drivers/iio/dac/ad5761.c - linux/kernel/git/gregkh/char-misc - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * AD5721, AD5721R, AD5761, AD5761R, Voltage Output Digital to Analog Converter
  *
  * Copyright 2016 Qtechnology A/S
  * 2016 Ricardo Ribalda <ribalda@kernel.org>
  */
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/spi/spi.h>
 #include <linux/bitops.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/regulator/consumer.h>
 #include <linux/platform_data/ad5761.h>

 #define AD5761_ADDR(addr)		((addr & 0xf) << 16)
 #define AD5761_ADDR_NOOP		0x0
 #define AD5761_ADDR_DAC_WRITE		0x3
 #define AD5761_ADDR_CTRL_WRITE_REG	0x4
 #define AD5761_ADDR_SW_DATA_RESET	0x7
 #define AD5761_ADDR_DAC_READ		0xb
 #define AD5761_ADDR_CTRL_READ_REG	0xc
 #define AD5761_ADDR_SW_FULL_RESET	0xf

 #define AD5761_CTRL_USE_INTVREF		BIT(5)
 #define AD5761_CTRL_ETS			BIT(6)

 /**
  * struct ad5761_chip_info - chip specific information
  * @int_vref:	Value of the internal reference voltage in mV - 0 if external
  *		reference voltage is used
  * @channel:	channel specification
 */

 struct ad5761_chip_info {
 	unsigned long int_vref;
 	const struct iio_chan_spec channel;
 };

 struct ad5761_range_params {
 	int m;
 	int c;
 };

 enum ad5761_supported_device_ids {
 	ID_AD5721,
 	ID_AD5721R,
 	ID_AD5761,
 	ID_AD5761R,
 };

 /**
  * struct ad5761_state - driver instance specific data
  * @spi:		spi_device
  * @vref_reg:		reference voltage regulator
  * @use_intref:		true when the internal voltage reference is used
  * @vref:		actual voltage reference in mVolts
  * @range:		output range mode used
  * @lock:		lock to protect the data buffer during SPI ops
  * @data:		cache aligned spi buffer
  */
 struct ad5761_state {
 	struct spi_device		*spi;
 	struct regulator		*vref_reg;
 	struct mutex			lock;

 	bool use_intref;
 	int vref;
 	enum ad5761_voltage_range range;

 	/*
 	 * DMA (thus cache coherency maintenance) requires the
 	 * transfer buffers to live in their own cache lines.
 	 */
 	union {
 		__be32 d32;
 		u8 d8[4];
 	} data[3] ____cacheline_aligned;
 };

 static const struct ad5761_range_params ad5761_range_params[] = {
 	[AD5761_VOLTAGE_RANGE_M10V_10V] = {
 		.m = 80,
 		.c = 40,
 	},
 	[AD5761_VOLTAGE_RANGE_0V_10V] = {
 		.m = 40,
 		.c = 0,
 	},
 	[AD5761_VOLTAGE_RANGE_M5V_5V] = {
 		.m = 40,
 		.c = 20,
 	},
 	[AD5761_VOLTAGE_RANGE_0V_5V] = {
 		.m = 20,
 		.c = 0,
 	},
 	[AD5761_VOLTAGE_RANGE_M2V5_7V5] = {
 		.m = 40,
 		.c = 10,
 	},
 	[AD5761_VOLTAGE_RANGE_M3V_3V] = {
 		.m = 24,
 		.c = 12,
 	},
 	[AD5761_VOLTAGE_RANGE_0V_16V] = {
 		.m = 64,
 		.c = 0,
 	},
 	[AD5761_VOLTAGE_RANGE_0V_20V] = {
 		.m = 80,
 		.c = 0,
 	},
 };

 static int _ad5761_spi_write(struct ad5761_state *st, u8 addr, u16 val)
 {
 	st->data[0].d32 = cpu_to_be32(AD5761_ADDR(addr) | val);

 	return spi_write(st->spi, &st->data[0].d8[1], 3);
 }

 static int ad5761_spi_write(struct iio_dev *indio_dev, u8 addr, u16 val)
 {
 	struct ad5761_state *st = iio_priv(indio_dev);
 	int ret;

 	mutex_lock(&st->lock);
 	ret = _ad5761_spi_write(st, addr, val);
 	mutex_unlock(&st->lock);

 	return ret;
 }

 static int _ad5761_spi_read(struct ad5761_state *st, u8 addr, u16 *val)
 {
 	int ret;
 	struct spi_transfer xfers[] = {
 		{
 			.tx_buf = &st->data[0].d8[1],
 			.bits_per_word = 8,
 			.len = 3,
 			.cs_change = true,
 		}, {
 			.tx_buf = &st->data[1].d8[1],
 			.rx_buf = &st->data[2].d8[1],
 			.bits_per_word = 8,
 			.len = 3,
 		},
 	};

 	st->data[0].d32 = cpu_to_be32(AD5761_ADDR(addr));
 	st->data[1].d32 = cpu_to_be32(AD5761_ADDR(AD5761_ADDR_NOOP));

 	ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));

 	*val = be32_to_cpu(st->data[2].d32);

 	return ret;
 }

 static int ad5761_spi_read(struct iio_dev *indio_dev, u8 addr, u16 *val)
 {
 	struct ad5761_state *st = iio_priv(indio_dev);
 	int ret;

 	mutex_lock(&st->lock);
 	ret = _ad5761_spi_read(st, addr, val);
 	mutex_unlock(&st->lock);

 	return ret;
 }

 static int ad5761_spi_set_range(struct ad5761_state *st,
 				enum ad5761_voltage_range range)
 {
 	u16 aux;
 	int ret;

 	aux = (range & 0x7) | AD5761_CTRL_ETS;

 	if (st->use_intref)
 		aux |= AD5761_CTRL_USE_INTVREF;

 	ret = _ad5761_spi_write(st, AD5761_ADDR_SW_FULL_RESET, 0);
 	if (ret)
 		return ret;

 	ret = _ad5761_spi_write(st, AD5761_ADDR_CTRL_WRITE_REG, aux);
 	if (ret)
 		return ret;

 	st->range = range;

 	return 0;
 }

 static int ad5761_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val,
 			   int *val2,
 			   long mask)
 {
 	struct ad5761_state *st;
 	int ret;
 	u16 aux;

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		ret = ad5761_spi_read(indio_dev, AD5761_ADDR_DAC_READ, &aux);
 		if (ret)
 			return ret;
 		*val = aux >> chan->scan_type.shift;
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		st = iio_priv(indio_dev);
 		*val = st->vref * ad5761_range_params[st->range].m;
 		*val /= 10;
 		*val2 = chan->scan_type.realbits;
 		return IIO_VAL_FRACTIONAL_LOG2;
 	case IIO_CHAN_INFO_OFFSET:
 		st = iio_priv(indio_dev);
 		*val = -(1 << chan->scan_type.realbits);
 		*val *=	ad5761_range_params[st->range].c;
 		*val /=	ad5761_range_params[st->range].m;
 		return IIO_VAL_INT;
 	default:
 		return -EINVAL;
 	}
 }

 static int ad5761_write_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int val,
 			    int val2,
 			    long mask)
 {
 	u16 aux;

 	if (mask != IIO_CHAN_INFO_RAW)
 		return -EINVAL;

 	if (val2 || (val << chan->scan_type.shift) > 0xffff || val < 0)
 		return -EINVAL;

 	aux = val << chan->scan_type.shift;

 	return ad5761_spi_write(indio_dev, AD5761_ADDR_DAC_WRITE, aux);
 }

 static const struct iio_info ad5761_info = {
 	.read_raw = &ad5761_read_raw,
 	.write_raw = &ad5761_write_raw,
 };

 #define AD5761_CHAN(_bits) {				\
 	.type = IIO_VOLTAGE,				\
 	.output = 1,					\
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
 		BIT(IIO_CHAN_INFO_OFFSET),		\
 	.scan_type = {					\
 		.sign = 'u',				\
 		.realbits = (_bits),			\
 		.storagebits = 16,			\
 		.shift = 16 - (_bits),			\
 	},						\
 }

 static const struct ad5761_chip_info ad5761_chip_infos[] = {
 	[ID_AD5721] = {
 		.int_vref = 0,
 		.channel = AD5761_CHAN(12),
 	},
 	[ID_AD5721R] = {
 		.int_vref = 2500,
 		.channel = AD5761_CHAN(12),
 	},
 	[ID_AD5761] = {
 		.int_vref = 0,
 		.channel = AD5761_CHAN(16),
 	},
 	[ID_AD5761R] = {
 		.int_vref = 2500,
 		.channel = AD5761_CHAN(16),
 	},
 };

 static int ad5761_get_vref(struct ad5761_state *st,
 			   const struct ad5761_chip_info *chip_info)
 {
 	int ret;

 	st->vref_reg = devm_regulator_get_optional(&st->spi->dev, "vref");
 	if (PTR_ERR(st->vref_reg) == -ENODEV) {
 		/* Use Internal regulator */
 		if (!chip_info->int_vref) {
 			dev_err(&st->spi->dev,
 				"Voltage reference not found\n");
 			return -EIO;
 		}

 		st->use_intref = true;
 		st->vref = chip_info->int_vref;
 		return 0;
 	}

 	if (IS_ERR(st->vref_reg)) {
 		dev_err(&st->spi->dev,
 			"Error getting voltage reference regulator\n");
 		return PTR_ERR(st->vref_reg);
 	}

 	ret = regulator_enable(st->vref_reg);
 	if (ret) {
 		dev_err(&st->spi->dev,
 			 "Failed to enable voltage reference\n");
 		return ret;
 	}

 	ret = regulator_get_voltage(st->vref_reg);
 	if (ret < 0) {
 		dev_err(&st->spi->dev,
 			 "Failed to get voltage reference value\n");
 		goto disable_regulator_vref;
 	}

 	if (ret < 2000000 || ret > 3000000) {
 		dev_warn(&st->spi->dev,
 			 "Invalid external voltage ref. value %d uV\n", ret);
 		ret = -EIO;
 		goto disable_regulator_vref;
 	}

 	st->vref = ret / 1000;
 	st->use_intref = false;

 	return 0;

 disable_regulator_vref:
 	regulator_disable(st->vref_reg);
 	st->vref_reg = NULL;
 	return ret;
 }

 static int ad5761_probe(struct spi_device *spi)
 {
 	struct iio_dev *iio_dev;
 	struct ad5761_state *st;
 	int ret;
 	const struct ad5761_chip_info *chip_info =
 		&ad5761_chip_infos[spi_get_device_id(spi)->driver_data];
 	enum ad5761_voltage_range voltage_range = AD5761_VOLTAGE_RANGE_0V_5V;
 	struct ad5761_platform_data *pdata = dev_get_platdata(&spi->dev);

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

 	st = iio_priv(iio_dev);

 	st->spi = spi;
 	spi_set_drvdata(spi, iio_dev);

 	ret = ad5761_get_vref(st, chip_info);
 	if (ret)
 		return ret;

 	if (pdata)
 		voltage_range = pdata->voltage_range;

 	mutex_init(&st->lock);

 	ret = ad5761_spi_set_range(st, voltage_range);
 	if (ret)
 		goto disable_regulator_err;

 	iio_dev->info = &ad5761_info;
 	iio_dev->modes = INDIO_DIRECT_MODE;
 	iio_dev->channels = &chip_info->channel;
 	iio_dev->num_channels = 1;
 	iio_dev->name = spi_get_device_id(st->spi)->name;
 	ret = iio_device_register(iio_dev);
 	if (ret)
 		goto disable_regulator_err;

 	return 0;

 disable_regulator_err:
 	if (!IS_ERR_OR_NULL(st->vref_reg))
 		regulator_disable(st->vref_reg);

 	return ret;
 }

 static int ad5761_remove(struct spi_device *spi)
 {
 	struct iio_dev *iio_dev = spi_get_drvdata(spi);
 	struct ad5761_state *st = iio_priv(iio_dev);

 	iio_device_unregister(iio_dev);

 	if (!IS_ERR_OR_NULL(st->vref_reg))
 		regulator_disable(st->vref_reg);

 	return 0;
 }

 static const struct spi_device_id ad5761_id[] = {
 	{"ad5721", ID_AD5721},
 	{"ad5721r", ID_AD5721R},
 	{"ad5761", ID_AD5761},
 	{"ad5761r", ID_AD5761R},
 	{}
 };
 MODULE_DEVICE_TABLE(spi, ad5761_id);

 static struct spi_driver ad5761_driver = {
 	.driver = {
 		   .name = "ad5761",
 		   },
 	.probe = ad5761_probe,
 	.remove = ad5761_remove,
 	.id_table = ad5761_id,
 };
 module_spi_driver(ad5761_driver);

 MODULE_AUTHOR("Ricardo Ribalda <ribalda@kernel.org>");
 MODULE_DESCRIPTION("Analog Devices AD5721, AD5721R, AD5761, AD5761R driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* AD5721, AD5721R, AD5761, AD5761R, Voltage Output Digital to Analog Converter
	*
	* Copyright 2016 Qtechnology A/S
	* 2016 Ricardo Ribalda <ribalda@kernel.org>
	*/
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/spi/spi.h>
	#include <linux/bitops.h>
	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/regulator/consumer.h>
	#include <linux/platform_data/ad5761.h>

	#define AD5761_ADDR(addr) ((addr & 0xf) << 16)
	#define AD5761_ADDR_NOOP 0x0
	#define AD5761_ADDR_DAC_WRITE 0x3
	#define AD5761_ADDR_CTRL_WRITE_REG 0x4
	#define AD5761_ADDR_SW_DATA_RESET 0x7
	#define AD5761_ADDR_DAC_READ 0xb
	#define AD5761_ADDR_CTRL_READ_REG 0xc
	#define AD5761_ADDR_SW_FULL_RESET 0xf

	#define AD5761_CTRL_USE_INTVREF BIT(5)
	#define AD5761_CTRL_ETS BIT(6)

	/**
	* struct ad5761_chip_info - chip specific information
	* @int_vref: Value of the internal reference voltage in mV - 0 if external
	* reference voltage is used
	* @channel: channel specification
	*/

	struct ad5761_chip_info {
	unsigned long int_vref;
	const struct iio_chan_spec channel;
	};

	struct ad5761_range_params {
	int m;
	int c;
	};

	enum ad5761_supported_device_ids {
	ID_AD5721,
	ID_AD5721R,
	ID_AD5761,
	ID_AD5761R,
	};

	/**
	* struct ad5761_state - driver instance specific data
	* @spi: spi_device
	* @vref_reg: reference voltage regulator
	* @use_intref: true when the internal voltage reference is used
	* @vref: actual voltage reference in mVolts
	* @range: output range mode used
	* @lock: lock to protect the data buffer during SPI ops
	* @data: cache aligned spi buffer
	*/
	struct ad5761_state {
	struct spi_device *spi;
	struct regulator *vref_reg;
	struct mutex lock;

	bool use_intref;
	int vref;
	enum ad5761_voltage_range range;

	/*
	* DMA (thus cache coherency maintenance) requires the
	* transfer buffers to live in their own cache lines.
	*/
	union {
	__be32 d32;
	u8 d8[4];
	} data[3] ____cacheline_aligned;
	};

	static const struct ad5761_range_params ad5761_range_params[] = {
	[AD5761_VOLTAGE_RANGE_M10V_10V] = {
	.m = 80,
	.c = 40,
	},
	[AD5761_VOLTAGE_RANGE_0V_10V] = {
	.m = 40,
	.c = 0,
	},
	[AD5761_VOLTAGE_RANGE_M5V_5V] = {
	.m = 40,
	.c = 20,
	},
	[AD5761_VOLTAGE_RANGE_0V_5V] = {
	.m = 20,
	.c = 0,
	},
	[AD5761_VOLTAGE_RANGE_M2V5_7V5] = {
	.m = 40,
	.c = 10,
	},
	[AD5761_VOLTAGE_RANGE_M3V_3V] = {
	.m = 24,
	.c = 12,
	},
	[AD5761_VOLTAGE_RANGE_0V_16V] = {
	.m = 64,
	.c = 0,
	},
	[AD5761_VOLTAGE_RANGE_0V_20V] = {
	.m = 80,
	.c = 0,
	},
	};

	static int _ad5761_spi_write(struct ad5761_state *st, u8 addr, u16 val)
	{
	st->data[0].d32 = cpu_to_be32(AD5761_ADDR(addr) \| val);

	return spi_write(st->spi, &st->data[0].d8[1], 3);
	}

	static int ad5761_spi_write(struct iio_dev *indio_dev, u8 addr, u16 val)
	{
	struct ad5761_state *st = iio_priv(indio_dev);
	int ret;

	mutex_lock(&st->lock);
	ret = _ad5761_spi_write(st, addr, val);
	mutex_unlock(&st->lock);

	return ret;
	}

	static int _ad5761_spi_read(struct ad5761_state st, u8 addr, u16 val)
	{
	int ret;
	struct spi_transfer xfers[] = {
	{
	.tx_buf = &st->data[0].d8[1],
	.bits_per_word = 8,
	.len = 3,
	.cs_change = true,
	}, {
	.tx_buf = &st->data[1].d8[1],
	.rx_buf = &st->data[2].d8[1],
	.bits_per_word = 8,
	.len = 3,
	},
	};

	st->data[0].d32 = cpu_to_be32(AD5761_ADDR(addr));
	st->data[1].d32 = cpu_to_be32(AD5761_ADDR(AD5761_ADDR_NOOP));

	ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));

	*val = be32_to_cpu(st->data[2].d32);

	return ret;
	}

	static int ad5761_spi_read(struct iio_dev indio_dev, u8 addr, u16 val)
	{
	struct ad5761_state *st = iio_priv(indio_dev);
	int ret;

	mutex_lock(&st->lock);
	ret = _ad5761_spi_read(st, addr, val);
	mutex_unlock(&st->lock);

	return ret;
	}

	static int ad5761_spi_set_range(struct ad5761_state *st,
	enum ad5761_voltage_range range)
	{
	u16 aux;
	int ret;

	aux = (range & 0x7) \| AD5761_CTRL_ETS;

	if (st->use_intref)
	aux \|= AD5761_CTRL_USE_INTVREF;

	ret = _ad5761_spi_write(st, AD5761_ADDR_SW_FULL_RESET, 0);
	if (ret)
	return ret;

	ret = _ad5761_spi_write(st, AD5761_ADDR_CTRL_WRITE_REG, aux);
	if (ret)
	return ret;

	st->range = range;

	return 0;
	}

	static int ad5761_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int *val,
	int *val2,
	long mask)
	{
	struct ad5761_state *st;
	int ret;
	u16 aux;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	ret = ad5761_spi_read(indio_dev, AD5761_ADDR_DAC_READ, &aux);
	if (ret)
	return ret;
	*val = aux >> chan->scan_type.shift;
	return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
	st = iio_priv(indio_dev);
	val = st->vref ad5761_range_params[st->range].m;
	*val /= 10;
	*val2 = chan->scan_type.realbits;
	return IIO_VAL_FRACTIONAL_LOG2;
	case IIO_CHAN_INFO_OFFSET:
	st = iio_priv(indio_dev);
	*val = -(1 << chan->scan_type.realbits);
	val = ad5761_range_params[st->range].c;
	*val /= ad5761_range_params[st->range].m;
	return IIO_VAL_INT;
	default:
	return -EINVAL;
	}
	}

	static int ad5761_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val,
	int val2,
	long mask)
	{
	u16 aux;

	if (mask != IIO_CHAN_INFO_RAW)
	return -EINVAL;

	if (val2 \|\| (val << chan->scan_type.shift) > 0xffff \|\| val < 0)
	return -EINVAL;

	aux = val << chan->scan_type.shift;

	return ad5761_spi_write(indio_dev, AD5761_ADDR_DAC_WRITE, aux);
	}

	static const struct iio_info ad5761_info = {
	.read_raw = &ad5761_read_raw,
	.write_raw = &ad5761_write_raw,
	};

	#define AD5761_CHAN(_bits) { \
	.type = IIO_VOLTAGE, \
	.output = 1, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \| \
	BIT(IIO_CHAN_INFO_OFFSET), \
	.scan_type = { \
	.sign = 'u', \
	.realbits = (_bits), \
	.storagebits = 16, \
	.shift = 16 - (_bits), \
	}, \
	}

	static const struct ad5761_chip_info ad5761_chip_infos[] = {
	[ID_AD5721] = {
	.int_vref = 0,
	.channel = AD5761_CHAN(12),
	},
	[ID_AD5721R] = {
	.int_vref = 2500,
	.channel = AD5761_CHAN(12),
	},
	[ID_AD5761] = {
	.int_vref = 0,
	.channel = AD5761_CHAN(16),
	},
	[ID_AD5761R] = {
	.int_vref = 2500,
	.channel = AD5761_CHAN(16),
	},
	};

	static int ad5761_get_vref(struct ad5761_state *st,
	const struct ad5761_chip_info *chip_info)
	{
	int ret;

	st->vref_reg = devm_regulator_get_optional(&st->spi->dev, "vref");
	if (PTR_ERR(st->vref_reg) == -ENODEV) {
	/* Use Internal regulator */
	if (!chip_info->int_vref) {
	dev_err(&st->spi->dev,
	"Voltage reference not found\n");
	return -EIO;
	}

	st->use_intref = true;
	st->vref = chip_info->int_vref;
	return 0;
	}

	if (IS_ERR(st->vref_reg)) {
	dev_err(&st->spi->dev,
	"Error getting voltage reference regulator\n");
	return PTR_ERR(st->vref_reg);
	}

	ret = regulator_enable(st->vref_reg);
	if (ret) {
	dev_err(&st->spi->dev,
	"Failed to enable voltage reference\n");
	return ret;
	}

	ret = regulator_get_voltage(st->vref_reg);
	if (ret < 0) {
	dev_err(&st->spi->dev,
	"Failed to get voltage reference value\n");
	goto disable_regulator_vref;
	}

	if (ret < 2000000 \|\| ret > 3000000) {
	dev_warn(&st->spi->dev,
	"Invalid external voltage ref. value %d uV\n", ret);
	ret = -EIO;
	goto disable_regulator_vref;
	}

	st->vref = ret / 1000;
	st->use_intref = false;

	return 0;

	disable_regulator_vref:
	regulator_disable(st->vref_reg);
	st->vref_reg = NULL;
	return ret;
	}

	static int ad5761_probe(struct spi_device *spi)
	{
	struct iio_dev *iio_dev;
	struct ad5761_state *st;
	int ret;
	const struct ad5761_chip_info *chip_info =
	&ad5761_chip_infos[spi_get_device_id(spi)->driver_data];
	enum ad5761_voltage_range voltage_range = AD5761_VOLTAGE_RANGE_0V_5V;
	struct ad5761_platform_data *pdata = dev_get_platdata(&spi->dev);

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

	st = iio_priv(iio_dev);

	st->spi = spi;
	spi_set_drvdata(spi, iio_dev);

	ret = ad5761_get_vref(st, chip_info);
	if (ret)
	return ret;

	if (pdata)
	voltage_range = pdata->voltage_range;

	mutex_init(&st->lock);

	ret = ad5761_spi_set_range(st, voltage_range);
	if (ret)
	goto disable_regulator_err;

	iio_dev->info = &ad5761_info;
	iio_dev->modes = INDIO_DIRECT_MODE;
	iio_dev->channels = &chip_info->channel;
	iio_dev->num_channels = 1;
	iio_dev->name = spi_get_device_id(st->spi)->name;
	ret = iio_device_register(iio_dev);
	if (ret)
	goto disable_regulator_err;

	return 0;

	disable_regulator_err:
	if (!IS_ERR_OR_NULL(st->vref_reg))
	regulator_disable(st->vref_reg);

	return ret;
	}

	static int ad5761_remove(struct spi_device *spi)
	{
	struct iio_dev *iio_dev = spi_get_drvdata(spi);
	struct ad5761_state *st = iio_priv(iio_dev);

	iio_device_unregister(iio_dev);

	if (!IS_ERR_OR_NULL(st->vref_reg))
	regulator_disable(st->vref_reg);

	return 0;
	}

	static const struct spi_device_id ad5761_id[] = {
	{"ad5721", ID_AD5721},
	{"ad5721r", ID_AD5721R},
	{"ad5761", ID_AD5761},
	{"ad5761r", ID_AD5761R},
	{}
	};
	MODULE_DEVICE_TABLE(spi, ad5761_id);

	static struct spi_driver ad5761_driver = {
	.driver = {
	.name = "ad5761",
	},
	.probe = ad5761_probe,
	.remove = ad5761_remove,
	.id_table = ad5761_id,
	};
	module_spi_driver(ad5761_driver);

	MODULE_AUTHOR("Ricardo Ribalda <ribalda@kernel.org>");
	MODULE_DESCRIPTION("Analog Devices AD5721, AD5721R, AD5761, AD5761R driver");
	MODULE_LICENSE("GPL v2");