Commit 227c83fa authored by Stephen Boyd's avatar Stephen Boyd Committed by Jonathan Cameron
Browse files

iio: sx9310: Support hardware gain factor 



Add support to set the hardware gain of the channels as a multiplier of
2x, 4x, or 8x.

Signed-off-by: default avatarStephen Boyd <swboyd@chromium.org>
Cc: Daniel Campello <campello@chromium.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Gwendal Grignou <gwendal@chromium.org>
Cc: Evan Green <evgreen@chromium.org>
Link: https://lore.kernel.org/r/20201007011735.1346994-2-swboyd@chromium.org


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 324b9f29

drivers/iio/proximity/sx9310.c

+104 −5
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/i2c.h>

#include <linux/irq.h>

#include <linux/kernel.h>

#include <linux/log2.h>

#include <linux/mod_devicetable.h>

#include <linux/module.h>

#include <linux/pm.h>
@@ -51,7 +52,9 @@ 
#define   SX9310_REG_PROX_CTRL2_COMBMODE_CS1_CS2	(0x02 << 6)

#define   SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC	(0x01 << 2)

#define SX9310_REG_PROX_CTRL3				0x13

#define   SX9310_REG_PROX_CTRL3_GAIN0_MASK		GENMASK(3, 2)

#define   SX9310_REG_PROX_CTRL3_GAIN0_X8		(0x03 << 2)

#define   SX9310_REG_PROX_CTRL3_GAIN12_MASK		GENMASK(1, 0)

#define   SX9310_REG_PROX_CTRL3_GAIN12_X4		0x02

#define SX9310_REG_PROX_CTRL4				0x14

#define   SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST	0x07
@@ -145,15 +148,18 @@ 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),

		.mask_separate = BIT(IIO_EV_INFO_ENABLE) | BIT(IIO_EV_INFO_VALUE),

	},

};



#define SX9310_NAMED_CHANNEL(idx, name)					 \

	{								 \

		.type = IIO_PROXIMITY,					 \

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		 \

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		 \

				      BIT(IIO_CHAN_INFO_HARDWAREGAIN),   \

		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \

		.info_mask_separate_available =				 \

			BIT(IIO_CHAN_INFO_HARDWAREGAIN),		 \

		.indexed = 1,						 \

		.channel = idx,						 \

		.extend_name = name,					 \
@@ -426,6 +432,34 @@ static int sx9310_read_proximity(struct sx9310_data *data, 
	return ret;

}



static int sx9310_read_gain(struct sx9310_data *data,

			    const struct iio_chan_spec *chan, int *val)

{

	unsigned int regval, gain;

	int ret;



	ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL3, &regval);

	if (ret)

		return ret;



	switch (chan->channel) {

	case 0:

	case 3:

		gain = FIELD_GET(SX9310_REG_PROX_CTRL3_GAIN0_MASK, regval);

		break;

	case 1:

	case 2:

		gain = FIELD_GET(SX9310_REG_PROX_CTRL3_GAIN12_MASK, regval);

		break;

	default:

		return -EINVAL;

	}



	*val = 1 << gain;



	return IIO_VAL_INT;

}



static int sx9310_read_samp_freq(struct sx9310_data *data, int *val, int *val2)

{

	unsigned int regval;
@@ -461,6 +495,14 @@ static int sx9310_read_raw(struct iio_dev *indio_dev, 
		ret = sx9310_read_proximity(data, chan, val);

		iio_device_release_direct_mode(indio_dev);

		return ret;

	case IIO_CHAN_INFO_HARDWAREGAIN:

		ret = iio_device_claim_direct_mode(indio_dev);

		if (ret)

			return ret;



		ret = sx9310_read_gain(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:
@@ -468,6 +510,27 @@ static int sx9310_read_raw(struct iio_dev *indio_dev, 
	}

}



static const int sx9310_gain_vals[] = { 1, 2, 4, 8 };



static int sx9310_read_avail(struct iio_dev *indio_dev,

			     struct iio_chan_spec const *chan,

			     const int **vals, int *type, int *length,

			     long mask)

{

	if (chan->type != IIO_PROXIMITY)

		return -EINVAL;



	switch (mask) {

	case IIO_CHAN_INFO_HARDWAREGAIN:

		*type = IIO_VAL_INT;

		*length = ARRAY_SIZE(sx9310_gain_vals);

		*vals = sx9310_gain_vals;

		return IIO_AVAIL_LIST;

	}



	return -EINVAL;

}



static int sx9310_set_samp_freq(struct sx9310_data *data, int val, int val2)

{

	int i, ret;
@@ -492,6 +555,37 @@ static int sx9310_set_samp_freq(struct sx9310_data *data, int val, int val2) 
	return ret;

}



static int sx9310_write_gain(struct sx9310_data *data,

			    const struct iio_chan_spec *chan, int val)

{

	unsigned int gain, mask;

	int ret;



	gain = ilog2(val);



	switch (chan->channel) {

	case 0:

	case 3:

		mask = SX9310_REG_PROX_CTRL3_GAIN0_MASK;

		gain = FIELD_PREP(SX9310_REG_PROX_CTRL3_GAIN0_MASK, gain);

		break;

	case 1:

	case 2:

		mask = SX9310_REG_PROX_CTRL3_GAIN12_MASK;

		gain = FIELD_PREP(SX9310_REG_PROX_CTRL3_GAIN12_MASK, gain);

		break;

	default:

		return -EINVAL;

	}



	mutex_lock(&data->mutex);

	ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL3, mask,

				 gain);

	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)
@@ -501,10 +595,14 @@ static int sx9310_write_raw(struct iio_dev *indio_dev, 
	if (chan->type != IIO_PROXIMITY)

		return -EINVAL;



	if (mask != IIO_CHAN_INFO_SAMP_FREQ)

		return -EINVAL;



	switch (mask) {

	case IIO_CHAN_INFO_SAMP_FREQ:

		return sx9310_set_samp_freq(data, val, val2);

	case IIO_CHAN_INFO_HARDWAREGAIN:

		return sx9310_write_gain(data, chan, val);

	}



	return -EINVAL;

}



static irqreturn_t sx9310_irq_handler(int irq, void *private)
@@ -645,6 +743,7 @@ static const struct attribute_group sx9310_attribute_group = { 
static const struct iio_info sx9310_info = {

	.attrs = &sx9310_attribute_group,

	.read_raw = sx9310_read_raw,

	.read_avail = sx9310_read_avail,

	.write_raw = sx9310_write_raw,

	.read_event_config = sx9310_read_event_config,

	.write_event_config = sx9310_write_event_config,