXAS2100X_MODE_ACTIVE,
+};
+
+#define FXAS2100X_STANDBY_ACTIVE_TIME_MS	62
+#define FXAS2100X_READY_ACTIVE_TIME_MS		7
+
+#define FXAS2100X_ODR_LIST_MAX		10
+
+#define FXAS2100X_SCALE_FRACTIONAL	32
+#define FXAS2100X_RANGE_LIMIT_DOUBLE	2000
+
+#define FXAS2100X_AXIS_TO_REG(axis)	(FXAS2100X_REG_OUT_X_MSB + ((axis) * 2))
+
+static const int fxas2100x_odr_values[] = {
+	800, 400, 200, 100, 50, 25, 12, 12
+};
+
+/*
+ * These values are taken from the low-pass filter cutoff frequency calculated
+ * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 0.32
+ * => LPF cutoff frequency = 800 * 0.32 = 256 Hz
+ */
+static const int fxas2100x_lpf_values[] = {
+	32, 16, 8
+};
+
+/*
+ * These values are taken from the high-pass filter cutoff frequency calculated
+ * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 0.018750
+ * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz
+ */
+static const int fxas2100x_hpf_values[] = {
+	18750, 9625, 4875, 2475
+};
+
+static const int fxas2100x_range_values[] = {
+	4000, 2000, 1000, 500, 250
+};
+
+struct fxas2100x_data {
+	u8 chip_id;
+	enum fxas2100x_mode_state mode;
+	enum fxas2100x_mode_state prev_mode;
+
+	struct mutex lock;		/* serialize data access */
+	struct regmap *regmap;
+	struct regmap_field *regmap_fields[F_MAX_FIELDS];
+	s16 buffer[8];
+
+	struct iio_trigger *dready_trig;
+	int irq;
+
+	struct regulator *vdd;
+	struct regulator *vddio;
+};
+
+enum fxas2100x_channel_index {
+	CHANNEL_SCAN_INDEX_X,
+	CHANNEL_SCAN_INDEX_Y,
+	CHANNEL_SCAN_INDEX_Z,
+	CHANNEL_SCAN_MAX,
+};
+
+static int fxas2100x_odr_hz_from_value(struct fxas2100x_data *data, u8 value)
+{
+	int odr_value_max = ARRAY_SIZE(fxas2100x_odr_values) - 1;
+
+	value = min_t(u8, value, odr_value_max);
+
+	return fxas2100x_odr_values[value];
+}
+
+static int fxas2100x_odr_value_from_hz(struct fxas2100x_data *data,
+				       unsigned int hz)
+{
+	int odr_table_size = ARRAY_SIZE(fxas2100x_odr_values);
+	int i;
+
+	for (i = 0; i < odr_table_size; i++)
+		if (fxas2100x_odr_values[i] == hz)
+			return i;
+
+	return -EINVAL;
+}
+
+static int fxas2100x_lpf_bw_from_value(struct fxas2100x_data *data, u8 value)
+{
+	int lpf_value_max = ARRAY_SIZE(fxas2100x_lpf_values) - 1;
+
+	value = min_t(u8, value, lpf_value_max);
+
+	return fxas2100x_lpf_values[value];
+}
+
+static int fxas2100x_lpf_value_from_bw(struct fxas2100x_data *data,
+				       unsigned int hz)
+{
+	int lpf_table_size = ARRAY_SIZE(fxas2100x_lpf_values);
+	int i;
+
+	for (i = 0; i < lpf_table_size; i++)
+		if (fxas2100x_lpf_values[i] == hz)
+			return i;
+
+	return -EINVAL;
+}
+
+static int fxas2100x_hpf_sel_from_value(struct fxas2100x_data *data, u8 value)
+{
+	int hpf_value_max = ARRAY_SIZE(fxas2100x_hpf_values) - 1;
+
+	value = min_t(u8, value, hpf_value_max);
+
+	return fxas2100x_hpf_values[value];
+}
+
+static int fxas2100x_hpf_value_from_sel(struct fxas2100x_data *data,
+					unsigned int hz)
+{
+	int hpf_table_size = ARRAY_SIZE(fxas2100x_hpf_values);
+	int i;
+
+	for (i = 0; i < hpf_table_size; i++)
+		if (fxas2100x_hpf_values[i] == hz)
+			return i;
+
+	return -EINVAL;
+}
+
+static int fxas2100x_range_fs_from_value(struct fxas2100x_data *data,
+					 u8 value)
+{
+	int range_value_max = ARRAY_SIZE(fxas2100x_range_values) - 1;
+	unsigned int fs_double;
+	int ret;
+
+	/* We need to check if FS_DOUBLE is enabled to offset the value */
+	ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], &fs_double);
+	if (ret < 0)
+		return ret;
+
+	if (!fs_double)
+		value += 1;
+
+	value = min_t(u8, value, range_value_max);
+
+	return fxas2100x_range_values[value];
+}
+
+static int fxas2100x_range_value_from_fs(struct fxas2100x_data *data,
+					 unsigned int range)
+{
+	int range_table_size = ARRAY_SIZE(fxas2100x_range_values);
+	bool found = false;
+	int ret;
+	int i;
+
+	for (i = 0; i < range_table_size; i++)
+		if (fxas2100x_range_values[i] == range)
+			found = true;
+	if (!found)
+		return -EINVAL;
+
+	if (range > FXAS2100X_RANGE_LIMIT_DOUBLE)
+		ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 1);
+	else
+		ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], 0);
+	if (ret < 0)
+		return ret;
+
+	return i;
+}
+
+static int fxas2100x_mode_get(struct fxas2100x_data *data)
+{
+	unsigned int active;
+	unsigned int ready;
+	int ret;
+
+	ret = regmap_field_read(data->regmap_fields[F_ACTIVE], &active);
+	if (ret < 0)
+		return ret;
+	if (active)
+		return FXAS2100X_MODE_ACTIVE;
+
+	ret = regmap_field_read(data->regmap_fields[F_READY], &ready);
+	if (ret < 0)
+		return ret;
+	if (ready)
+		return FXAS2100X_MODE_READY;
+
+	return FXAS2100X_MODE_STANDBY;
+}
+
+static int fxas2100x_mode_set(struct fxas2100x_data *data,
+			      enum fxas2100x_mode_state mode)
+{
+	int ret;
+
+	if (mode > FXAS2100X_MODE_ACTIVE)
+		return -EINVAL;
+
+	if (mode == data->mode)
+		return 0;
+
+	if (mode == FXAS2100X_MODE_READY)
+		ret = regmap_field_write(data->regmap_fields[F_READY], 1);
+	else
+		ret = regmap_field_write(data->regmap_fields[F_READY], 0);
+	if (ret < 0)
+		return ret;
+
+	if (mode == FXAS2100X_MODE_ACTIVE)
+		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 1);
+	else
+		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 0);
+	if (ret < 0)
+		return ret;
+
+	/* if going to active wait the setup times */
+	if (mode == FXAS2100X_MODE_ACTIVE)
+		if (data->mode == FXAS2100X_MODE_STANDBY)
+			msleep_interruptible(FXAS2100X_STANDBY_ACTIVE_TIME_MS);
+	if (data->mode == FXAS2100X_MODE_READY)
+		msleep_interruptible(FXAS2100X_READY_ACTIVE_TIME_MS);
+
+	data->prev_mode = data->mode;
+	data->mode = mode;
+
+	return ret;
+}
+
+static int fxas2100x_write(struct fxas2100x_data *data,
+			   enum fxas2100x_fields field, int bits)
+{
+	int actual_mode;
+	int ret;
+
+	mutex_lock(&data->lock);
+
+	actual_mode = fxas2100x_mode_get(data);
+	if (actual_mode < 0) {
+		ret = actual_mode;
+		goto out_unlock;
+	}
+
+	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);
+	if (ret < 0)
+		goto out_unlock;
+
+	ret = regmap_field_write(data->regmap_fields[field], bits);
+	if (ret < 0)
+		goto out_unlock;
+
+	ret = fxas2100x_mode_set(data, data->prev_mode);
+
+out_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int  fxas2100x_pm_get(struct fxas2100x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0)
+		pm_runtime_put_noidle(dev);
+
+	return ret;
+}
+
+static int  fxas2100x_pm_put(struct fxas2100x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+
+	pm_runtime_mark_last_busy(dev);
+
+	return pm_runtime_put_autosuspend(dev);
+}
+
+static int fxas2100x_temp_get(struct fxas2100x_data *data, int *val)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	unsigned int temp;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = fxas2100x_pm_get(data);
+	if (ret < 0)
+		goto data_unlock;
+
+	ret = regmap_field_read(data->regmap_fields[F_TEMP], &temp);
+	if (ret < 0) {
+		dev_err(dev, "failed to read temp: %d\n", ret);
+		goto data_unlock;
+	}
+
+	*val = sign_extend32(temp, 7);
+
+	ret = fxas2100x_pm_put(data);
+	if (ret < 0)
+		goto data_unlock;
+
+	ret = IIO_VAL_INT;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_axis_get(struct fxas2100x_data *data, int index, int *val)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	__be16 axis_be;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = fxas2100x_pm_get(data);
+	if (ret < 0)
+		goto data_unlock;
+
+	ret = regmap_bulk_read(data->regmap, FXAS2100X_AXIS_TO_REG(index),
+			       &axis_be, sizeof(axis_be));
+	if (ret < 0) {
+		dev_err(dev, "failed to read axis: %d: %d\n", index, ret);
+		goto data_unlock;
+	}
+
+	*val = sign_extend32(be16_to_cpu(axis_be), 15);
+
+	ret = fxas2100x_pm_put(data);
+	if (ret < 0)
+		goto data_unlock;
+
+	ret = IIO_VAL_INT;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_odr_get(struct fxas2100x_data *data, int *odr)
+{
+	unsigned int odr_bits;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);
+	if (ret < 0)
+		goto data_unlock;
+
+	*odr = fxas2100x_odr_hz_from_value(data, odr_bits);
+
+	ret = IIO_VAL_INT;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_odr_set(struct fxas2100x_data *data, int odr)
+{
+	int odr_bits;
+
+	odr_bits = fxas2100x_odr_value_from_hz(data, odr);
+	if (odr_bits < 0)
+		return odr_bits;
+
+	return fxas2100x_write(data, F_DR, odr_bits);
+}
+
+static int fxas2100x_lpf_get(struct fxas2100x_data *data, int *val2)
+{
+	unsigned int bw_bits;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);
+	if (ret < 0)
+		goto data_unlock;
+
+	*val2 = fxas2100x_lpf_bw_from_value(data, bw_bits) * 10000;
+
+	ret = IIO_VAL_INT_PLUS_MICRO;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_lpf_set(struct fxas2100x_data *data, int bw)
+{
+	int bw_bits;
+	int odr;
+	int ret;
+
+	bw_bits = fxas2100x_lpf_value_from_bw(data, bw);
+	if (bw_bits < 0)
+		return bw_bits;
+
+	/*
+	 * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08
+	 * is not allowed and for ODR = 12.5 value 0.16 is also not allowed
+	 */
+	ret = fxas2100x_odr_get(data, &odr);
+	if (ret < 0)
+		return -EINVAL;
+
+	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))
+		return -EINVAL;
+
+	return fxas2100x_write(data, F_BW, bw_bits);
+}
+
+static int fxas2100x_hpf_get(struct fxas2100x_data *data, int *val2)
+{
+	unsigned int sel_bits;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);
+	if (ret < 0)
+		goto data_unlock;
+
+	*val2 = fxas2100x_hpf_sel_from_value(data, sel_bits);
+
+	ret = IIO_VAL_INT_PLUS_MICRO;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_hpf_set(struct fxas2100x_data *data, int sel)
+{
+	int sel_bits;
+
+	sel_bits = fxas2100x_hpf_value_from_sel(data, sel);
+	if (sel_bits < 0)
+		return sel_bits;
+
+	return fxas2100x_write(data, F_SEL, sel_bits);
+}
+
+static int fxas2100x_scale_get(struct fxas2100x_data *data, int *val)
+{
+	int fs_bits;
+	int scale;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);
+	if (ret < 0)
+		goto data_unlock;
+
+	scale = fxas2100x_range_fs_from_value(data, fs_bits);
+
+	*val = scale;
+
+	ret = IIO_VAL_FRACTIONAL;
+
+data_unlock:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int fxas2100x_scale_set(struct fxas2100x_data *data, int range)
+{
+	int fs_bits;
+
+	fs_bits = fxas2100x_range_value_from_fs(data, range);
+	if (fs_bits < 0)
+		return fs_bits;
+
+	return fxas2100x_write(data, F_FS, fs_bits);
+}
+
+static int fxas2100x_read_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan, int *val,
+			      int *val2, long mask)
+{
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_TEMP:
+			return fxas2100x_temp_get(data, val);
+		case IIO_ANGL_VEL:
+			return fxas2100x_axis_get(data, chan->scan_index, val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			*val2 = FXAS2100X_SCALE_FRACTIONAL;
+			return fxas2100x_scale_get(data, val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		*val = 0;
+		return fxas2100x_lpf_get(data, val2);
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		*val = 0;
+		return fxas2100x_hpf_get(data, val2);
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val2 = 0;
+		return fxas2100x_odr_get(data, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int fxas2100x_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan, int val,
+			       int val2, long mask)
+{
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+	int range;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (val2)
+			return -EINVAL;
+
+		return fxas2100x_odr_set(data, val);
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		if (val)
+			return -EINVAL;
+
+		val2 = val2 / 10000;
+		return fxas2100x_lpf_set(data, val2);
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ANGL_VEL:
+			range = (((val * 1000 + val2 / 1000) *
+				  FXAS2100X_SCALE_FRACTIONAL) / 1000);
+			return fxas2100x_scale_set(data, range);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		return fxas2100x_hpf_set(data, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");
+
+static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,
+		      "0.32 0.16 0.08");
+
+static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,
+		      "0.018750 0.009625 0.004875 0.002475");
+
+static IIO_CONST_ATTR(in_anglvel_scale_available,
+		      "125.0 62.5 31.25 15.625 7.8125");
+
+static struct attribute *fxas2100x_attributes[] = {
+	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group fxas2100x_attrs_group = {
+	.attrs = fxas2100x_attributes,
+};
+
+#define FXAS2100X_CHANNEL(_axis) {					\
+	.type = IIO_ANGL_VEL,						\
+	.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) |	\
+		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
+	.scan_index = CHANNEL_SCAN_INDEX_##_axis,			\
+	.scan_type = {							\
+		.sign = 's',						\
+		.realbits = 16,						\
+		.storagebits = 16,					\
+		.endianness = IIO_BE,					\
+	},								\
+}
+
+static const struct iio_chan_spec fxas2100x_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.scan_index = -1,
+	},
+	FXAS2100X_CHANNEL(X),
+	FXAS2100X_CHANNEL(Y),
+	FXAS2100X_CHANNEL(Z),
+};
+
+static const struct iio_info fxas2100x_info = {
+	.attrs			= &fxas2100x_attrs_group,
+	.read_raw		= &fxas2100x_read_raw,
+	.write_raw		= &fxas2100x_write_raw,
+};
+
+static irqreturn_t fxas2100x_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_bulk_read(data->regmap, FXAS2100X_REG_OUT_X_MSB,
+			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
+	mutex_unlock(&data->lock);
+	if (ret < 0)
+		goto notify_done;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+					   pf->timestamp);
+
+notify_done:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int fxas2100x_chip_init(struct fxas2100x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	unsigned int chip_id;
+	int ret;
+
+	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);
+	if (ret < 0)
+		return ret;
+
+	if (chip_id != FXAS21002_CHIP_ID_1 && chip_id != FXAS21002_CHIP_ID_2) {
+		dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);
+		return -EINVAL;
+	}
+
+	data->chip_id = chip_id;
+
+	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);
+	if (ret < 0)
+		return ret;
+
+	/* Set ODR to 200HZ as default */
+	ret = fxas2100x_odr_set(data, 200);
+	if (ret < 0)
+		dev_err(dev, "failed to set ODR: %d\n", ret);
+
+	return ret;
+}
+
+static int fxas2100x_data_rdy_trigger_set_state(struct iio_trigger *trig,
+						bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);
+}
+
+static const struct iio_trigger_ops fxas2100x_trigger_ops = {
+	.set_trigger_state = &fxas2100x_data_rdy_trigger_set_state,
+};
+
+static irqreturn_t fxas2100x_data_rdy_trig_poll(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	iio_trigger_poll(data->dready_trig);
+
+	return IRQ_HANDLED;
+}
+
+static int fxas2100x_trigger_probe(struct fxas2100x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	int ret;
+
+	if (!data->irq)
+		return 0;
+
+	data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+						   indio_dev->name,
+						   indio_dev->id);
+	if (!data->dready_trig)
+		return -ENOMEM;
+
+	ret = devm_request_irq(dev, data->irq, fxas2100x_data_rdy_trig_poll,
+			       IRQF_TRIGGER_RISING, "fxas2100x_data_ready",
+			       data->dready_trig);
+	if (ret < 0)
+		return ret;
+
+	data->dready_trig->dev.parent = dev;
+	data->dready_trig->ops = &fxas2100x_trigger_ops;
+	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
+
+	return devm_iio_trigger_register(dev, data->dready_trig);
+}
+
+static int fxas2100x_power_enable(struct fxas2100x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+
+	data->vdd = devm_regulator_get(dev->parent, "vdd");
+	if (IS_ERR(data->vdd)) {
+		dev_err(dev, "failed to get Vdd supply\n");
+		return PTR_ERR(data->vdd);
+	}
+
+	ret = regulator_enable(data->vdd);
+	if (ret < 0)
+		return ret;
+
+	data->vddio = devm_regulator_get(dev->parent, "vddio");
+	if (IS_ERR(data->vddio)) {
+		dev_err(dev, "failed to get Vdd_IO supply\n");
+		regulator_disable(data->vdd);
+		return PTR_ERR(data->vddio);
+	}
+
+	ret = regulator_enable(data->vddio);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void fxas2100x_power_disable(struct fxas2100x_data *data)
+{
+	regulator_disable(data->vdd);
+	regulator_disable(data->vddio);
+}
+
+int fxas2100x_core_probe(struct device *dev, struct regmap *regmap, int irq,
+			 const char *name)
+{
+	struct fxas2100x_data *data;
+	struct iio_dev *indio_dev;
+	struct regmap_field *f;
+	int i;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	dev_set_drvdata(dev, indio_dev);
+	data->irq = irq;
+	data->regmap = regmap;
+
+	for (i = 0; i < F_MAX_FIELDS; i++) {
+		f = devm_regmap_field_alloc(dev, data->regmap,
+					    fxas2100x_reg_fields[i]);
+		if (IS_ERR(f))
+			return PTR_ERR(f);
+
+		data->regmap_fields[i] = f;
+	}
+
+	mutex_init(&data->lock);
+
+	ret = fxas2100x_power_enable(data);
+	if (ret < 0)
+		return ret;
+
+	ret = fxas2100x_chip_init(data);
+	if (ret < 0)
+		goto power_disable;
+
+	indio_dev->dev.parent = dev;
+	indio_dev->channels = fxas2100x_channels;
+	indio_dev->num_channels = ARRAY_SIZE(fxas2100x_channels);
+	indio_dev->name = name;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &fxas2100x_info;
+
+	ret = fxas2100x_trigger_probe(data);
+	if (ret < 0)
+		goto power_disable;
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
+					      iio_pollfunc_store_time,
+					      fxas2100x_trigger_handler, NULL);
+	if (ret < 0)
+		goto power_disable;
+
+	ret = pm_runtime_set_active(dev);
+	if (ret)
+		goto power_disable;
+
+	pm_runtime_enable(dev);
+	pm_runtime_set_autosuspend_delay(dev, 2000);
+	pm_runtime_use_autosuspend(dev);
+
+	ret = devm_iio_device_register(dev, indio_dev);
+	if (ret < 0)
+		goto power_disable;
+
+	return 0;
+
+power_disable:
+	fxas2100x_power_disable(data);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fxas2100x_core_probe);
+
+void fxas2100x_core_remove(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+	pm_runtime_put_noidle(dev);
+
+	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);
+	fxas2100x_power_disable(data);
+}
+EXPORT_SYMBOL_GPL(fxas2100x_core_remove);
+
+static int __maybe_unused fxas2100x_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	fxas2100x_mode_set(data, FXAS2100X_MODE_STANDBY);
+
+	return 0;
+}
+
+static int __maybe_unused fxas2100x_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+
+	fxas2100x_mode_set(data, data->prev_mode);
+
+	return 0;
+}
+
+static int __maybe_unused fxas2100x_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_READY);
+	if (ret < 0)
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int __maybe_unused fxas2100x_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct fxas2100x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = fxas2100x_mode_set(data, FXAS2100X_MODE_ACTIVE);
+	if (ret < 0)
+		return -EAGAIN;
+
+	return 0;
+}
+
+const struct dev_pm_ops fxas2100x_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(fxas2100x_suspend, fxas2100x_resume)
+	SET_RUNTIME_PM_OPS(fxas2100x_runtime_suspend,
+			   fxas2100x_runtime_resume, NULL)
+};
+EXPORT_SYMBOL_GPL(fxas2100x_pm_ops);
+
+MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("FXAS2100X Gyro driver");