drivers/staging/iio/dac/ad5446.c - kernel/windcharger - Git at Google

 /*
  * AD5446 SPI DAC driver
  *
  * Copyright 2010 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */

 #include <linux/interrupt.h>
 #include <linux/workqueue.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/list.h>
 #include <linux/spi/spi.h>
 #include <linux/regulator/consumer.h>
 #include <linux/err.h>
 #include <linux/module.h>

 #include "../iio.h"
 #include "../sysfs.h"
 #include "dac.h"

 #include "ad5446.h"

 static void ad5446_store_sample(struct ad5446_state *st, unsigned val)
 {
 	st->data.d16 = cpu_to_be16(AD5446_LOAD | val);
 }

 static void ad5542_store_sample(struct ad5446_state *st, unsigned val)
 {
 	st->data.d16 = cpu_to_be16(val);
 }

 static void ad5620_store_sample(struct ad5446_state *st, unsigned val)
 {
 	st->data.d16 = cpu_to_be16(AD5620_LOAD | val);
 }

 static void ad5660_store_sample(struct ad5446_state *st, unsigned val)
 {
 	val |= AD5660_LOAD;
 	st->data.d24[0] = (val >> 16) & 0xFF;
 	st->data.d24[1] = (val >> 8) & 0xFF;
 	st->data.d24[2] = val & 0xFF;
 }

 static void ad5620_store_pwr_down(struct ad5446_state *st, unsigned mode)
 {
 	st->data.d16 = cpu_to_be16(mode << 14);
 }

 static void ad5660_store_pwr_down(struct ad5446_state *st, unsigned mode)
 {
 	unsigned val = mode << 16;

 	st->data.d24[0] = (val >> 16) & 0xFF;
 	st->data.d24[1] = (val >> 8) & 0xFF;
 	st->data.d24[2] = val & 0xFF;
 }

 static ssize_t ad5446_write_powerdown_mode(struct device *dev,
 				       struct device_attribute *attr,
 				       const char *buf, size_t len)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5446_state *st = iio_priv(indio_dev);

 	if (sysfs_streq(buf, "1kohm_to_gnd"))
 		st->pwr_down_mode = MODE_PWRDWN_1k;
 	else if (sysfs_streq(buf, "100kohm_to_gnd"))
 		st->pwr_down_mode = MODE_PWRDWN_100k;
 	else if (sysfs_streq(buf, "three_state"))
 		st->pwr_down_mode = MODE_PWRDWN_TRISTATE;
 	else
 		return -EINVAL;

 	return len;
 }

 static ssize_t ad5446_read_powerdown_mode(struct device *dev,
 				      struct device_attribute *attr, char *buf)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5446_state *st = iio_priv(indio_dev);

 	char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"};

 	return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
 }

 static ssize_t ad5446_read_dac_powerdown(struct device *dev,
 					   struct device_attribute *attr,
 					   char *buf)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5446_state *st = iio_priv(indio_dev);

 	return sprintf(buf, "%d\n", st->pwr_down);
 }

 static ssize_t ad5446_write_dac_powerdown(struct device *dev,
 					    struct device_attribute *attr,
 					    const char *buf, size_t len)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5446_state *st = iio_priv(indio_dev);
 	unsigned long readin;
 	int ret;

 	ret = strict_strtol(buf, 10, &readin);
 	if (ret)
 		return ret;

 	if (readin > 1)
 		ret = -EINVAL;

 	mutex_lock(&indio_dev->mlock);
 	st->pwr_down = readin;

 	if (st->pwr_down)
 		st->chip_info->store_pwr_down(st, st->pwr_down_mode);
 	else
 		st->chip_info->store_sample(st, st->cached_val);

 	ret = spi_sync(st->spi, &st->msg);
 	mutex_unlock(&indio_dev->mlock);

 	return ret ? ret : len;
 }

 static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO | S_IWUSR,
 			ad5446_read_powerdown_mode,
 			ad5446_write_powerdown_mode, 0);

 static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
 			"1kohm_to_gnd 100kohm_to_gnd three_state");

 static IIO_DEVICE_ATTR(out_voltage0_powerdown, S_IRUGO | S_IWUSR,
 			ad5446_read_dac_powerdown,
 			ad5446_write_dac_powerdown, 0);

 static struct attribute *ad5446_attributes[] = {
 	&iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
 	&iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
 	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
 	NULL,
 };

 static umode_t ad5446_attr_is_visible(struct kobject *kobj,
 				     struct attribute *attr, int n)
 {
 	struct device *dev = container_of(kobj, struct device, kobj);
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct ad5446_state *st = iio_priv(indio_dev);

 	umode_t mode = attr->mode;

 	if (!st->chip_info->store_pwr_down &&
 		(attr == &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr ||
 		attr == &iio_dev_attr_out_voltage_powerdown_mode.
 		 dev_attr.attr ||
 		attr ==
 		&iio_const_attr_out_voltage_powerdown_mode_available.
 		 dev_attr.attr))
 		mode = 0;

 	return mode;
 }

 static const struct attribute_group ad5446_attribute_group = {
 	.attrs = ad5446_attributes,
 	.is_visible = ad5446_attr_is_visible,
 };

 #define AD5446_CHANNEL(bits, storage, shift) { \
 	.type = IIO_VOLTAGE, \
 	.indexed = 1, \
 	.output = 1, \
 	.channel = 0, \
 	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT, \
 	.scan_type = IIO_ST('u', (bits), (storage), (shift)) \
 }

 static const struct ad5446_chip_info ad5446_chip_info_tbl[] = {
 	[ID_AD5444] = {
 		.channel = AD5446_CHANNEL(12, 16, 2),
 		.store_sample = ad5446_store_sample,
 	},
 	[ID_AD5446] = {
 		.channel = AD5446_CHANNEL(14, 16, 0),
 		.store_sample = ad5446_store_sample,
 	},
 	[ID_AD5541A] = {
 		.channel = AD5446_CHANNEL(16, 16, 0),
 		.store_sample = ad5542_store_sample,
 	},
 	[ID_AD5542A] = {
 		.channel = AD5446_CHANNEL(16, 16, 0),
 		.store_sample = ad5542_store_sample,
 	},
 	[ID_AD5543] = {
 		.channel = AD5446_CHANNEL(16, 16, 0),
 		.store_sample = ad5542_store_sample,
 	},
 	[ID_AD5512A] = {
 		.channel = AD5446_CHANNEL(12, 16, 4),
 		.store_sample = ad5542_store_sample,
 	},
 	[ID_AD5553] = {
 		.channel = AD5446_CHANNEL(14, 16, 0),
 		.store_sample = ad5542_store_sample,
 	},
 	[ID_AD5601] = {
 		.channel = AD5446_CHANNEL(8, 16, 6),
 		.store_sample = ad5542_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5611] = {
 		.channel = AD5446_CHANNEL(10, 16, 4),
 		.store_sample = ad5542_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5621] = {
 		.channel = AD5446_CHANNEL(12, 16, 2),
 		.store_sample = ad5542_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5620_2500] = {
 		.channel = AD5446_CHANNEL(12, 16, 2),
 		.int_vref_mv = 2500,
 		.store_sample = ad5620_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5620_1250] = {
 		.channel = AD5446_CHANNEL(12, 16, 2),
 		.int_vref_mv = 1250,
 		.store_sample = ad5620_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5640_2500] = {
 		.channel = AD5446_CHANNEL(14, 16, 0),
 		.int_vref_mv = 2500,
 		.store_sample = ad5620_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5640_1250] = {
 		.channel = AD5446_CHANNEL(14, 16, 0),
 		.int_vref_mv = 1250,
 		.store_sample = ad5620_store_sample,
 		.store_pwr_down = ad5620_store_pwr_down,
 	},
 	[ID_AD5660_2500] = {
 		.channel = AD5446_CHANNEL(16, 16, 0),
 		.int_vref_mv = 2500,
 		.store_sample = ad5660_store_sample,
 		.store_pwr_down = ad5660_store_pwr_down,
 	},
 	[ID_AD5660_1250] = {
 		.channel = AD5446_CHANNEL(16, 16, 0),
 		.int_vref_mv = 1250,
 		.store_sample = ad5660_store_sample,
 		.store_pwr_down = ad5660_store_pwr_down,
 	},
 };

 static int ad5446_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val,
 			   int *val2,
 			   long m)
 {
 	struct ad5446_state *st = iio_priv(indio_dev);
 	unsigned long scale_uv;

 	switch (m) {
 	case IIO_CHAN_INFO_SCALE:
 		scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
 		*val =  scale_uv / 1000;
 		*val2 = (scale_uv % 1000) * 1000;
 		return IIO_VAL_INT_PLUS_MICRO;

 	}
 	return -EINVAL;
 }

 static int ad5446_write_raw(struct iio_dev *indio_dev,
 			       struct iio_chan_spec const *chan,
 			       int val,
 			       int val2,
 			       long mask)
 {
 	struct ad5446_state *st = iio_priv(indio_dev);
 	int ret;

 	switch (mask) {
 	case 0:
 		if (val >= (1 << chan->scan_type.realbits) || val < 0)
 			return -EINVAL;

 		val <<= chan->scan_type.shift;
 		mutex_lock(&indio_dev->mlock);
 		st->cached_val = val;
 		st->chip_info->store_sample(st, val);
 		ret = spi_sync(st->spi, &st->msg);
 		mutex_unlock(&indio_dev->mlock);
 		break;
 	default:
 		ret = -EINVAL;
 	}

 	return ret;
 }

 static const struct iio_info ad5446_info = {
 	.read_raw = ad5446_read_raw,
 	.write_raw = ad5446_write_raw,
 	.attrs = &ad5446_attribute_group,
 	.driver_module = THIS_MODULE,
 };

 static int __devinit ad5446_probe(struct spi_device *spi)
 {
 	struct ad5446_state *st;
 	struct iio_dev *indio_dev;
 	struct regulator *reg;
 	int ret, voltage_uv = 0;

 	reg = regulator_get(&spi->dev, "vcc");
 	if (!IS_ERR(reg)) {
 		ret = regulator_enable(reg);
 		if (ret)
 			goto error_put_reg;

 		voltage_uv = regulator_get_voltage(reg);
 	}

 	indio_dev = iio_allocate_device(sizeof(*st));
 	if (indio_dev == NULL) {
 		ret = -ENOMEM;
 		goto error_disable_reg;
 	}
 	st = iio_priv(indio_dev);
 	st->chip_info =
 		&ad5446_chip_info_tbl[spi_get_device_id(spi)->driver_data];

 	spi_set_drvdata(spi, indio_dev);
 	st->reg = reg;
 	st->spi = spi;

 	/* Estabilish that the iio_dev is a child of the spi device */
 	indio_dev->dev.parent = &spi->dev;
 	indio_dev->name = spi_get_device_id(spi)->name;
 	indio_dev->info = &ad5446_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = &st->chip_info->channel;
 	indio_dev->num_channels = 1;

 	/* Setup default message */

 	st->xfer.tx_buf = &st->data;
 	st->xfer.len = st->chip_info->channel.scan_type.storagebits / 8;

 	spi_message_init(&st->msg);
 	spi_message_add_tail(&st->xfer, &st->msg);

 	switch (spi_get_device_id(spi)->driver_data) {
 	case ID_AD5620_2500:
 	case ID_AD5620_1250:
 	case ID_AD5640_2500:
 	case ID_AD5640_1250:
 	case ID_AD5660_2500:
 	case ID_AD5660_1250:
 		st->vref_mv = st->chip_info->int_vref_mv;
 		break;
 	default:
 		if (voltage_uv)
 			st->vref_mv = voltage_uv / 1000;
 		else
 			dev_warn(&spi->dev,
 				 "reference voltage unspecified\n");
 	}

 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto error_free_device;

 	return 0;

 error_free_device:
 	iio_free_device(indio_dev);
 error_disable_reg:
 	if (!IS_ERR(reg))
 		regulator_disable(reg);
 error_put_reg:
 	if (!IS_ERR(reg))
 		regulator_put(reg);

 	return ret;
 }

 static int ad5446_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
 	struct ad5446_state *st = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);
 	if (!IS_ERR(st->reg)) {
 		regulator_disable(st->reg);
 		regulator_put(st->reg);
 	}
 	iio_free_device(indio_dev);

 	return 0;
 }

 static const struct spi_device_id ad5446_id[] = {
 	{"ad5444", ID_AD5444},
 	{"ad5446", ID_AD5446},
 	{"ad5512a", ID_AD5512A},
 	{"ad5541a", ID_AD5541A},
 	{"ad5542a", ID_AD5542A},
 	{"ad5543", ID_AD5543},
 	{"ad5553", ID_AD5553},
 	{"ad5601", ID_AD5601},
 	{"ad5611", ID_AD5611},
 	{"ad5621", ID_AD5621},
 	{"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 	{"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 	{"ad5640-2500", ID_AD5640_2500},
 	{"ad5640-1250", ID_AD5640_1250},
 	{"ad5660-2500", ID_AD5660_2500},
 	{"ad5660-1250", ID_AD5660_1250},
 	{}
 };
 MODULE_DEVICE_TABLE(spi, ad5446_id);

 static struct spi_driver ad5446_driver = {
 	.driver = {
 		.name	= "ad5446",
 		.owner	= THIS_MODULE,
 	},
 	.probe		= ad5446_probe,
 	.remove		= __devexit_p(ad5446_remove),
 	.id_table	= ad5446_id,
 };
 module_spi_driver(ad5446_driver);

 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 MODULE_LICENSE("GPL v2");
	/*
	* AD5446 SPI DAC driver
	*
	* Copyright 2010 Analog Devices Inc.
	*
	* Licensed under the GPL-2 or later.
	*/

	#include <linux/interrupt.h>
	#include <linux/workqueue.h>
	#include <linux/device.h>
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/sysfs.h>
	#include <linux/list.h>
	#include <linux/spi/spi.h>
	#include <linux/regulator/consumer.h>
	#include <linux/err.h>
	#include <linux/module.h>

	#include "../iio.h"
	#include "../sysfs.h"
	#include "dac.h"

	#include "ad5446.h"

	static void ad5446_store_sample(struct ad5446_state *st, unsigned val)
	{
	st->data.d16 = cpu_to_be16(AD5446_LOAD \| val);
	}

	static void ad5542_store_sample(struct ad5446_state *st, unsigned val)
	{
	st->data.d16 = cpu_to_be16(val);
	}

	static void ad5620_store_sample(struct ad5446_state *st, unsigned val)
	{
	st->data.d16 = cpu_to_be16(AD5620_LOAD \| val);
	}

	static void ad5660_store_sample(struct ad5446_state *st, unsigned val)
	{
	val \|= AD5660_LOAD;
	st->data.d24[0] = (val >> 16) & 0xFF;
	st->data.d24[1] = (val >> 8) & 0xFF;
	st->data.d24[2] = val & 0xFF;
	}

	static void ad5620_store_pwr_down(struct ad5446_state *st, unsigned mode)
	{
	st->data.d16 = cpu_to_be16(mode << 14);
	}

	static void ad5660_store_pwr_down(struct ad5446_state *st, unsigned mode)
	{
	unsigned val = mode << 16;

	st->data.d24[0] = (val >> 16) & 0xFF;
	st->data.d24[1] = (val >> 8) & 0xFF;
	st->data.d24[2] = val & 0xFF;
	}

	static ssize_t ad5446_write_powerdown_mode(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t len)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5446_state *st = iio_priv(indio_dev);

	if (sysfs_streq(buf, "1kohm_to_gnd"))
	st->pwr_down_mode = MODE_PWRDWN_1k;
	else if (sysfs_streq(buf, "100kohm_to_gnd"))
	st->pwr_down_mode = MODE_PWRDWN_100k;
	else if (sysfs_streq(buf, "three_state"))
	st->pwr_down_mode = MODE_PWRDWN_TRISTATE;
	else
	return -EINVAL;

	return len;
	}

	static ssize_t ad5446_read_powerdown_mode(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5446_state *st = iio_priv(indio_dev);

	char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"};

	return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
	}

	static ssize_t ad5446_read_dac_powerdown(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5446_state *st = iio_priv(indio_dev);

	return sprintf(buf, "%d\n", st->pwr_down);
	}

	static ssize_t ad5446_write_dac_powerdown(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t len)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5446_state *st = iio_priv(indio_dev);
	unsigned long readin;
	int ret;

	ret = strict_strtol(buf, 10, &readin);
	if (ret)
	return ret;

	if (readin > 1)
	ret = -EINVAL;

	mutex_lock(&indio_dev->mlock);
	st->pwr_down = readin;

	if (st->pwr_down)
	st->chip_info->store_pwr_down(st, st->pwr_down_mode);
	else
	st->chip_info->store_sample(st, st->cached_val);

	ret = spi_sync(st->spi, &st->msg);
	mutex_unlock(&indio_dev->mlock);

	return ret ? ret : len;
	}

	static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO \| S_IWUSR,
	ad5446_read_powerdown_mode,
	ad5446_write_powerdown_mode, 0);

	static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
	"1kohm_to_gnd 100kohm_to_gnd three_state");

	static IIO_DEVICE_ATTR(out_voltage0_powerdown, S_IRUGO \| S_IWUSR,
	ad5446_read_dac_powerdown,
	ad5446_write_dac_powerdown, 0);

	static struct attribute *ad5446_attributes[] = {
	&iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
	&iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
	NULL,
	};

	static umode_t ad5446_attr_is_visible(struct kobject *kobj,
	struct attribute *attr, int n)
	{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5446_state *st = iio_priv(indio_dev);

	umode_t mode = attr->mode;

	if (!st->chip_info->store_pwr_down &&
	(attr == &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr \|\|
	attr == &iio_dev_attr_out_voltage_powerdown_mode.
	dev_attr.attr \|\|
	attr ==
	&iio_const_attr_out_voltage_powerdown_mode_available.
	dev_attr.attr))
	mode = 0;

	return mode;
	}

	static const struct attribute_group ad5446_attribute_group = {
	.attrs = ad5446_attributes,
	.is_visible = ad5446_attr_is_visible,
	};

	#define AD5446_CHANNEL(bits, storage, shift) { \
	.type = IIO_VOLTAGE, \
	.indexed = 1, \
	.output = 1, \
	.channel = 0, \
	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT, \
	.scan_type = IIO_ST('u', (bits), (storage), (shift)) \
	}

	static const struct ad5446_chip_info ad5446_chip_info_tbl[] = {
	[ID_AD5444] = {
	.channel = AD5446_CHANNEL(12, 16, 2),
	.store_sample = ad5446_store_sample,
	},
	[ID_AD5446] = {
	.channel = AD5446_CHANNEL(14, 16, 0),
	.store_sample = ad5446_store_sample,
	},
	[ID_AD5541A] = {
	.channel = AD5446_CHANNEL(16, 16, 0),
	.store_sample = ad5542_store_sample,
	},
	[ID_AD5542A] = {
	.channel = AD5446_CHANNEL(16, 16, 0),
	.store_sample = ad5542_store_sample,
	},
	[ID_AD5543] = {
	.channel = AD5446_CHANNEL(16, 16, 0),
	.store_sample = ad5542_store_sample,
	},
	[ID_AD5512A] = {
	.channel = AD5446_CHANNEL(12, 16, 4),
	.store_sample = ad5542_store_sample,
	},
	[ID_AD5553] = {
	.channel = AD5446_CHANNEL(14, 16, 0),
	.store_sample = ad5542_store_sample,
	},
	[ID_AD5601] = {
	.channel = AD5446_CHANNEL(8, 16, 6),
	.store_sample = ad5542_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5611] = {
	.channel = AD5446_CHANNEL(10, 16, 4),
	.store_sample = ad5542_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5621] = {
	.channel = AD5446_CHANNEL(12, 16, 2),
	.store_sample = ad5542_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5620_2500] = {
	.channel = AD5446_CHANNEL(12, 16, 2),
	.int_vref_mv = 2500,
	.store_sample = ad5620_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5620_1250] = {
	.channel = AD5446_CHANNEL(12, 16, 2),
	.int_vref_mv = 1250,
	.store_sample = ad5620_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5640_2500] = {
	.channel = AD5446_CHANNEL(14, 16, 0),
	.int_vref_mv = 2500,
	.store_sample = ad5620_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5640_1250] = {
	.channel = AD5446_CHANNEL(14, 16, 0),
	.int_vref_mv = 1250,
	.store_sample = ad5620_store_sample,
	.store_pwr_down = ad5620_store_pwr_down,
	},
	[ID_AD5660_2500] = {
	.channel = AD5446_CHANNEL(16, 16, 0),
	.int_vref_mv = 2500,
	.store_sample = ad5660_store_sample,
	.store_pwr_down = ad5660_store_pwr_down,
	},
	[ID_AD5660_1250] = {
	.channel = AD5446_CHANNEL(16, 16, 0),
	.int_vref_mv = 1250,
	.store_sample = ad5660_store_sample,
	.store_pwr_down = ad5660_store_pwr_down,
	},
	};

	static int ad5446_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int *val,
	int *val2,
	long m)
	{
	struct ad5446_state *st = iio_priv(indio_dev);
	unsigned long scale_uv;

	switch (m) {
	case IIO_CHAN_INFO_SCALE:
	scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
	*val = scale_uv / 1000;
	val2 = (scale_uv % 1000) 1000;
	return IIO_VAL_INT_PLUS_MICRO;

	}
	return -EINVAL;
	}

	static int ad5446_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val,
	int val2,
	long mask)
	{
	struct ad5446_state *st = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case 0:
	if (val >= (1 << chan->scan_type.realbits) \|\| val < 0)
	return -EINVAL;

	val <<= chan->scan_type.shift;
	mutex_lock(&indio_dev->mlock);
	st->cached_val = val;
	st->chip_info->store_sample(st, val);
	ret = spi_sync(st->spi, &st->msg);
	mutex_unlock(&indio_dev->mlock);
	break;
	default:
	ret = -EINVAL;
	}

	return ret;
	}

	static const struct iio_info ad5446_info = {
	.read_raw = ad5446_read_raw,
	.write_raw = ad5446_write_raw,
	.attrs = &ad5446_attribute_group,
	.driver_module = THIS_MODULE,
	};

	static int __devinit ad5446_probe(struct spi_device *spi)
	{
	struct ad5446_state *st;
	struct iio_dev *indio_dev;
	struct regulator *reg;
	int ret, voltage_uv = 0;

	reg = regulator_get(&spi->dev, "vcc");
	if (!IS_ERR(reg)) {
	ret = regulator_enable(reg);
	if (ret)
	goto error_put_reg;

	voltage_uv = regulator_get_voltage(reg);
	}

	indio_dev = iio_allocate_device(sizeof(*st));
	if (indio_dev == NULL) {
	ret = -ENOMEM;
	goto error_disable_reg;
	}
	st = iio_priv(indio_dev);
	st->chip_info =
	&ad5446_chip_info_tbl[spi_get_device_id(spi)->driver_data];

	spi_set_drvdata(spi, indio_dev);
	st->reg = reg;
	st->spi = spi;

	/* Estabilish that the iio_dev is a child of the spi device */
	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi_get_device_id(spi)->name;
	indio_dev->info = &ad5446_info;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = &st->chip_info->channel;
	indio_dev->num_channels = 1;

	/* Setup default message */

	st->xfer.tx_buf = &st->data;
	st->xfer.len = st->chip_info->channel.scan_type.storagebits / 8;

	spi_message_init(&st->msg);
	spi_message_add_tail(&st->xfer, &st->msg);

	switch (spi_get_device_id(spi)->driver_data) {
	case ID_AD5620_2500:
	case ID_AD5620_1250:
	case ID_AD5640_2500:
	case ID_AD5640_1250:
	case ID_AD5660_2500:
	case ID_AD5660_1250:
	st->vref_mv = st->chip_info->int_vref_mv;
	break;
	default:
	if (voltage_uv)
	st->vref_mv = voltage_uv / 1000;
	else
	dev_warn(&spi->dev,
	"reference voltage unspecified\n");
	}

	ret = iio_device_register(indio_dev);
	if (ret)
	goto error_free_device;

	return 0;

	error_free_device:
	iio_free_device(indio_dev);
	error_disable_reg:
	if (!IS_ERR(reg))
	regulator_disable(reg);
	error_put_reg:
	if (!IS_ERR(reg))
	regulator_put(reg);

	return ret;
	}

	static int ad5446_remove(struct spi_device *spi)
	{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct ad5446_state *st = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	if (!IS_ERR(st->reg)) {
	regulator_disable(st->reg);
	regulator_put(st->reg);
	}
	iio_free_device(indio_dev);

	return 0;
	}

	static const struct spi_device_id ad5446_id[] = {
	{"ad5444", ID_AD5444},
	{"ad5446", ID_AD5446},
	{"ad5512a", ID_AD5512A},
	{"ad5541a", ID_AD5541A},
	{"ad5542a", ID_AD5542A},
	{"ad5543", ID_AD5543},
	{"ad5553", ID_AD5553},
	{"ad5601", ID_AD5601},
	{"ad5611", ID_AD5611},
	{"ad5621", ID_AD5621},
	{"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
	{"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
	{"ad5640-2500", ID_AD5640_2500},
	{"ad5640-1250", ID_AD5640_1250},
	{"ad5660-2500", ID_AD5660_2500},
	{"ad5660-1250", ID_AD5660_1250},
	{}
	};
	MODULE_DEVICE_TABLE(spi, ad5446_id);

	static struct spi_driver ad5446_driver = {
	.driver = {
	.name = "ad5446",
	.owner = THIS_MODULE,
	},
	.probe = ad5446_probe,
	.remove = __devexit_p(ad5446_remove),
	.id_table = ad5446_id,
	};
	module_spi_driver(ad5446_driver);

	MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
	MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
	MODULE_LICENSE("GPL v2");