drivers/iio/adc/ad7091r-base.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * AD7091RX Analog to Digital converter driver
  *
  * Copyright 2014-2019 Analog Devices Inc.
  */

 #include <linux/bitops.h>
 #include <linux/bitfield.h>
 #include <linux/iio/events.h>
 #include <linux/iio/iio.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>

 #include "ad7091r-base.h"

 const struct iio_event_spec ad7091r_events[] = {
 	{
 		.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),
 	},
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_EITHER,
 		.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
 	},
 };
 EXPORT_SYMBOL_NS_GPL(ad7091r_events, "IIO_AD7091R");

 static int ad7091r_set_channel(struct ad7091r_state *st, unsigned int channel)
 {
 	unsigned int dummy;
 	int ret;

 	/* AD7091R_REG_CHANNEL specified which channels to be converted */
 	ret = regmap_write(st->map, AD7091R_REG_CHANNEL,
 			BIT(channel) | (BIT(channel) << 8));
 	if (ret)
 		return ret;

 	/*
 	 * There is a latency of one conversion before the channel conversion
 	 * sequence is updated
 	 */
 	return regmap_read(st->map, AD7091R_REG_RESULT, &dummy);
 }

 static int ad7091r_read_one(struct iio_dev *iio_dev,
 		unsigned int channel, unsigned int *read_val)
 {
 	struct ad7091r_state *st = iio_priv(iio_dev);
 	unsigned int val;
 	int ret;

 	ret = ad7091r_set_channel(st, channel);
 	if (ret)
 		return ret;

 	ret = regmap_read(st->map, AD7091R_REG_RESULT, &val);
 	if (ret)
 		return ret;

 	if (st->chip_info->reg_result_chan_id(val) != channel)
 		return -EIO;

 	*read_val = AD7091R_REG_RESULT_CONV_RESULT(val);

 	return 0;
 }

 static int ad7091r_read_raw(struct iio_dev *iio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long m)
 {
 	struct ad7091r_state *st = iio_priv(iio_dev);
 	unsigned int read_val;
 	int ret;

 	guard(mutex)(&st->lock);

 	switch (m) {
 	case IIO_CHAN_INFO_RAW:
 		if (st->mode != AD7091R_MODE_COMMAND)
 			return -EBUSY;

 		ret = ad7091r_read_one(iio_dev, chan->channel, &read_val);
 		if (ret)
 			return ret;

 		*val = read_val;
 		return IIO_VAL_INT;

 	case IIO_CHAN_INFO_SCALE:
 		if (st->vref) {
 			ret = regulator_get_voltage(st->vref);
 			if (ret < 0)
 				return ret;

 			*val = ret / 1000;
 		} else {
 			*val = st->chip_info->vref_mV;
 		}

 		*val2 = chan->scan_type.realbits;
 		return IIO_VAL_FRACTIONAL_LOG2;

 	default:
 		return -EINVAL;
 	}
 }

 static int ad7091r_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 ad7091r_state *st = iio_priv(indio_dev);
 	int val, ret;

 	switch (dir) {
 	case IIO_EV_DIR_RISING:
 		ret = regmap_read(st->map,
 				  AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
 				  &val);
 		if (ret)
 			return ret;
 		return val != AD7091R_HIGH_LIMIT;
 	case IIO_EV_DIR_FALLING:
 		ret = regmap_read(st->map,
 				  AD7091R_REG_CH_LOW_LIMIT(chan->channel),
 				  &val);
 		if (ret)
 			return ret;
 		return val != AD7091R_LOW_LIMIT;
 	default:
 		return -EINVAL;
 	}
 }

 static int ad7091r_write_event_config(struct iio_dev *indio_dev,
 				      const struct iio_chan_spec *chan,
 				      enum iio_event_type type,
 				      enum iio_event_direction dir,
 				      bool state)
 {
 	struct ad7091r_state *st = iio_priv(indio_dev);

 	if (state) {
 		return regmap_set_bits(st->map, AD7091R_REG_CONF,
 				       AD7091R_REG_CONF_ALERT_EN);
 	} else {
 		/*
 		 * Set thresholds either to 0 or to 2^12 - 1 as appropriate to
 		 * prevent alerts and thus disable event generation.
 		 */
 		switch (dir) {
 		case IIO_EV_DIR_RISING:
 			return regmap_write(st->map,
 					    AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
 					    AD7091R_HIGH_LIMIT);
 		case IIO_EV_DIR_FALLING:
 			return regmap_write(st->map,
 					    AD7091R_REG_CH_LOW_LIMIT(chan->channel),
 					    AD7091R_LOW_LIMIT);
 		default:
 			return -EINVAL;
 		}
 	}
 }

 static int ad7091r_read_event_value(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 ad7091r_state *st = iio_priv(indio_dev);
 	int ret;

 	switch (info) {
 	case IIO_EV_INFO_VALUE:
 		switch (dir) {
 		case IIO_EV_DIR_RISING:
 			ret = regmap_read(st->map,
 					  AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
 					  val);
 			if (ret)
 				return ret;
 			return IIO_VAL_INT;
 		case IIO_EV_DIR_FALLING:
 			ret = regmap_read(st->map,
 					  AD7091R_REG_CH_LOW_LIMIT(chan->channel),
 					  val);
 			if (ret)
 				return ret;
 			return IIO_VAL_INT;
 		default:
 			return -EINVAL;
 		}
 	case IIO_EV_INFO_HYSTERESIS:
 		ret = regmap_read(st->map,
 				  AD7091R_REG_CH_HYSTERESIS(chan->channel),
 				  val);
 		if (ret)
 			return ret;
 		return IIO_VAL_INT;
 	default:
 		return -EINVAL;
 	}
 }

 static int ad7091r_write_event_value(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 ad7091r_state *st = iio_priv(indio_dev);

 	switch (info) {
 	case IIO_EV_INFO_VALUE:
 		switch (dir) {
 		case IIO_EV_DIR_RISING:
 			return regmap_write(st->map,
 					    AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
 					    val);
 		case IIO_EV_DIR_FALLING:
 			return regmap_write(st->map,
 					    AD7091R_REG_CH_LOW_LIMIT(chan->channel),
 					    val);
 		default:
 			return -EINVAL;
 		}
 	case IIO_EV_INFO_HYSTERESIS:
 		return regmap_write(st->map,
 				    AD7091R_REG_CH_HYSTERESIS(chan->channel),
 				    val);
 	default:
 		return -EINVAL;
 	}
 }

 static const struct iio_info ad7091r_info = {
 	.read_raw = ad7091r_read_raw,
 	.read_event_config = &ad7091r_read_event_config,
 	.write_event_config = &ad7091r_write_event_config,
 	.read_event_value = &ad7091r_read_event_value,
 	.write_event_value = &ad7091r_write_event_value,
 };

 static irqreturn_t ad7091r_event_handler(int irq, void *private)
 {
 	struct iio_dev *iio_dev = private;
 	struct ad7091r_state *st = iio_priv(iio_dev);
 	unsigned int i, read_val;
 	int ret;
 	s64 timestamp = iio_get_time_ns(iio_dev);

 	ret = regmap_read(st->map, AD7091R_REG_ALERT, &read_val);
 	if (ret)
 		return IRQ_HANDLED;

 	for (i = 0; i < st->chip_info->num_channels; i++) {
 		if (read_val & BIT(i * 2))
 			iio_push_event(iio_dev,
 					IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
 						IIO_EV_TYPE_THRESH,
 						IIO_EV_DIR_RISING), timestamp);
 		if (read_val & BIT(i * 2 + 1))
 			iio_push_event(iio_dev,
 					IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
 						IIO_EV_TYPE_THRESH,
 						IIO_EV_DIR_FALLING), timestamp);
 	}

 	return IRQ_HANDLED;
 }

 static void ad7091r_remove(void *data)
 {
 	struct ad7091r_state *st = data;

 	regulator_disable(st->vref);
 }

 int ad7091r_probe(struct device *dev, const struct ad7091r_init_info *init_info,
 		  int irq)
 {
 	struct iio_dev *iio_dev;
 	struct ad7091r_state *st;
 	int ret;

 	iio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 	if (!iio_dev)
 		return -ENOMEM;

 	st = iio_priv(iio_dev);
 	st->dev = dev;
 	init_info->init_adc_regmap(st, init_info->regmap_config);
 	if (IS_ERR(st->map))
 		return dev_err_probe(st->dev, PTR_ERR(st->map),
 				     "Error initializing regmap\n");

 	iio_dev->info = &ad7091r_info;
 	iio_dev->modes = INDIO_DIRECT_MODE;

 	if (init_info->setup) {
 		ret = init_info->setup(st);
 		if (ret < 0)
 			return ret;
 	}

 	if (irq) {
 		st->chip_info = init_info->info_irq;
 		ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
 					 AD7091R_REG_CONF_ALERT_EN, BIT(4));
 		if (ret)
 			return ret;

 		ret = devm_request_threaded_irq(dev, irq, NULL,
 						ad7091r_event_handler,
 						IRQF_TRIGGER_FALLING |
 						IRQF_ONESHOT,
 						st->chip_info->name, iio_dev);
 		if (ret)
 			return ret;
 	} else {
 		st->chip_info = init_info->info_no_irq;
 	}

 	iio_dev->name = st->chip_info->name;
 	iio_dev->num_channels = st->chip_info->num_channels;
 	iio_dev->channels = st->chip_info->channels;

 	st->vref = devm_regulator_get_optional(dev, "vref");
 	if (IS_ERR(st->vref)) {
 		if (PTR_ERR(st->vref) == -EPROBE_DEFER)
 			return -EPROBE_DEFER;

 		st->vref = NULL;
 		/* Enable internal vref */
 		ret = regmap_set_bits(st->map, AD7091R_REG_CONF,
 				      AD7091R_REG_CONF_INT_VREF);
 		if (ret)
 			return dev_err_probe(st->dev, ret,
 					     "Error on enable internal reference\n");
 	} else {
 		ret = regulator_enable(st->vref);
 		if (ret)
 			return ret;
 		ret = devm_add_action_or_reset(dev, ad7091r_remove, st);
 		if (ret)
 			return ret;
 	}

 	/* Use command mode by default to convert only desired channels*/
 	ret = st->chip_info->set_mode(st, AD7091R_MODE_COMMAND);
 	if (ret)
 		return ret;

 	return devm_iio_device_register(dev, iio_dev);
 }
 EXPORT_SYMBOL_NS_GPL(ad7091r_probe, "IIO_AD7091R");

 bool ad7091r_writeable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case AD7091R_REG_RESULT:
 	case AD7091R_REG_ALERT:
 		return false;
 	default:
 		return true;
 	}
 }
 EXPORT_SYMBOL_NS_GPL(ad7091r_writeable_reg, "IIO_AD7091R");

 bool ad7091r_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case AD7091R_REG_RESULT:
 	case AD7091R_REG_ALERT:
 		return true;
 	default:
 		return false;
 	}
 }
 EXPORT_SYMBOL_NS_GPL(ad7091r_volatile_reg, "IIO_AD7091R");

 MODULE_AUTHOR("Beniamin Bia <beniamin.bia@analog.com>");
 MODULE_DESCRIPTION("Analog Devices AD7091Rx multi-channel converters");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* AD7091RX Analog to Digital converter driver
	*
	* Copyright 2014-2019 Analog Devices Inc.
	*/

	#include <linux/bitops.h>
	#include <linux/bitfield.h>
	#include <linux/iio/events.h>
	#include <linux/iio/iio.h>
	#include <linux/interrupt.h>
	#include <linux/module.h>
	#include <linux/regmap.h>
	#include <linux/regulator/consumer.h>

	#include "ad7091r-base.h"

	const struct iio_event_spec ad7091r_events[] = {
	{
	.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),
	},
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_EITHER,
	.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
	},
	};
	EXPORT_SYMBOL_NS_GPL(ad7091r_events, "IIO_AD7091R");

	static int ad7091r_set_channel(struct ad7091r_state *st, unsigned int channel)
	{
	unsigned int dummy;
	int ret;

	/* AD7091R_REG_CHANNEL specified which channels to be converted */
	ret = regmap_write(st->map, AD7091R_REG_CHANNEL,
	BIT(channel) \| (BIT(channel) << 8));
	if (ret)
	return ret;

	/*
	* There is a latency of one conversion before the channel conversion
	* sequence is updated
	*/
	return regmap_read(st->map, AD7091R_REG_RESULT, &dummy);
	}

	static int ad7091r_read_one(struct iio_dev *iio_dev,
	unsigned int channel, unsigned int *read_val)
	{
	struct ad7091r_state *st = iio_priv(iio_dev);
	unsigned int val;
	int ret;

	ret = ad7091r_set_channel(st, channel);
	if (ret)
	return ret;

	ret = regmap_read(st->map, AD7091R_REG_RESULT, &val);
	if (ret)
	return ret;

	if (st->chip_info->reg_result_chan_id(val) != channel)
	return -EIO;

	*read_val = AD7091R_REG_RESULT_CONV_RESULT(val);

	return 0;
	}

	static int ad7091r_read_raw(struct iio_dev *iio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long m)
	{
	struct ad7091r_state *st = iio_priv(iio_dev);
	unsigned int read_val;
	int ret;

	guard(mutex)(&st->lock);

	switch (m) {
	case IIO_CHAN_INFO_RAW:
	if (st->mode != AD7091R_MODE_COMMAND)
	return -EBUSY;

	ret = ad7091r_read_one(iio_dev, chan->channel, &read_val);
	if (ret)
	return ret;

	*val = read_val;
	return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:
	if (st->vref) {
	ret = regulator_get_voltage(st->vref);
	if (ret < 0)
	return ret;

	*val = ret / 1000;
	} else {
	*val = st->chip_info->vref_mV;
	}

	*val2 = chan->scan_type.realbits;
	return IIO_VAL_FRACTIONAL_LOG2;

	default:
	return -EINVAL;
	}
	}

	static int ad7091r_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 ad7091r_state *st = iio_priv(indio_dev);
	int val, ret;

	switch (dir) {
	case IIO_EV_DIR_RISING:
	ret = regmap_read(st->map,
	AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
	&val);
	if (ret)
	return ret;
	return val != AD7091R_HIGH_LIMIT;
	case IIO_EV_DIR_FALLING:
	ret = regmap_read(st->map,
	AD7091R_REG_CH_LOW_LIMIT(chan->channel),
	&val);
	if (ret)
	return ret;
	return val != AD7091R_LOW_LIMIT;
	default:
	return -EINVAL;
	}
	}

	static int ad7091r_write_event_config(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan,
	enum iio_event_type type,
	enum iio_event_direction dir,
	bool state)
	{
	struct ad7091r_state *st = iio_priv(indio_dev);

	if (state) {
	return regmap_set_bits(st->map, AD7091R_REG_CONF,
	AD7091R_REG_CONF_ALERT_EN);
	} else {
	/*
	* Set thresholds either to 0 or to 2^12 - 1 as appropriate to
	* prevent alerts and thus disable event generation.
	*/
	switch (dir) {
	case IIO_EV_DIR_RISING:
	return regmap_write(st->map,
	AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
	AD7091R_HIGH_LIMIT);
	case IIO_EV_DIR_FALLING:
	return regmap_write(st->map,
	AD7091R_REG_CH_LOW_LIMIT(chan->channel),
	AD7091R_LOW_LIMIT);
	default:
	return -EINVAL;
	}
	}
	}

	static int ad7091r_read_event_value(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 ad7091r_state *st = iio_priv(indio_dev);
	int ret;

	switch (info) {
	case IIO_EV_INFO_VALUE:
	switch (dir) {
	case IIO_EV_DIR_RISING:
	ret = regmap_read(st->map,
	AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
	val);
	if (ret)
	return ret;
	return IIO_VAL_INT;
	case IIO_EV_DIR_FALLING:
	ret = regmap_read(st->map,
	AD7091R_REG_CH_LOW_LIMIT(chan->channel),
	val);
	if (ret)
	return ret;
	return IIO_VAL_INT;
	default:
	return -EINVAL;
	}
	case IIO_EV_INFO_HYSTERESIS:
	ret = regmap_read(st->map,
	AD7091R_REG_CH_HYSTERESIS(chan->channel),
	val);
	if (ret)
	return ret;
	return IIO_VAL_INT;
	default:
	return -EINVAL;
	}
	}

	static int ad7091r_write_event_value(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 ad7091r_state *st = iio_priv(indio_dev);

	switch (info) {
	case IIO_EV_INFO_VALUE:
	switch (dir) {
	case IIO_EV_DIR_RISING:
	return regmap_write(st->map,
	AD7091R_REG_CH_HIGH_LIMIT(chan->channel),
	val);
	case IIO_EV_DIR_FALLING:
	return regmap_write(st->map,
	AD7091R_REG_CH_LOW_LIMIT(chan->channel),
	val);
	default:
	return -EINVAL;
	}
	case IIO_EV_INFO_HYSTERESIS:
	return regmap_write(st->map,
	AD7091R_REG_CH_HYSTERESIS(chan->channel),
	val);
	default:
	return -EINVAL;
	}
	}

	static const struct iio_info ad7091r_info = {
	.read_raw = ad7091r_read_raw,
	.read_event_config = &ad7091r_read_event_config,
	.write_event_config = &ad7091r_write_event_config,
	.read_event_value = &ad7091r_read_event_value,
	.write_event_value = &ad7091r_write_event_value,
	};

	static irqreturn_t ad7091r_event_handler(int irq, void *private)
	{
	struct iio_dev *iio_dev = private;
	struct ad7091r_state *st = iio_priv(iio_dev);
	unsigned int i, read_val;
	int ret;
	s64 timestamp = iio_get_time_ns(iio_dev);

	ret = regmap_read(st->map, AD7091R_REG_ALERT, &read_val);
	if (ret)
	return IRQ_HANDLED;

	for (i = 0; i < st->chip_info->num_channels; i++) {
	if (read_val & BIT(i * 2))
	iio_push_event(iio_dev,
	IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_RISING), timestamp);
	if (read_val & BIT(i * 2 + 1))
	iio_push_event(iio_dev,
	IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_FALLING), timestamp);
	}

	return IRQ_HANDLED;
	}

	static void ad7091r_remove(void *data)
	{
	struct ad7091r_state *st = data;

	regulator_disable(st->vref);
	}

	int ad7091r_probe(struct device dev, const struct ad7091r_init_info init_info,
	int irq)
	{
	struct iio_dev *iio_dev;
	struct ad7091r_state *st;
	int ret;

	iio_dev = devm_iio_device_alloc(dev, sizeof(*st));
	if (!iio_dev)
	return -ENOMEM;

	st = iio_priv(iio_dev);
	st->dev = dev;
	init_info->init_adc_regmap(st, init_info->regmap_config);
	if (IS_ERR(st->map))
	return dev_err_probe(st->dev, PTR_ERR(st->map),
	"Error initializing regmap\n");

	iio_dev->info = &ad7091r_info;
	iio_dev->modes = INDIO_DIRECT_MODE;

	if (init_info->setup) {
	ret = init_info->setup(st);
	if (ret < 0)
	return ret;
	}

	if (irq) {
	st->chip_info = init_info->info_irq;
	ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
	AD7091R_REG_CONF_ALERT_EN, BIT(4));
	if (ret)
	return ret;

	ret = devm_request_threaded_irq(dev, irq, NULL,
	ad7091r_event_handler,
	IRQF_TRIGGER_FALLING \|
	IRQF_ONESHOT,
	st->chip_info->name, iio_dev);
	if (ret)
	return ret;
	} else {
	st->chip_info = init_info->info_no_irq;
	}

	iio_dev->name = st->chip_info->name;
	iio_dev->num_channels = st->chip_info->num_channels;
	iio_dev->channels = st->chip_info->channels;

	st->vref = devm_regulator_get_optional(dev, "vref");
	if (IS_ERR(st->vref)) {
	if (PTR_ERR(st->vref) == -EPROBE_DEFER)
	return -EPROBE_DEFER;

	st->vref = NULL;
	/* Enable internal vref */
	ret = regmap_set_bits(st->map, AD7091R_REG_CONF,
	AD7091R_REG_CONF_INT_VREF);
	if (ret)
	return dev_err_probe(st->dev, ret,
	"Error on enable internal reference\n");
	} else {
	ret = regulator_enable(st->vref);
	if (ret)
	return ret;
	ret = devm_add_action_or_reset(dev, ad7091r_remove, st);
	if (ret)
	return ret;
	}

	/* Use command mode by default to convert only desired channels*/
	ret = st->chip_info->set_mode(st, AD7091R_MODE_COMMAND);
	if (ret)
	return ret;

	return devm_iio_device_register(dev, iio_dev);
	}
	EXPORT_SYMBOL_NS_GPL(ad7091r_probe, "IIO_AD7091R");

	bool ad7091r_writeable_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case AD7091R_REG_RESULT:
	case AD7091R_REG_ALERT:
	return false;
	default:
	return true;
	}
	}
	EXPORT_SYMBOL_NS_GPL(ad7091r_writeable_reg, "IIO_AD7091R");

	bool ad7091r_volatile_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case AD7091R_REG_RESULT:
	case AD7091R_REG_ALERT:
	return true;
	default:
	return false;
	}
	}
	EXPORT_SYMBOL_NS_GPL(ad7091r_volatile_reg, "IIO_AD7091R");

	MODULE_AUTHOR("Beniamin Bia <beniamin.bia@analog.com>");
	MODULE_DESCRIPTION("Analog Devices AD7091Rx multi-channel converters");
	MODULE_LICENSE("GPL v2");