iio: Add SEMTECH SX9310/9311 sensor driver
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Message ID 20200121150658.1.I1f56fe698017f22d6e825c913c256d5afc2ad69f@changeid
State New
Headers show
Series
  • iio: Add SEMTECH SX9310/9311 sensor driver
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Commit Message

Daniel Campello Jan. 21, 2020, 10:08 p.m. UTC
Add SEMTECH SX9310/9311 driver.

The device has the following entry points:

Usual frequency:
- sampling_frequency
- sampling_frequency_available

Instant reading of current values for different sensors:
- in_proximity0_raw
- in_proximity1_raw
- in_proximity2_raw
- in_proximity3_raw
- in_proximity0-proximity0_raw
- in_proximity1-proximity1_raw
- in_proximity2-proximity2_raw
- in_proximity3-proximity3_raw
and associated events in events/

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Enrico Granata <egranata@chromium.org>
Signed-off-by: Daniel Campello <campello@chromium.org>
---

 drivers/iio/proximity/Kconfig  |   14 +
 drivers/iio/proximity/Makefile |    1 +
 drivers/iio/proximity/sx9310.c | 1100 ++++++++++++++++++++++++++++++++
 3 files changed, 1115 insertions(+)
 create mode 100644 drivers/iio/proximity/sx9310.c

--
2.25.0.341.g760bfbb309-goog

Comments

Daniel Campello Jan. 31, 2020, 11:33 p.m. UTC | #1
Hello,

Are there any updated regarding this patch?

Thanks for your time!
Daniel
Jonathan Cameron Feb. 2, 2020, 5:17 p.m. UTC | #2
On Tue, 21 Jan 2020 15:08:24 -0700
Daniel Campello <campello@chromium.org> wrote:

> Add SEMTECH SX9310/9311 driver.
> 
> The device has the following entry points:
> 
> Usual frequency:
> - sampling_frequency
> - sampling_frequency_available
> 
> Instant reading of current values for different sensors:
> - in_proximity0_raw
> - in_proximity1_raw
> - in_proximity2_raw
> - in_proximity3_raw
> - in_proximity0-proximity0_raw

That's unusual as interfaces go and would normally make
people expect a value of 0...

Having had a look at the data sheet I think these differential
channels are actually an attempt to subtract the low pass
version of the same channel from the current version
(effectively a high pass filter).  Given there is
also a low pass filter on the raw input, it looks like
we really have some sort of bandpass filter.
The actual filter is horrible as you have different thresholds
for moving the average one way or the other.

So is it actually useful to output proximityX_raw at all?
They sound liable to be extremely messy for userspace to
deal with.  I would just report 4 simple non differential
channels. Ideally we'd have a generic description for that
filter, but its so 'weird' I'm not sure we'll be able to come
up with one.

The 4th sensor is interesting, as a combination of the other 3.
We currently have no way of representing that.  Hmm. This may
be a rare case for using extend_name to make it clear what it
is.

> - in_proximity1-proximity1_raw
> - in_proximity2-proximity2_raw
> - in_proximity3-proximity3_raw
> and associated events in events/
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Signed-off-by: Enrico Granata <egranata@chromium.org>
> Signed-off-by: Daniel Campello <campello@chromium.org>
> ---
> 
>  drivers/iio/proximity/Kconfig  |   14 +
>  drivers/iio/proximity/Makefile |    1 +
>  drivers/iio/proximity/sx9310.c | 1100 ++++++++++++++++++++++++++++++++
>  3 files changed, 1115 insertions(+)
>  create mode 100644 drivers/iio/proximity/sx9310.c
> 
> diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
> index d53601447da433..fd82962f2e3abc 100644
> --- a/drivers/iio/proximity/Kconfig
> +++ b/drivers/iio/proximity/Kconfig
> @@ -86,6 +86,20 @@ config SRF04
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called srf04.
> 
> +config SX9310
> +	tristate "SX9310/SX9311 Semtech proximity sensor"
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +	select REGMAP_I2C
> +	depends on I2C
> +	depends on ACPI
> +	help
> +	  Say Y here to build a driver for Semtech's SX9310/SX9311 capacitive
> +	  proximity/button sensor.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called sx9310.
> +
>  config SX9500
>  	tristate "SX9500 Semtech proximity sensor"
>  	select IIO_BUFFER
> diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
> index 0bb5f9de13d657..b7ebd94a1bb6ed 100644
> --- a/drivers/iio/proximity/Makefile
> +++ b/drivers/iio/proximity/Makefile
> @@ -11,6 +11,7 @@ obj-$(CONFIG_MB1232)		+= mb1232.o
>  obj-$(CONFIG_RFD77402)		+= rfd77402.o
>  obj-$(CONFIG_SRF04)		+= srf04.o
>  obj-$(CONFIG_SRF08)		+= srf08.o
> +obj-$(CONFIG_SX9310)		+= sx9310.o
>  obj-$(CONFIG_SX9500)		+= sx9500.o
>  obj-$(CONFIG_VL53L0X_I2C)	+= vl53l0x-i2c.o
> 
> diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
> new file mode 100644
> index 00000000000000..427282cb26dbc5
> --- /dev/null
> +++ b/drivers/iio/proximity/sx9310.c
> @@ -0,0 +1,1100 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2018 Google LLC.
> + *
> + * Driver for Semtech's SX9310/SX9311 capacitive proximity/button solution.
> + * Based on SX9500 driver and Semtech driver using the input framework
> + * <https://my.syncplicity.com/share/teouwsim8niiaud/
> + *          linux-driver-SX9310_NoSmartHSensing>.
> + * Reworked April 2019 by Evan Green <evgreen@chromium.org>
> + * and January 2020 by Daniel Campello <campello@chromium.org>
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/pm.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/events.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/triggered_buffer.h>
> +#include <linux/iio/trigger_consumer.h>
> +
> +/* Register definitions. */
> +#define SX9310_REG_IRQ_SRC				0x00
> +#define SX9310_REG_STAT0				0x01
> +#define SX9310_REG_STAT1				0x02
> +#define SX9310_REG_IRQ_MSK				0x03
> +#define   SX9310_CONVDONE_IRQ				BIT(3)
> +#define   SX9310_FAR_IRQ				BIT(5)
> +#define   SX9310_CLOSE_IRQ				BIT(6)
> +#define   SX9310_EVENT_IRQ				(SX9310_FAR_IRQ | \
> +							 SX9310_CLOSE_IRQ)
> +#define SX9310_REG_IRQ_FUNC				0x04
> +
> +#define SX9310_REG_PROX_CTRL0				0x10
> +#define   SX9310_REG_PROX_CTRL0_PROXSTAT2		0x10
> +#define   SX9310_REG_PROX_CTRL0_EN_MASK			0x0F
> +#define SX9310_REG_PROX_CTRL1				0x11
> +#define SX9310_REG_PROX_CTRL2				0x12
> +#define   SX9310_REG_PROX_CTRL2_COMBMODE_ALL		0x80
> +#define   SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC	0x04
> +#define SX9310_REG_PROX_CTRL3				0x13
> +#define   SX9310_REG_PROX_CTRL3_GAIN0_X8		0x0c
> +#define   SX9310_REG_PROX_CTRL3_GAIN12_X4		0x02
> +#define SX9310_REG_PROX_CTRL4				0x14
> +#define   SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST	0x07
> +#define SX9310_REG_PROX_CTRL5				0x15
> +#define   SX9310_REG_PROX_CTRL5_RANGE_SMALL		0xc0
> +#define   SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1		0x04
> +#define   SX9310_REG_PROX_CTRL5_RAWFILT_1P25		0x02
> +#define SX9310_REG_PROX_CTRL6				0x16
> +#define   SX9310_REG_PROX_CTRL6_COMP_COMMON		0x20
> +#define SX9310_REG_PROX_CTRL7				0x17
> +#define   SX9310_REG_PROX_CTRL7_AVGNEGFILT_2		0x08
> +#define   SX9310_REG_PROX_CTRL7_AVGPOSFILT_512		0x05
> +#define SX9310_REG_PROX_CTRL8				0x18
> +#define SX9310_REG_PROX_CTRL9				0x19
> +#define   SX9310_REG_PROX_CTRL8_9_PTHRESH12_28		0x40
> +#define   SX9310_REG_PROX_CTRL8_9_PTHRESH_96		0x88
> +#define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900	0x03
> +#define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500	0x05
> +#define SX9310_REG_PROX_CTRL10				0x1a
> +#define   SX9310_REG_PROX_CTRL10_HYST_6PCT		0x10
> +#define   SX9310_REG_PROX_CTRL10_CLOSE_DEBOUNCE_8	0x12
> +#define   SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_8		0x03
> +#define SX9310_REG_PROX_CTRL11				0x1b
> +#define SX9310_REG_PROX_CTRL12				0x1c
> +#define SX9310_REG_PROX_CTRL13				0x1d
> +#define SX9310_REG_PROX_CTRL14				0x1e
> +#define SX9310_REG_PROX_CTRL15				0x1f
> +#define SX9310_REG_PROX_CTRL16				0x20
> +#define SX9310_REG_PROX_CTRL17				0x21
> +#define SX9310_REG_PROX_CTRL18				0x22
> +#define SX9310_REG_PROX_CTRL19				0x23
> +#define SX9310_REG_SAR_CTRL0				0x2a
> +#define   SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES		0x40
> +#define   SX9310_REG_SAR_CTRL0_SARHYST_8		0x10
> +#define SX9310_REG_SAR_CTRL1				0x2b
> +/* Each increment of the slope register is 0.0078125. */
> +#define   SX9310_REG_SAR_CTRL1_SLOPE(_hnslope)		(_hnslope / 78125)
> +#define SX9310_REG_SAR_CTRL2				0x2c
> +#define   SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT	0x3c
> +
> +#define SX9310_REG_SENSOR_SEL				0x30
> +
> +#define SX9310_REG_USE_MSB				0x31
> +#define SX9310_REG_USE_LSB				0x32
> +
> +#define SX9310_REG_AVG_MSB				0x33
> +#define SX9310_REG_AVG_LSB				0x34
> +
> +#define SX9310_REG_DIFF_MSB				0x35
> +#define SX9310_REG_DIFF_LSB				0x36
> +
> +#define SX9310_REG_OFFSET_MSB				0x37
> +#define SX9310_REG_OFFSET_LSB				0x38
> +
> +#define SX9310_REG_SAR_MSB				0x39
> +#define SX9310_REG_SAR_LSB				0x3a
> +
> +#define SX9310_REG_I2CADDR				0x40
> +#define SX9310_REG_PAUSE				0x41
> +#define SX9310_REG_WHOAMI				0x42
> +#define   SX9310_WHOAMI_VALUE				0x01
> +#define   SX9311_WHOAMI_VALUE				0x02
> +
> +#define SX9310_REG_RESET				0x7f
> +#define   SX9310_SOFT_RESET				0xde
> +
> +#define SX9310_SCAN_PERIOD_MASK				GENMASK(7, 4)
> +#define SX9310_SCAN_PERIOD_SHIFT			4
> +
> +#define SX9310_COMPSTAT_MASK				GENMASK(3, 0)
> +
> +/* 4 hardware channels, as defined in STAT0: COMB, CS2, CS1 and CS0. */
> +#define SX9310_NUM_CHANNELS				4
> +#define SX9310_HW_CHAN_MASK				GENMASK(1, 0)
> +#define SX9310_CHAN_ENABLED_MASK			GENMASK(3, 0)
> +
> +struct sx9310_data {
> +	/* Serialize access to registers and channel configuration */
> +	struct mutex mutex;
> +	struct i2c_client *client;
> +	struct iio_trigger *trig;
> +	struct regmap *regmap;
> +	/*
> +	 * Last reading of the proximity status for each channel.
> +	 * We only send an event to user space when this changes.
> +	 */
> +	bool prox_stat[SX9310_NUM_CHANNELS];
> +	bool trigger_enabled;
> +	__be16 *buffer;
> +	/* Remember enabled channels and sample rate during suspend. */
> +	unsigned int suspend_ctrl0;
> +	struct completion completion;
> +	unsigned int chan_read, chan_event;
> +	int channel_users[SX9310_NUM_CHANNELS];
> +	int whoami;
> +};
> +
> +static const struct iio_event_spec sx9310_events[] = {
> +	{
> +		.type = IIO_EV_TYPE_THRESH,
> +		.dir = IIO_EV_DIR_EITHER,
> +		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
> +	},
> +};
> +
> +#define SX9310_CHANNEL(idx)						 \
> +	{								 \
> +		.type = IIO_PROXIMITY,					 \
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		 \
> +		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> +		.indexed = 1,						 \
> +		.channel = idx,						 \
> +		.address = SX9310_REG_USE_MSB,				 \
> +		.event_spec = sx9310_events,				 \
> +		.num_event_specs = ARRAY_SIZE(sx9310_events),		 \
> +		.scan_index = idx,					 \
> +		.scan_type = {						 \
> +			.sign = 's',					 \
> +			.realbits = 16,					 \
> +			.storagebits = 16,				 \
> +			.endianness = IIO_BE,				 \
> +		},							 \
> +	}
> +
> +#define SX9310_DIFF_CHANNEL(idx)					 \
> +	{								 \
> +		.type = IIO_PROXIMITY,					 \
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		 \
> +		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> +		.indexed = 1,						 \
> +		.channel = idx & SX9310_HW_CHAN_MASK,			 \
> +		.channel2 = idx & SX9310_HW_CHAN_MASK,			 \
> +		.address = SX9310_REG_DIFF_MSB,				 \
> +		.scan_index = idx,					 \
> +		.scan_type = {						 \
> +			.sign = 's',					 \
> +			.realbits = 12,					 \
> +			.storagebits = 16,				 \
> +			.endianness = IIO_BE,				 \
> +		},							 \
> +		.differential = 1,					 \
> +	}
> +
> +static const struct iio_chan_spec sx9310_channels[] = {
> +	SX9310_CHANNEL(0), /* USE_CS0 */
> +	SX9310_CHANNEL(1), /* USE_CS1 */
> +	SX9310_CHANNEL(2), /* USE_CS2 */
> +	SX9310_CHANNEL(3), /* USE_COMB */
> +
> +	SX9310_DIFF_CHANNEL(4), /* DIFF_CS0 */
> +	SX9310_DIFF_CHANNEL(5), /* DIFF_CS1 */
> +	SX9310_DIFF_CHANNEL(6), /* DIFF_CS2 */
> +	SX9310_DIFF_CHANNEL(7), /* DIFF_COMB */
> +
> +	IIO_CHAN_SOFT_TIMESTAMP(8),
> +};
> +
> +/*
> + * Each entry contains the integer part (val) and the fractional part, in micro
> + * seconds. It conforms to the IIO output IIO_VAL_INT_PLUS_MICRO.
> + */
> +static const struct {
> +	int val;
> +	int val2;
> +} sx9310_samp_freq_table[] = {
> +	{ 500, 0 }, /* 0000: Min (no idle time) */
> +	{ 66, 666666 }, /* 0001: 15 ms */
> +	{ 33, 333333 }, /* 0010: 30 ms (Typ.) */
> +	{ 22, 222222 }, /* 0011: 45 ms */
> +	{ 16, 666666 }, /* 0100: 60 ms */
> +	{ 11, 111111 }, /* 0101: 90 ms */
> +	{ 8, 333333 }, /* 0110: 120 ms */
> +	{ 5, 0 }, /* 0111: 200 ms */
> +	{ 2, 500000 }, /* 1000: 400 ms */
> +	{ 1, 666666 }, /* 1001: 600 ms */
> +	{ 1, 250000 }, /* 1010: 800 ms */
> +	{ 1, 0 }, /* 1011: 1 s */
> +	{ 0, 500000 }, /* 1100: 2 s */
> +	{ 0, 333333 }, /* 1101: 3 s */
> +	{ 0, 250000 }, /* 1110: 4 s */
> +	{ 0, 200000 }, /* 1111: 5 s */
> +};
> +static const unsigned int sx9310_scan_period_table[] = {
> +	2,   15,  30,  45,   60,   90,	 120,  200,
> +	400, 600, 800, 1000, 2000, 3000, 4000, 5000,
> +};
> +
> +static ssize_t sx9310_show_samp_freq_avail(struct device *dev,
> +					   struct device_attribute *attr,
> +					   char *buf)
> +{
> +	size_t len = 0;
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
> +		len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%d ",
> +				 sx9310_samp_freq_table[i].val,
> +				 sx9310_samp_freq_table[i].val2);
> +	buf[len - 1] = '\n';
> +	return len;
> +}
> +static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sx9310_show_samp_freq_avail);
> +
> +static const struct regmap_range sx9310_writable_reg_ranges[] = {
> +	regmap_reg_range(SX9310_REG_IRQ_MSK, SX9310_REG_IRQ_FUNC),
> +	regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
> +	regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
> +	regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SENSOR_SEL),
> +	regmap_reg_range(SX9310_REG_OFFSET_MSB, SX9310_REG_OFFSET_LSB),
> +	regmap_reg_range(SX9310_REG_PAUSE, SX9310_REG_PAUSE),
> +	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
> +};
> +
> +static const struct regmap_access_table sx9310_writeable_regs = {
> +	.yes_ranges = sx9310_writable_reg_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(sx9310_writable_reg_ranges),
> +};
> +
> +static const struct regmap_range sx9310_readable_reg_ranges[] = {
> +	regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_IRQ_FUNC),
> +	regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
> +	regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
> +	regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SAR_LSB),
> +	regmap_reg_range(SX9310_REG_I2CADDR, SX9310_REG_WHOAMI),
> +	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
> +};
> +
> +static const struct regmap_access_table sx9310_readable_regs = {
> +	.yes_ranges = sx9310_readable_reg_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(sx9310_readable_reg_ranges),
> +};
> +
> +static const struct regmap_range sx9310_volatile_reg_ranges[] = {
> +	regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_STAT1),
> +	regmap_reg_range(SX9310_REG_USE_MSB, SX9310_REG_DIFF_LSB),
> +	regmap_reg_range(SX9310_REG_SAR_MSB, SX9310_REG_SAR_LSB),
> +	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
> +};
> +
> +static const struct regmap_access_table sx9310_volatile_regs = {
> +	.yes_ranges = sx9310_volatile_reg_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(sx9310_volatile_reg_ranges),
> +};
> +
> +static const struct regmap_config sx9310_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +
> +	.max_register = SX9310_REG_RESET,
> +	.cache_type = REGCACHE_RBTREE,
> +
> +	.wr_table = &sx9310_writeable_regs,
> +	.rd_table = &sx9310_readable_regs,
> +	.volatile_table = &sx9310_volatile_regs,
> +};
> +
> +static int sx9310_update_chan_en(struct sx9310_data *data,
> +				 unsigned int chan_read,
> +				 unsigned int chan_event)
> +{
> +	int ret = 0;

Value never used.

> +
> +	if ((data->chan_read | data->chan_event) != (chan_read | chan_event)) {
> +		ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
> +					 SX9310_CHAN_ENABLED_MASK,
> +					 chan_read | chan_event);
> +		if (ret)
> +			return ret;
> +	}
> +	data->chan_read = chan_read;
> +	data->chan_event = chan_event;
> +	return 0;
> +}
> +
> +static int sx9310_get_read_channel(struct sx9310_data *data, int channel)
> +{
> +	return sx9310_update_chan_en(data, data->chan_read | BIT(channel),
> +				     data->chan_event);
> +}
> +
> +static int sx9310_put_read_channel(struct sx9310_data *data, int channel)
> +{
> +	return sx9310_update_chan_en(data, data->chan_read & ~BIT(channel),
> +				     data->chan_event);
> +}
> +
> +static int sx9310_get_event_channel(struct sx9310_data *data, int channel)
> +{
> +	return sx9310_update_chan_en(data, data->chan_read,
> +				     data->chan_event | BIT(channel));
> +}
> +
> +static int sx9310_put_event_channel(struct sx9310_data *data, int channel)
> +{
> +	return sx9310_update_chan_en(data, data->chan_read,
> +				     data->chan_event & ~BIT(channel));
> +}
> +
> +static int sx9310_enable_irq(struct sx9310_data *data, unsigned int irq)
> +{
> +	return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, irq);
> +}
> +
> +static int sx9310_disable_irq(struct sx9310_data *data, unsigned int irq)
> +{
> +	return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, 0);
> +}
> +
> +static int sx9310_read_prox_data(struct sx9310_data *data,
> +				 const struct iio_chan_spec *chan, __be16 *val)
> +{
> +	int ret;
> +
> +	ret = regmap_write(data->regmap, SX9310_REG_SENSOR_SEL, chan->channel);
> +	if (ret < 0)
> +		return ret;
> +
> +	return regmap_bulk_read(data->regmap, chan->address, val, 2);
> +}
> +
> +/*
> + * If we have no interrupt support, we have to wait for a scan period
> + * after enabling a channel to get a result.
> + */
> +static int sx9310_wait_for_sample(struct sx9310_data *data)
> +{
> +	int ret;
> +	unsigned int val;
> +
> +	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	val = (val & SX9310_SCAN_PERIOD_MASK) >> SX9310_SCAN_PERIOD_SHIFT;
> +
> +	msleep(sx9310_scan_period_table[val]);
> +
> +	return 0;
> +}
> +
> +static int sx9310_read_proximity(struct sx9310_data *data,
> +				 const struct iio_chan_spec *chan, int *val)
> +{
> +	int ret = 0;
> +	__be16 rawval;
> +
> +	mutex_lock(&data->mutex);
> +
> +	ret = sx9310_get_read_channel(data, chan->channel);
> +	if (ret < 0)
> +		goto out;
> +
> +	if (!data->trigger_enabled) {

I'm fairly sure you can't get here with the trigger enabled.  You
have claimed direct mode.  That can't succeed if triggered buffer
capture is enabled.

> +		ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
> +		if (ret < 0)
> +			goto out_put_channel;
> +	}
> +
> +	mutex_unlock(&data->mutex);
> +
> +	if (data->client->irq > 0) {
> +		ret = wait_for_completion_interruptible(&data->completion);
> +		reinit_completion(&data->completion);
> +	} else {
> +		ret = sx9310_wait_for_sample(data);
> +	}
> +
> +	mutex_lock(&data->mutex);
> +
> +	if (ret < 0)
> +		goto out_disable_irq;
> +
> +	ret = sx9310_read_prox_data(data, chan, &rawval);
> +	if (ret < 0)
> +		goto out_disable_irq;
> +
> +	*val = sign_extend32(be16_to_cpu(rawval),
> +			     (chan->address == SX9310_REG_DIFF_MSB ? 11 : 15));
> +
> +	if (!data->trigger_enabled) {
> +		ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
> +		if (ret < 0)
> +			goto out_put_channel;
> +	}
> +
> +	ret = sx9310_put_read_channel(data, chan->channel);
> +	if (ret < 0)
> +		goto out;
> +
> +	mutex_unlock(&data->mutex);
> +
> +	return IIO_VAL_INT;
> +
> +out_disable_irq:
> +	if (!data->trigger_enabled)
> +		sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
> +out_put_channel:
> +	sx9310_put_read_channel(data, chan->channel);
> +out:
> +	mutex_unlock(&data->mutex);
> +
> +	return ret;
> +}
> +
> +static int sx9310_read_samp_freq(struct sx9310_data *data, int *val, int *val2)
> +{
> +	unsigned int regval;
> +	int ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &regval);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	regval = (regval & SX9310_SCAN_PERIOD_MASK) >> SX9310_SCAN_PERIOD_SHIFT;
> +	*val = sx9310_samp_freq_table[regval].val;
> +	*val2 = sx9310_samp_freq_table[regval].val2;
> +
> +	return IIO_VAL_INT_PLUS_MICRO;
> +}
> +
> +static int sx9310_read_raw(struct iio_dev *indio_dev,
> +			   const struct iio_chan_spec *chan, int *val,
> +			   int *val2, long mask)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	if (chan->type != IIO_PROXIMITY)
> +		return -EINVAL;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		ret = iio_device_claim_direct_mode(indio_dev);
> +		if (ret)
> +			return ret;
> +
> +		ret = sx9310_read_proximity(data, chan, val);
> +		iio_device_release_direct_mode(indio_dev);
> +		return ret;
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		return sx9310_read_samp_freq(data, val, val2);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int sx9310_set_samp_freq(struct sx9310_data *data, int val, int val2)
> +{
> +	int i, ret;
> +
> +	for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
> +		if (val == sx9310_samp_freq_table[i].val &&
> +		    val2 == sx9310_samp_freq_table[i].val2)
> +			break;
> +
> +	if (i == ARRAY_SIZE(sx9310_samp_freq_table))
> +		return -EINVAL;
> +
> +	mutex_lock(&data->mutex);
> +
> +	ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
> +				 SX9310_SCAN_PERIOD_MASK,
> +				 i << SX9310_SCAN_PERIOD_SHIFT);
> +
> +	mutex_unlock(&data->mutex);
> +
> +	return ret;
> +}
> +
> +static int sx9310_write_raw(struct iio_dev *indio_dev,
> +			    const struct iio_chan_spec *chan, int val, int val2,
> +			    long mask)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +
> +	if (chan->type != IIO_PROXIMITY)
> +		return -EINVAL;
> +
> +	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
> +		return -EINVAL;
> +
> +	return sx9310_set_samp_freq(data, val, val2);
> +}
> +
> +static irqreturn_t sx9310_irq_handler(int irq, void *private)
> +{
> +	struct iio_dev *indio_dev = private;
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +
> +	if (data->trigger_enabled)
> +		iio_trigger_poll(data->trig);
> +
> +	/*
> +	 * Even if no event is enabled, we need to wake the thread to
> +	 * clear the interrupt state by reading SX9310_REG_IRQ_SRC.  It
> +	 * is not possible to do that here because regmap_read takes a
> +	 * mutex.
> +	 */
> +	return IRQ_WAKE_THREAD;
> +}
> +
> +static void sx9310_push_events(struct iio_dev *indio_dev)
> +{
> +	int ret;
> +	unsigned int val, chan;
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	s64 timestamp = iio_get_time_ns(indio_dev);
> +
> +	/* Read proximity state on all channels */
> +	ret = regmap_read(data->regmap, SX9310_REG_STAT0, &val);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "i2c transfer error in irq\n");
> +		return;
> +	}
> +
> +	for (chan = 0; chan < SX9310_NUM_CHANNELS; chan++) {
> +		int dir;
> +		u64 ev;
> +		bool new_prox = val & BIT(chan);
> +
> +		if (!(data->chan_event & BIT(chan)))
> +			continue;
> +		if (new_prox == data->prox_stat[chan])
> +			/* No change on this channel. */
> +			continue;
> +
> +		dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
> +		ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
> +					  IIO_EV_TYPE_THRESH, dir);
> +
> +		iio_push_event(indio_dev, ev, timestamp);
> +		data->prox_stat[chan] = new_prox;
> +	}
> +}
> +
> +static irqreturn_t sx9310_irq_thread_handler(int irq, void *private)
> +{
> +	struct iio_dev *indio_dev = private;
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret;
> +	unsigned int val;
> +
> +	mutex_lock(&data->mutex);
> +
> +	ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "i2c transfer error in irq\n");
> +		goto out;
> +	}
> +
> +	if (val & (SX9310_EVENT_IRQ))

Too many brackets.

> +		sx9310_push_events(indio_dev);
> +
> +	if (val & SX9310_CONVDONE_IRQ)
> +		complete(&data->completion);
> +
> +out:
> +	mutex_unlock(&data->mutex);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int sx9310_read_event_config(struct iio_dev *indio_dev,
> +				    const struct iio_chan_spec *chan,
> +				    enum iio_event_type type,
> +				    enum iio_event_direction dir)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +
> +	return !!(data->chan_event & BIT(chan->channel));
> +}
> +
> +static int sx9310_write_event_config(struct iio_dev *indio_dev,
> +				     const struct iio_chan_spec *chan,
> +				     enum iio_event_type type,
> +				     enum iio_event_direction dir, int state)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret = 0;
> +
> +	/* If the state hasn't changed, there's nothing to do. */
> +	if (!!(data->chan_event & BIT(chan->channel)) == state)
> +		return 0;
> +
> +	mutex_lock(&data->mutex);
> +	if (state) {
> +		ret = sx9310_get_event_channel(data, chan->channel);
> +		if (ret < 0)
> +			goto out_unlock;
> +		if (!(data->chan_event & ~BIT(chan->channel))) {
> +			ret = sx9310_enable_irq(data, SX9310_EVENT_IRQ);
> +			if (ret < 0)
> +				sx9310_put_event_channel(data, chan->channel);
> +		}
> +	} else {
> +		ret = sx9310_put_event_channel(data, chan->channel);
> +		if (ret < 0)
> +			goto out_unlock;
> +		if (!data->chan_event) {
> +			ret = sx9310_disable_irq(data, SX9310_EVENT_IRQ);
> +			if (ret < 0)
> +				sx9310_get_event_channel(data, chan->channel);
> +		}
> +	}
> +
> +out_unlock:
> +	mutex_unlock(&data->mutex);
> +	return ret;
> +}
> +
> +static int sx9310_update_scan_mode(struct iio_dev *indio_dev,
> +				   const unsigned long *scan_mask)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +
> +	mutex_lock(&data->mutex);
> +	kfree(data->buffer);
> +	data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);

Seems unlikely to me that this actually varies enough to make dynamic
resizing worth doing.  I would just put a suitably big fixed
size array in data in the first place.

There is a reasonable chance that will not need any more memory at all
and if it does it won't be worse than what you have here.

> +	mutex_unlock(&data->mutex);
> +
> +	if (data->buffer == NULL)
> +		return -ENOMEM;
> +
> +	return 0;
> +}
> +
> +static struct attribute *sx9310_attributes[] = {
> +	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group sx9310_attribute_group = {
> +	.attrs = sx9310_attributes,
> +};
> +
> +static const struct iio_info sx9310_info = {
> +	.attrs = &sx9310_attribute_group,
> +	.read_raw = sx9310_read_raw,
> +	.write_raw = sx9310_write_raw,
> +	.read_event_config = sx9310_read_event_config,
> +	.write_event_config = sx9310_write_event_config,
> +	.update_scan_mode = sx9310_update_scan_mode,
> +};
> +
> +static int sx9310_set_trigger_state(struct iio_trigger *trig, bool state)
> +{
> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret = 0;
> +
> +	mutex_lock(&data->mutex);
> +
> +	if (state)
> +		ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
> +	else if (!data->chan_read)
> +		ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
> +	if (ret < 0)
> +		goto out;
> +
> +	data->trigger_enabled = state;
> +
> +out:
> +	mutex_unlock(&data->mutex);
> +
> +	return ret;
> +}
> +
> +static const struct iio_trigger_ops sx9310_trigger_ops = {
> +	.set_trigger_state = sx9310_set_trigger_state,
> +};
> +
> +static irqreturn_t sx9310_trigger_handler(int irq, void *private)
> +{
> +	struct iio_poll_func *pf = private;
> +	struct iio_dev *indio_dev = pf->indio_dev;
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	__be16 val;
> +	int bit, ret, i = 0;
> +
> +	mutex_lock(&data->mutex);
> +
> +	for_each_set_bit(bit, indio_dev->active_scan_mask,
> +			 indio_dev->masklength) {
> +		ret = sx9310_read_prox_data(data, &indio_dev->channels[bit],
> +					    &val);
> +		if (ret < 0)
> +			goto out;
> +
> +		data->buffer[i++] = val;
> +	}
> +
> +	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
> +					   pf->timestamp);
> +
> +out:
> +	mutex_unlock(&data->mutex);
> +
> +	iio_trigger_notify_done(indio_dev->trig);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int sx9310_buffer_preenable(struct iio_dev *indio_dev)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	unsigned int channels = 0;
> +	int bit, ret;
> +
> +	mutex_lock(&data->mutex);
> +	for_each_set_bit(bit, indio_dev->active_scan_mask,
> +			 indio_dev->masklength)
> +		channels |= BIT(indio_dev->channels[bit].channel);
> +
> +	ret = sx9310_update_chan_en(data, channels, data->chan_event);
> +	mutex_unlock(&data->mutex);
> +	return ret;
> +}
> +
> +static int sx9310_buffer_postdisable(struct iio_dev *indio_dev)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	mutex_lock(&data->mutex);
> +	ret = sx9310_update_chan_en(data, 0, data->chan_event);
> +	mutex_unlock(&data->mutex);
> +	return ret;
> +}
> +
> +static const struct iio_buffer_setup_ops sx9310_buffer_setup_ops = {
> +	.preenable = sx9310_buffer_preenable,
> +	.postenable = iio_triggered_buffer_postenable,
> +	.predisable = iio_triggered_buffer_predisable,
> +	.postdisable = sx9310_buffer_postdisable,
> +};
> +
> +struct sx9310_reg_default {
> +	u8 reg;
> +	u8 def;
> +};
> +
> +#define SX_INIT(_reg, _def)			\
> +	{					\
> +		.reg = SX9310_REG_##_reg,	\
> +		.def = _def,			\
> +	}
> +
> +static const struct sx9310_reg_default sx9310_default_regs[] = {
> +	SX_INIT(IRQ_MSK, 0x00),
> +	SX_INIT(IRQ_FUNC, 0x00),
> +	/*
> +	 * The lower 4 bits should not be set as it enable sensors measurements.
> +	 * Turning the detection on before the configuration values are set to
> +	 * good values can cause the device to return erroneous readings.
> +	 */
> +	SX_INIT(PROX_CTRL0, SX9310_REG_PROX_CTRL0_PROXSTAT2),
> +	SX_INIT(PROX_CTRL1, 0x00),
> +	SX_INIT(PROX_CTRL2, SX9310_REG_PROX_CTRL2_COMBMODE_ALL |
> +			    SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC),
> +	SX_INIT(PROX_CTRL3, SX9310_REG_PROX_CTRL3_GAIN0_X8 |
> +			    SX9310_REG_PROX_CTRL3_GAIN12_X4),
> +	SX_INIT(PROX_CTRL4, SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST),
> +	SX_INIT(PROX_CTRL5, SX9310_REG_PROX_CTRL5_RANGE_SMALL |
> +			    SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1 |
> +			    SX9310_REG_PROX_CTRL5_RAWFILT_1P25),
> +	SX_INIT(PROX_CTRL6, SX9310_REG_PROX_CTRL6_COMP_COMMON),
> +	SX_INIT(PROX_CTRL7, SX9310_REG_PROX_CTRL7_AVGNEGFILT_2 |
> +			    SX9310_REG_PROX_CTRL7_AVGPOSFILT_512),
> +	SX_INIT(PROX_CTRL8, SX9310_REG_PROX_CTRL8_9_PTHRESH_96 |
> +			    SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500),
> +	SX_INIT(PROX_CTRL9, SX9310_REG_PROX_CTRL8_9_PTHRESH12_28 |
> +			    SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900),
> +	SX_INIT(PROX_CTRL10, SX9310_REG_PROX_CTRL10_HYST_6PCT |
> +			     SX9310_REG_PROX_CTRL10_CLOSE_DEBOUNCE_8 |
> +			     SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_8),
> +	SX_INIT(PROX_CTRL11, 0x00),
> +	SX_INIT(PROX_CTRL12, 0x00),
> +	SX_INIT(PROX_CTRL13, 0x00),
> +	SX_INIT(PROX_CTRL14, 0x00),
> +	SX_INIT(PROX_CTRL15, 0x00),
> +	SX_INIT(PROX_CTRL16, 0x00),
> +	SX_INIT(PROX_CTRL17, 0x00),
> +	SX_INIT(PROX_CTRL18, 0x00),
> +	SX_INIT(PROX_CTRL19, 0x00),
> +	SX_INIT(SAR_CTRL0, SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES |
> +			   SX9310_REG_SAR_CTRL0_SARHYST_8),
> +	SX_INIT(SAR_CTRL1, SX9310_REG_SAR_CTRL1_SLOPE(10781250)),
> +	SX_INIT(SAR_CTRL2, SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT),
> +};
> +
> +/* Activate all channels and perform an initial compensation. */
> +static int sx9310_init_compensation(struct iio_dev *indio_dev)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int i, ret;
> +	unsigned int val;
> +	unsigned int ctrl0;
> +
> +	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &ctrl0);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* run the compensation phase on all channels */
> +	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
> +			   ctrl0 | SX9310_REG_PROX_CTRL0_EN_MASK);
> +	if (ret < 0)
> +		return ret;
> +
> +	for (i = 100; i >= 0; i--) {
> +		msleep(20);
> +		ret = regmap_read(data->regmap, SX9310_REG_STAT1, &val);
> +		if (ret < 0)
> +			goto out;
> +		if (!(val & SX9310_COMPSTAT_MASK))
> +			break;
> +	}
> +
> +	if (i < 0) {
> +		dev_err(&data->client->dev,
> +			"initial compensation timed out: 0x%02x", val);
> +		ret = -ETIMEDOUT;
> +	}
> +
> +out:
> +	regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
> +	return ret;
> +}
> +
> +static int sx9310_init_device(struct iio_dev *indio_dev)
> +{
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	const struct sx9310_reg_default *initval;
> +	int ret;
> +	unsigned int i, val;
> +
> +	/* Soft reset the device. */
As this is obvious from the code, the comment is just something that might
rot in the future. I'd rather we had no comment on this one.

> +	ret = regmap_write(data->regmap, SX9310_REG_RESET, SX9310_SOFT_RESET);
> +	if (ret < 0)
> +		return ret;
> +
> +	usleep_range(1000, 2000); /* power-up time is ~1ms. */
> +
> +	/* Clear reset interrupt state by reading SX9310_REG_IRQ_SRC. */
> +	ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Program some sane defaults. */
> +	for (i = 0; i < ARRAY_SIZE(sx9310_default_regs); i++) {
> +		initval = &sx9310_default_regs[i];
> +		ret = regmap_write(data->regmap, initval->reg, initval->def);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return sx9310_init_compensation(indio_dev);
> +}
> +
> +static int sx9310_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	int ret;
> +	struct iio_dev *indio_dev;
> +	struct sx9310_data *data;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (indio_dev == NULL)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	data->client = client;
> +	mutex_init(&data->mutex);
> +	init_completion(&data->completion);
> +
> +	data->regmap = devm_regmap_init_i2c(client, &sx9310_regmap_config);
> +	if (IS_ERR(data->regmap))
> +		return PTR_ERR(data->regmap);
> +
> +	ret = regmap_read(data->regmap, SX9310_REG_WHOAMI, &data->whoami);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "error in reading WHOAMI register: %d",
> +			ret);
> +		return ret;
> +	}
> +	switch (data->whoami) {
> +	case SX9310_WHOAMI_VALUE:

You should also verify that this matches the expected device type.
By all means just give a warning if it doesn't and carry on though.

> +		indio_dev->name = "sx9310";
> +		break;
> +	case SX9311_WHOAMI_VALUE:
> +		indio_dev->name = "sx9311";
> +		break;
> +	default:
> +		dev_err(&client->dev, "unexpected WHOAMI response: %u",
> +			data->whoami);
> +		return -ENODEV;
> +	}
> +
> +	ACPI_COMPANION_SET(&indio_dev->dev, ACPI_COMPANION(&client->dev));
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->channels = sx9310_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(sx9310_channels);
> +	indio_dev->info = &sx9310_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	i2c_set_clientdata(client, indio_dev);
> +
> +	ret = sx9310_init_device(indio_dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (client->irq >= 0) {

client->irq == 0 means no irq.

> +		ret = devm_request_threaded_irq(&client->dev, client->irq,
> +						sx9310_irq_handler,
> +						sx9310_irq_thread_handler,
> +						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> +						"sx9310_event", indio_dev);
> +		if (ret < 0)
> +			return ret;
> +
> +		data->trig =
> +			devm_iio_trigger_alloc(&client->dev, "%s-dev%d",
> +					       indio_dev->name, indio_dev->id);
> +		if (!data->trig)
> +			return -ENOMEM;
> +
> +		data->trig->dev.parent = &client->dev;
> +		data->trig->ops = &sx9310_trigger_ops;
> +		iio_trigger_set_drvdata(data->trig, indio_dev);
> +
> +		ret = devm_iio_trigger_register(&client->dev, data->trig);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
> +					      iio_pollfunc_store_time,
> +					      sx9310_trigger_handler,
> +					      &sx9310_buffer_setup_ops);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = devm_iio_device_register(&client->dev, indio_dev);
return devm...

> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int sx9310_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +
> +	kfree(data->buffer);
Hmm. This results in us removing the buffer before the interfaces
that might lead to it being used are unregistered. 

> +	return 0;
> +}
> +
> +static int __maybe_unused sx9310_suspend(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	u8 ctrl0;
> +	int ret;
> +
> +	disable_irq_nosync(data->client->irq);
> +
> +	mutex_lock(&data->mutex);
> +	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0,
> +			  &data->suspend_ctrl0);
> +
> +	if (ret)
> +		goto out;
> +
> +	ctrl0 = data->suspend_ctrl0 & ~SX9310_REG_PROX_CTRL0_EN_MASK;
> +	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
> +	if (ret)
> +		goto out;
> +
> +	ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 0);
> +
> +out:
> +	mutex_unlock(&data->mutex);
> +	return ret;
> +}
> +
> +static int __maybe_unused sx9310_resume(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct sx9310_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	mutex_lock(&data->mutex);
> +	ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 1);
> +	if (ret)
> +		goto out;
> +
> +	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
> +			   data->suspend_ctrl0);
> +
> +out:
> +	mutex_unlock(&data->mutex);
> +
> +	enable_irq(data->client->irq);
> +
> +	return ret;
> +}
> +
> +static const struct dev_pm_ops sx9310_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(sx9310_suspend, sx9310_resume)
> +};
> +
> +static const struct acpi_device_id sx9310_acpi_match[] = {
> +	{ "STH9310", 0 },

I'm getting more paranoid on these.  Does semtech have a public
list of what they have allocated somewhere? 
I guess you have these live in a firmware though so we'll need
to support them either way.

> +	{ "STH9311", 0 },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(acpi, sx9310_acpi_match);
> +
> +static const struct of_device_id sx9310_of_match[] = {
> +	{ .compatible = "semtech,sx9310" },
> +	{ .compatible = "semtech,sx9311" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, sx9310_of_match);
> +
> +static const struct i2c_device_id sx9310_id[] = {
> +	{ "sx9310", 0 },
> +	{ "sx9311", 0 },

No point in specifying the data field if they are all going to be 0.

> +	{},
> +};
> +MODULE_DEVICE_TABLE(i2c, sx9310_id);
> +
> +static struct i2c_driver sx9310_driver = {
> +	.driver = {
> +		.name	= "sx9310",
> +		.acpi_match_table = ACPI_PTR(sx9310_acpi_match),
> +		.of_match_table = of_match_ptr(sx9310_of_match),
> +		.pm = &sx9310_pm_ops,
> +	},
> +	.probe		= sx9310_probe,
> +	.remove		= sx9310_remove,
> +	.id_table	= sx9310_id,
> +};
> +module_i2c_driver(sx9310_driver);
> +
> +MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
> +MODULE_AUTHOR("Daniel Campello <campello@chromium.org>");
> +MODULE_DESCRIPTION("Driver for Semtech SX9310/SX9311 proximity sensor");
> +MODULE_LICENSE("GPL v2");
> --
> 2.25.0.341.g760bfbb309-goog
>

Patch
diff mbox series

diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index d53601447da433..fd82962f2e3abc 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -86,6 +86,20 @@  config SRF04
 	  To compile this driver as a module, choose M here: the
 	  module will be called srf04.

+config SX9310
+	tristate "SX9310/SX9311 Semtech proximity sensor"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	select REGMAP_I2C
+	depends on I2C
+	depends on ACPI
+	help
+	  Say Y here to build a driver for Semtech's SX9310/SX9311 capacitive
+	  proximity/button sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called sx9310.
+
 config SX9500
 	tristate "SX9500 Semtech proximity sensor"
 	select IIO_BUFFER
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index 0bb5f9de13d657..b7ebd94a1bb6ed 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -11,6 +11,7 @@  obj-$(CONFIG_MB1232)		+= mb1232.o
 obj-$(CONFIG_RFD77402)		+= rfd77402.o
 obj-$(CONFIG_SRF04)		+= srf04.o
 obj-$(CONFIG_SRF08)		+= srf08.o
+obj-$(CONFIG_SX9310)		+= sx9310.o
 obj-$(CONFIG_SX9500)		+= sx9500.o
 obj-$(CONFIG_VL53L0X_I2C)	+= vl53l0x-i2c.o

diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c
new file mode 100644
index 00000000000000..427282cb26dbc5
--- /dev/null
+++ b/drivers/iio/proximity/sx9310.c
@@ -0,0 +1,1100 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018 Google LLC.
+ *
+ * Driver for Semtech's SX9310/SX9311 capacitive proximity/button solution.
+ * Based on SX9500 driver and Semtech driver using the input framework
+ * <https://my.syncplicity.com/share/teouwsim8niiaud/
+ *          linux-driver-SX9310_NoSmartHSensing>.
+ * Reworked April 2019 by Evan Green <evgreen@chromium.org>
+ * and January 2020 by Daniel Campello <campello@chromium.org>
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+/* Register definitions. */
+#define SX9310_REG_IRQ_SRC				0x00
+#define SX9310_REG_STAT0				0x01
+#define SX9310_REG_STAT1				0x02
+#define SX9310_REG_IRQ_MSK				0x03
+#define   SX9310_CONVDONE_IRQ				BIT(3)
+#define   SX9310_FAR_IRQ				BIT(5)
+#define   SX9310_CLOSE_IRQ				BIT(6)
+#define   SX9310_EVENT_IRQ				(SX9310_FAR_IRQ | \
+							 SX9310_CLOSE_IRQ)
+#define SX9310_REG_IRQ_FUNC				0x04
+
+#define SX9310_REG_PROX_CTRL0				0x10
+#define   SX9310_REG_PROX_CTRL0_PROXSTAT2		0x10
+#define   SX9310_REG_PROX_CTRL0_EN_MASK			0x0F
+#define SX9310_REG_PROX_CTRL1				0x11
+#define SX9310_REG_PROX_CTRL2				0x12
+#define   SX9310_REG_PROX_CTRL2_COMBMODE_ALL		0x80
+#define   SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC	0x04
+#define SX9310_REG_PROX_CTRL3				0x13
+#define   SX9310_REG_PROX_CTRL3_GAIN0_X8		0x0c
+#define   SX9310_REG_PROX_CTRL3_GAIN12_X4		0x02
+#define SX9310_REG_PROX_CTRL4				0x14
+#define   SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST	0x07
+#define SX9310_REG_PROX_CTRL5				0x15
+#define   SX9310_REG_PROX_CTRL5_RANGE_SMALL		0xc0
+#define   SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1		0x04
+#define   SX9310_REG_PROX_CTRL5_RAWFILT_1P25		0x02
+#define SX9310_REG_PROX_CTRL6				0x16
+#define   SX9310_REG_PROX_CTRL6_COMP_COMMON		0x20
+#define SX9310_REG_PROX_CTRL7				0x17
+#define   SX9310_REG_PROX_CTRL7_AVGNEGFILT_2		0x08
+#define   SX9310_REG_PROX_CTRL7_AVGPOSFILT_512		0x05
+#define SX9310_REG_PROX_CTRL8				0x18
+#define SX9310_REG_PROX_CTRL9				0x19
+#define   SX9310_REG_PROX_CTRL8_9_PTHRESH12_28		0x40
+#define   SX9310_REG_PROX_CTRL8_9_PTHRESH_96		0x88
+#define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900	0x03
+#define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500	0x05
+#define SX9310_REG_PROX_CTRL10				0x1a
+#define   SX9310_REG_PROX_CTRL10_HYST_6PCT		0x10
+#define   SX9310_REG_PROX_CTRL10_CLOSE_DEBOUNCE_8	0x12
+#define   SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_8		0x03
+#define SX9310_REG_PROX_CTRL11				0x1b
+#define SX9310_REG_PROX_CTRL12				0x1c
+#define SX9310_REG_PROX_CTRL13				0x1d
+#define SX9310_REG_PROX_CTRL14				0x1e
+#define SX9310_REG_PROX_CTRL15				0x1f
+#define SX9310_REG_PROX_CTRL16				0x20
+#define SX9310_REG_PROX_CTRL17				0x21
+#define SX9310_REG_PROX_CTRL18				0x22
+#define SX9310_REG_PROX_CTRL19				0x23
+#define SX9310_REG_SAR_CTRL0				0x2a
+#define   SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES		0x40
+#define   SX9310_REG_SAR_CTRL0_SARHYST_8		0x10
+#define SX9310_REG_SAR_CTRL1				0x2b
+/* Each increment of the slope register is 0.0078125. */
+#define   SX9310_REG_SAR_CTRL1_SLOPE(_hnslope)		(_hnslope / 78125)
+#define SX9310_REG_SAR_CTRL2				0x2c
+#define   SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT	0x3c
+
+#define SX9310_REG_SENSOR_SEL				0x30
+
+#define SX9310_REG_USE_MSB				0x31
+#define SX9310_REG_USE_LSB				0x32
+
+#define SX9310_REG_AVG_MSB				0x33
+#define SX9310_REG_AVG_LSB				0x34
+
+#define SX9310_REG_DIFF_MSB				0x35
+#define SX9310_REG_DIFF_LSB				0x36
+
+#define SX9310_REG_OFFSET_MSB				0x37
+#define SX9310_REG_OFFSET_LSB				0x38
+
+#define SX9310_REG_SAR_MSB				0x39
+#define SX9310_REG_SAR_LSB				0x3a
+
+#define SX9310_REG_I2CADDR				0x40
+#define SX9310_REG_PAUSE				0x41
+#define SX9310_REG_WHOAMI				0x42
+#define   SX9310_WHOAMI_VALUE				0x01
+#define   SX9311_WHOAMI_VALUE				0x02
+
+#define SX9310_REG_RESET				0x7f
+#define   SX9310_SOFT_RESET				0xde
+
+#define SX9310_SCAN_PERIOD_MASK				GENMASK(7, 4)
+#define SX9310_SCAN_PERIOD_SHIFT			4
+
+#define SX9310_COMPSTAT_MASK				GENMASK(3, 0)
+
+/* 4 hardware channels, as defined in STAT0: COMB, CS2, CS1 and CS0. */
+#define SX9310_NUM_CHANNELS				4
+#define SX9310_HW_CHAN_MASK				GENMASK(1, 0)
+#define SX9310_CHAN_ENABLED_MASK			GENMASK(3, 0)
+
+struct sx9310_data {
+	/* Serialize access to registers and channel configuration */
+	struct mutex mutex;
+	struct i2c_client *client;
+	struct iio_trigger *trig;
+	struct regmap *regmap;
+	/*
+	 * Last reading of the proximity status for each channel.
+	 * We only send an event to user space when this changes.
+	 */
+	bool prox_stat[SX9310_NUM_CHANNELS];
+	bool trigger_enabled;
+	__be16 *buffer;
+	/* Remember enabled channels and sample rate during suspend. */
+	unsigned int suspend_ctrl0;
+	struct completion completion;
+	unsigned int chan_read, chan_event;
+	int channel_users[SX9310_NUM_CHANNELS];
+	int whoami;
+};
+
+static const struct iio_event_spec sx9310_events[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
+#define SX9310_CHANNEL(idx)						 \
+	{								 \
+		.type = IIO_PROXIMITY,					 \
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		 \
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+		.indexed = 1,						 \
+		.channel = idx,						 \
+		.address = SX9310_REG_USE_MSB,				 \
+		.event_spec = sx9310_events,				 \
+		.num_event_specs = ARRAY_SIZE(sx9310_events),		 \
+		.scan_index = idx,					 \
+		.scan_type = {						 \
+			.sign = 's',					 \
+			.realbits = 16,					 \
+			.storagebits = 16,				 \
+			.endianness = IIO_BE,				 \
+		},							 \
+	}
+
+#define SX9310_DIFF_CHANNEL(idx)					 \
+	{								 \
+		.type = IIO_PROXIMITY,					 \
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		 \
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+		.indexed = 1,						 \
+		.channel = idx & SX9310_HW_CHAN_MASK,			 \
+		.channel2 = idx & SX9310_HW_CHAN_MASK,			 \
+		.address = SX9310_REG_DIFF_MSB,				 \
+		.scan_index = idx,					 \
+		.scan_type = {						 \
+			.sign = 's',					 \
+			.realbits = 12,					 \
+			.storagebits = 16,				 \
+			.endianness = IIO_BE,				 \
+		},							 \
+		.differential = 1,					 \
+	}
+
+static const struct iio_chan_spec sx9310_channels[] = {
+	SX9310_CHANNEL(0), /* USE_CS0 */
+	SX9310_CHANNEL(1), /* USE_CS1 */
+	SX9310_CHANNEL(2), /* USE_CS2 */
+	SX9310_CHANNEL(3), /* USE_COMB */
+
+	SX9310_DIFF_CHANNEL(4), /* DIFF_CS0 */
+	SX9310_DIFF_CHANNEL(5), /* DIFF_CS1 */
+	SX9310_DIFF_CHANNEL(6), /* DIFF_CS2 */
+	SX9310_DIFF_CHANNEL(7), /* DIFF_COMB */
+
+	IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+/*
+ * Each entry contains the integer part (val) and the fractional part, in micro
+ * seconds. It conforms to the IIO output IIO_VAL_INT_PLUS_MICRO.
+ */
+static const struct {
+	int val;
+	int val2;
+} sx9310_samp_freq_table[] = {
+	{ 500, 0 }, /* 0000: Min (no idle time) */
+	{ 66, 666666 }, /* 0001: 15 ms */
+	{ 33, 333333 }, /* 0010: 30 ms (Typ.) */
+	{ 22, 222222 }, /* 0011: 45 ms */
+	{ 16, 666666 }, /* 0100: 60 ms */
+	{ 11, 111111 }, /* 0101: 90 ms */
+	{ 8, 333333 }, /* 0110: 120 ms */
+	{ 5, 0 }, /* 0111: 200 ms */
+	{ 2, 500000 }, /* 1000: 400 ms */
+	{ 1, 666666 }, /* 1001: 600 ms */
+	{ 1, 250000 }, /* 1010: 800 ms */
+	{ 1, 0 }, /* 1011: 1 s */
+	{ 0, 500000 }, /* 1100: 2 s */
+	{ 0, 333333 }, /* 1101: 3 s */
+	{ 0, 250000 }, /* 1110: 4 s */
+	{ 0, 200000 }, /* 1111: 5 s */
+};
+static const unsigned int sx9310_scan_period_table[] = {
+	2,   15,  30,  45,   60,   90,	 120,  200,
+	400, 600, 800, 1000, 2000, 3000, 4000, 5000,
+};
+
+static ssize_t sx9310_show_samp_freq_avail(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	size_t len = 0;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%d ",
+				 sx9310_samp_freq_table[i].val,
+				 sx9310_samp_freq_table[i].val2);
+	buf[len - 1] = '\n';
+	return len;
+}
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sx9310_show_samp_freq_avail);
+
+static const struct regmap_range sx9310_writable_reg_ranges[] = {
+	regmap_reg_range(SX9310_REG_IRQ_MSK, SX9310_REG_IRQ_FUNC),
+	regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
+	regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
+	regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SENSOR_SEL),
+	regmap_reg_range(SX9310_REG_OFFSET_MSB, SX9310_REG_OFFSET_LSB),
+	regmap_reg_range(SX9310_REG_PAUSE, SX9310_REG_PAUSE),
+	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
+};
+
+static const struct regmap_access_table sx9310_writeable_regs = {
+	.yes_ranges = sx9310_writable_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(sx9310_writable_reg_ranges),
+};
+
+static const struct regmap_range sx9310_readable_reg_ranges[] = {
+	regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_IRQ_FUNC),
+	regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
+	regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
+	regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SAR_LSB),
+	regmap_reg_range(SX9310_REG_I2CADDR, SX9310_REG_WHOAMI),
+	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
+};
+
+static const struct regmap_access_table sx9310_readable_regs = {
+	.yes_ranges = sx9310_readable_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(sx9310_readable_reg_ranges),
+};
+
+static const struct regmap_range sx9310_volatile_reg_ranges[] = {
+	regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_STAT1),
+	regmap_reg_range(SX9310_REG_USE_MSB, SX9310_REG_DIFF_LSB),
+	regmap_reg_range(SX9310_REG_SAR_MSB, SX9310_REG_SAR_LSB),
+	regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
+};
+
+static const struct regmap_access_table sx9310_volatile_regs = {
+	.yes_ranges = sx9310_volatile_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(sx9310_volatile_reg_ranges),
+};
+
+static const struct regmap_config sx9310_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = SX9310_REG_RESET,
+	.cache_type = REGCACHE_RBTREE,
+
+	.wr_table = &sx9310_writeable_regs,
+	.rd_table = &sx9310_readable_regs,
+	.volatile_table = &sx9310_volatile_regs,
+};
+
+static int sx9310_update_chan_en(struct sx9310_data *data,
+				 unsigned int chan_read,
+				 unsigned int chan_event)
+{
+	int ret = 0;
+
+	if ((data->chan_read | data->chan_event) != (chan_read | chan_event)) {
+		ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
+					 SX9310_CHAN_ENABLED_MASK,
+					 chan_read | chan_event);
+		if (ret)
+			return ret;
+	}
+	data->chan_read = chan_read;
+	data->chan_event = chan_event;
+	return 0;
+}
+
+static int sx9310_get_read_channel(struct sx9310_data *data, int channel)
+{
+	return sx9310_update_chan_en(data, data->chan_read | BIT(channel),
+				     data->chan_event);
+}
+
+static int sx9310_put_read_channel(struct sx9310_data *data, int channel)
+{
+	return sx9310_update_chan_en(data, data->chan_read & ~BIT(channel),
+				     data->chan_event);
+}
+
+static int sx9310_get_event_channel(struct sx9310_data *data, int channel)
+{
+	return sx9310_update_chan_en(data, data->chan_read,
+				     data->chan_event | BIT(channel));
+}
+
+static int sx9310_put_event_channel(struct sx9310_data *data, int channel)
+{
+	return sx9310_update_chan_en(data, data->chan_read,
+				     data->chan_event & ~BIT(channel));
+}
+
+static int sx9310_enable_irq(struct sx9310_data *data, unsigned int irq)
+{
+	return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, irq);
+}
+
+static int sx9310_disable_irq(struct sx9310_data *data, unsigned int irq)
+{
+	return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, 0);
+}
+
+static int sx9310_read_prox_data(struct sx9310_data *data,
+				 const struct iio_chan_spec *chan, __be16 *val)
+{
+	int ret;
+
+	ret = regmap_write(data->regmap, SX9310_REG_SENSOR_SEL, chan->channel);
+	if (ret < 0)
+		return ret;
+
+	return regmap_bulk_read(data->regmap, chan->address, val, 2);
+}
+
+/*
+ * If we have no interrupt support, we have to wait for a scan period
+ * after enabling a channel to get a result.
+ */
+static int sx9310_wait_for_sample(struct sx9310_data *data)
+{
+	int ret;
+	unsigned int val;
+
+	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &val);
+	if (ret < 0)
+		return ret;
+
+	val = (val & SX9310_SCAN_PERIOD_MASK) >> SX9310_SCAN_PERIOD_SHIFT;
+
+	msleep(sx9310_scan_period_table[val]);
+
+	return 0;
+}
+
+static int sx9310_read_proximity(struct sx9310_data *data,
+				 const struct iio_chan_spec *chan, int *val)
+{
+	int ret = 0;
+	__be16 rawval;
+
+	mutex_lock(&data->mutex);
+
+	ret = sx9310_get_read_channel(data, chan->channel);
+	if (ret < 0)
+		goto out;
+
+	if (!data->trigger_enabled) {
+		ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
+		if (ret < 0)
+			goto out_put_channel;
+	}
+
+	mutex_unlock(&data->mutex);
+
+	if (data->client->irq > 0) {
+		ret = wait_for_completion_interruptible(&data->completion);
+		reinit_completion(&data->completion);
+	} else {
+		ret = sx9310_wait_for_sample(data);
+	}
+
+	mutex_lock(&data->mutex);
+
+	if (ret < 0)
+		goto out_disable_irq;
+
+	ret = sx9310_read_prox_data(data, chan, &rawval);
+	if (ret < 0)
+		goto out_disable_irq;
+
+	*val = sign_extend32(be16_to_cpu(rawval),
+			     (chan->address == SX9310_REG_DIFF_MSB ? 11 : 15));
+
+	if (!data->trigger_enabled) {
+		ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
+		if (ret < 0)
+			goto out_put_channel;
+	}
+
+	ret = sx9310_put_read_channel(data, chan->channel);
+	if (ret < 0)
+		goto out;
+
+	mutex_unlock(&data->mutex);
+
+	return IIO_VAL_INT;
+
+out_disable_irq:
+	if (!data->trigger_enabled)
+		sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
+out_put_channel:
+	sx9310_put_read_channel(data, chan->channel);
+out:
+	mutex_unlock(&data->mutex);
+
+	return ret;
+}
+
+static int sx9310_read_samp_freq(struct sx9310_data *data, int *val, int *val2)
+{
+	unsigned int regval;
+	int ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &regval);
+
+	if (ret < 0)
+		return ret;
+
+	regval = (regval & SX9310_SCAN_PERIOD_MASK) >> SX9310_SCAN_PERIOD_SHIFT;
+	*val = sx9310_samp_freq_table[regval].val;
+	*val2 = sx9310_samp_freq_table[regval].val2;
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int sx9310_read_raw(struct iio_dev *indio_dev,
+			   const struct iio_chan_spec *chan, int *val,
+			   int *val2, long mask)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+
+		ret = sx9310_read_proximity(data, chan, val);
+		iio_device_release_direct_mode(indio_dev);
+		return ret;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		return sx9310_read_samp_freq(data, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int sx9310_set_samp_freq(struct sx9310_data *data, int val, int val2)
+{
+	int i, ret;
+
+	for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
+		if (val == sx9310_samp_freq_table[i].val &&
+		    val2 == sx9310_samp_freq_table[i].val2)
+			break;
+
+	if (i == ARRAY_SIZE(sx9310_samp_freq_table))
+		return -EINVAL;
+
+	mutex_lock(&data->mutex);
+
+	ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
+				 SX9310_SCAN_PERIOD_MASK,
+				 i << SX9310_SCAN_PERIOD_SHIFT);
+
+	mutex_unlock(&data->mutex);
+
+	return ret;
+}
+
+static int sx9310_write_raw(struct iio_dev *indio_dev,
+			    const struct iio_chan_spec *chan, int val, int val2,
+			    long mask)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+		return -EINVAL;
+
+	return sx9310_set_samp_freq(data, val, val2);
+}
+
+static irqreturn_t sx9310_irq_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct sx9310_data *data = iio_priv(indio_dev);
+
+	if (data->trigger_enabled)
+		iio_trigger_poll(data->trig);
+
+	/*
+	 * Even if no event is enabled, we need to wake the thread to
+	 * clear the interrupt state by reading SX9310_REG_IRQ_SRC.  It
+	 * is not possible to do that here because regmap_read takes a
+	 * mutex.
+	 */
+	return IRQ_WAKE_THREAD;
+}
+
+static void sx9310_push_events(struct iio_dev *indio_dev)
+{
+	int ret;
+	unsigned int val, chan;
+	struct sx9310_data *data = iio_priv(indio_dev);
+	s64 timestamp = iio_get_time_ns(indio_dev);
+
+	/* Read proximity state on all channels */
+	ret = regmap_read(data->regmap, SX9310_REG_STAT0, &val);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "i2c transfer error in irq\n");
+		return;
+	}
+
+	for (chan = 0; chan < SX9310_NUM_CHANNELS; chan++) {
+		int dir;
+		u64 ev;
+		bool new_prox = val & BIT(chan);
+
+		if (!(data->chan_event & BIT(chan)))
+			continue;
+		if (new_prox == data->prox_stat[chan])
+			/* No change on this channel. */
+			continue;
+
+		dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
+		ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
+					  IIO_EV_TYPE_THRESH, dir);
+
+		iio_push_event(indio_dev, ev, timestamp);
+		data->prox_stat[chan] = new_prox;
+	}
+}
+
+static irqreturn_t sx9310_irq_thread_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret;
+	unsigned int val;
+
+	mutex_lock(&data->mutex);
+
+	ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "i2c transfer error in irq\n");
+		goto out;
+	}
+
+	if (val & (SX9310_EVENT_IRQ))
+		sx9310_push_events(indio_dev);
+
+	if (val & SX9310_CONVDONE_IRQ)
+		complete(&data->completion);
+
+out:
+	mutex_unlock(&data->mutex);
+
+	return IRQ_HANDLED;
+}
+
+static int sx9310_read_event_config(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum iio_event_type type,
+				    enum iio_event_direction dir)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+
+	return !!(data->chan_event & BIT(chan->channel));
+}
+
+static int sx9310_write_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir, int state)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret = 0;
+
+	/* If the state hasn't changed, there's nothing to do. */
+	if (!!(data->chan_event & BIT(chan->channel)) == state)
+		return 0;
+
+	mutex_lock(&data->mutex);
+	if (state) {
+		ret = sx9310_get_event_channel(data, chan->channel);
+		if (ret < 0)
+			goto out_unlock;
+		if (!(data->chan_event & ~BIT(chan->channel))) {
+			ret = sx9310_enable_irq(data, SX9310_EVENT_IRQ);
+			if (ret < 0)
+				sx9310_put_event_channel(data, chan->channel);
+		}
+	} else {
+		ret = sx9310_put_event_channel(data, chan->channel);
+		if (ret < 0)
+			goto out_unlock;
+		if (!data->chan_event) {
+			ret = sx9310_disable_irq(data, SX9310_EVENT_IRQ);
+			if (ret < 0)
+				sx9310_get_event_channel(data, chan->channel);
+		}
+	}
+
+out_unlock:
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
+static int sx9310_update_scan_mode(struct iio_dev *indio_dev,
+				   const unsigned long *scan_mask)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->mutex);
+	kfree(data->buffer);
+	data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
+	mutex_unlock(&data->mutex);
+
+	if (data->buffer == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static struct attribute *sx9310_attributes[] = {
+	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group sx9310_attribute_group = {
+	.attrs = sx9310_attributes,
+};
+
+static const struct iio_info sx9310_info = {
+	.attrs = &sx9310_attribute_group,
+	.read_raw = sx9310_read_raw,
+	.write_raw = sx9310_write_raw,
+	.read_event_config = sx9310_read_event_config,
+	.write_event_config = sx9310_write_event_config,
+	.update_scan_mode = sx9310_update_scan_mode,
+};
+
+static int sx9310_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret = 0;
+
+	mutex_lock(&data->mutex);
+
+	if (state)
+		ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
+	else if (!data->chan_read)
+		ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
+	if (ret < 0)
+		goto out;
+
+	data->trigger_enabled = state;
+
+out:
+	mutex_unlock(&data->mutex);
+
+	return ret;
+}
+
+static const struct iio_trigger_ops sx9310_trigger_ops = {
+	.set_trigger_state = sx9310_set_trigger_state,
+};
+
+static irqreturn_t sx9310_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct sx9310_data *data = iio_priv(indio_dev);
+	__be16 val;
+	int bit, ret, i = 0;
+
+	mutex_lock(&data->mutex);
+
+	for_each_set_bit(bit, indio_dev->active_scan_mask,
+			 indio_dev->masklength) {
+		ret = sx9310_read_prox_data(data, &indio_dev->channels[bit],
+					    &val);
+		if (ret < 0)
+			goto out;
+
+		data->buffer[i++] = val;
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+					   pf->timestamp);
+
+out:
+	mutex_unlock(&data->mutex);
+
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int sx9310_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	unsigned int channels = 0;
+	int bit, ret;
+
+	mutex_lock(&data->mutex);
+	for_each_set_bit(bit, indio_dev->active_scan_mask,
+			 indio_dev->masklength)
+		channels |= BIT(indio_dev->channels[bit].channel);
+
+	ret = sx9310_update_chan_en(data, channels, data->chan_event);
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
+static int sx9310_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->mutex);
+	ret = sx9310_update_chan_en(data, 0, data->chan_event);
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
+static const struct iio_buffer_setup_ops sx9310_buffer_setup_ops = {
+	.preenable = sx9310_buffer_preenable,
+	.postenable = iio_triggered_buffer_postenable,
+	.predisable = iio_triggered_buffer_predisable,
+	.postdisable = sx9310_buffer_postdisable,
+};
+
+struct sx9310_reg_default {
+	u8 reg;
+	u8 def;
+};
+
+#define SX_INIT(_reg, _def)			\
+	{					\
+		.reg = SX9310_REG_##_reg,	\
+		.def = _def,			\
+	}
+
+static const struct sx9310_reg_default sx9310_default_regs[] = {
+	SX_INIT(IRQ_MSK, 0x00),
+	SX_INIT(IRQ_FUNC, 0x00),
+	/*
+	 * The lower 4 bits should not be set as it enable sensors measurements.
+	 * Turning the detection on before the configuration values are set to
+	 * good values can cause the device to return erroneous readings.
+	 */
+	SX_INIT(PROX_CTRL0, SX9310_REG_PROX_CTRL0_PROXSTAT2),
+	SX_INIT(PROX_CTRL1, 0x00),
+	SX_INIT(PROX_CTRL2, SX9310_REG_PROX_CTRL2_COMBMODE_ALL |
+			    SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC),
+	SX_INIT(PROX_CTRL3, SX9310_REG_PROX_CTRL3_GAIN0_X8 |
+			    SX9310_REG_PROX_CTRL3_GAIN12_X4),
+	SX_INIT(PROX_CTRL4, SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST),
+	SX_INIT(PROX_CTRL5, SX9310_REG_PROX_CTRL5_RANGE_SMALL |
+			    SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1 |
+			    SX9310_REG_PROX_CTRL5_RAWFILT_1P25),
+	SX_INIT(PROX_CTRL6, SX9310_REG_PROX_CTRL6_COMP_COMMON),
+	SX_INIT(PROX_CTRL7, SX9310_REG_PROX_CTRL7_AVGNEGFILT_2 |
+			    SX9310_REG_PROX_CTRL7_AVGPOSFILT_512),
+	SX_INIT(PROX_CTRL8, SX9310_REG_PROX_CTRL8_9_PTHRESH_96 |
+			    SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500),
+	SX_INIT(PROX_CTRL9, SX9310_REG_PROX_CTRL8_9_PTHRESH12_28 |
+			    SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900),
+	SX_INIT(PROX_CTRL10, SX9310_REG_PROX_CTRL10_HYST_6PCT |
+			     SX9310_REG_PROX_CTRL10_CLOSE_DEBOUNCE_8 |
+			     SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_8),
+	SX_INIT(PROX_CTRL11, 0x00),
+	SX_INIT(PROX_CTRL12, 0x00),
+	SX_INIT(PROX_CTRL13, 0x00),
+	SX_INIT(PROX_CTRL14, 0x00),
+	SX_INIT(PROX_CTRL15, 0x00),
+	SX_INIT(PROX_CTRL16, 0x00),
+	SX_INIT(PROX_CTRL17, 0x00),
+	SX_INIT(PROX_CTRL18, 0x00),
+	SX_INIT(PROX_CTRL19, 0x00),
+	SX_INIT(SAR_CTRL0, SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES |
+			   SX9310_REG_SAR_CTRL0_SARHYST_8),
+	SX_INIT(SAR_CTRL1, SX9310_REG_SAR_CTRL1_SLOPE(10781250)),
+	SX_INIT(SAR_CTRL2, SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT),
+};
+
+/* Activate all channels and perform an initial compensation. */
+static int sx9310_init_compensation(struct iio_dev *indio_dev)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int i, ret;
+	unsigned int val;
+	unsigned int ctrl0;
+
+	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &ctrl0);
+	if (ret < 0)
+		return ret;
+
+	/* run the compensation phase on all channels */
+	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
+			   ctrl0 | SX9310_REG_PROX_CTRL0_EN_MASK);
+	if (ret < 0)
+		return ret;
+
+	for (i = 100; i >= 0; i--) {
+		msleep(20);
+		ret = regmap_read(data->regmap, SX9310_REG_STAT1, &val);
+		if (ret < 0)
+			goto out;
+		if (!(val & SX9310_COMPSTAT_MASK))
+			break;
+	}
+
+	if (i < 0) {
+		dev_err(&data->client->dev,
+			"initial compensation timed out: 0x%02x", val);
+		ret = -ETIMEDOUT;
+	}
+
+out:
+	regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
+	return ret;
+}
+
+static int sx9310_init_device(struct iio_dev *indio_dev)
+{
+	struct sx9310_data *data = iio_priv(indio_dev);
+	const struct sx9310_reg_default *initval;
+	int ret;
+	unsigned int i, val;
+
+	/* Soft reset the device. */
+	ret = regmap_write(data->regmap, SX9310_REG_RESET, SX9310_SOFT_RESET);
+	if (ret < 0)
+		return ret;
+
+	usleep_range(1000, 2000); /* power-up time is ~1ms. */
+
+	/* Clear reset interrupt state by reading SX9310_REG_IRQ_SRC. */
+	ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
+	if (ret < 0)
+		return ret;
+
+	/* Program some sane defaults. */
+	for (i = 0; i < ARRAY_SIZE(sx9310_default_regs); i++) {
+		initval = &sx9310_default_regs[i];
+		ret = regmap_write(data->regmap, initval->reg, initval->def);
+		if (ret < 0)
+			return ret;
+	}
+
+	return sx9310_init_compensation(indio_dev);
+}
+
+static int sx9310_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct sx9310_data *data;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	mutex_init(&data->mutex);
+	init_completion(&data->completion);
+
+	data->regmap = devm_regmap_init_i2c(client, &sx9310_regmap_config);
+	if (IS_ERR(data->regmap))
+		return PTR_ERR(data->regmap);
+
+	ret = regmap_read(data->regmap, SX9310_REG_WHOAMI, &data->whoami);
+	if (ret < 0) {
+		dev_err(&client->dev, "error in reading WHOAMI register: %d",
+			ret);
+		return ret;
+	}
+	switch (data->whoami) {
+	case SX9310_WHOAMI_VALUE:
+		indio_dev->name = "sx9310";
+		break;
+	case SX9311_WHOAMI_VALUE:
+		indio_dev->name = "sx9311";
+		break;
+	default:
+		dev_err(&client->dev, "unexpected WHOAMI response: %u",
+			data->whoami);
+		return -ENODEV;
+	}
+
+	ACPI_COMPANION_SET(&indio_dev->dev, ACPI_COMPANION(&client->dev));
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->channels = sx9310_channels;
+	indio_dev->num_channels = ARRAY_SIZE(sx9310_channels);
+	indio_dev->info = &sx9310_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	i2c_set_clientdata(client, indio_dev);
+
+	ret = sx9310_init_device(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	if (client->irq >= 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						sx9310_irq_handler,
+						sx9310_irq_thread_handler,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						"sx9310_event", indio_dev);
+		if (ret < 0)
+			return ret;
+
+		data->trig =
+			devm_iio_trigger_alloc(&client->dev, "%s-dev%d",
+					       indio_dev->name, indio_dev->id);
+		if (!data->trig)
+			return -ENOMEM;
+
+		data->trig->dev.parent = &client->dev;
+		data->trig->ops = &sx9310_trigger_ops;
+		iio_trigger_set_drvdata(data->trig, indio_dev);
+
+		ret = devm_iio_trigger_register(&client->dev, data->trig);
+		if (ret)
+			return ret;
+	}
+
+	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
+					      iio_pollfunc_store_time,
+					      sx9310_trigger_handler,
+					      &sx9310_buffer_setup_ops);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_iio_device_register(&client->dev, indio_dev);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int sx9310_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct sx9310_data *data = iio_priv(indio_dev);
+
+	kfree(data->buffer);
+	return 0;
+}
+
+static int __maybe_unused sx9310_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct sx9310_data *data = iio_priv(indio_dev);
+	u8 ctrl0;
+	int ret;
+
+	disable_irq_nosync(data->client->irq);
+
+	mutex_lock(&data->mutex);
+	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0,
+			  &data->suspend_ctrl0);
+
+	if (ret)
+		goto out;
+
+	ctrl0 = data->suspend_ctrl0 & ~SX9310_REG_PROX_CTRL0_EN_MASK;
+	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
+	if (ret)
+		goto out;
+
+	ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 0);
+
+out:
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
+static int __maybe_unused sx9310_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct sx9310_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->mutex);
+	ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 1);
+	if (ret)
+		goto out;
+
+	ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
+			   data->suspend_ctrl0);
+
+out:
+	mutex_unlock(&data->mutex);
+
+	enable_irq(data->client->irq);
+
+	return ret;
+}
+
+static const struct dev_pm_ops sx9310_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(sx9310_suspend, sx9310_resume)
+};
+
+static const struct acpi_device_id sx9310_acpi_match[] = {
+	{ "STH9310", 0 },
+	{ "STH9311", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, sx9310_acpi_match);
+
+static const struct of_device_id sx9310_of_match[] = {
+	{ .compatible = "semtech,sx9310" },
+	{ .compatible = "semtech,sx9311" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sx9310_of_match);
+
+static const struct i2c_device_id sx9310_id[] = {
+	{ "sx9310", 0 },
+	{ "sx9311", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, sx9310_id);
+
+static struct i2c_driver sx9310_driver = {
+	.driver = {
+		.name	= "sx9310",
+		.acpi_match_table = ACPI_PTR(sx9310_acpi_match),
+		.of_match_table = of_match_ptr(sx9310_of_match),
+		.pm = &sx9310_pm_ops,
+	},
+	.probe		= sx9310_probe,
+	.remove		= sx9310_remove,
+	.id_table	= sx9310_id,
+};
+module_i2c_driver(sx9310_driver);
+
+MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
+MODULE_AUTHOR("Daniel Campello <campello@chromium.org>");
+MODULE_DESCRIPTION("Driver for Semtech SX9310/SX9311 proximity sensor");
+MODULE_LICENSE("GPL v2");