[deliverable/linux.git] / drivers / iio / adc / ti-adc081c.c

/*
 * TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver
 *
 * Copyright (C) 2012 Avionic Design GmbH
 * Copyright (C) 2016 Intel
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Datasheets:
 *	http://www.ti.com/lit/ds/symlink/adc081c021.pdf
 *	http://www.ti.com/lit/ds/symlink/adc101c021.pdf
 *	http://www.ti.com/lit/ds/symlink/adc121c021.pdf
 *
 * The devices have a very similar interface and differ mostly in the number of
 * bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2
 * bits of value registers are reserved.
 */

#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>

#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/regulator/consumer.h>

struct adc081c {
	struct i2c_client *i2c;
	struct regulator *ref;

	/* 8, 10 or 12 */
	int bits;
};

#define REG_CONV_RES 0x00

static int adc081c_read_raw(struct iio_dev *iio,
			    struct iio_chan_spec const *channel, int *value,
			    int *shift, long mask)
{
	struct adc081c *adc = iio_priv(iio);
	int err;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES);
		if (err < 0)
			return err;

		*value = (err & 0xFFF) >> (12 - adc->bits);
		return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:
		err = regulator_get_voltage(adc->ref);
		if (err < 0)
			return err;

		*value = err / 1000;
		*shift = adc->bits;

		return IIO_VAL_FRACTIONAL_LOG2;

	default:
		break;
	}

	return -EINVAL;
}

#define ADCxx1C_CHAN(_bits) {					\
	.type = IIO_VOLTAGE,					\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
	.scan_type = {						\
		.sign = 'u',					\
		.realbits = (_bits),				\
		.storagebits = 16,				\
		.shift = 12 - (_bits),				\
		.endianness = IIO_CPU,				\
	},							\
}

#define DEFINE_ADCxx1C_CHANNELS(_name, _bits)				\
	static const struct iio_chan_spec _name ## _channels[] = {	\
		ADCxx1C_CHAN((_bits)),					\
		IIO_CHAN_SOFT_TIMESTAMP(1),				\
	};								\

#define ADC081C_NUM_CHANNELS 2

struct adcxx1c_model {
	const struct iio_chan_spec* channels;
	int bits;
};

#define ADCxx1C_MODEL(_name, _bits)					\
	{								\
		.channels = _name ## _channels,				\
		.bits = (_bits),					\
	}

DEFINE_ADCxx1C_CHANNELS(adc081c,  8);
DEFINE_ADCxx1C_CHANNELS(adc101c, 10);
DEFINE_ADCxx1C_CHANNELS(adc121c, 12);

/* Model ids are indexes in _models array */
enum adcxx1c_model_id {
	ADC081C = 0,
	ADC101C = 1,
	ADC121C = 2,
};

static struct adcxx1c_model adcxx1c_models[] = {
	ADCxx1C_MODEL(adc081c,  8),
	ADCxx1C_MODEL(adc101c, 10),
	ADCxx1C_MODEL(adc121c, 12),
};

static const struct iio_info adc081c_info = {
	.read_raw = adc081c_read_raw,
	.driver_module = THIS_MODULE,
};

static irqreturn_t adc081c_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct adc081c *data = iio_priv(indio_dev);
	u16 buf[8]; /* 2 bytes data + 6 bytes padding + 8 bytes timestamp */
	int ret;

	ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES);
	if (ret < 0)
		goto out;
	buf[0] = ret;
	iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
out:
	iio_trigger_notify_done(indio_dev->trig);
	return IRQ_HANDLED;
}

static int adc081c_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct iio_dev *iio;
	struct adc081c *adc;
	struct adcxx1c_model *model = &adcxx1c_models[id->driver_data];
	int err;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
		return -EOPNOTSUPP;

	iio = devm_iio_device_alloc(&client->dev, sizeof(*adc));
	if (!iio)
		return -ENOMEM;

	adc = iio_priv(iio);
	adc->i2c = client;
	adc->bits = model->bits;

	adc->ref = devm_regulator_get(&client->dev, "vref");
	if (IS_ERR(adc->ref))
		return PTR_ERR(adc->ref);

	err = regulator_enable(adc->ref);
	if (err < 0)
		return err;

	iio->dev.parent = &client->dev;
	iio->name = dev_name(&client->dev);
	iio->modes = INDIO_DIRECT_MODE;
	iio->info = &adc081c_info;

	iio->channels = model->channels;
	iio->num_channels = ADC081C_NUM_CHANNELS;

	err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL);
	if (err < 0) {
		dev_err(&client->dev, "iio triggered buffer setup failed\n");
		goto err_regulator_disable;
	}

	err = iio_device_register(iio);
	if (err < 0)
		goto err_buffer_cleanup;

	i2c_set_clientdata(client, iio);

	return 0;

err_buffer_cleanup:
	iio_triggered_buffer_cleanup(iio);
err_regulator_disable:
	regulator_disable(adc->ref);

	return err;
}

static int adc081c_remove(struct i2c_client *client)
{
	struct iio_dev *iio = i2c_get_clientdata(client);
	struct adc081c *adc = iio_priv(iio);

	iio_device_unregister(iio);
	iio_triggered_buffer_cleanup(iio);
	regulator_disable(adc->ref);

	return 0;
}

static const struct i2c_device_id adc081c_id[] = {
	{ "adc081c", ADC081C },
	{ "adc101c", ADC101C },
	{ "adc121c", ADC121C },
	{ }
};
MODULE_DEVICE_TABLE(i2c, adc081c_id);

#ifdef CONFIG_OF
static const struct of_device_id adc081c_of_match[] = {
	{ .compatible = "ti,adc081c" },
	{ .compatible = "ti,adc101c" },
	{ .compatible = "ti,adc121c" },
	{ }
};
MODULE_DEVICE_TABLE(of, adc081c_of_match);
#endif

static struct i2c_driver adc081c_driver = {
	.driver = {
		.name = "adc081c",
		.of_match_table = of_match_ptr(adc081c_of_match),
	},
	.probe = adc081c_probe,
	.remove = adc081c_remove,
	.id_table = adc081c_id,
};
module_i2c_driver(adc081c_driver);

MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
bc0a409c	1	/*
a6b5ec88 CDL	2	* TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver
a6b5ec88 CDL	3	*
bc0a409c	4	* Copyright (C) 2012 Avionic Design GmbH
a6b5ec88	5	* Copyright (C) 2016 Intel
bc0a409c TR	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
a6b5ec88 CDL	10	*
	11	* Datasheets:
	12	* http://www.ti.com/lit/ds/symlink/adc081c021.pdf
	13	* http://www.ti.com/lit/ds/symlink/adc101c021.pdf
	14	* http://www.ti.com/lit/ds/symlink/adc121c021.pdf
	15	*
	16	* The devices have a very similar interface and differ mostly in the number of
	17	* bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2
	18	* bits of value registers are reserved.
bc0a409c TR	19	*/
	20
	21	#include <linux/err.h>
	22	#include <linux/i2c.h>
	23	#include <linux/module.h>
1f100e80	24	#include <linux/of.h>
bc0a409c TR	25
bc0a409c TR	26	#include <linux/iio/iio.h>
08e05d1f CDL	27	#include <linux/iio/buffer.h>
	28	#include <linux/iio/trigger_consumer.h>
	29	#include <linux/iio/triggered_buffer.h>
bc0a409c TR	30	#include <linux/regulator/consumer.h>
	31
	32	struct adc081c {
	33	struct i2c_client *i2c;
	34	struct regulator *ref;
a6b5ec88 CDL	35
	36	/* 8, 10 or 12 */
	37	int bits;
bc0a409c TR	38	};
	39
	40	#define REG_CONV_RES 0x00
	41
	42	static int adc081c_read_raw(struct iio_dev *iio,
	43	struct iio_chan_spec const channel, int value,
	44	int *shift, long mask)
	45	{
	46	struct adc081c *adc = iio_priv(iio);
	47	int err;
	48
	49	switch (mask) {
	50	case IIO_CHAN_INFO_RAW:
	51	err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES);
	52	if (err < 0)
	53	return err;
	54
a6b5ec88	55	*value = (err & 0xFFF) >> (12 - adc->bits);
bc0a409c TR	56	return IIO_VAL_INT;
	57
	58	case IIO_CHAN_INFO_SCALE:
	59	err = regulator_get_voltage(adc->ref);
	60	if (err < 0)
	61	return err;
	62
	63	*value = err / 1000;
a6b5ec88	64	*shift = adc->bits;
bc0a409c TR	65
	66	return IIO_VAL_FRACTIONAL_LOG2;
	67
	68	default:
	69	break;
	70	}
	71
	72	return -EINVAL;
	73	}
	74
08e05d1f CDL	75	#define ADCxx1C_CHAN(_bits) { \
	76	.type = IIO_VOLTAGE, \
	77	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
	78	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	79	.scan_type = { \
	80	.sign = 'u', \
	81	.realbits = (_bits), \
	82	.storagebits = 16, \
	83	.shift = 12 - (_bits), \
	84	.endianness = IIO_CPU, \
	85	}, \
	86	}
	87
	88	#define DEFINE_ADCxx1C_CHANNELS(_name, _bits) \
	89	static const struct iio_chan_spec _name ## _channels[] = { \
	90	ADCxx1C_CHAN((_bits)), \
	91	IIO_CHAN_SOFT_TIMESTAMP(1), \
	92	}; \
	93
	94	#define ADC081C_NUM_CHANNELS 2
bc0a409c	95
a6b5ec88	96	struct adcxx1c_model {
08e05d1f	97	const struct iio_chan_spec* channels;
a6b5ec88 CDL	98	int bits;
	99	};
	100
08e05d1f	101	#define ADCxx1C_MODEL(_name, _bits) \
a6b5ec88	102	{ \
08e05d1f	103	.channels = _name ## _channels, \
a6b5ec88 CDL	104	.bits = (_bits), \
	105	}
	106
08e05d1f CDL	107	DEFINE_ADCxx1C_CHANNELS(adc081c, 8);
	108	DEFINE_ADCxx1C_CHANNELS(adc101c, 10);
	109	DEFINE_ADCxx1C_CHANNELS(adc121c, 12);
	110
a6b5ec88 CDL	111	/* Model ids are indexes in _models array */
	112	enum adcxx1c_model_id {
	113	ADC081C = 0,
	114	ADC101C = 1,
	115	ADC121C = 2,
	116	};
	117
	118	static struct adcxx1c_model adcxx1c_models[] = {
08e05d1f CDL	119	ADCxx1C_MODEL(adc081c, 8),
	120	ADCxx1C_MODEL(adc101c, 10),
	121	ADCxx1C_MODEL(adc121c, 12),
a6b5ec88 CDL	122	};
a6b5ec88 CDL	123
bc0a409c TR	124	static const struct iio_info adc081c_info = {
	125	.read_raw = adc081c_read_raw,
	126	.driver_module = THIS_MODULE,
	127	};
	128
08e05d1f CDL	129	static irqreturn_t adc081c_trigger_handler(int irq, void *p)
	130	{
	131	struct iio_poll_func *pf = p;
	132	struct iio_dev *indio_dev = pf->indio_dev;
	133	struct adc081c *data = iio_priv(indio_dev);
	134	u16 buf[8]; /* 2 bytes data + 6 bytes padding + 8 bytes timestamp */
	135	int ret;
	136
	137	ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES);
	138	if (ret < 0)
	139	goto out;
	140	buf[0] = ret;
	141	iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
	142	out:
	143	iio_trigger_notify_done(indio_dev->trig);
	144	return IRQ_HANDLED;
	145	}
	146
bc0a409c TR	147	static int adc081c_probe(struct i2c_client *client,
	148	const struct i2c_device_id *id)
	149	{
	150	struct iio_dev *iio;
	151	struct adc081c *adc;
a6b5ec88	152	struct adcxx1c_model *model = &adcxx1c_models[id->driver_data];
bc0a409c TR	153	int err;
	154
	155	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
f8d9d3b4	156	return -EOPNOTSUPP;
bc0a409c	157
99e94b6d	158	iio = devm_iio_device_alloc(&client->dev, sizeof(*adc));
bc0a409c TR	159	if (!iio)
	160	return -ENOMEM;
	161
	162	adc = iio_priv(iio);
	163	adc->i2c = client;
a6b5ec88	164	adc->bits = model->bits;
bc0a409c	165
99e94b6d SK	166	adc->ref = devm_regulator_get(&client->dev, "vref");
	167	if (IS_ERR(adc->ref))
	168	return PTR_ERR(adc->ref);
bc0a409c TR	169
	170	err = regulator_enable(adc->ref);
	171	if (err < 0)
99e94b6d	172	return err;
bc0a409c TR	173
	174	iio->dev.parent = &client->dev;
	175	iio->name = dev_name(&client->dev);
	176	iio->modes = INDIO_DIRECT_MODE;
	177	iio->info = &adc081c_info;
	178
08e05d1f CDL	179	iio->channels = model->channels;
	180	iio->num_channels = ADC081C_NUM_CHANNELS;
	181
	182	err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL);
	183	if (err < 0) {
	184	dev_err(&client->dev, "iio triggered buffer setup failed\n");
	185	goto err_regulator_disable;
	186	}
bc0a409c TR	187
	188	err = iio_device_register(iio);
	189	if (err < 0)
08e05d1f	190	goto err_buffer_cleanup;
bc0a409c TR	191
	192	i2c_set_clientdata(client, iio);
	193
	194	return 0;
	195
08e05d1f CDL	196	err_buffer_cleanup:
	197	iio_triggered_buffer_cleanup(iio);
	198	err_regulator_disable:
bc0a409c	199	regulator_disable(adc->ref);
bc0a409c TR	200
	201	return err;
	202	}
	203
	204	static int adc081c_remove(struct i2c_client *client)
	205	{
	206	struct iio_dev *iio = i2c_get_clientdata(client);
	207	struct adc081c *adc = iio_priv(iio);
	208
	209	iio_device_unregister(iio);
08e05d1f	210	iio_triggered_buffer_cleanup(iio);
bc0a409c	211	regulator_disable(adc->ref);
bc0a409c TR	212
	213	return 0;
	214	}
	215
	216	static const struct i2c_device_id adc081c_id[] = {
a6b5ec88 CDL	217	{ "adc081c", ADC081C },
	218	{ "adc101c", ADC101C },
	219	{ "adc121c", ADC121C },
bc0a409c TR	220	{ }
	221	};
	222	MODULE_DEVICE_TABLE(i2c, adc081c_id);
	223
	224	#ifdef CONFIG_OF
	225	static const struct of_device_id adc081c_of_match[] = {
	226	{ .compatible = "ti,adc081c" },
a6b5ec88 CDL	227	{ .compatible = "ti,adc101c" },
a6b5ec88 CDL	228	{ .compatible = "ti,adc121c" },
bc0a409c TR	229	{ }
	230	};
	231	MODULE_DEVICE_TABLE(of, adc081c_of_match);
	232	#endif
	233
	234	static struct i2c_driver adc081c_driver = {
	235	.driver = {
	236	.name = "adc081c",
bc0a409c TR	237	.of_match_table = of_match_ptr(adc081c_of_match),
	238	},
	239	.probe = adc081c_probe,
	240	.remove = adc081c_remove,
	241	.id_table = adc081c_id,
	242	};
	243	module_i2c_driver(adc081c_driver);
	244
	245	MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
a6b5ec88	246	MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver");
bc0a409c	247	MODULE_LICENSE("GPL v2");