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

/*
 * AD5760, AD5780, AD5781, AD5790, 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 <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/dac/ad5791.h>

#define AD5791_RES_MASK(x)		((1 << (x)) - 1)
#define AD5791_DAC_MASK			AD5791_RES_MASK(20)
#define AD5791_DAC_MSB			(1 << 19)

#define AD5791_CMD_READ			(1 << 23)
#define AD5791_CMD_WRITE		(0 << 23)
#define AD5791_ADDR(addr)		((addr) << 20)

/* Registers */
#define AD5791_ADDR_NOOP		0
#define AD5791_ADDR_DAC0		1
#define AD5791_ADDR_CTRL		2
#define AD5791_ADDR_CLRCODE		3
#define AD5791_ADDR_SW_CTRL		4

/* Control Register */
#define AD5791_CTRL_RBUF		(1 << 1)
#define AD5791_CTRL_OPGND		(1 << 2)
#define AD5791_CTRL_DACTRI		(1 << 3)
#define AD5791_CTRL_BIN2SC		(1 << 4)
#define AD5791_CTRL_SDODIS		(1 << 5)
#define AD5761_CTRL_LINCOMP(x)		((x) << 6)

#define AD5791_LINCOMP_0_10		0
#define AD5791_LINCOMP_10_12		1
#define AD5791_LINCOMP_12_16		2
#define AD5791_LINCOMP_16_19		3
#define AD5791_LINCOMP_19_20		12

#define AD5780_LINCOMP_0_10		0
#define AD5780_LINCOMP_10_20		12

/* Software Control Register */
#define AD5791_SWCTRL_LDAC		(1 << 0)
#define AD5791_SWCTRL_CLR		(1 << 1)
#define AD5791_SWCTRL_RESET		(1 << 2)

#define AD5791_DAC_PWRDN_6K		0
#define AD5791_DAC_PWRDN_3STATE		1

/**
 * struct ad5791_chip_info - chip specific information
 * @get_lin_comp:	function pointer to the device specific function
 */

struct ad5791_chip_info {
	int (*get_lin_comp)	(unsigned int span);
};

/**
 * struct ad5791_state - driver instance specific data
 * @us:			spi_device
 * @reg_vdd:		positive supply regulator
 * @reg_vss:		negative supply regulator
 * @chip_info:		chip model specific constants
 * @vref_mv:		actual reference voltage used
 * @vref_neg_mv:	voltage of the negative supply
 * @pwr_down_mode	current power down mode
 */

struct ad5791_state {
	struct spi_device		*spi;
	struct regulator		*reg_vdd;
	struct regulator		*reg_vss;
	const struct ad5791_chip_info	*chip_info;
	unsigned short			vref_mv;
	unsigned int			vref_neg_mv;
	unsigned			ctrl;
	unsigned			pwr_down_mode;
	bool				pwr_down;
};

/**
 * ad5791_supported_device_ids:
 */

enum ad5791_supported_device_ids {
	ID_AD5760,
	ID_AD5780,
	ID_AD5781,
	ID_AD5791,
};

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_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));

	ret = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));

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

	return ret;
}

static const char * const ad5791_powerdown_modes[] = {
	"6kohm_to_gnd",
	"three_state",
};

static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan)
{
	struct ad5791_state *st = iio_priv(indio_dev);

	return st->pwr_down_mode;
}

static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, unsigned int mode)
{
	struct ad5791_state *st = iio_priv(indio_dev);

	st->pwr_down_mode = mode;

	return 0;
}

static const struct iio_enum ad5791_powerdown_mode_enum = {
	.items = ad5791_powerdown_modes,
	.num_items = ARRAY_SIZE(ad5791_powerdown_modes),
	.get = ad5791_get_powerdown_mode,
	.set = ad5791_set_powerdown_mode,
};

static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev,
	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
	struct ad5791_state *st = iio_priv(indio_dev);

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

static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev,
	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
	 size_t len)
{
	bool pwr_down;
	int ret;
	struct ad5791_state *st = iio_priv(indio_dev);

	ret = strtobool(buf, &pwr_down);
	if (ret)
		return ret;

	if (!pwr_down) {
		st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
	} else {
		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;
	}
	st->pwr_down = pwr_down;

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

	return ret ? ret : len;
}

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 IIO_CHAN_INFO_RAW:
		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 const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
	{
		.name = "powerdown",
		.shared = true,
		.read = ad5791_read_dac_powerdown,
		.write = ad5791_write_dac_powerdown,
	},
	IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum),
	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
	{ },
};

#define AD5791_CHAN(bits, shift) {			\
	.type = IIO_VOLTAGE,				\
	.output = 1,					\
	.indexed = 1,					\
	.address = AD5791_ADDR_DAC0,			\
	.channel = 0,					\
	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |	\
		IIO_CHAN_INFO_SCALE_SHARED_BIT |	\
		IIO_CHAN_INFO_OFFSET_SHARED_BIT,	\
	.scan_type = IIO_ST('u', bits, 24, shift),	\
	.ext_info = ad5791_ext_info,			\
}

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 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 IIO_CHAN_INFO_RAW:
		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,
	.driver_module = THIS_MODULE,
};

static int 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_device_alloc(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;

		ret = regulator_get_voltage(st->reg_vdd);
		if (ret < 0)
			goto error_disable_reg_pos;

		pos_voltage_uv = ret;
	}

	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;

		ret = regulator_get_voltage(st->reg_vss);
		if (ret < 0)
			goto error_disable_reg_neg;

		neg_voltage_uv = ret;
	}

	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);

error_disable_reg_pos:
	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_device_free(indio_dev);
error_ret:

	return ret;
}

static int 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_device_free(indio_dev);

	return 0;
}

static const struct spi_device_id ad5791_id[] = {
	{"ad5760", ID_AD5760},
	{"ad5780", ID_AD5780},
	{"ad5781", ID_AD5781},
	{"ad5790", ID_AD5791},
	{"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 = ad5791_remove,
	.id_table = ad5791_id,
};
module_spi_driver(ad5791_driver);

MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
69d900a6	1	/*
9d41c5bb LPC	2	* AD5760, AD5780, AD5781, AD5790, AD5791 Voltage Output Digital to Analog
9d41c5bb LPC	3	* Converter
69d900a6 MH	4	*
	5	* Copyright 2011 Analog Devices Inc.
	6	*
	7	* Licensed under the GPL-2.
	8	*/
	9
	10	#include <linux/interrupt.h>
69d900a6 MH	11	#include <linux/fs.h>
	12	#include <linux/device.h>
	13	#include <linux/kernel.h>
	14	#include <linux/spi/spi.h>
	15	#include <linux/slab.h>
	16	#include <linux/sysfs.h>
	17	#include <linux/regulator/consumer.h>
99c97852	18	#include <linux/module.h>
69d900a6	19
06458e27 JC	20	#include <linux/iio/iio.h>
06458e27 JC	21	#include <linux/iio/sysfs.h>
dbdc025b	22	#include <linux/iio/dac/ad5791.h>
69d900a6	23
20374d1a LPC	24	#define AD5791_RES_MASK(x) ((1 << (x)) - 1)
	25	#define AD5791_DAC_MASK AD5791_RES_MASK(20)
	26	#define AD5791_DAC_MSB (1 << 19)
	27
	28	#define AD5791_CMD_READ (1 << 23)
	29	#define AD5791_CMD_WRITE (0 << 23)
	30	#define AD5791_ADDR(addr) ((addr) << 20)
	31
	32	/* Registers */
	33	#define AD5791_ADDR_NOOP 0
	34	#define AD5791_ADDR_DAC0 1
	35	#define AD5791_ADDR_CTRL 2
	36	#define AD5791_ADDR_CLRCODE 3
	37	#define AD5791_ADDR_SW_CTRL 4
	38
	39	/* Control Register */
	40	#define AD5791_CTRL_RBUF (1 << 1)
	41	#define AD5791_CTRL_OPGND (1 << 2)
	42	#define AD5791_CTRL_DACTRI (1 << 3)
	43	#define AD5791_CTRL_BIN2SC (1 << 4)
	44	#define AD5791_CTRL_SDODIS (1 << 5)
	45	#define AD5761_CTRL_LINCOMP(x) ((x) << 6)
	46
	47	#define AD5791_LINCOMP_0_10 0
	48	#define AD5791_LINCOMP_10_12 1
	49	#define AD5791_LINCOMP_12_16 2
	50	#define AD5791_LINCOMP_16_19 3
	51	#define AD5791_LINCOMP_19_20 12
	52
	53	#define AD5780_LINCOMP_0_10 0
	54	#define AD5780_LINCOMP_10_20 12
	55
	56	/* Software Control Register */
	57	#define AD5791_SWCTRL_LDAC (1 << 0)
	58	#define AD5791_SWCTRL_CLR (1 << 1)
	59	#define AD5791_SWCTRL_RESET (1 << 2)
	60
	61	#define AD5791_DAC_PWRDN_6K 0
	62	#define AD5791_DAC_PWRDN_3STATE 1
	63
	64	/**
	65	* struct ad5791_chip_info - chip specific information
	66	* @get_lin_comp: function pointer to the device specific function
	67	*/
	68
	69	struct ad5791_chip_info {
	70	int (*get_lin_comp) (unsigned int span);
	71	};
	72
	73	/**
	74	* struct ad5791_state - driver instance specific data
	75	* @us: spi_device
	76	* @reg_vdd: positive supply regulator
	77	* @reg_vss: negative supply regulator
	78	* @chip_info: chip model specific constants
	79	* @vref_mv: actual reference voltage used
	80	* @vref_neg_mv: voltage of the negative supply
	81	* @pwr_down_mode current power down mode
	82	*/
	83
	84	struct ad5791_state {
	85	struct spi_device *spi;
	86	struct regulator *reg_vdd;
	87	struct regulator *reg_vss;
88	const struct ad5791_chip_info *chip_info;
89	unsigned short vref_mv;
90	unsigned int vref_neg_mv;
91	unsigned ctrl;
92	unsigned pwr_down_mode;
93	bool pwr_down;
94	};
95
96	/**
97	* ad5791_supported_device_ids:
98	*/
99
100	enum ad5791_supported_device_ids {
101	ID_AD5760,
102	ID_AD5780,
103	ID_AD5781,
104	ID_AD5791,
105	};
106
69d900a6 MH	107	static int ad5791_spi_write(struct spi_device *spi, u8 addr, u32 val)
	108	{
	109	union {
	110	u32 d32;
	111	u8 d8[4];
	112	} data;
	113
	114	data.d32 = cpu_to_be32(AD5791_CMD_WRITE \|
	115	AD5791_ADDR(addr) \|
	116	(val & AD5791_DAC_MASK));
	117
	118	return spi_write(spi, &data.d8[1], 3);
	119	}
	120
	121	static int ad5791_spi_read(struct spi_device spi, u8 addr, u32 val)
	122	{
	123	union {
	124	u32 d32;
	125	u8 d8[4];
	126	} data[3];
	127	int ret;
69d900a6 MH	128	struct spi_transfer xfers[] = {
	129	{
	130	.tx_buf = &data[0].d8[1],
	131	.bits_per_word = 8,
	132	.len = 3,
	133	.cs_change = 1,
	134	}, {
	135	.tx_buf = &data[1].d8[1],
	136	.rx_buf = &data[2].d8[1],
	137	.bits_per_word = 8,
	138	.len = 3,
	139	},
	140	};
	141
	142	data[0].d32 = cpu_to_be32(AD5791_CMD_READ \|
	143	AD5791_ADDR(addr));
	144	data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));
	145
14543a00	146	ret = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
69d900a6 MH	147
	148	*val = be32_to_cpu(data[2].d32);
	149
	150	return ret;
	151	}
	152
4571b39b LPC	153	static const char * const ad5791_powerdown_modes[] = {
	154	"6kohm_to_gnd",
	155	"three_state",
c5b99396	156	};
69d900a6	157
4571b39b LPC	158	static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev,
4571b39b LPC	159	const struct iio_chan_spec *chan)
69d900a6	160	{
f5730d52	161	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6	162
4571b39b	163	return st->pwr_down_mode;
69d900a6 MH	164	}
69d900a6 MH	165
4571b39b LPC	166	static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev,
4571b39b LPC	167	const struct iio_chan_spec *chan, unsigned int mode)
69d900a6	168	{
f5730d52	169	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6	170
4571b39b	171	st->pwr_down_mode = mode;
69d900a6	172
4571b39b	173	return 0;
69d900a6 MH	174	}
69d900a6 MH	175
4571b39b LPC	176	static const struct iio_enum ad5791_powerdown_mode_enum = {
	177	.items = ad5791_powerdown_modes,
	178	.num_items = ARRAY_SIZE(ad5791_powerdown_modes),
	179	.get = ad5791_get_powerdown_mode,
	180	.set = ad5791_set_powerdown_mode,
	181	};
	182
	183	static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev,
	184	uintptr_t private, const struct iio_chan_spec chan, char buf)
69d900a6	185	{
f5730d52	186	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6 MH	187
	188	return sprintf(buf, "%d\n", st->pwr_down);
	189	}
	190
4571b39b LPC	191	static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev,
	192	uintptr_t private, const struct iio_chan_spec chan, const char buf,
	193	size_t len)
69d900a6	194	{
4468cb55	195	bool pwr_down;
69d900a6	196	int ret;
f5730d52	197	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6	198
4468cb55	199	ret = strtobool(buf, &pwr_down);
69d900a6 MH	200	if (ret)
	201	return ret;
	202
4468cb55	203	if (!pwr_down) {
69d900a6	204	st->ctrl &= ~(AD5791_CTRL_OPGND \| AD5791_CTRL_DACTRI);
4468cb55	205	} else {
69d900a6 MH	206	if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)
	207	st->ctrl \|= AD5791_CTRL_OPGND;
	208	else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)
	209	st->ctrl \|= AD5791_CTRL_DACTRI;
4468cb55 LPC	210	}
4468cb55 LPC	211	st->pwr_down = pwr_down;
69d900a6 MH	212
	213	ret = ad5791_spi_write(st->spi, AD5791_ADDR_CTRL, st->ctrl);
	214
	215	return ret ? ret : len;
	216	}
	217
69d900a6 MH	218	static int ad5791_get_lin_comp(unsigned int span)
	219	{
	220	if (span <= 10000)
	221	return AD5791_LINCOMP_0_10;
	222	else if (span <= 12000)
	223	return AD5791_LINCOMP_10_12;
	224	else if (span <= 16000)
	225	return AD5791_LINCOMP_12_16;
	226	else if (span <= 19000)
	227	return AD5791_LINCOMP_16_19;
	228	else
	229	return AD5791_LINCOMP_19_20;
	230	}
	231
ba1c2bb2 MH	232	static int ad5780_get_lin_comp(unsigned int span)
	233	{
	234	if (span <= 10000)
	235	return AD5780_LINCOMP_0_10;
	236	else
	237	return AD5780_LINCOMP_10_20;
	238	}
ba1c2bb2 MH	239	static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {
ba1c2bb2 MH	240	[ID_AD5760] = {
ba1c2bb2 MH	241	.get_lin_comp = ad5780_get_lin_comp,
	242	},
	243	[ID_AD5780] = {
ba1c2bb2 MH	244	.get_lin_comp = ad5780_get_lin_comp,
	245	},
	246	[ID_AD5781] = {
ba1c2bb2 MH	247	.get_lin_comp = ad5791_get_lin_comp,
	248	},
	249	[ID_AD5791] = {
ba1c2bb2 MH	250	.get_lin_comp = ad5791_get_lin_comp,
	251	},
	252	};
	253
c5b99396 JC	254	static int ad5791_read_raw(struct iio_dev *indio_dev,
	255	struct iio_chan_spec const *chan,
	256	int *val,
	257	int *val2,
	258	long m)
	259	{
	260	struct ad5791_state *st = iio_priv(indio_dev);
9dc9961d	261	u64 val64;
c5b99396 JC	262	int ret;
	263
	264	switch (m) {
09f4eb40	265	case IIO_CHAN_INFO_RAW:
c5b99396 JC	266	ret = ad5791_spi_read(st->spi, chan->address, val);
	267	if (ret)
	268	return ret;
	269	*val &= AD5791_DAC_MASK;
	270	*val >>= chan->scan_type.shift;
c5b99396	271	return IIO_VAL_INT;
c8a9f805	272	case IIO_CHAN_INFO_SCALE:
c5b99396	273	*val = 0;
75bb23a2	274	val2 = (((u64)st->vref_mv) 1000000ULL) >> chan->scan_type.realbits;
c5b99396	275	return IIO_VAL_INT_PLUS_MICRO;
c8a9f805	276	case IIO_CHAN_INFO_OFFSET:
9dc9961d LPC	277	val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);
	278	do_div(val64, st->vref_mv);
	279	*val = -val64;
	280	return IIO_VAL_INT;
c5b99396 JC	281	default:
	282	return -EINVAL;
	283	}
	284
	285	};
	286
4571b39b LPC	287	static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
	288	{
	289	.name = "powerdown",
	290	.shared = true,
	291	.read = ad5791_read_dac_powerdown,
	292	.write = ad5791_write_dac_powerdown,
	293	},
	294	IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum),
	295	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
	296	{ },
	297	};
	298
	299	#define AD5791_CHAN(bits, shift) { \
	300	.type = IIO_VOLTAGE, \
	301	.output = 1, \
	302	.indexed = 1, \
	303	.address = AD5791_ADDR_DAC0, \
	304	.channel = 0, \
	305	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT \| \
	306	IIO_CHAN_INFO_SCALE_SHARED_BIT \| \
	307	IIO_CHAN_INFO_OFFSET_SHARED_BIT, \
	308	.scan_type = IIO_ST('u', bits, 24, shift), \
	309	.ext_info = ad5791_ext_info, \
	310	}
	311
	312	static const struct iio_chan_spec ad5791_channels[] = {
	313	[ID_AD5760] = AD5791_CHAN(16, 4),
	314	[ID_AD5780] = AD5791_CHAN(18, 2),
	315	[ID_AD5781] = AD5791_CHAN(18, 2),
	316	[ID_AD5791] = AD5791_CHAN(20, 0)
	317	};
c5b99396 JC	318
	319	static int ad5791_write_raw(struct iio_dev *indio_dev,
	320	struct iio_chan_spec const *chan,
	321	int val,
	322	int val2,
	323	long mask)
	324	{
	325	struct ad5791_state *st = iio_priv(indio_dev);
	326
	327	switch (mask) {
09f4eb40	328	case IIO_CHAN_INFO_RAW:
021c0a38	329	val &= AD5791_RES_MASK(chan->scan_type.realbits);
c5b99396 JC	330	val <<= chan->scan_type.shift;
	331
	332	return ad5791_spi_write(st->spi, chan->address, val);
	333
	334	default:
	335	return -EINVAL;
	336	}
	337	}
	338
6fe8135f	339	static const struct iio_info ad5791_info = {
c5b99396 JC	340	.read_raw = &ad5791_read_raw,
c5b99396 JC	341	.write_raw = &ad5791_write_raw,
6fe8135f JC	342	.driver_module = THIS_MODULE,
	343	};
	344
fc52692c	345	static int ad5791_probe(struct spi_device *spi)
69d900a6 MH	346	{
69d900a6 MH	347	struct ad5791_platform_data *pdata = spi->dev.platform_data;
f5730d52	348	struct iio_dev *indio_dev;
69d900a6 MH	349	struct ad5791_state *st;
	350	int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;
	351
7cbb7537	352	indio_dev = iio_device_alloc(sizeof(*st));
26a54797 JC	353	if (indio_dev == NULL) {
	354	ret = -ENOMEM;
	355	goto error_ret;
	356	}
	357	st = iio_priv(indio_dev);
	358	st->reg_vdd = regulator_get(&spi->dev, "vdd");
	359	if (!IS_ERR(st->reg_vdd)) {
	360	ret = regulator_enable(st->reg_vdd);
69d900a6 MH	361	if (ret)
	362	goto error_put_reg_pos;
	363
7e2dcc69 AL	364	ret = regulator_get_voltage(st->reg_vdd);
	365	if (ret < 0)
	366	goto error_disable_reg_pos;
	367
	368	pos_voltage_uv = ret;
69d900a6 MH	369	}
69d900a6 MH	370
26a54797 JC	371	st->reg_vss = regulator_get(&spi->dev, "vss");
	372	if (!IS_ERR(st->reg_vss)) {
	373	ret = regulator_enable(st->reg_vss);
69d900a6 MH	374	if (ret)
	375	goto error_put_reg_neg;
	376
7e2dcc69 AL	377	ret = regulator_get_voltage(st->reg_vss);
	378	if (ret < 0)
	379	goto error_disable_reg_neg;
	380
	381	neg_voltage_uv = ret;
69d900a6 MH	382	}
69d900a6 MH	383
f5730d52 JC	384	st->pwr_down = true;
	385	st->spi = spi;
	386
9dc9961d LPC	387	if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {
	388	st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;
	389	st->vref_neg_mv = neg_voltage_uv / 1000;
	390	} else if (pdata) {
	391	st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;
	392	st->vref_neg_mv = pdata->vref_neg_mv;
	393	} else {
69d900a6	394	dev_warn(&spi->dev, "reference voltage unspecified\n");
9dc9961d	395	}
69d900a6 MH	396
	397	ret = ad5791_spi_write(spi, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);
	398	if (ret)
26a54797	399	goto error_disable_reg_neg;
69d900a6	400
c5b99396 JC	401	st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi)
c5b99396 JC	402	->driver_data];
69d900a6 MH	403
69d900a6 MH	404
ba1c2bb2 MH	405	st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))
ba1c2bb2 MH	406	\| ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) \|
69d900a6 MH	407	AD5791_CTRL_BIN2SC;
	408
	409	ret = ad5791_spi_write(spi, AD5791_ADDR_CTRL, st->ctrl \|
	410	AD5791_CTRL_OPGND \| AD5791_CTRL_DACTRI);
	411	if (ret)
26a54797	412	goto error_disable_reg_neg;
69d900a6	413
f5730d52 JC	414	spi_set_drvdata(spi, indio_dev);
	415	indio_dev->dev.parent = &spi->dev;
	416	indio_dev->info = &ad5791_info;
	417	indio_dev->modes = INDIO_DIRECT_MODE;
c5b99396 JC	418	indio_dev->channels
	419	= &ad5791_channels[spi_get_device_id(spi)->driver_data];
	420	indio_dev->num_channels = 1;
	421	indio_dev->name = spi_get_device_id(st->spi)->name;
f5730d52	422	ret = iio_device_register(indio_dev);
69d900a6	423	if (ret)
26a54797	424	goto error_disable_reg_neg;
69d900a6 MH	425
	426	return 0;
	427
69d900a6	428	error_disable_reg_neg:
26a54797 JC	429	if (!IS_ERR(st->reg_vss))
26a54797 JC	430	regulator_disable(st->reg_vss);
69d900a6	431	error_put_reg_neg:
26a54797 JC	432	if (!IS_ERR(st->reg_vss))
26a54797 JC	433	regulator_put(st->reg_vss);
69d900a6	434
7e2dcc69	435	error_disable_reg_pos:
26a54797 JC	436	if (!IS_ERR(st->reg_vdd))
26a54797 JC	437	regulator_disable(st->reg_vdd);
69d900a6	438	error_put_reg_pos:
26a54797 JC	439	if (!IS_ERR(st->reg_vdd))
26a54797 JC	440	regulator_put(st->reg_vdd);
7cbb7537	441	iio_device_free(indio_dev);
26a54797	442	error_ret:
69d900a6	443
69d900a6 MH	444	return ret;
	445	}
	446
fc52692c	447	static int ad5791_remove(struct spi_device *spi)
69d900a6	448	{
f5730d52 JC	449	struct iio_dev *indio_dev = spi_get_drvdata(spi);
f5730d52 JC	450	struct ad5791_state *st = iio_priv(indio_dev);
69d900a6	451
d2fffd6c	452	iio_device_unregister(indio_dev);
69d900a6	453	if (!IS_ERR(st->reg_vdd)) {
26a54797 JC	454	regulator_disable(st->reg_vdd);
26a54797 JC	455	regulator_put(st->reg_vdd);
69d900a6 MH	456	}
	457
	458	if (!IS_ERR(st->reg_vss)) {
26a54797 JC	459	regulator_disable(st->reg_vss);
26a54797 JC	460	regulator_put(st->reg_vss);
69d900a6	461	}
7cbb7537	462	iio_device_free(indio_dev);
26d25ae3	463
69d900a6 MH	464	return 0;
	465	}
	466
	467	static const struct spi_device_id ad5791_id[] = {
ba1c2bb2 MH	468	{"ad5760", ID_AD5760},
ba1c2bb2 MH	469	{"ad5780", ID_AD5780},
69d900a6	470	{"ad5781", ID_AD5781},
9d41c5bb	471	{"ad5790", ID_AD5791},
ba1c2bb2	472	{"ad5791", ID_AD5791},
69d900a6 MH	473	{}
69d900a6 MH	474	};
55e4390c	475	MODULE_DEVICE_TABLE(spi, ad5791_id);
69d900a6 MH	476
	477	static struct spi_driver ad5791_driver = {
	478	.driver = {
	479	.name = "ad5791",
	480	.owner = THIS_MODULE,
	481	},
	482	.probe = ad5791_probe,
fc52692c	483	.remove = ad5791_remove,
69d900a6 MH	484	.id_table = ad5791_id,
69d900a6 MH	485	};
ae6ae6fe	486	module_spi_driver(ad5791_driver);
69d900a6 MH	487
69d900a6 MH	488	MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
9d41c5bb	489	MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC");
69d900a6	490	MODULE_LICENSE("GPL v2");