drivers/iio/light/adux1020.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * adux1020.c - Support for Analog Devices ADUX1020 photometric sensor
  *
  * Copyright (C) 2019 Linaro Ltd.
  * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
  *
  * TODO: Triggered buffer support
  */

 #include <linux/bitfield.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/regmap.h>

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

 #define ADUX1020_REGMAP_NAME		"adux1020_regmap"
 #define ADUX1020_DRV_NAME		"adux1020"

 /* System registers */
 #define ADUX1020_REG_CHIP_ID		0x08
 #define ADUX1020_REG_SLAVE_ADDRESS	0x09

 #define ADUX1020_REG_SW_RESET		0x0f
 #define ADUX1020_REG_INT_ENABLE		0x1c
 #define ADUX1020_REG_INT_POLARITY	0x1d
 #define ADUX1020_REG_PROX_TH_ON1	0x2a
 #define ADUX1020_REG_PROX_TH_OFF1	0x2b
 #define	ADUX1020_REG_PROX_TYPE		0x2f
 #define	ADUX1020_REG_TEST_MODES_3	0x32
 #define	ADUX1020_REG_FORCE_MODE		0x33
 #define	ADUX1020_REG_FREQUENCY		0x40
 #define ADUX1020_REG_LED_CURRENT	0x41
 #define	ADUX1020_REG_OP_MODE		0x45
 #define	ADUX1020_REG_INT_MASK		0x48
 #define	ADUX1020_REG_INT_STATUS		0x49
 #define	ADUX1020_REG_DATA_BUFFER	0x60

 /* Chip ID bits */
 #define ADUX1020_CHIP_ID_MASK		GENMASK(11, 0)
 #define ADUX1020_CHIP_ID		0x03fc

 #define ADUX1020_SW_RESET		BIT(1)
 #define ADUX1020_FIFO_FLUSH		BIT(15)
 #define ADUX1020_OP_MODE_MASK		GENMASK(3, 0)
 #define ADUX1020_DATA_OUT_MODE_MASK	GENMASK(7, 4)
 #define ADUX1020_DATA_OUT_PROX_I	FIELD_PREP(ADUX1020_DATA_OUT_MODE_MASK, 1)

 #define ADUX1020_MODE_INT_MASK		GENMASK(7, 0)
 #define ADUX1020_INT_ENABLE		0x2094
 #define ADUX1020_INT_DISABLE		0x2090
 #define ADUX1020_PROX_INT_ENABLE	0x00f0
 #define ADUX1020_PROX_ON1_INT		BIT(0)
 #define ADUX1020_PROX_OFF1_INT		BIT(1)
 #define ADUX1020_FIFO_INT_ENABLE	0x7f
 #define ADUX1020_MODE_INT_DISABLE	0xff
 #define ADUX1020_MODE_INT_STATUS_MASK	GENMASK(7, 0)
 #define ADUX1020_FIFO_STATUS_MASK	GENMASK(15, 8)
 #define ADUX1020_INT_CLEAR		0xff
 #define ADUX1020_PROX_TYPE		BIT(15)

 #define ADUX1020_INT_PROX_ON1		BIT(0)
 #define ADUX1020_INT_PROX_OFF1		BIT(1)

 #define ADUX1020_FORCE_CLOCK_ON		0x0f4f
 #define ADUX1020_FORCE_CLOCK_RESET	0x0040
 #define ADUX1020_ACTIVE_4_STATE		0x0008

 #define ADUX1020_PROX_FREQ_MASK		GENMASK(7, 4)
 #define ADUX1020_PROX_FREQ(x)		FIELD_PREP(ADUX1020_PROX_FREQ_MASK, x)

 #define ADUX1020_LED_CURRENT_MASK	GENMASK(3, 0)
 #define ADUX1020_LED_PIREF_EN		BIT(12)

 /* Operating modes */
 enum adux1020_op_modes {
 	ADUX1020_MODE_STANDBY,
 	ADUX1020_MODE_PROX_I,
 	ADUX1020_MODE_PROX_XY,
 	ADUX1020_MODE_GEST,
 	ADUX1020_MODE_SAMPLE,
 	ADUX1020_MODE_FORCE = 0x0e,
 	ADUX1020_MODE_IDLE = 0x0f,
 };

 struct adux1020_data {
 	struct i2c_client *client;
 	struct iio_dev *indio_dev;
 	struct mutex lock;
 	struct regmap *regmap;
 };

 struct adux1020_mode_data {
 	u8 bytes;
 	u8 buf_len;
 	u16 int_en;
 };

 static const struct adux1020_mode_data adux1020_modes[] = {
 	[ADUX1020_MODE_PROX_I] = {
 		.bytes = 2,
 		.buf_len = 1,
 		.int_en = ADUX1020_PROX_INT_ENABLE,
 	},
 };

 static const struct regmap_config adux1020_regmap_config = {
 	.name = ADUX1020_REGMAP_NAME,
 	.reg_bits = 8,
 	.val_bits = 16,
 	.max_register = 0x6F,
 	.cache_type = REGCACHE_NONE,
 };

 static const struct reg_sequence adux1020_def_conf[] = {
 	{ 0x000c, 0x000f },
 	{ 0x0010, 0x1010 },
 	{ 0x0011, 0x004c },
 	{ 0x0012, 0x5f0c },
 	{ 0x0013, 0xada5 },
 	{ 0x0014, 0x0080 },
 	{ 0x0015, 0x0000 },
 	{ 0x0016, 0x0600 },
 	{ 0x0017, 0x0000 },
 	{ 0x0018, 0x2693 },
 	{ 0x0019, 0x0004 },
 	{ 0x001a, 0x4280 },
 	{ 0x001b, 0x0060 },
 	{ 0x001c, 0x2094 },
 	{ 0x001d, 0x0020 },
 	{ 0x001e, 0x0001 },
 	{ 0x001f, 0x0100 },
 	{ 0x0020, 0x0320 },
 	{ 0x0021, 0x0A13 },
 	{ 0x0022, 0x0320 },
 	{ 0x0023, 0x0113 },
 	{ 0x0024, 0x0000 },
 	{ 0x0025, 0x2412 },
 	{ 0x0026, 0x2412 },
 	{ 0x0027, 0x0022 },
 	{ 0x0028, 0x0000 },
 	{ 0x0029, 0x0300 },
 	{ 0x002a, 0x0700 },
 	{ 0x002b, 0x0600 },
 	{ 0x002c, 0x6000 },
 	{ 0x002d, 0x4000 },
 	{ 0x002e, 0x0000 },
 	{ 0x002f, 0x0000 },
 	{ 0x0030, 0x0000 },
 	{ 0x0031, 0x0000 },
 	{ 0x0032, 0x0040 },
 	{ 0x0033, 0x0008 },
 	{ 0x0034, 0xE400 },
 	{ 0x0038, 0x8080 },
 	{ 0x0039, 0x8080 },
 	{ 0x003a, 0x2000 },
 	{ 0x003b, 0x1f00 },
 	{ 0x003c, 0x2000 },
 	{ 0x003d, 0x2000 },
 	{ 0x003e, 0x0000 },
 	{ 0x0040, 0x8069 },
 	{ 0x0041, 0x1f2f },
 	{ 0x0042, 0x4000 },
 	{ 0x0043, 0x0000 },
 	{ 0x0044, 0x0008 },
 	{ 0x0046, 0x0000 },
 	{ 0x0048, 0x00ef },
 	{ 0x0049, 0x0000 },
 	{ 0x0045, 0x0000 },
 };

 static const int adux1020_rates[][2] = {
 	{ 0, 100000 },
 	{ 0, 200000 },
 	{ 0, 500000 },
 	{ 1, 0 },
 	{ 2, 0 },
 	{ 5, 0 },
 	{ 10, 0 },
 	{ 20, 0 },
 	{ 50, 0 },
 	{ 100, 0 },
 	{ 190, 0 },
 	{ 450, 0 },
 	{ 820, 0 },
 	{ 1400, 0 },
 };

 static const int adux1020_led_currents[][2] = {
 	{ 0, 25000 },
 	{ 0, 40000 },
 	{ 0, 55000 },
 	{ 0, 70000 },
 	{ 0, 85000 },
 	{ 0, 100000 },
 	{ 0, 115000 },
 	{ 0, 130000 },
 	{ 0, 145000 },
 	{ 0, 160000 },
 	{ 0, 175000 },
 	{ 0, 190000 },
 	{ 0, 205000 },
 	{ 0, 220000 },
 	{ 0, 235000 },
 	{ 0, 250000 },
 };

 static int adux1020_flush_fifo(struct adux1020_data *data)
 {
 	int ret;

 	/* Force Idle mode */
 	ret = regmap_write(data->regmap, ADUX1020_REG_FORCE_MODE,
 			   ADUX1020_ACTIVE_4_STATE);
 	if (ret < 0)
 		return ret;

 	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
 				 ADUX1020_OP_MODE_MASK, ADUX1020_MODE_FORCE);
 	if (ret < 0)
 		return ret;

 	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
 				 ADUX1020_OP_MODE_MASK, ADUX1020_MODE_IDLE);
 	if (ret < 0)
 		return ret;

 	/* Flush FIFO */
 	ret = regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
 			   ADUX1020_FORCE_CLOCK_ON);
 	if (ret < 0)
 		return ret;

 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_STATUS,
 			   ADUX1020_FIFO_FLUSH);
 	if (ret < 0)
 		return ret;

 	return regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
 			    ADUX1020_FORCE_CLOCK_RESET);
 }

 static int adux1020_read_fifo(struct adux1020_data *data, u16 *buf, u8 buf_len)
 {
 	unsigned int regval;
 	int i, ret;

 	/* Enable 32MHz clock */
 	ret = regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
 			   ADUX1020_FORCE_CLOCK_ON);
 	if (ret < 0)
 		return ret;

 	for (i = 0; i < buf_len; i++) {
 		ret = regmap_read(data->regmap, ADUX1020_REG_DATA_BUFFER,
 				  &regval);
 		if (ret < 0)
 			return ret;

 		buf[i] = regval;
 	}

 	/* Set 32MHz clock to be controlled by internal state machine */
 	return regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
 			    ADUX1020_FORCE_CLOCK_RESET);
 }

 static int adux1020_set_mode(struct adux1020_data *data,
 			     enum adux1020_op_modes mode)
 {
 	int ret;

 	/* Switch to standby mode before changing the mode */
 	ret = regmap_write(data->regmap, ADUX1020_REG_OP_MODE,
 			   ADUX1020_MODE_STANDBY);
 	if (ret < 0)
 		return ret;

 	/* Set data out and switch to the desired mode */
 	switch (mode) {
 	case ADUX1020_MODE_PROX_I:
 		ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
 					 ADUX1020_DATA_OUT_MODE_MASK,
 					 ADUX1020_DATA_OUT_PROX_I);
 		if (ret < 0)
 			return ret;

 		ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
 					 ADUX1020_OP_MODE_MASK,
 					 ADUX1020_MODE_PROX_I);
 		if (ret < 0)
 			return ret;
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static int adux1020_measure(struct adux1020_data *data,
 			    enum adux1020_op_modes mode,
 			    u16 *val)
 {
 	unsigned int status;
 	int ret, tries = 50;

 	/* Disable INT pin as polling is going to be used */
 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_ENABLE,
 			   ADUX1020_INT_DISABLE);
 	if (ret < 0)
 		return ret;

 	/* Enable mode interrupt */
 	ret = regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
 				 ADUX1020_MODE_INT_MASK,
 				 adux1020_modes[mode].int_en);
 	if (ret < 0)
 		return ret;

 	while (tries--) {
 		ret = regmap_read(data->regmap, ADUX1020_REG_INT_STATUS,
 				  &status);
 		if (ret < 0)
 			return ret;

 		status &= ADUX1020_FIFO_STATUS_MASK;
 		if (status >= adux1020_modes[mode].bytes)
 			break;
 		msleep(20);
 	}

 	if (tries < 0)
 		return -EIO;

 	ret = adux1020_read_fifo(data, val, adux1020_modes[mode].buf_len);
 	if (ret < 0)
 		return ret;

 	/* Clear mode interrupt */
 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_STATUS,
 			   (~adux1020_modes[mode].int_en));
 	if (ret < 0)
 		return ret;

 	/* Disable mode interrupts */
 	return regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
 				  ADUX1020_MODE_INT_MASK,
 				  ADUX1020_MODE_INT_DISABLE);
 }

 static int adux1020_read_raw(struct iio_dev *indio_dev,
 			     struct iio_chan_spec const *chan,
 			     int *val, int *val2, long mask)
 {
 	struct adux1020_data *data = iio_priv(indio_dev);
 	u16 buf[3];
 	int ret = -EINVAL;
 	unsigned int regval;

 	mutex_lock(&data->lock);

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		switch (chan->type) {
 		case IIO_PROXIMITY:
 			ret = adux1020_set_mode(data, ADUX1020_MODE_PROX_I);
 			if (ret < 0)
 				goto fail;

 			ret = adux1020_measure(data, ADUX1020_MODE_PROX_I, buf);
 			if (ret < 0)
 				goto fail;

 			*val = buf[0];
 			ret = IIO_VAL_INT;
 			break;
 		default:
 			break;
 		}
 		break;
 	case IIO_CHAN_INFO_PROCESSED:
 		switch (chan->type) {
 		case IIO_CURRENT:
 			ret = regmap_read(data->regmap,
 					  ADUX1020_REG_LED_CURRENT, &regval);
 			if (ret < 0)
 				goto fail;

 			regval = regval & ADUX1020_LED_CURRENT_MASK;

 			*val = adux1020_led_currents[regval][0];
 			*val2 = adux1020_led_currents[regval][1];

 			ret = IIO_VAL_INT_PLUS_MICRO;
 			break;
 		default:
 			break;
 		}
 		break;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		switch (chan->type) {
 		case IIO_PROXIMITY:
 			ret = regmap_read(data->regmap, ADUX1020_REG_FREQUENCY,
 					  &regval);
 			if (ret < 0)
 				goto fail;

 			regval = FIELD_GET(ADUX1020_PROX_FREQ_MASK, regval);

 			*val = adux1020_rates[regval][0];
 			*val2 = adux1020_rates[regval][1];

 			ret = IIO_VAL_INT_PLUS_MICRO;
 			break;
 		default:
 			break;
 		}
 		break;
 	default:
 		break;
 	}

 fail:
 	mutex_unlock(&data->lock);

 	return ret;
 };

 static inline int adux1020_find_index(const int array[][2], int count, int val,
 				      int val2)
 {
 	int i;

 	for (i = 0; i < count; i++)
 		if (val == array[i][0] && val2 == array[i][1])
 			return i;

 	return -EINVAL;
 }

 static int adux1020_write_raw(struct iio_dev *indio_dev,
 			      struct iio_chan_spec const *chan,
 			      int val, int val2, long mask)
 {
 	struct adux1020_data *data = iio_priv(indio_dev);
 	int i, ret = -EINVAL;

 	mutex_lock(&data->lock);

 	switch (mask) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		if (chan->type == IIO_PROXIMITY) {
 			i = adux1020_find_index(adux1020_rates,
 						ARRAY_SIZE(adux1020_rates),
 						val, val2);
 			if (i < 0) {
 				ret = i;
 				goto fail;
 			}

 			ret = regmap_update_bits(data->regmap,
 						 ADUX1020_REG_FREQUENCY,
 						 ADUX1020_PROX_FREQ_MASK,
 						 ADUX1020_PROX_FREQ(i));
 		}
 		break;
 	case IIO_CHAN_INFO_PROCESSED:
 		if (chan->type == IIO_CURRENT) {
 			i = adux1020_find_index(adux1020_led_currents,
 					ARRAY_SIZE(adux1020_led_currents),
 					val, val2);
 			if (i < 0) {
 				ret = i;
 				goto fail;
 			}

 			ret = regmap_update_bits(data->regmap,
 						 ADUX1020_REG_LED_CURRENT,
 						 ADUX1020_LED_CURRENT_MASK, i);
 		}
 		break;
 	default:
 		break;
 	}

 fail:
 	mutex_unlock(&data->lock);

 	return ret;
 }

 static int adux1020_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 adux1020_data *data = iio_priv(indio_dev);
 	int ret, mask;

 	mutex_lock(&data->lock);

 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_ENABLE,
 			   ADUX1020_INT_ENABLE);
 	if (ret < 0)
 		goto fail;

 	ret = regmap_write(data->regmap, ADUX1020_REG_INT_POLARITY, 0);
 	if (ret < 0)
 		goto fail;

 	switch (chan->type) {
 	case IIO_PROXIMITY:
 		if (dir == IIO_EV_DIR_RISING)
 			mask = ADUX1020_PROX_ON1_INT;
 		else
 			mask = ADUX1020_PROX_OFF1_INT;

 		if (state)
 			state = 0;
 		else
 			state = mask;

 		ret = regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
 					 mask, state);
 		if (ret < 0)
 			goto fail;

 		/*
 		 * Trigger proximity interrupt when the intensity is above
 		 * or below threshold
 		 */
 		ret = regmap_update_bits(data->regmap, ADUX1020_REG_PROX_TYPE,
 					 ADUX1020_PROX_TYPE,
 					 ADUX1020_PROX_TYPE);
 		if (ret < 0)
 			goto fail;

 		/* Set proximity mode */
 		ret = adux1020_set_mode(data, ADUX1020_MODE_PROX_I);
 		break;
 	default:
 		ret = -EINVAL;
 		break;
 	}

 fail:
 	mutex_unlock(&data->lock);

 	return ret;
 }

 static int adux1020_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 adux1020_data *data = iio_priv(indio_dev);
 	int ret, mask;
 	unsigned int regval;

 	switch (chan->type) {
 	case IIO_PROXIMITY:
 		if (dir == IIO_EV_DIR_RISING)
 			mask = ADUX1020_PROX_ON1_INT;
 		else
 			mask = ADUX1020_PROX_OFF1_INT;
 		break;
 	default:
 		return -EINVAL;
 	}

 	ret = regmap_read(data->regmap, ADUX1020_REG_INT_MASK, &regval);
 	if (ret < 0)
 		return ret;

 	return !(regval & mask);
 }

 static int adux1020_read_thresh(struct iio_dev *indio_dev,
 				const struct iio_chan_spec *chan,
 				enum iio_event_type type,
 				enum iio_event_direction dir,
 				enum iio_event_info info, int *val, int *val2)
 {
 	struct adux1020_data *data = iio_priv(indio_dev);
 	u8 reg;
 	int ret;
 	unsigned int regval;

 	switch (chan->type) {
 	case IIO_PROXIMITY:
 		if (dir == IIO_EV_DIR_RISING)
 			reg = ADUX1020_REG_PROX_TH_ON1;
 		else
 			reg = ADUX1020_REG_PROX_TH_OFF1;
 		break;
 	default:
 		return -EINVAL;
 	}

 	ret = regmap_read(data->regmap, reg, &regval);
 	if (ret < 0)
 		return ret;

 	*val = regval;

 	return IIO_VAL_INT;
 }

 static int adux1020_write_thresh(struct iio_dev *indio_dev,
 				 const struct iio_chan_spec *chan,
 				 enum iio_event_type type,
 				 enum iio_event_direction dir,
 				 enum iio_event_info info, int val, int val2)
 {
 	struct adux1020_data *data = iio_priv(indio_dev);
 	u8 reg;

 	switch (chan->type) {
 	case IIO_PROXIMITY:
 		if (dir == IIO_EV_DIR_RISING)
 			reg = ADUX1020_REG_PROX_TH_ON1;
 		else
 			reg = ADUX1020_REG_PROX_TH_OFF1;
 		break;
 	default:
 		return -EINVAL;
 	}

 	/* Full scale threshold value is 0-65535  */
 	if (val < 0 || val > 65535)
 		return -EINVAL;

 	return regmap_write(data->regmap, reg, val);
 }

 static const struct iio_event_spec adux1020_proximity_event[] = {
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_RISING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_FALLING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 };

 static const struct iio_chan_spec adux1020_channels[] = {
 	{
 		.type = IIO_PROXIMITY,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 				      BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.event_spec = adux1020_proximity_event,
 		.num_event_specs = ARRAY_SIZE(adux1020_proximity_event),
 	},
 	{
 		.type = IIO_CURRENT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
 		.extend_name = "led",
 		.output = 1,
 	},
 };

 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 		      "0.1 0.2 0.5 1 2 5 10 20 50 100 190 450 820 1400");

 static struct attribute *adux1020_attributes[] = {
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
 	NULL
 };

 static const struct attribute_group adux1020_attribute_group = {
 	.attrs = adux1020_attributes,
 };

 static const struct iio_info adux1020_info = {
 	.attrs = &adux1020_attribute_group,
 	.read_raw = adux1020_read_raw,
 	.write_raw = adux1020_write_raw,
 	.read_event_config = adux1020_read_event_config,
 	.write_event_config = adux1020_write_event_config,
 	.read_event_value = adux1020_read_thresh,
 	.write_event_value = adux1020_write_thresh,
 };

 static irqreturn_t adux1020_interrupt_handler(int irq, void *private)
 {
 	struct iio_dev *indio_dev = private;
 	struct adux1020_data *data = iio_priv(indio_dev);
 	int ret, status;

 	ret = regmap_read(data->regmap, ADUX1020_REG_INT_STATUS, &status);
 	if (ret < 0)
 		return IRQ_HANDLED;

 	status &= ADUX1020_MODE_INT_STATUS_MASK;

 	if (status & ADUX1020_INT_PROX_ON1) {
 		iio_push_event(indio_dev,
 			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
 						    IIO_EV_TYPE_THRESH,
 						    IIO_EV_DIR_RISING),
 			       iio_get_time_ns(indio_dev));
 	}

 	if (status & ADUX1020_INT_PROX_OFF1) {
 		iio_push_event(indio_dev,
 			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
 						    IIO_EV_TYPE_THRESH,
 						    IIO_EV_DIR_FALLING),
 			       iio_get_time_ns(indio_dev));
 	}

 	regmap_update_bits(data->regmap, ADUX1020_REG_INT_STATUS,
 			   ADUX1020_MODE_INT_MASK, ADUX1020_INT_CLEAR);

 	return IRQ_HANDLED;
 }

 static int adux1020_chip_init(struct adux1020_data *data)
 {
 	struct i2c_client *client = data->client;
 	int ret;
 	unsigned int val;

 	ret = regmap_read(data->regmap, ADUX1020_REG_CHIP_ID, &val);
 	if (ret < 0)
 		return ret;

 	if ((val & ADUX1020_CHIP_ID_MASK) != ADUX1020_CHIP_ID) {
 		dev_err(&client->dev, "invalid chip id 0x%04x\n", val);
 		return -ENODEV;
 	}

 	dev_dbg(&client->dev, "Detected ADUX1020 with chip id: 0x%04x\n", val);

 	ret = regmap_update_bits(data->regmap, ADUX1020_REG_SW_RESET,
 				 ADUX1020_SW_RESET, ADUX1020_SW_RESET);
 	if (ret < 0)
 		return ret;

 	/* Load default configuration */
 	ret = regmap_multi_reg_write(data->regmap, adux1020_def_conf,
 				     ARRAY_SIZE(adux1020_def_conf));
 	if (ret < 0)
 		return ret;

 	ret = adux1020_flush_fifo(data);
 	if (ret < 0)
 		return ret;

 	/* Use LED_IREF for proximity mode */
 	ret = regmap_update_bits(data->regmap, ADUX1020_REG_LED_CURRENT,
 				 ADUX1020_LED_PIREF_EN, 0);
 	if (ret < 0)
 		return ret;

 	/* Mask all interrupts */
 	return regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
 			   ADUX1020_MODE_INT_MASK, ADUX1020_MODE_INT_DISABLE);
 }

 static int adux1020_probe(struct i2c_client *client,
 			  const struct i2c_device_id *id)
 {
 	struct adux1020_data *data;
 	struct iio_dev *indio_dev;
 	int ret;

 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 	if (!indio_dev)
 		return -ENOMEM;

 	indio_dev->dev.parent = &client->dev;
 	indio_dev->info = &adux1020_info;
 	indio_dev->name = ADUX1020_DRV_NAME;
 	indio_dev->channels = adux1020_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adux1020_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	data = iio_priv(indio_dev);

 	data->regmap = devm_regmap_init_i2c(client, &adux1020_regmap_config);
 	if (IS_ERR(data->regmap)) {
 		dev_err(&client->dev, "regmap initialization failed.\n");
 		return PTR_ERR(data->regmap);
 	}

 	data->client = client;
 	data->indio_dev = indio_dev;
 	mutex_init(&data->lock);

 	ret = adux1020_chip_init(data);
 	if (ret)
 		return ret;

 	if (client->irq) {
 		ret = devm_request_threaded_irq(&client->dev, client->irq,
 					NULL, adux1020_interrupt_handler,
 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 					ADUX1020_DRV_NAME, indio_dev);
 		if (ret) {
 			dev_err(&client->dev, "irq request error %d\n", -ret);
 			return ret;
 		}
 	}

 	return devm_iio_device_register(&client->dev, indio_dev);
 }

 static const struct i2c_device_id adux1020_id[] = {
 	{ "adux1020", 0 },
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, adux1020_id);

 static const struct of_device_id adux1020_of_match[] = {
 	{ .compatible = "adi,adux1020" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adux1020_of_match);

 static struct i2c_driver adux1020_driver = {
 	.driver = {
 		.name	= ADUX1020_DRV_NAME,
 		.of_match_table = adux1020_of_match,
 	},
 	.probe		= adux1020_probe,
 	.id_table	= adux1020_id,
 };
 module_i2c_driver(adux1020_driver);

 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
 MODULE_DESCRIPTION("ADUX1020 photometric sensor");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* adux1020.c - Support for Analog Devices ADUX1020 photometric sensor
	*
	* Copyright (C) 2019 Linaro Ltd.
	* Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
	*
	* TODO: Triggered buffer support
	*/

	#include <linux/bitfield.h>
	#include <linux/delay.h>
	#include <linux/err.h>
	#include <linux/i2c.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/regmap.h>

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

	#define ADUX1020_REGMAP_NAME "adux1020_regmap"
	#define ADUX1020_DRV_NAME "adux1020"

	/* System registers */
	#define ADUX1020_REG_CHIP_ID 0x08
	#define ADUX1020_REG_SLAVE_ADDRESS 0x09

	#define ADUX1020_REG_SW_RESET 0x0f
	#define ADUX1020_REG_INT_ENABLE 0x1c
	#define ADUX1020_REG_INT_POLARITY 0x1d
	#define ADUX1020_REG_PROX_TH_ON1 0x2a
	#define ADUX1020_REG_PROX_TH_OFF1 0x2b
	#define ADUX1020_REG_PROX_TYPE 0x2f
	#define ADUX1020_REG_TEST_MODES_3 0x32
	#define ADUX1020_REG_FORCE_MODE 0x33
	#define ADUX1020_REG_FREQUENCY 0x40
	#define ADUX1020_REG_LED_CURRENT 0x41
	#define ADUX1020_REG_OP_MODE 0x45
	#define ADUX1020_REG_INT_MASK 0x48
	#define ADUX1020_REG_INT_STATUS 0x49
	#define ADUX1020_REG_DATA_BUFFER 0x60

	/* Chip ID bits */
	#define ADUX1020_CHIP_ID_MASK GENMASK(11, 0)
	#define ADUX1020_CHIP_ID 0x03fc

	#define ADUX1020_SW_RESET BIT(1)
	#define ADUX1020_FIFO_FLUSH BIT(15)
	#define ADUX1020_OP_MODE_MASK GENMASK(3, 0)
	#define ADUX1020_DATA_OUT_MODE_MASK GENMASK(7, 4)
	#define ADUX1020_DATA_OUT_PROX_I FIELD_PREP(ADUX1020_DATA_OUT_MODE_MASK, 1)

	#define ADUX1020_MODE_INT_MASK GENMASK(7, 0)
	#define ADUX1020_INT_ENABLE 0x2094
	#define ADUX1020_INT_DISABLE 0x2090
	#define ADUX1020_PROX_INT_ENABLE 0x00f0
	#define ADUX1020_PROX_ON1_INT BIT(0)
	#define ADUX1020_PROX_OFF1_INT BIT(1)
	#define ADUX1020_FIFO_INT_ENABLE 0x7f
	#define ADUX1020_MODE_INT_DISABLE 0xff
	#define ADUX1020_MODE_INT_STATUS_MASK GENMASK(7, 0)
	#define ADUX1020_FIFO_STATUS_MASK GENMASK(15, 8)
	#define ADUX1020_INT_CLEAR 0xff
	#define ADUX1020_PROX_TYPE BIT(15)

	#define ADUX1020_INT_PROX_ON1 BIT(0)
	#define ADUX1020_INT_PROX_OFF1 BIT(1)

	#define ADUX1020_FORCE_CLOCK_ON 0x0f4f
	#define ADUX1020_FORCE_CLOCK_RESET 0x0040
	#define ADUX1020_ACTIVE_4_STATE 0x0008

	#define ADUX1020_PROX_FREQ_MASK GENMASK(7, 4)
	#define ADUX1020_PROX_FREQ(x) FIELD_PREP(ADUX1020_PROX_FREQ_MASK, x)

	#define ADUX1020_LED_CURRENT_MASK GENMASK(3, 0)
	#define ADUX1020_LED_PIREF_EN BIT(12)

	/* Operating modes */
	enum adux1020_op_modes {
	ADUX1020_MODE_STANDBY,
	ADUX1020_MODE_PROX_I,
	ADUX1020_MODE_PROX_XY,
	ADUX1020_MODE_GEST,
	ADUX1020_MODE_SAMPLE,
	ADUX1020_MODE_FORCE = 0x0e,
	ADUX1020_MODE_IDLE = 0x0f,
	};

	struct adux1020_data {
	struct i2c_client *client;
	struct iio_dev *indio_dev;
	struct mutex lock;
	struct regmap *regmap;
	};

	struct adux1020_mode_data {
	u8 bytes;
	u8 buf_len;
	u16 int_en;
	};

	static const struct adux1020_mode_data adux1020_modes[] = {
	[ADUX1020_MODE_PROX_I] = {
	.bytes = 2,
	.buf_len = 1,
	.int_en = ADUX1020_PROX_INT_ENABLE,
	},
	};

	static const struct regmap_config adux1020_regmap_config = {
	.name = ADUX1020_REGMAP_NAME,
	.reg_bits = 8,
	.val_bits = 16,
	.max_register = 0x6F,
	.cache_type = REGCACHE_NONE,
	};

	static const struct reg_sequence adux1020_def_conf[] = {
	{ 0x000c, 0x000f },
	{ 0x0010, 0x1010 },
	{ 0x0011, 0x004c },
	{ 0x0012, 0x5f0c },
	{ 0x0013, 0xada5 },
	{ 0x0014, 0x0080 },
	{ 0x0015, 0x0000 },
	{ 0x0016, 0x0600 },
	{ 0x0017, 0x0000 },
	{ 0x0018, 0x2693 },
	{ 0x0019, 0x0004 },
	{ 0x001a, 0x4280 },
	{ 0x001b, 0x0060 },
	{ 0x001c, 0x2094 },
	{ 0x001d, 0x0020 },
	{ 0x001e, 0x0001 },
	{ 0x001f, 0x0100 },
	{ 0x0020, 0x0320 },
	{ 0x0021, 0x0A13 },
	{ 0x0022, 0x0320 },
	{ 0x0023, 0x0113 },
	{ 0x0024, 0x0000 },
	{ 0x0025, 0x2412 },
	{ 0x0026, 0x2412 },
	{ 0x0027, 0x0022 },
	{ 0x0028, 0x0000 },
	{ 0x0029, 0x0300 },
	{ 0x002a, 0x0700 },
	{ 0x002b, 0x0600 },
	{ 0x002c, 0x6000 },
	{ 0x002d, 0x4000 },
	{ 0x002e, 0x0000 },
	{ 0x002f, 0x0000 },
	{ 0x0030, 0x0000 },
	{ 0x0031, 0x0000 },
	{ 0x0032, 0x0040 },
	{ 0x0033, 0x0008 },
	{ 0x0034, 0xE400 },
	{ 0x0038, 0x8080 },
	{ 0x0039, 0x8080 },
	{ 0x003a, 0x2000 },
	{ 0x003b, 0x1f00 },
	{ 0x003c, 0x2000 },
	{ 0x003d, 0x2000 },
	{ 0x003e, 0x0000 },
	{ 0x0040, 0x8069 },
	{ 0x0041, 0x1f2f },
	{ 0x0042, 0x4000 },
	{ 0x0043, 0x0000 },
	{ 0x0044, 0x0008 },
	{ 0x0046, 0x0000 },
	{ 0x0048, 0x00ef },
	{ 0x0049, 0x0000 },
	{ 0x0045, 0x0000 },
	};

	static const int adux1020_rates[][2] = {
	{ 0, 100000 },
	{ 0, 200000 },
	{ 0, 500000 },
	{ 1, 0 },
	{ 2, 0 },
	{ 5, 0 },
	{ 10, 0 },
	{ 20, 0 },
	{ 50, 0 },
	{ 100, 0 },
	{ 190, 0 },
	{ 450, 0 },
	{ 820, 0 },
	{ 1400, 0 },
	};

	static const int adux1020_led_currents[][2] = {
	{ 0, 25000 },
	{ 0, 40000 },
	{ 0, 55000 },
	{ 0, 70000 },
	{ 0, 85000 },
	{ 0, 100000 },
	{ 0, 115000 },
	{ 0, 130000 },
	{ 0, 145000 },
	{ 0, 160000 },
	{ 0, 175000 },
	{ 0, 190000 },
	{ 0, 205000 },
	{ 0, 220000 },
	{ 0, 235000 },
	{ 0, 250000 },
	};

	static int adux1020_flush_fifo(struct adux1020_data *data)
	{
	int ret;

	/* Force Idle mode */
	ret = regmap_write(data->regmap, ADUX1020_REG_FORCE_MODE,
	ADUX1020_ACTIVE_4_STATE);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
	ADUX1020_OP_MODE_MASK, ADUX1020_MODE_FORCE);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
	ADUX1020_OP_MODE_MASK, ADUX1020_MODE_IDLE);
	if (ret < 0)
	return ret;

	/* Flush FIFO */
	ret = regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
	ADUX1020_FORCE_CLOCK_ON);
	if (ret < 0)
	return ret;

	ret = regmap_write(data->regmap, ADUX1020_REG_INT_STATUS,
	ADUX1020_FIFO_FLUSH);
	if (ret < 0)
	return ret;

	return regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
	ADUX1020_FORCE_CLOCK_RESET);
	}

	static int adux1020_read_fifo(struct adux1020_data data, u16 buf, u8 buf_len)
	{
	unsigned int regval;
	int i, ret;

	/* Enable 32MHz clock */
	ret = regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
	ADUX1020_FORCE_CLOCK_ON);
	if (ret < 0)
	return ret;

	for (i = 0; i < buf_len; i++) {
	ret = regmap_read(data->regmap, ADUX1020_REG_DATA_BUFFER,
	&regval);
	if (ret < 0)
	return ret;

	buf[i] = regval;
	}

	/* Set 32MHz clock to be controlled by internal state machine */
	return regmap_write(data->regmap, ADUX1020_REG_TEST_MODES_3,
	ADUX1020_FORCE_CLOCK_RESET);
	}

	static int adux1020_set_mode(struct adux1020_data *data,
	enum adux1020_op_modes mode)
	{
	int ret;

	/* Switch to standby mode before changing the mode */
	ret = regmap_write(data->regmap, ADUX1020_REG_OP_MODE,
	ADUX1020_MODE_STANDBY);
	if (ret < 0)
	return ret;

	/* Set data out and switch to the desired mode */
	switch (mode) {
	case ADUX1020_MODE_PROX_I:
	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
	ADUX1020_DATA_OUT_MODE_MASK,
	ADUX1020_DATA_OUT_PROX_I);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(data->regmap, ADUX1020_REG_OP_MODE,
	ADUX1020_OP_MODE_MASK,
	ADUX1020_MODE_PROX_I);
	if (ret < 0)
	return ret;
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	static int adux1020_measure(struct adux1020_data *data,
	enum adux1020_op_modes mode,
	u16 *val)
	{
	unsigned int status;
	int ret, tries = 50;

	/* Disable INT pin as polling is going to be used */
	ret = regmap_write(data->regmap, ADUX1020_REG_INT_ENABLE,
	ADUX1020_INT_DISABLE);
	if (ret < 0)
	return ret;

	/* Enable mode interrupt */
	ret = regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
	ADUX1020_MODE_INT_MASK,
	adux1020_modes[mode].int_en);
	if (ret < 0)
	return ret;

	while (tries--) {
	ret = regmap_read(data->regmap, ADUX1020_REG_INT_STATUS,
	&status);
	if (ret < 0)
	return ret;

	status &= ADUX1020_FIFO_STATUS_MASK;
	if (status >= adux1020_modes[mode].bytes)
	break;
	msleep(20);
	}

	if (tries < 0)
	return -EIO;

	ret = adux1020_read_fifo(data, val, adux1020_modes[mode].buf_len);
	if (ret < 0)
	return ret;

	/* Clear mode interrupt */
	ret = regmap_write(data->regmap, ADUX1020_REG_INT_STATUS,
	(~adux1020_modes[mode].int_en));
	if (ret < 0)
	return ret;

	/* Disable mode interrupts */
	return regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
	ADUX1020_MODE_INT_MASK,
	ADUX1020_MODE_INT_DISABLE);
	}

	static int adux1020_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct adux1020_data *data = iio_priv(indio_dev);
	u16 buf[3];
	int ret = -EINVAL;
	unsigned int regval;

	mutex_lock(&data->lock);

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	switch (chan->type) {
	case IIO_PROXIMITY:
	ret = adux1020_set_mode(data, ADUX1020_MODE_PROX_I);
	if (ret < 0)
	goto fail;

	ret = adux1020_measure(data, ADUX1020_MODE_PROX_I, buf);
	if (ret < 0)
	goto fail;

	*val = buf[0];
	ret = IIO_VAL_INT;
	break;
	default:
	break;
	}
	break;
	case IIO_CHAN_INFO_PROCESSED:
	switch (chan->type) {
	case IIO_CURRENT:
	ret = regmap_read(data->regmap,
	ADUX1020_REG_LED_CURRENT, &regval);
	if (ret < 0)
	goto fail;

	regval = regval & ADUX1020_LED_CURRENT_MASK;

	*val = adux1020_led_currents[regval][0];
	*val2 = adux1020_led_currents[regval][1];

	ret = IIO_VAL_INT_PLUS_MICRO;
	break;
	default:
	break;
	}
	break;
	case IIO_CHAN_INFO_SAMP_FREQ:
	switch (chan->type) {
	case IIO_PROXIMITY:
	ret = regmap_read(data->regmap, ADUX1020_REG_FREQUENCY,
	&regval);
	if (ret < 0)
	goto fail;

	regval = FIELD_GET(ADUX1020_PROX_FREQ_MASK, regval);

	*val = adux1020_rates[regval][0];
	*val2 = adux1020_rates[regval][1];

	ret = IIO_VAL_INT_PLUS_MICRO;
	break;
	default:
	break;
	}
	break;
	default:
	break;
	}

	fail:
	mutex_unlock(&data->lock);

	return ret;
	};

	static inline int adux1020_find_index(const int array[][2], int count, int val,
	int val2)
	{
	int i;

	for (i = 0; i < count; i++)
	if (val == array[i][0] && val2 == array[i][1])
	return i;

	return -EINVAL;
	}

	static int adux1020_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct adux1020_data *data = iio_priv(indio_dev);
	int i, ret = -EINVAL;

	mutex_lock(&data->lock);

	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
	if (chan->type == IIO_PROXIMITY) {
	i = adux1020_find_index(adux1020_rates,
	ARRAY_SIZE(adux1020_rates),
	val, val2);
	if (i < 0) {
	ret = i;
	goto fail;
	}

	ret = regmap_update_bits(data->regmap,
	ADUX1020_REG_FREQUENCY,
	ADUX1020_PROX_FREQ_MASK,
	ADUX1020_PROX_FREQ(i));
	}
	break;
	case IIO_CHAN_INFO_PROCESSED:
	if (chan->type == IIO_CURRENT) {
	i = adux1020_find_index(adux1020_led_currents,
	ARRAY_SIZE(adux1020_led_currents),
	val, val2);
	if (i < 0) {
	ret = i;
	goto fail;
	}

	ret = regmap_update_bits(data->regmap,
	ADUX1020_REG_LED_CURRENT,
	ADUX1020_LED_CURRENT_MASK, i);
	}
	break;
	default:
	break;
	}

	fail:
	mutex_unlock(&data->lock);

	return ret;
	}

	static int adux1020_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 adux1020_data *data = iio_priv(indio_dev);
	int ret, mask;

	mutex_lock(&data->lock);

	ret = regmap_write(data->regmap, ADUX1020_REG_INT_ENABLE,
	ADUX1020_INT_ENABLE);
	if (ret < 0)
	goto fail;

	ret = regmap_write(data->regmap, ADUX1020_REG_INT_POLARITY, 0);
	if (ret < 0)
	goto fail;

	switch (chan->type) {
	case IIO_PROXIMITY:
	if (dir == IIO_EV_DIR_RISING)
	mask = ADUX1020_PROX_ON1_INT;
	else
	mask = ADUX1020_PROX_OFF1_INT;

	if (state)
	state = 0;
	else
	state = mask;

	ret = regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
	mask, state);
	if (ret < 0)
	goto fail;

	/*
	* Trigger proximity interrupt when the intensity is above
	* or below threshold
	*/
	ret = regmap_update_bits(data->regmap, ADUX1020_REG_PROX_TYPE,
	ADUX1020_PROX_TYPE,
	ADUX1020_PROX_TYPE);
	if (ret < 0)
	goto fail;

	/* Set proximity mode */
	ret = adux1020_set_mode(data, ADUX1020_MODE_PROX_I);
	break;
	default:
	ret = -EINVAL;
	break;
	}

	fail:
	mutex_unlock(&data->lock);

	return ret;
	}

	static int adux1020_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 adux1020_data *data = iio_priv(indio_dev);
	int ret, mask;
	unsigned int regval;

	switch (chan->type) {
	case IIO_PROXIMITY:
	if (dir == IIO_EV_DIR_RISING)
	mask = ADUX1020_PROX_ON1_INT;
	else
	mask = ADUX1020_PROX_OFF1_INT;
	break;
	default:
	return -EINVAL;
	}

	ret = regmap_read(data->regmap, ADUX1020_REG_INT_MASK, &regval);
	if (ret < 0)
	return ret;

	return !(regval & mask);
	}

	static int adux1020_read_thresh(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan,
	enum iio_event_type type,
	enum iio_event_direction dir,
	enum iio_event_info info, int val, int val2)
	{
	struct adux1020_data *data = iio_priv(indio_dev);
	u8 reg;
	int ret;
	unsigned int regval;

	switch (chan->type) {
	case IIO_PROXIMITY:
	if (dir == IIO_EV_DIR_RISING)
	reg = ADUX1020_REG_PROX_TH_ON1;
	else
	reg = ADUX1020_REG_PROX_TH_OFF1;
	break;
	default:
	return -EINVAL;
	}

	ret = regmap_read(data->regmap, reg, &regval);
	if (ret < 0)
	return ret;

	*val = regval;

	return IIO_VAL_INT;
	}

	static int adux1020_write_thresh(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan,
	enum iio_event_type type,
	enum iio_event_direction dir,
	enum iio_event_info info, int val, int val2)
	{
	struct adux1020_data *data = iio_priv(indio_dev);
	u8 reg;

	switch (chan->type) {
	case IIO_PROXIMITY:
	if (dir == IIO_EV_DIR_RISING)
	reg = ADUX1020_REG_PROX_TH_ON1;
	else
	reg = ADUX1020_REG_PROX_TH_OFF1;
	break;
	default:
	return -EINVAL;
	}

	/* Full scale threshold value is 0-65535 */
	if (val < 0 \|\| val > 65535)
	return -EINVAL;

	return regmap_write(data->regmap, reg, val);
	}

	static const struct iio_event_spec adux1020_proximity_event[] = {
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_RISING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_FALLING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	};

	static const struct iio_chan_spec adux1020_channels[] = {
	{
	.type = IIO_PROXIMITY,
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
	BIT(IIO_CHAN_INFO_SAMP_FREQ),
	.event_spec = adux1020_proximity_event,
	.num_event_specs = ARRAY_SIZE(adux1020_proximity_event),
	},
	{
	.type = IIO_CURRENT,
	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
	.extend_name = "led",
	.output = 1,
	},
	};

	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
	"0.1 0.2 0.5 1 2 5 10 20 50 100 190 450 820 1400");

	static struct attribute *adux1020_attributes[] = {
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	NULL
	};

	static const struct attribute_group adux1020_attribute_group = {
	.attrs = adux1020_attributes,
	};

	static const struct iio_info adux1020_info = {
	.attrs = &adux1020_attribute_group,
	.read_raw = adux1020_read_raw,
	.write_raw = adux1020_write_raw,
	.read_event_config = adux1020_read_event_config,
	.write_event_config = adux1020_write_event_config,
	.read_event_value = adux1020_read_thresh,
	.write_event_value = adux1020_write_thresh,
	};

	static irqreturn_t adux1020_interrupt_handler(int irq, void *private)
	{
	struct iio_dev *indio_dev = private;
	struct adux1020_data *data = iio_priv(indio_dev);
	int ret, status;

	ret = regmap_read(data->regmap, ADUX1020_REG_INT_STATUS, &status);
	if (ret < 0)
	return IRQ_HANDLED;

	status &= ADUX1020_MODE_INT_STATUS_MASK;

	if (status & ADUX1020_INT_PROX_ON1) {
	iio_push_event(indio_dev,
	IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_RISING),
	iio_get_time_ns(indio_dev));
	}

	if (status & ADUX1020_INT_PROX_OFF1) {
	iio_push_event(indio_dev,
	IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_FALLING),
	iio_get_time_ns(indio_dev));
	}

	regmap_update_bits(data->regmap, ADUX1020_REG_INT_STATUS,
	ADUX1020_MODE_INT_MASK, ADUX1020_INT_CLEAR);

	return IRQ_HANDLED;
	}

	static int adux1020_chip_init(struct adux1020_data *data)
	{
	struct i2c_client *client = data->client;
	int ret;
	unsigned int val;

	ret = regmap_read(data->regmap, ADUX1020_REG_CHIP_ID, &val);
	if (ret < 0)
	return ret;

	if ((val & ADUX1020_CHIP_ID_MASK) != ADUX1020_CHIP_ID) {
	dev_err(&client->dev, "invalid chip id 0x%04x\n", val);
	return -ENODEV;
	}

	dev_dbg(&client->dev, "Detected ADUX1020 with chip id: 0x%04x\n", val);

	ret = regmap_update_bits(data->regmap, ADUX1020_REG_SW_RESET,
	ADUX1020_SW_RESET, ADUX1020_SW_RESET);
	if (ret < 0)
	return ret;

	/* Load default configuration */
	ret = regmap_multi_reg_write(data->regmap, adux1020_def_conf,
	ARRAY_SIZE(adux1020_def_conf));
	if (ret < 0)
	return ret;

	ret = adux1020_flush_fifo(data);
	if (ret < 0)
	return ret;

	/* Use LED_IREF for proximity mode */
	ret = regmap_update_bits(data->regmap, ADUX1020_REG_LED_CURRENT,
	ADUX1020_LED_PIREF_EN, 0);
	if (ret < 0)
	return ret;

	/* Mask all interrupts */
	return regmap_update_bits(data->regmap, ADUX1020_REG_INT_MASK,
	ADUX1020_MODE_INT_MASK, ADUX1020_MODE_INT_DISABLE);
	}

	static int adux1020_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct adux1020_data *data;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (!indio_dev)
	return -ENOMEM;

	indio_dev->dev.parent = &client->dev;
	indio_dev->info = &adux1020_info;
	indio_dev->name = ADUX1020_DRV_NAME;
	indio_dev->channels = adux1020_channels;
	indio_dev->num_channels = ARRAY_SIZE(adux1020_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;

	data = iio_priv(indio_dev);

	data->regmap = devm_regmap_init_i2c(client, &adux1020_regmap_config);
	if (IS_ERR(data->regmap)) {
	dev_err(&client->dev, "regmap initialization failed.\n");
	return PTR_ERR(data->regmap);
	}

	data->client = client;
	data->indio_dev = indio_dev;
	mutex_init(&data->lock);

	ret = adux1020_chip_init(data);
	if (ret)
	return ret;

	if (client->irq) {
	ret = devm_request_threaded_irq(&client->dev, client->irq,
	NULL, adux1020_interrupt_handler,
	IRQF_TRIGGER_HIGH \| IRQF_ONESHOT,
	ADUX1020_DRV_NAME, indio_dev);
	if (ret) {
	dev_err(&client->dev, "irq request error %d\n", -ret);
	return ret;
	}
	}

	return devm_iio_device_register(&client->dev, indio_dev);
	}

	static const struct i2c_device_id adux1020_id[] = {
	{ "adux1020", 0 },
	{}
	};
	MODULE_DEVICE_TABLE(i2c, adux1020_id);

	static const struct of_device_id adux1020_of_match[] = {
	{ .compatible = "adi,adux1020" },
	{ }
	};
	MODULE_DEVICE_TABLE(of, adux1020_of_match);

	static struct i2c_driver adux1020_driver = {
	.driver = {
	.name = ADUX1020_DRV_NAME,
	.of_match_table = adux1020_of_match,
	},
	.probe = adux1020_probe,
	.id_table = adux1020_id,
	};
	module_i2c_driver(adux1020_driver);

	MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
	MODULE_DESCRIPTION("ADUX1020 photometric sensor");
	MODULE_LICENSE("GPL");