[linux.git] / drivers / staging / iio / dac / ad5791.c

/*
 * AD5760, AD5780, AD5781, AD5791 Voltage Output Digital to Analog Converter
 *
 * Copyright 2011 Analog Devices Inc.
 *
 * Licensed under the GPL-2.
 */

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

#include "../iio.h"
#include "../sysfs.h"
#include "dac.h"
#include "ad5791.h"

static int ad5791_spi_write(struct spi_device *spi, u8 addr, u32 val)
{
	union {
		u32 d32;
		u8 d8[4];
	} data;

	data.d32 = cpu_to_be32(AD5791_CMD_WRITE |
			      AD5791_ADDR(addr) |
			      (val & AD5791_DAC_MASK));

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

static int ad5791_spi_read(struct spi_device *spi, u8 addr, u32 *val)
{
	union {
		u32 d32;
		u8 d8[4];
	} data[3];
	int ret;
	struct spi_message msg;
	struct spi_transfer xfers[] = {
		{
			.tx_buf = &data[0].d8[1],
			.bits_per_word = 8,
			.len = 3,
			.cs_change = 1,
		}, {
			.tx_buf = &data[1].d8[1],
			.rx_buf = &data[2].d8[1],
			.bits_per_word = 8,
			.len = 3,
		},
	};

	data[0].d32 = cpu_to_be32(AD5791_CMD_READ |
			      AD5791_ADDR(addr));
	data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));

	spi_message_init(&msg);
	spi_message_add_tail(&xfers[0], &msg);
	spi_message_add_tail(&xfers[1], &msg);
	ret = spi_sync(spi, &msg);

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

	return ret;
}

#define AD5791_CHAN(bits, shift) {			\
	.type = IIO_VOLTAGE,				\
	.output = 1,					\
	.indexed = 1,					\
	.address = AD5791_ADDR_DAC0,			\
	.channel = 0,					\
	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT | \
		IIO_CHAN_INFO_OFFSET_SHARED_BIT,	\
	.scan_type = IIO_ST('u', bits, 24, shift)	\
}

static const struct iio_chan_spec ad5791_channels[] = {
	[ID_AD5760] = AD5791_CHAN(16, 4),
	[ID_AD5780] = AD5791_CHAN(18, 2),
	[ID_AD5781] = AD5791_CHAN(18, 2),
	[ID_AD5791] = AD5791_CHAN(20, 0)
};

static ssize_t ad5791_read_powerdown_mode(struct device *dev,
				      struct device_attribute *attr, char *buf)
{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5791_state *st = iio_priv(indio_dev);

	const char mode[][14] = {"6kohm_to_gnd", "three_state"};

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

static ssize_t ad5791_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 ad5791_state *st = iio_priv(indio_dev);
	int ret;

	if (sysfs_streq(buf, "6kohm_to_gnd"))
		st->pwr_down_mode = AD5791_DAC_PWRDN_6K;
	else if (sysfs_streq(buf, "three_state"))
		st->pwr_down_mode = AD5791_DAC_PWRDN_3STATE;
	else
		ret = -EINVAL;

	return ret ? ret : len;
}

static ssize_t ad5791_read_dac_powerdown(struct device *dev,
					   struct device_attribute *attr,
					   char *buf)
{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5791_state *st = iio_priv(indio_dev);

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

static ssize_t ad5791_write_dac_powerdown(struct device *dev,
					    struct device_attribute *attr,
					    const char *buf, size_t len)
{
	long readin;
	int ret;
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct ad5791_state *st = iio_priv(indio_dev);

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

	if (readin == 0) {
		st->pwr_down = false;
		st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
	} else if (readin == 1) {
		st->pwr_down = true;
		if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)
			st->ctrl |= AD5791_CTRL_OPGND;
		else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)
			st->ctrl |= AD5791_CTRL_DACTRI;
	} else
		ret = -EINVAL;

	ret = ad5791_spi_write(st->spi, AD5791_ADDR_CTRL, st->ctrl);

	return ret ? ret : len;
}

static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO |
			S_IWUSR, ad5791_read_powerdown_mode,
			ad5791_write_powerdown_mode, 0);

static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
			"6kohm_to_gnd three_state");

#define IIO_DEV_ATTR_DAC_POWERDOWN(_num, _show, _store, _addr)		\
	IIO_DEVICE_ATTR(out_voltage##_num##_powerdown,			\
			S_IRUGO | S_IWUSR, _show, _store, _addr)

static IIO_DEV_ATTR_DAC_POWERDOWN(0, ad5791_read_dac_powerdown,
				   ad5791_write_dac_powerdown, 0);

static struct attribute *ad5791_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 const struct attribute_group ad5791_attribute_group = {
	.attrs = ad5791_attributes,
};

static int ad5791_get_lin_comp(unsigned int span)
{
	if (span <= 10000)
		return AD5791_LINCOMP_0_10;
	else if (span <= 12000)
		return AD5791_LINCOMP_10_12;
	else if (span <= 16000)
		return AD5791_LINCOMP_12_16;
	else if (span <= 19000)
		return AD5791_LINCOMP_16_19;
	else
		return AD5791_LINCOMP_19_20;
}

static int ad5780_get_lin_comp(unsigned int span)
{
	if (span <= 10000)
		return AD5780_LINCOMP_0_10;
	else
		return AD5780_LINCOMP_10_20;
}
static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {
	[ID_AD5760] = {
		.get_lin_comp = ad5780_get_lin_comp,
	},
	[ID_AD5780] = {
		.get_lin_comp = ad5780_get_lin_comp,
	},
	[ID_AD5781] = {
		.get_lin_comp = ad5791_get_lin_comp,
	},
	[ID_AD5791] = {
		.get_lin_comp = ad5791_get_lin_comp,
	},
};

static int ad5791_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val,
			   int *val2,
			   long m)
{
	struct ad5791_state *st = iio_priv(indio_dev);
	u64 val64;
	int ret;

	switch (m) {
	case 0:
		ret = ad5791_spi_read(st->spi, chan->address, val);
		if (ret)
			return ret;
		*val &= AD5791_DAC_MASK;
		*val >>= chan->scan_type.shift;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = 0;
		*val2 = (((u64)st->vref_mv) * 1000000ULL) >> chan->scan_type.realbits;
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_OFFSET:
		val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);
		do_div(val64, st->vref_mv);
		*val = -val64;
		return IIO_VAL_INT;
	default:
		return -EINVAL;
	}

};


static int ad5791_write_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int val,
			    int val2,
			    long mask)
{
	struct ad5791_state *st = iio_priv(indio_dev);

	switch (mask) {
	case 0:
		val &= AD5791_RES_MASK(chan->scan_type.realbits);
		val <<= chan->scan_type.shift;

		return ad5791_spi_write(st->spi, chan->address, val);

	default:
		return -EINVAL;
	}
}

static const struct iio_info ad5791_info = {
	.read_raw = &ad5791_read_raw,
	.write_raw = &ad5791_write_raw,
	.attrs = &ad5791_attribute_group,
	.driver_module = THIS_MODULE,
};

static int __devinit ad5791_probe(struct spi_device *spi)
{
	struct ad5791_platform_data *pdata = spi->dev.platform_data;
	struct iio_dev *indio_dev;
	struct ad5791_state *st;
	int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;

	indio_dev = iio_allocate_device(sizeof(*st));
	if (indio_dev == NULL) {
		ret = -ENOMEM;
		goto error_ret;
	}
	st = iio_priv(indio_dev);
	st->reg_vdd = regulator_get(&spi->dev, "vdd");
	if (!IS_ERR(st->reg_vdd)) {
		ret = regulator_enable(st->reg_vdd);
		if (ret)
			goto error_put_reg_pos;

		pos_voltage_uv = regulator_get_voltage(st->reg_vdd);
	}

	st->reg_vss = regulator_get(&spi->dev, "vss");
	if (!IS_ERR(st->reg_vss)) {
		ret = regulator_enable(st->reg_vss);
		if (ret)
			goto error_put_reg_neg;

		neg_voltage_uv = regulator_get_voltage(st->reg_vss);
	}

	st->pwr_down = true;
	st->spi = spi;

	if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {
		st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;
		st->vref_neg_mv = neg_voltage_uv / 1000;
	} else if (pdata) {
		st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;
		st->vref_neg_mv = pdata->vref_neg_mv;
	} else {
		dev_warn(&spi->dev, "reference voltage unspecified\n");
	}

	ret = ad5791_spi_write(spi, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);
	if (ret)
		goto error_disable_reg_neg;

	st->chip_info =	&ad5791_chip_info_tbl[spi_get_device_id(spi)
					      ->driver_data];


	st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))
		  | ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) |
		  AD5791_CTRL_BIN2SC;

	ret = ad5791_spi_write(spi, AD5791_ADDR_CTRL, st->ctrl |
		AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
	if (ret)
		goto error_disable_reg_neg;

	spi_set_drvdata(spi, indio_dev);
	indio_dev->dev.parent = &spi->dev;
	indio_dev->info = &ad5791_info;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels
		= &ad5791_channels[spi_get_device_id(spi)->driver_data];
	indio_dev->num_channels = 1;
	indio_dev->name = spi_get_device_id(st->spi)->name;
	ret = iio_device_register(indio_dev);
	if (ret)
		goto error_disable_reg_neg;

	return 0;

error_disable_reg_neg:
	if (!IS_ERR(st->reg_vss))
		regulator_disable(st->reg_vss);
error_put_reg_neg:
	if (!IS_ERR(st->reg_vss))
		regulator_put(st->reg_vss);

	if (!IS_ERR(st->reg_vdd))
		regulator_disable(st->reg_vdd);
error_put_reg_pos:
	if (!IS_ERR(st->reg_vdd))
		regulator_put(st->reg_vdd);
	iio_free_device(indio_dev);
error_ret:

	return ret;
}

static int __devexit ad5791_remove(struct spi_device *spi)
{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct ad5791_state *st = iio_priv(indio_dev);

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

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

	return 0;
}

static const struct spi_device_id ad5791_id[] = {
	{"ad5760", ID_AD5760},
	{"ad5780", ID_AD5780},
	{"ad5781", ID_AD5781},
	{"ad5791", ID_AD5791},
	{}
};
MODULE_DEVICE_TABLE(spi, ad5791_id);

static struct spi_driver ad5791_driver = {
	.driver = {
		   .name = "ad5791",
		   .owner = THIS_MODULE,
		   },
	.probe = ad5791_probe,
	.remove = __devexit_p(ad5791_remove),
	.id_table = ad5791_id,
};

static __init int ad5791_spi_init(void)
{
	return spi_register_driver(&ad5791_driver);
}
module_init(ad5791_spi_init);

static __exit void ad5791_spi_exit(void)
{
	spi_unregister_driver(&ad5791_driver);
}
module_exit(ad5791_spi_exit);

MODULE_AUTHOR("Michael Hennerich <[email protected]>");
MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5791 DAC");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
69d900a6	1	/*
ba1c2bb2	2	* AD5760, AD5780, AD5781, AD5791 Voltage Output Digital to Analog Converter
69d900a6 MH	3	*
	4	* Copyright 2011 Analog Devices Inc.
	5	*
	6	* Licensed under the GPL-2.
	7	*/
	8
	9	#include <linux/interrupt.h>
69d900a6 MH	10	#include <linux/fs.h>
	11	#include <linux/device.h>
	12	#include <linux/kernel.h>
	13	#include <linux/spi/spi.h>
	14	#include <linux/slab.h>
	15	#include <linux/sysfs.h>
	16	#include <linux/regulator/consumer.h>
99c97852	17	#include <linux/module.h>
69d900a6 MH	18
	19	#include "../iio.h"
	20	#include "../sysfs.h"
	21	#include "dac.h"
	22	#include "ad5791.h"
	23
	24	static int ad5791_spi_write(struct spi_device *spi, u8 addr, u32 val)
	25	{
	26	union {
	27	u32 d32;
	28	u8 d8[4];
	29	} data;
	30
	31	data.d32 = cpu_to_be32(AD5791_CMD_WRITE \|
	32	AD5791_ADDR(addr) \|
	33	(val & AD5791_DAC_MASK));
	34
	35	return spi_write(spi, &data.d8[1], 3);
	36	}
	37
	38	static int ad5791_spi_read(struct spi_device spi, u8 addr, u32 val)
	39	{
	40	union {
	41	u32 d32;
	42	u8 d8[4];
	43	} data[3];
	44	int ret;
	45	struct spi_message msg;
	46	struct spi_transfer xfers[] = {
	47	{
	48	.tx_buf = &data[0].d8[1],
	49	.bits_per_word = 8,
	50	.len = 3,
	51	.cs_change = 1,
	52	}, {
	53	.tx_buf = &data[1].d8[1],
	54	.rx_buf = &data[2].d8[1],
	55	.bits_per_word = 8,
	56	.len = 3,
	57	},
	58	};
	59
	60	data[0].d32 = cpu_to_be32(AD5791_CMD_READ \|
	61	AD5791_ADDR(addr));
	62	data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));
	63
	64	spi_message_init(&msg);
	65	spi_message_add_tail(&xfers[0], &msg);
	66	spi_message_add_tail(&xfers[1], &msg);
	67	ret = spi_sync(spi, &msg);
	68
	69	*val = be32_to_cpu(data[2].d32);
	70
	71	return ret;
	72	}
	73
c5b99396 JC	74	#define AD5791_CHAN(bits, shift) { \
	75	.type = IIO_VOLTAGE, \
	76	.output = 1, \
	77	.indexed = 1, \
	78	.address = AD5791_ADDR_DAC0, \
	79	.channel = 0, \
c8a9f805 JC	80	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT \| \
c8a9f805 JC	81	IIO_CHAN_INFO_OFFSET_SHARED_BIT, \
c5b99396	82	.scan_type = IIO_ST('u', bits, 24, shift) \
69d900a6 MH	83	}
69d900a6 MH	84
c5b99396 JC	85	static const struct iio_chan_spec ad5791_channels[] = {
	86	[ID_AD5760] = AD5791_CHAN(16, 4),
	87	[ID_AD5780] = AD5791_CHAN(18, 2),
	88	[ID_AD5781] = AD5791_CHAN(18, 2),
	89	[ID_AD5791] = AD5791_CHAN(20, 0)
	90	};
69d900a6 MH	91
	92	static ssize_t ad5791_read_powerdown_mode(struct device *dev,
	93	struct device_attribute attr, char buf)
	94	{
	95	struct iio_dev *indio_dev = dev_get_drvdata(dev);
f5730d52	96	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6 MH	97
	98	const char mode[][14] = {"6kohm_to_gnd", "three_state"};
	99
	100	return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
	101	}
	102
	103	static ssize_t ad5791_write_powerdown_mode(struct device *dev,
	104	struct device_attribute *attr,
	105	const char *buf, size_t len)
	106	{
	107	struct iio_dev *indio_dev = dev_get_drvdata(dev);
f5730d52	108	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6 MH	109	int ret;
	110
	111	if (sysfs_streq(buf, "6kohm_to_gnd"))
	112	st->pwr_down_mode = AD5791_DAC_PWRDN_6K;
	113	else if (sysfs_streq(buf, "three_state"))
	114	st->pwr_down_mode = AD5791_DAC_PWRDN_3STATE;
	115	else
	116	ret = -EINVAL;
	117
	118	return ret ? ret : len;
	119	}
	120
	121	static ssize_t ad5791_read_dac_powerdown(struct device *dev,
	122	struct device_attribute *attr,
	123	char *buf)
	124	{
	125	struct iio_dev *indio_dev = dev_get_drvdata(dev);
f5730d52	126	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6 MH	127
	128	return sprintf(buf, "%d\n", st->pwr_down);
	129	}
	130
	131	static ssize_t ad5791_write_dac_powerdown(struct device *dev,
	132	struct device_attribute *attr,
	133	const char *buf, size_t len)
	134	{
	135	long readin;
	136	int ret;
	137	struct iio_dev *indio_dev = dev_get_drvdata(dev);
f5730d52	138	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6 MH	139
	140	ret = strict_strtol(buf, 10, &readin);
	141	if (ret)
	142	return ret;
	143
	144	if (readin == 0) {
	145	st->pwr_down = false;
	146	st->ctrl &= ~(AD5791_CTRL_OPGND \| AD5791_CTRL_DACTRI);
	147	} else if (readin == 1) {
	148	st->pwr_down = true;
	149	if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)
	150	st->ctrl \|= AD5791_CTRL_OPGND;
	151	else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)
	152	st->ctrl \|= AD5791_CTRL_DACTRI;
	153	} else
	154	ret = -EINVAL;
	155
	156	ret = ad5791_spi_write(st->spi, AD5791_ADDR_CTRL, st->ctrl);
	157
	158	return ret ? ret : len;
	159	}
	160
f1a61a88	161	static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO \|
69d900a6 MH	162	S_IWUSR, ad5791_read_powerdown_mode,
	163	ad5791_write_powerdown_mode, 0);
	164
f1a61a88	165	static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
69d900a6 MH	166	"6kohm_to_gnd three_state");
	167
	168	#define IIO_DEV_ATTR_DAC_POWERDOWN(_num, _show, _store, _addr) \
f1a61a88	169	IIO_DEVICE_ATTR(out_voltage##_num##_powerdown, \
69d900a6 MH	170	S_IRUGO \| S_IWUSR, _show, _store, _addr)
	171
	172	static IIO_DEV_ATTR_DAC_POWERDOWN(0, ad5791_read_dac_powerdown,
	173	ad5791_write_dac_powerdown, 0);
	174
	175	static struct attribute *ad5791_attributes[] = {
f1a61a88 LPC	176	&iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
	177	&iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
	178	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
69d900a6 MH	179	NULL,
	180	};
	181
	182	static const struct attribute_group ad5791_attribute_group = {
	183	.attrs = ad5791_attributes,
	184	};
	185
69d900a6 MH	186	static int ad5791_get_lin_comp(unsigned int span)
	187	{
	188	if (span <= 10000)
	189	return AD5791_LINCOMP_0_10;
	190	else if (span <= 12000)
	191	return AD5791_LINCOMP_10_12;
	192	else if (span <= 16000)
	193	return AD5791_LINCOMP_12_16;
	194	else if (span <= 19000)
	195	return AD5791_LINCOMP_16_19;
	196	else
	197	return AD5791_LINCOMP_19_20;
	198	}
	199
ba1c2bb2 MH	200	static int ad5780_get_lin_comp(unsigned int span)
	201	{
	202	if (span <= 10000)
	203	return AD5780_LINCOMP_0_10;
	204	else
	205	return AD5780_LINCOMP_10_20;
	206	}
ba1c2bb2 MH	207	static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {
ba1c2bb2 MH	208	[ID_AD5760] = {
ba1c2bb2 MH	209	.get_lin_comp = ad5780_get_lin_comp,
	210	},
	211	[ID_AD5780] = {
ba1c2bb2 MH	212	.get_lin_comp = ad5780_get_lin_comp,
	213	},
	214	[ID_AD5781] = {
ba1c2bb2 MH	215	.get_lin_comp = ad5791_get_lin_comp,
	216	},
	217	[ID_AD5791] = {
ba1c2bb2 MH	218	.get_lin_comp = ad5791_get_lin_comp,
	219	},
	220	};
	221
c5b99396 JC	222	static int ad5791_read_raw(struct iio_dev *indio_dev,
	223	struct iio_chan_spec const *chan,
	224	int *val,
	225	int *val2,
	226	long m)
	227	{
	228	struct ad5791_state *st = iio_priv(indio_dev);
9dc9961d	229	u64 val64;
c5b99396 JC	230	int ret;
	231
	232	switch (m) {
	233	case 0:
	234	ret = ad5791_spi_read(st->spi, chan->address, val);
	235	if (ret)
	236	return ret;
	237	*val &= AD5791_DAC_MASK;
	238	*val >>= chan->scan_type.shift;
c5b99396	239	return IIO_VAL_INT;
c8a9f805	240	case IIO_CHAN_INFO_SCALE:
c5b99396	241	*val = 0;
75bb23a2	242	val2 = (((u64)st->vref_mv) 1000000ULL) >> chan->scan_type.realbits;
c5b99396	243	return IIO_VAL_INT_PLUS_MICRO;
c8a9f805	244	case IIO_CHAN_INFO_OFFSET:
9dc9961d LPC	245	val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);
	246	do_div(val64, st->vref_mv);
	247	*val = -val64;
	248	return IIO_VAL_INT;
c5b99396 JC	249	default:
	250	return -EINVAL;
	251	}
	252
	253	};
	254
	255
	256	static int ad5791_write_raw(struct iio_dev *indio_dev,
	257	struct iio_chan_spec const *chan,
	258	int val,
	259	int val2,
	260	long mask)
	261	{
	262	struct ad5791_state *st = iio_priv(indio_dev);
	263
	264	switch (mask) {
	265	case 0:
021c0a38	266	val &= AD5791_RES_MASK(chan->scan_type.realbits);
c5b99396 JC	267	val <<= chan->scan_type.shift;
	268
	269	return ad5791_spi_write(st->spi, chan->address, val);
	270
	271	default:
	272	return -EINVAL;
	273	}
	274	}
	275
6fe8135f	276	static const struct iio_info ad5791_info = {
c5b99396 JC	277	.read_raw = &ad5791_read_raw,
c5b99396 JC	278	.write_raw = &ad5791_write_raw,
6fe8135f JC	279	.attrs = &ad5791_attribute_group,
	280	.driver_module = THIS_MODULE,
	281	};
	282
69d900a6 MH	283	static int __devinit ad5791_probe(struct spi_device *spi)
	284	{
	285	struct ad5791_platform_data *pdata = spi->dev.platform_data;
f5730d52	286	struct iio_dev *indio_dev;
69d900a6 MH	287	struct ad5791_state *st;
	288	int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;
	289
26a54797 JC	290	indio_dev = iio_allocate_device(sizeof(*st));
	291	if (indio_dev == NULL) {
	292	ret = -ENOMEM;
	293	goto error_ret;
	294	}
	295	st = iio_priv(indio_dev);
	296	st->reg_vdd = regulator_get(&spi->dev, "vdd");
	297	if (!IS_ERR(st->reg_vdd)) {
	298	ret = regulator_enable(st->reg_vdd);
69d900a6 MH	299	if (ret)
	300	goto error_put_reg_pos;
	301
26a54797	302	pos_voltage_uv = regulator_get_voltage(st->reg_vdd);
69d900a6 MH	303	}
69d900a6 MH	304
26a54797 JC	305	st->reg_vss = regulator_get(&spi->dev, "vss");
	306	if (!IS_ERR(st->reg_vss)) {
	307	ret = regulator_enable(st->reg_vss);
69d900a6 MH	308	if (ret)
	309	goto error_put_reg_neg;
	310
26a54797	311	neg_voltage_uv = regulator_get_voltage(st->reg_vss);
69d900a6 MH	312	}
69d900a6 MH	313
f5730d52 JC	314	st->pwr_down = true;
	315	st->spi = spi;
	316
9dc9961d LPC	317	if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {
	318	st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;
	319	st->vref_neg_mv = neg_voltage_uv / 1000;
	320	} else if (pdata) {
	321	st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;
	322	st->vref_neg_mv = pdata->vref_neg_mv;
	323	} else {
69d900a6	324	dev_warn(&spi->dev, "reference voltage unspecified\n");
9dc9961d	325	}
69d900a6 MH	326
	327	ret = ad5791_spi_write(spi, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);
	328	if (ret)
26a54797	329	goto error_disable_reg_neg;
69d900a6	330
c5b99396 JC	331	st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi)
c5b99396 JC	332	->driver_data];
69d900a6 MH	333
69d900a6 MH	334
ba1c2bb2 MH	335	st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))
ba1c2bb2 MH	336	\| ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) \|
69d900a6 MH	337	AD5791_CTRL_BIN2SC;
	338
	339	ret = ad5791_spi_write(spi, AD5791_ADDR_CTRL, st->ctrl \|
	340	AD5791_CTRL_OPGND \| AD5791_CTRL_DACTRI);
	341	if (ret)
26a54797	342	goto error_disable_reg_neg;
69d900a6	343
f5730d52 JC	344	spi_set_drvdata(spi, indio_dev);
	345	indio_dev->dev.parent = &spi->dev;
	346	indio_dev->info = &ad5791_info;
	347	indio_dev->modes = INDIO_DIRECT_MODE;
c5b99396 JC	348	indio_dev->channels
	349	= &ad5791_channels[spi_get_device_id(spi)->driver_data];
	350	indio_dev->num_channels = 1;
	351	indio_dev->name = spi_get_device_id(st->spi)->name;
f5730d52	352	ret = iio_device_register(indio_dev);
69d900a6	353	if (ret)
26a54797	354	goto error_disable_reg_neg;
69d900a6 MH	355
	356	return 0;
	357
69d900a6	358	error_disable_reg_neg:
26a54797 JC	359	if (!IS_ERR(st->reg_vss))
26a54797 JC	360	regulator_disable(st->reg_vss);
69d900a6	361	error_put_reg_neg:
26a54797 JC	362	if (!IS_ERR(st->reg_vss))
26a54797 JC	363	regulator_put(st->reg_vss);
69d900a6	364
26a54797 JC	365	if (!IS_ERR(st->reg_vdd))
26a54797 JC	366	regulator_disable(st->reg_vdd);
69d900a6	367	error_put_reg_pos:
26a54797 JC	368	if (!IS_ERR(st->reg_vdd))
	369	regulator_put(st->reg_vdd);
	370	iio_free_device(indio_dev);
	371	error_ret:
69d900a6	372
69d900a6 MH	373	return ret;
	374	}
	375
	376	static int __devexit ad5791_remove(struct spi_device *spi)
	377	{
f5730d52 JC	378	struct iio_dev *indio_dev = spi_get_drvdata(spi);
f5730d52 JC	379	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6	380
d2fffd6c	381	iio_device_unregister(indio_dev);
69d900a6	382	if (!IS_ERR(st->reg_vdd)) {
26a54797 JC	383	regulator_disable(st->reg_vdd);
26a54797 JC	384	regulator_put(st->reg_vdd);
69d900a6 MH	385	}
	386
	387	if (!IS_ERR(st->reg_vss)) {
26a54797 JC	388	regulator_disable(st->reg_vss);
26a54797 JC	389	regulator_put(st->reg_vss);
69d900a6	390	}
d2fffd6c	391	iio_free_device(indio_dev);
26d25ae3	392
69d900a6 MH	393	return 0;
	394	}
	395
	396	static const struct spi_device_id ad5791_id[] = {
ba1c2bb2 MH	397	{"ad5760", ID_AD5760},
ba1c2bb2 MH	398	{"ad5780", ID_AD5780},
69d900a6	399	{"ad5781", ID_AD5781},
ba1c2bb2	400	{"ad5791", ID_AD5791},
69d900a6 MH	401	{}
69d900a6 MH	402	};
55e4390c	403	MODULE_DEVICE_TABLE(spi, ad5791_id);
69d900a6 MH	404
	405	static struct spi_driver ad5791_driver = {
	406	.driver = {
	407	.name = "ad5791",
	408	.owner = THIS_MODULE,
	409	},
	410	.probe = ad5791_probe,
	411	.remove = __devexit_p(ad5791_remove),
	412	.id_table = ad5791_id,
	413	};
	414
	415	static __init int ad5791_spi_init(void)
	416	{
	417	return spi_register_driver(&ad5791_driver);
	418	}
	419	module_init(ad5791_spi_init);
	420
	421	static __exit void ad5791_spi_exit(void)
	422	{
	423	spi_unregister_driver(&ad5791_driver);
	424	}
	425	module_exit(ad5791_spi_exit);
	426
	427	MODULE_AUTHOR("Michael Hennerich <[email protected]>");
ba1c2bb2	428	MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5791 DAC");
69d900a6	429	MODULE_LICENSE("GPL v2");