[mirror_ubuntu-hirsute-kernel.git] / drivers / iio / dac / mcp4725.c

/*
 * mcp4725.c - Support for Microchip MCP4725/6
 *
 * Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * Based on max517 by Roland Stigge <stigge@antcom.de>
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file COPYING in the main
 * directory of this archive for more details.
 *
 * driver for the Microchip I2C 12-bit digital-to-analog converter (DAC)
 * (7-bit I2C slave address 0x60, the three LSBs can be configured in
 * hardware)
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/regulator/consumer.h>
#include <linux/of_device.h>
#include <linux/of.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#include <linux/iio/dac/mcp4725.h>

#define MCP4725_DRV_NAME "mcp4725"

#define MCP472X_REF_VDD			0x00
#define MCP472X_REF_VREF_UNBUFFERED	0x02
#define MCP472X_REF_VREF_BUFFERED	0x03

struct mcp4725_data {
	struct i2c_client *client;
	int id;
	unsigned ref_mode;
	bool vref_buffered;
	u16 dac_value;
	bool powerdown;
	unsigned powerdown_mode;
	struct regulator *vdd_reg;
	struct regulator *vref_reg;
};

static int __maybe_unused mcp4725_suspend(struct device *dev)
{
	struct mcp4725_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	u8 outbuf[2];

	outbuf[0] = (data->powerdown_mode + 1) << 4;
	outbuf[1] = 0;
	data->powerdown = true;

	return i2c_master_send(data->client, outbuf, 2);
}

static int __maybe_unused mcp4725_resume(struct device *dev)
{
	struct mcp4725_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	u8 outbuf[2];

	/* restore previous DAC value */
	outbuf[0] = (data->dac_value >> 8) & 0xf;
	outbuf[1] = data->dac_value & 0xff;
	data->powerdown = false;

	return i2c_master_send(data->client, outbuf, 2);
}
static SIMPLE_DEV_PM_OPS(mcp4725_pm_ops, mcp4725_suspend, mcp4725_resume);

static ssize_t mcp4725_store_eeprom(struct device *dev,
	struct device_attribute *attr, const char *buf, size_t len)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct mcp4725_data *data = iio_priv(indio_dev);
	int tries = 20;
	u8 inoutbuf[3];
	bool state;
	int ret;

	ret = strtobool(buf, &state);
	if (ret < 0)
		return ret;

	if (!state)
		return 0;

	inoutbuf[0] = 0x60; /* write EEPROM */
	inoutbuf[0] |= data->ref_mode << 3;
	inoutbuf[0] |= data->powerdown ? ((data->powerdown_mode + 1) << 1) : 0;
	inoutbuf[1] = data->dac_value >> 4;
	inoutbuf[2] = (data->dac_value & 0xf) << 4;

	ret = i2c_master_send(data->client, inoutbuf, 3);
	if (ret < 0)
		return ret;
	else if (ret != 3)
		return -EIO;

	/* wait for write complete, takes up to 50ms */
	while (tries--) {
		msleep(20);
		ret = i2c_master_recv(data->client, inoutbuf, 3);
		if (ret < 0)
			return ret;
		else if (ret != 3)
			return -EIO;

		if (inoutbuf[0] & 0x80)
			break;
	}

	if (tries < 0) {
		dev_err(&data->client->dev,
			"mcp4725_store_eeprom() failed, incomplete\n");
		return -EIO;
	}

	return len;
}

static IIO_DEVICE_ATTR(store_eeprom, S_IWUSR, NULL, mcp4725_store_eeprom, 0);

static struct attribute *mcp4725_attributes[] = {
	&iio_dev_attr_store_eeprom.dev_attr.attr,
	NULL,
};

static const struct attribute_group mcp4725_attribute_group = {
	.attrs = mcp4725_attributes,
};

static const char * const mcp4725_powerdown_modes[] = {
	"1kohm_to_gnd",
	"100kohm_to_gnd",
	"500kohm_to_gnd"
};

static const char * const mcp4726_powerdown_modes[] = {
	"1kohm_to_gnd",
	"125kohm_to_gnd",
	"640kohm_to_gnd"
};

static int mcp4725_get_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan)
{
	struct mcp4725_data *data = iio_priv(indio_dev);

	return data->powerdown_mode;
}

static int mcp4725_set_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, unsigned mode)
{
	struct mcp4725_data *data = iio_priv(indio_dev);

	data->powerdown_mode = mode;

	return 0;
}

static ssize_t mcp4725_read_powerdown(struct iio_dev *indio_dev,
	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
	struct mcp4725_data *data = iio_priv(indio_dev);

	return sprintf(buf, "%d\n", data->powerdown);
}

static ssize_t mcp4725_write_powerdown(struct iio_dev *indio_dev,
	 uintptr_t private, const struct iio_chan_spec *chan,
	 const char *buf, size_t len)
{
	struct mcp4725_data *data = iio_priv(indio_dev);
	bool state;
	int ret;

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

	if (state)
		ret = mcp4725_suspend(&data->client->dev);
	else
		ret = mcp4725_resume(&data->client->dev);
	if (ret < 0)
		return ret;

	return len;
}

enum chip_id {
	MCP4725,
	MCP4726,
};

static const struct iio_enum mcp472x_powerdown_mode_enum[] = {
	[MCP4725] = {
		.items = mcp4725_powerdown_modes,
		.num_items = ARRAY_SIZE(mcp4725_powerdown_modes),
		.get = mcp4725_get_powerdown_mode,
		.set = mcp4725_set_powerdown_mode,
	},
	[MCP4726] = {
		.items = mcp4726_powerdown_modes,
		.num_items = ARRAY_SIZE(mcp4726_powerdown_modes),
		.get = mcp4725_get_powerdown_mode,
		.set = mcp4725_set_powerdown_mode,
	},
};

static const struct iio_chan_spec_ext_info mcp4725_ext_info[] = {
	{
		.name = "powerdown",
		.read = mcp4725_read_powerdown,
		.write = mcp4725_write_powerdown,
		.shared = IIO_SEPARATE,
	},
	IIO_ENUM("powerdown_mode", IIO_SEPARATE,
			&mcp472x_powerdown_mode_enum[MCP4725]),
	IIO_ENUM_AVAILABLE("powerdown_mode",
			&mcp472x_powerdown_mode_enum[MCP4725]),
	{ },
};

static const struct iio_chan_spec_ext_info mcp4726_ext_info[] = {
	{
		.name = "powerdown",
		.read = mcp4725_read_powerdown,
		.write = mcp4725_write_powerdown,
		.shared = IIO_SEPARATE,
	},
	IIO_ENUM("powerdown_mode", IIO_SEPARATE,
			&mcp472x_powerdown_mode_enum[MCP4726]),
	IIO_ENUM_AVAILABLE("powerdown_mode",
			&mcp472x_powerdown_mode_enum[MCP4726]),
	{ },
};

static const struct iio_chan_spec mcp472x_channel[] = {
	[MCP4725] = {
		.type		= IIO_VOLTAGE,
		.indexed	= 1,
		.output		= 1,
		.channel	= 0,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
		.ext_info	= mcp4725_ext_info,
	},
	[MCP4726] = {
		.type		= IIO_VOLTAGE,
		.indexed	= 1,
		.output		= 1,
		.channel	= 0,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
		.ext_info	= mcp4726_ext_info,
	},
};

static int mcp4725_set_value(struct iio_dev *indio_dev, int val)
{
	struct mcp4725_data *data = iio_priv(indio_dev);
	u8 outbuf[2];
	int ret;

	if (val >= (1 << 12) || val < 0)
		return -EINVAL;

	outbuf[0] = (val >> 8) & 0xf;
	outbuf[1] = val & 0xff;

	ret = i2c_master_send(data->client, outbuf, 2);
	if (ret < 0)
		return ret;
	else if (ret != 2)
		return -EIO;
	else
		return 0;
}

static int mcp4726_set_cfg(struct iio_dev *indio_dev)
{
	struct mcp4725_data *data = iio_priv(indio_dev);
	u8 outbuf[3];
	int ret;

	outbuf[0] = 0x40;
	outbuf[0] |= data->ref_mode << 3;
	if (data->powerdown)
		outbuf[0] |= data->powerdown << 1;
	outbuf[1] = data->dac_value >> 4;
	outbuf[2] = (data->dac_value & 0xf) << 4;

	ret = i2c_master_send(data->client, outbuf, 3);
	if (ret < 0)
		return ret;
	else if (ret != 3)
		return -EIO;
	else
		return 0;
}

static int mcp4725_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long mask)
{
	struct mcp4725_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		*val = data->dac_value;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		if (data->ref_mode == MCP472X_REF_VDD)
			ret = regulator_get_voltage(data->vdd_reg);
		else
			ret = regulator_get_voltage(data->vref_reg);

		if (ret < 0)
			return ret;

		*val = ret / 1000;
		*val2 = 12;
		return IIO_VAL_FRACTIONAL_LOG2;
	}
	return -EINVAL;
}

static int mcp4725_write_raw(struct iio_dev *indio_dev,
			       struct iio_chan_spec const *chan,
			       int val, int val2, long mask)
{
	struct mcp4725_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = mcp4725_set_value(indio_dev, val);
		data->dac_value = val;
		break;
	default:
		ret = -EINVAL;
		break;
	}

	return ret;
}

static const struct iio_info mcp4725_info = {
	.read_raw = mcp4725_read_raw,
	.write_raw = mcp4725_write_raw,
	.attrs = &mcp4725_attribute_group,
};

#ifdef CONFIG_OF
static int mcp4725_probe_dt(struct device *dev,
			    struct mcp4725_platform_data *pdata)
{
	struct device_node *np = dev->of_node;

	if (!np)
		return -ENODEV;

	/* check if is the vref-supply defined */
	pdata->use_vref = of_property_read_bool(np, "vref-supply");
	pdata->vref_buffered =
		of_property_read_bool(np, "microchip,vref-buffered");

	return 0;
}
#else
static int mcp4725_probe_dt(struct device *dev,
			    struct mcp4725_platform_data *platform_data)
{
	return -ENODEV;
}
#endif

static int mcp4725_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct mcp4725_data *data;
	struct iio_dev *indio_dev;
	struct mcp4725_platform_data *pdata, pdata_dt;
	u8 inbuf[4];
	u8 pd;
	u8 ref;
	int err;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (indio_dev == NULL)
		return -ENOMEM;
	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	if (client->dev.of_node)
		data->id = (enum chip_id)of_device_get_match_data(&client->dev);
	else
		data->id = id->driver_data;
	pdata = dev_get_platdata(&client->dev);

	if (!pdata) {
		err = mcp4725_probe_dt(&client->dev, &pdata_dt);
		if (err) {
			dev_err(&client->dev,
				"invalid platform or devicetree data");
			return err;
		}
		pdata = &pdata_dt;
	}

	if (data->id == MCP4725 && pdata->use_vref) {
		dev_err(&client->dev,
			"external reference is unavailable on MCP4725");
		return -EINVAL;
	}

	if (!pdata->use_vref && pdata->vref_buffered) {
		dev_err(&client->dev,
			"buffering is unavailable on the internal reference");
		return -EINVAL;
	}

	if (!pdata->use_vref)
		data->ref_mode = MCP472X_REF_VDD;
	else
		data->ref_mode = pdata->vref_buffered ?
			MCP472X_REF_VREF_BUFFERED :
			MCP472X_REF_VREF_UNBUFFERED;

	data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
	if (IS_ERR(data->vdd_reg))
		return PTR_ERR(data->vdd_reg);

	err = regulator_enable(data->vdd_reg);
	if (err)
		return err;

	if (pdata->use_vref) {
		data->vref_reg = devm_regulator_get(&client->dev, "vref");
		if (IS_ERR(data->vref_reg)) {
			err = PTR_ERR(data->vref_reg);
			goto err_disable_vdd_reg;
		}

		err = regulator_enable(data->vref_reg);
		if (err)
			goto err_disable_vdd_reg;
	}

	indio_dev->dev.parent = &client->dev;
	indio_dev->name = id->name;
	indio_dev->info = &mcp4725_info;
	indio_dev->channels = &mcp472x_channel[id->driver_data];
	indio_dev->num_channels = 1;
	indio_dev->modes = INDIO_DIRECT_MODE;

	/* read current DAC value and settings */
	err = i2c_master_recv(client, inbuf, data->id == MCP4725 ? 3 : 4);

	if (err < 0) {
		dev_err(&client->dev, "failed to read DAC value");
		goto err_disable_vref_reg;
	}
	pd = (inbuf[0] >> 1) & 0x3;
	data->powerdown = pd > 0;
	data->powerdown_mode = pd ? pd - 1 : 2; /* largest resistor to gnd */
	data->dac_value = (inbuf[1] << 4) | (inbuf[2] >> 4);
	if (data->id == MCP4726)
		ref = (inbuf[3] >> 3) & 0x3;

	if (data->id == MCP4726 && ref != data->ref_mode) {
		dev_info(&client->dev,
			"voltage reference mode differs (conf: %u, eeprom: %u), setting %u",
			data->ref_mode, ref, data->ref_mode);
		err = mcp4726_set_cfg(indio_dev);
		if (err < 0)
			goto err_disable_vref_reg;
	}
 
	err = iio_device_register(indio_dev);
	if (err)
		goto err_disable_vref_reg;

	return 0;

err_disable_vref_reg:
	if (data->vref_reg)
		regulator_disable(data->vref_reg);

err_disable_vdd_reg:
	regulator_disable(data->vdd_reg);

	return err;
}

static int mcp4725_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct mcp4725_data *data = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);

	if (data->vref_reg)
		regulator_disable(data->vref_reg);
	regulator_disable(data->vdd_reg);

	return 0;
}

static const struct i2c_device_id mcp4725_id[] = {
	{ "mcp4725", MCP4725 },
	{ "mcp4726", MCP4726 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mcp4725_id);

#ifdef CONFIG_OF
static const struct of_device_id mcp4725_of_match[] = {
	{
		.compatible = "microchip,mcp4725",
		.data = (void *)MCP4725
	},
	{
		.compatible = "microchip,mcp4726",
		.data = (void *)MCP4726
	},
	{ }
};
MODULE_DEVICE_TABLE(of, mcp4725_of_match);
#endif

static struct i2c_driver mcp4725_driver = {
	.driver = {
		.name	= MCP4725_DRV_NAME,
		.of_match_table = of_match_ptr(mcp4725_of_match),
		.pm	= &mcp4725_pm_ops,
	},
	.probe		= mcp4725_probe,
	.remove		= mcp4725_remove,
	.id_table	= mcp4725_id,
};
module_i2c_driver(mcp4725_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("MCP4725/6 12-bit DAC");
MODULE_LICENSE("GPL");
Commit	Line	Data
cf35ad61	1	/*
35f73967	2	* mcp4725.c - Support for Microchip MCP4725/6
cf35ad61 PM	3	*
	4	* Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
	5	*
	6	* Based on max517 by Roland Stigge <stigge@antcom.de>
	7	*
	8	* This file is subject to the terms and conditions of version 2 of
	9	* the GNU General Public License. See the file COPYING in the main
	10	* directory of this archive for more details.
	11	*
	12	* driver for the Microchip I2C 12-bit digital-to-analog converter (DAC)
	13	* (7-bit I2C slave address 0x60, the three LSBs can be configured in
	14	* hardware)
cf35ad61 PM	15	*/
	16
	17	#include <linux/module.h>
cf35ad61 PM	18	#include <linux/i2c.h>
cf35ad61 PM	19	#include <linux/err.h>
f17b77d6	20	#include <linux/delay.h>
b440f1d9	21	#include <linux/regulator/consumer.h>
8414af1e	22	#include <linux/of_device.h>
88e39a88	23	#include <linux/of.h>
cf35ad61 PM	24
	25	#include <linux/iio/iio.h>
	26	#include <linux/iio/sysfs.h>
	27
	28	#include <linux/iio/dac/mcp4725.h>
	29
	30	#define MCP4725_DRV_NAME "mcp4725"
	31
29157c6d TN	32	#define MCP472X_REF_VDD 0x00
	33	#define MCP472X_REF_VREF_UNBUFFERED 0x02
	34	#define MCP472X_REF_VREF_BUFFERED 0x03
	35
cf35ad61 PM	36	struct mcp4725_data {
cf35ad61 PM	37	struct i2c_client *client;
29157c6d TN	38	int id;
	39	unsigned ref_mode;
	40	bool vref_buffered;
cf35ad61	41	u16 dac_value;
155f1b41 PM	42	bool powerdown;
155f1b41 PM	43	unsigned powerdown_mode;
b440f1d9	44	struct regulator *vdd_reg;
29157c6d	45	struct regulator *vref_reg;
cf35ad61 PM	46	};
cf35ad61 PM	47
1a5bc41a	48	static int __maybe_unused mcp4725_suspend(struct device *dev)
cf35ad61	49	{
a97dd069 PM	50	struct mcp4725_data *data = iio_priv(i2c_get_clientdata(
a97dd069 PM	51	to_i2c_client(dev)));
cf35ad61 PM	52	u8 outbuf[2];
cf35ad61 PM	53
155f1b41	54	outbuf[0] = (data->powerdown_mode + 1) << 4;
cf35ad61	55	outbuf[1] = 0;
155f1b41	56	data->powerdown = true;
cf35ad61	57
a97dd069	58	return i2c_master_send(data->client, outbuf, 2);
cf35ad61 PM	59	}
cf35ad61 PM	60
1a5bc41a	61	static int __maybe_unused mcp4725_resume(struct device *dev)
cf35ad61	62	{
a97dd069 PM	63	struct mcp4725_data *data = iio_priv(i2c_get_clientdata(
a97dd069 PM	64	to_i2c_client(dev)));
cf35ad61 PM	65	u8 outbuf[2];
	66
	67	/* restore previous DAC value */
	68	outbuf[0] = (data->dac_value >> 8) & 0xf;
	69	outbuf[1] = data->dac_value & 0xff;
155f1b41	70	data->powerdown = false;
cf35ad61	71
a97dd069	72	return i2c_master_send(data->client, outbuf, 2);
cf35ad61	73	}
cf35ad61	74	static SIMPLE_DEV_PM_OPS(mcp4725_pm_ops, mcp4725_suspend, mcp4725_resume);
cf35ad61	75
4fd313da	76	static ssize_t mcp4725_store_eeprom(struct device *dev,
f17b77d6 PM	77	struct device_attribute attr, const char buf, size_t len)
	78	{
	79	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	80	struct mcp4725_data *data = iio_priv(indio_dev);
	81	int tries = 20;
	82	u8 inoutbuf[3];
	83	bool state;
	84	int ret;
	85
	86	ret = strtobool(buf, &state);
	87	if (ret < 0)
	88	return ret;
	89
	90	if (!state)
	91	return 0;
	92
	93	inoutbuf[0] = 0x60; /* write EEPROM */
29157c6d	94	inoutbuf[0] \|= data->ref_mode << 3;
06003531	95	inoutbuf[0] \|= data->powerdown ? ((data->powerdown_mode + 1) << 1) : 0;
f17b77d6 PM	96	inoutbuf[1] = data->dac_value >> 4;
	97	inoutbuf[2] = (data->dac_value & 0xf) << 4;
	98
	99	ret = i2c_master_send(data->client, inoutbuf, 3);
	100	if (ret < 0)
	101	return ret;
	102	else if (ret != 3)
	103	return -EIO;
	104
	105	/* wait for write complete, takes up to 50ms */
	106	while (tries--) {
	107	msleep(20);
	108	ret = i2c_master_recv(data->client, inoutbuf, 3);
	109	if (ret < 0)
	110	return ret;
	111	else if (ret != 3)
	112	return -EIO;
	113
	114	if (inoutbuf[0] & 0x80)
	115	break;
	116	}
	117
	118	if (tries < 0) {
	119	dev_err(&data->client->dev,
	120	"mcp4725_store_eeprom() failed, incomplete\n");
	121	return -EIO;
	122	}
	123
	124	return len;
	125	}
	126
	127	static IIO_DEVICE_ATTR(store_eeprom, S_IWUSR, NULL, mcp4725_store_eeprom, 0);
	128
	129	static struct attribute *mcp4725_attributes[] = {
	130	&iio_dev_attr_store_eeprom.dev_attr.attr,
	131	NULL,
	132	};
	133
	134	static const struct attribute_group mcp4725_attribute_group = {
	135	.attrs = mcp4725_attributes,
	136	};
	137
155f1b41 PM	138	static const char * const mcp4725_powerdown_modes[] = {
	139	"1kohm_to_gnd",
	140	"100kohm_to_gnd",
	141	"500kohm_to_gnd"
	142	};
	143
35f73967 AM	144	static const char * const mcp4726_powerdown_modes[] = {
	145	"1kohm_to_gnd",
	146	"125kohm_to_gnd",
	147	"640kohm_to_gnd"
	148	};
	149
155f1b41 PM	150	static int mcp4725_get_powerdown_mode(struct iio_dev *indio_dev,
	151	const struct iio_chan_spec *chan)
	152	{
	153	struct mcp4725_data *data = iio_priv(indio_dev);
	154
	155	return data->powerdown_mode;
	156	}
	157
	158	static int mcp4725_set_powerdown_mode(struct iio_dev *indio_dev,
	159	const struct iio_chan_spec *chan, unsigned mode)
	160	{
	161	struct mcp4725_data *data = iio_priv(indio_dev);
	162
	163	data->powerdown_mode = mode;
	164
	165	return 0;
	166	}
	167
	168	static ssize_t mcp4725_read_powerdown(struct iio_dev *indio_dev,
	169	uintptr_t private, const struct iio_chan_spec chan, char buf)
	170	{
	171	struct mcp4725_data *data = iio_priv(indio_dev);
	172
	173	return sprintf(buf, "%d\n", data->powerdown);
	174	}
	175
	176	static ssize_t mcp4725_write_powerdown(struct iio_dev *indio_dev,
	177	uintptr_t private, const struct iio_chan_spec *chan,
	178	const char *buf, size_t len)
	179	{
	180	struct mcp4725_data *data = iio_priv(indio_dev);
	181	bool state;
	182	int ret;
	183
	184	ret = strtobool(buf, &state);
	185	if (ret)
	186	return ret;
	187
	188	if (state)
	189	ret = mcp4725_suspend(&data->client->dev);
	190	else
	191	ret = mcp4725_resume(&data->client->dev);
	192	if (ret < 0)
	193	return ret;
	194
	195	return len;
	196	}
	197
8414af1e	198	enum chip_id {
35f73967 AM	199	MCP4725,
	200	MCP4726,
	201	};
	202
	203	static const struct iio_enum mcp472x_powerdown_mode_enum[] = {
	204	[MCP4725] = {
	205	.items = mcp4725_powerdown_modes,
	206	.num_items = ARRAY_SIZE(mcp4725_powerdown_modes),
	207	.get = mcp4725_get_powerdown_mode,
	208	.set = mcp4725_set_powerdown_mode,
	209	},
	210	[MCP4726] = {
	211	.items = mcp4726_powerdown_modes,
	212	.num_items = ARRAY_SIZE(mcp4726_powerdown_modes),
	213	.get = mcp4725_get_powerdown_mode,
	214	.set = mcp4725_set_powerdown_mode,
	215	},
155f1b41 PM	216	};
	217
	218	static const struct iio_chan_spec_ext_info mcp4725_ext_info[] = {
	219	{
	220	.name = "powerdown",
	221	.read = mcp4725_read_powerdown,
	222	.write = mcp4725_write_powerdown,
3704432f	223	.shared = IIO_SEPARATE,
155f1b41	224	},
35f73967 AM	225	IIO_ENUM("powerdown_mode", IIO_SEPARATE,
	226	&mcp472x_powerdown_mode_enum[MCP4725]),
	227	IIO_ENUM_AVAILABLE("powerdown_mode",
	228	&mcp472x_powerdown_mode_enum[MCP4725]),
	229	{ },
	230	};
	231
	232	static const struct iio_chan_spec_ext_info mcp4726_ext_info[] = {
	233	{
	234	.name = "powerdown",
	235	.read = mcp4725_read_powerdown,
	236	.write = mcp4725_write_powerdown,
	237	.shared = IIO_SEPARATE,
	238	},
	239	IIO_ENUM("powerdown_mode", IIO_SEPARATE,
	240	&mcp472x_powerdown_mode_enum[MCP4726]),
	241	IIO_ENUM_AVAILABLE("powerdown_mode",
	242	&mcp472x_powerdown_mode_enum[MCP4726]),
155f1b41 PM	243	{ },
	244	};
	245
35f73967 AM	246	static const struct iio_chan_spec mcp472x_channel[] = {
	247	[MCP4725] = {
	248	.type = IIO_VOLTAGE,
	249	.indexed = 1,
	250	.output = 1,
	251	.channel = 0,
	252	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	253	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
	254	.ext_info = mcp4725_ext_info,
	255	},
	256	[MCP4726] = {
	257	.type = IIO_VOLTAGE,
	258	.indexed = 1,
	259	.output = 1,
	260	.channel = 0,
	261	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	262	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
	263	.ext_info = mcp4726_ext_info,
	264	},
cf35ad61 PM	265	};
	266
	267	static int mcp4725_set_value(struct iio_dev *indio_dev, int val)
	268	{
	269	struct mcp4725_data *data = iio_priv(indio_dev);
	270	u8 outbuf[2];
	271	int ret;
	272
	273	if (val >= (1 << 12) \|\| val < 0)
	274	return -EINVAL;
	275
	276	outbuf[0] = (val >> 8) & 0xf;
	277	outbuf[1] = val & 0xff;
	278
	279	ret = i2c_master_send(data->client, outbuf, 2);
	280	if (ret < 0)
	281	return ret;
	282	else if (ret != 2)
	283	return -EIO;
	284	else
	285	return 0;
	286	}
	287
29157c6d TN	288	static int mcp4726_set_cfg(struct iio_dev *indio_dev)
	289	{
	290	struct mcp4725_data *data = iio_priv(indio_dev);
	291	u8 outbuf[3];
	292	int ret;
	293
	294	outbuf[0] = 0x40;
	295	outbuf[0] \|= data->ref_mode << 3;
	296	if (data->powerdown)
	297	outbuf[0] \|= data->powerdown << 1;
	298	outbuf[1] = data->dac_value >> 4;
	299	outbuf[2] = (data->dac_value & 0xf) << 4;
	300
	301	ret = i2c_master_send(data->client, outbuf, 3);
	302	if (ret < 0)
	303	return ret;
	304	else if (ret != 3)
	305	return -EIO;
	306	else
	307	return 0;
	308	}
	309
cf35ad61 PM	310	static int mcp4725_read_raw(struct iio_dev *indio_dev,
	311	struct iio_chan_spec const *chan,
	312	int val, int val2, long mask)
	313	{
	314	struct mcp4725_data *data = iio_priv(indio_dev);
b440f1d9	315	int ret;
cf35ad61 PM	316
	317	switch (mask) {
	318	case IIO_CHAN_INFO_RAW:
	319	*val = data->dac_value;
	320	return IIO_VAL_INT;
	321	case IIO_CHAN_INFO_SCALE:
29157c6d TN	322	if (data->ref_mode == MCP472X_REF_VDD)
	323	ret = regulator_get_voltage(data->vdd_reg);
	324	else
	325	ret = regulator_get_voltage(data->vref_reg);
	326
b440f1d9 TN	327	if (ret < 0)
	328	return ret;
	329
	330	*val = ret / 1000;
b117f96f LPC	331	*val2 = 12;
b117f96f LPC	332	return IIO_VAL_FRACTIONAL_LOG2;
cf35ad61 PM	333	}
	334	return -EINVAL;
	335	}
	336
	337	static int mcp4725_write_raw(struct iio_dev *indio_dev,
	338	struct iio_chan_spec const *chan,
	339	int val, int val2, long mask)
	340	{
	341	struct mcp4725_data *data = iio_priv(indio_dev);
	342	int ret;
	343
	344	switch (mask) {
	345	case IIO_CHAN_INFO_RAW:
	346	ret = mcp4725_set_value(indio_dev, val);
	347	data->dac_value = val;
	348	break;
	349	default:
	350	ret = -EINVAL;
	351	break;
	352	}
	353
	354	return ret;
	355	}
	356
	357	static const struct iio_info mcp4725_info = {
	358	.read_raw = mcp4725_read_raw,
	359	.write_raw = mcp4725_write_raw,
f17b77d6	360	.attrs = &mcp4725_attribute_group,
cf35ad61 PM	361	};
cf35ad61 PM	362
88e39a88 TN	363	#ifdef CONFIG_OF
	364	static int mcp4725_probe_dt(struct device *dev,
	365	struct mcp4725_platform_data *pdata)
	366	{
	367	struct device_node *np = dev->of_node;
	368
	369	if (!np)
	370	return -ENODEV;
	371
	372	/* check if is the vref-supply defined */
	373	pdata->use_vref = of_property_read_bool(np, "vref-supply");
	374	pdata->vref_buffered =
	375	of_property_read_bool(np, "microchip,vref-buffered");
	376
	377	return 0;
	378	}
	379	#else
	380	static int mcp4725_probe_dt(struct device *dev,
	381	struct mcp4725_platform_data *platform_data)
	382	{
	383	return -ENODEV;
	384	}
	385	#endif
	386
fc52692c GKH	387	static int mcp4725_probe(struct i2c_client *client,
fc52692c GKH	388	const struct i2c_device_id *id)
cf35ad61 PM	389	{
	390	struct mcp4725_data *data;
	391	struct iio_dev *indio_dev;
88e39a88	392	struct mcp4725_platform_data *pdata, pdata_dt;
29157c6d	393	u8 inbuf[4];
155f1b41	394	u8 pd;
29157c6d	395	u8 ref;
cf35ad61 PM	396	int err;
cf35ad61 PM	397
b6ff86f3 PM	398	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	399	if (indio_dev == NULL)
	400	return -ENOMEM;
cf35ad61 PM	401	data = iio_priv(indio_dev);
	402	i2c_set_clientdata(client, indio_dev);
	403	data->client = client;
8414af1e JMC	404	if (client->dev.of_node)
	405	data->id = (enum chip_id)of_device_get_match_data(&client->dev);
	406	else
	407	data->id = id->driver_data;
88e39a88 TN	408	pdata = dev_get_platdata(&client->dev);
	409
	410	if (!pdata) {
	411	err = mcp4725_probe_dt(&client->dev, &pdata_dt);
	412	if (err) {
	413	dev_err(&client->dev,
	414	"invalid platform or devicetree data");
	415	return err;
	416	}
	417	pdata = &pdata_dt;
	418	}
29157c6d TN	419
	420	if (data->id == MCP4725 && pdata->use_vref) {
	421	dev_err(&client->dev,
	422	"external reference is unavailable on MCP4725");
	423	return -EINVAL;
	424	}
	425
	426	if (!pdata->use_vref && pdata->vref_buffered) {
	427	dev_err(&client->dev,
	428	"buffering is unavailable on the internal reference");
	429	return -EINVAL;
	430	}
	431
	432	if (!pdata->use_vref)
	433	data->ref_mode = MCP472X_REF_VDD;
	434	else
	435	data->ref_mode = pdata->vref_buffered ?
	436	MCP472X_REF_VREF_BUFFERED :
	437	MCP472X_REF_VREF_UNBUFFERED;
cf35ad61	438
b440f1d9 TN	439	data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
	440	if (IS_ERR(data->vdd_reg))
	441	return PTR_ERR(data->vdd_reg);
	442
	443	err = regulator_enable(data->vdd_reg);
	444	if (err)
	445	return err;
	446
29157c6d TN	447	if (pdata->use_vref) {
	448	data->vref_reg = devm_regulator_get(&client->dev, "vref");
	449	if (IS_ERR(data->vref_reg)) {
30df2d18	450	err = PTR_ERR(data->vref_reg);
29157c6d TN	451	goto err_disable_vdd_reg;
	452	}
	453
	454	err = regulator_enable(data->vref_reg);
	455	if (err)
	456	goto err_disable_vdd_reg;
	457	}
	458
cf35ad61	459	indio_dev->dev.parent = &client->dev;
97a249e9	460	indio_dev->name = id->name;
cf35ad61	461	indio_dev->info = &mcp4725_info;
35f73967	462	indio_dev->channels = &mcp472x_channel[id->driver_data];
cf35ad61 PM	463	indio_dev->num_channels = 1;
	464	indio_dev->modes = INDIO_DIRECT_MODE;
	465
29157c6d TN	466	/* read current DAC value and settings */
	467	err = i2c_master_recv(client, inbuf, data->id == MCP4725 ? 3 : 4);
	468
cf35ad61 PM	469	if (err < 0) {
cf35ad61 PM	470	dev_err(&client->dev, "failed to read DAC value");
29157c6d	471	goto err_disable_vref_reg;
cf35ad61	472	}
155f1b41	473	pd = (inbuf[0] >> 1) & 0x3;
f272f19c	474	data->powerdown = pd > 0;
6a31c225	475	data->powerdown_mode = pd ? pd - 1 : 2; /* largest resistor to gnd */
cf35ad61	476	data->dac_value = (inbuf[1] << 4) \| (inbuf[2] >> 4);
29157c6d TN	477	if (data->id == MCP4726)
	478	ref = (inbuf[3] >> 3) & 0x3;
	479
	480	if (data->id == MCP4726 && ref != data->ref_mode) {
	481	dev_info(&client->dev,
	482	"voltage reference mode differs (conf: %u, eeprom: %u), setting %u",
	483	data->ref_mode, ref, data->ref_mode);
	484	err = mcp4726_set_cfg(indio_dev);
	485	if (err < 0)
	486	goto err_disable_vref_reg;
	487	}
	488
b440f1d9 TN	489	err = iio_device_register(indio_dev);
b440f1d9 TN	490	if (err)
29157c6d	491	goto err_disable_vref_reg;
b440f1d9 TN	492
	493	return 0;
	494
29157c6d TN	495	err_disable_vref_reg:
	496	if (data->vref_reg)
	497	regulator_disable(data->vref_reg);
b440f1d9 TN	498
	499	err_disable_vdd_reg:
	500	regulator_disable(data->vdd_reg);
	501
	502	return err;
cf35ad61 PM	503	}
cf35ad61 PM	504
fc52692c	505	static int mcp4725_remove(struct i2c_client *client)
cf35ad61	506	{
b440f1d9 TN	507	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	508	struct mcp4725_data *data = iio_priv(indio_dev);
	509
	510	iio_device_unregister(indio_dev);
	511
29157c6d TN	512	if (data->vref_reg)
29157c6d TN	513	regulator_disable(data->vref_reg);
b440f1d9 TN	514	regulator_disable(data->vdd_reg);
b440f1d9 TN	515
cf35ad61 PM	516	return 0;
	517	}
	518
	519	static const struct i2c_device_id mcp4725_id[] = {
35f73967 AM	520	{ "mcp4725", MCP4725 },
35f73967 AM	521	{ "mcp4726", MCP4726 },
cf35ad61 PM	522	{ }
	523	};
	524	MODULE_DEVICE_TABLE(i2c, mcp4725_id);
	525
8414af1e JMC	526	#ifdef CONFIG_OF
	527	static const struct of_device_id mcp4725_of_match[] = {
	528	{
	529	.compatible = "microchip,mcp4725",
	530	.data = (void *)MCP4725
	531	},
	532	{
	533	.compatible = "microchip,mcp4726",
	534	.data = (void *)MCP4726
	535	},
	536	{ }
	537	};
	538	MODULE_DEVICE_TABLE(of, mcp4725_of_match);
	539	#endif
	540
cf35ad61 PM	541	static struct i2c_driver mcp4725_driver = {
	542	.driver = {
	543	.name = MCP4725_DRV_NAME,
8414af1e	544	.of_match_table = of_match_ptr(mcp4725_of_match),
1a5bc41a	545	.pm = &mcp4725_pm_ops,
cf35ad61 PM	546	},
cf35ad61 PM	547	.probe = mcp4725_probe,
fc52692c	548	.remove = mcp4725_remove,
cf35ad61 PM	549	.id_table = mcp4725_id,
	550	};
	551	module_i2c_driver(mcp4725_driver);
	552
	553	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
35f73967	554	MODULE_DESCRIPTION("MCP4725/6 12-bit DAC");
cf35ad61	555	MODULE_LICENSE("GPL");