[deliverable/linux.git] / drivers / staging / iio / adc / ad7476_core.c

/*
 * AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver
 *
 * Copyright 2010 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

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

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

#include "ad7476.h"

static int ad7476_scan_direct(struct ad7476_state *st)
{
	int ret;

	ret = spi_sync(st->spi, &st->msg);
	if (ret)
		return ret;

	return (st->data[0] << 8) | st->data[1];
}

static int ad7476_read_raw(struct iio_dev *dev_info,
			   struct iio_chan_spec const *chan,
			   int *val,
			   int *val2,
			   long m)
{
	int ret;
	struct ad7476_state *st = iio_priv(dev_info);
	unsigned int scale_uv;

	switch (m) {
	case 0:
		mutex_lock(&dev_info->mlock);
		if (iio_ring_enabled(dev_info))
			ret = ad7476_scan_from_ring(dev_info);
		else
			ret = ad7476_scan_direct(st);
		mutex_unlock(&dev_info->mlock);

		if (ret < 0)
			return ret;
		*val = (ret >> st->chip_info->channel[0].scan_type.shift) &
			RES_MASK(st->chip_info->channel[0].scan_type.realbits);
		return IIO_VAL_INT;
	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
		scale_uv = (st->int_vref_mv * 1000)
			>> st->chip_info->channel[0].scan_type.realbits;
		*val =  scale_uv/1000;
		*val2 = (scale_uv%1000)*1000;
		return IIO_VAL_INT_PLUS_MICRO;
	}
	return -EINVAL;
}

static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
	[ID_AD7466] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 12, 16, 0), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7467] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 10, 16, 2), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7468] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1 , 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 8, 16, 4), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7475] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 12, 16, 0), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7476] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 12, 16, 0), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7477] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 10, 16, 2), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7478] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 8, 16, 4), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
	},
	[ID_AD7495] = {
		.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
				       (1 << IIO_CHAN_INFO_SCALE_SHARED),
				       0, 0, IIO_ST('u', 12, 16, 0), 0),
		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
		.int_vref_mv = 2500,
	},
};

static const struct iio_info ad7476_info = {
	.driver_module = THIS_MODULE,
	.read_raw = &ad7476_read_raw,
};

static int __devinit ad7476_probe(struct spi_device *spi)
{
	struct ad7476_platform_data *pdata = spi->dev.platform_data;
	struct ad7476_state *st;
	struct iio_dev *indio_dev;
	int ret, voltage_uv = 0;
	bool reg_done = false;
	struct regulator *reg;

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

		voltage_uv = regulator_get_voltage(reg);
	}
	st->reg = reg;
	st->chip_info =
		&ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];

	if (st->chip_info->int_vref_mv)
		st->int_vref_mv = st->chip_info->int_vref_mv;
	else if (pdata && pdata->vref_mv)
		st->int_vref_mv = pdata->vref_mv;
	else if (voltage_uv)
		st->int_vref_mv = voltage_uv / 1000;
	else
		dev_warn(&spi->dev, "reference voltage unspecified\n");

	spi_set_drvdata(spi, indio_dev);

	st->spi = spi;

	/* Establish that the iio_dev is a child of the spi device */
	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi_get_device_id(spi)->name;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = st->chip_info->channel;
	indio_dev->num_channels = 2;
	indio_dev->info = &ad7476_info;
	/* Setup default message */

	st->xfer.rx_buf = &st->data;
	st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8;

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

	ret = ad7476_register_ring_funcs_and_init(indio_dev);
	if (ret)
		goto error_disable_reg;

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

	ret = iio_ring_buffer_register_ex(indio_dev, 0,
					  st->chip_info->channel,
					  ARRAY_SIZE(st->chip_info->channel));
	if (ret)
		goto error_cleanup_ring;
	return 0;

error_cleanup_ring:
	ad7476_ring_cleanup(indio_dev);
	iio_device_unregister(indio_dev);
error_disable_reg:
	if (!IS_ERR(reg))
		regulator_disable(st->reg);
error_put_reg:
	if (!IS_ERR(reg))
		regulator_put(reg);
	if (!reg_done)
		iio_free_device(indio_dev);
error_ret:
	return ret;
}

static int ad7476_remove(struct spi_device *spi)
{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct ad7476_state *st = iio_priv(indio_dev);
	/* copy needed as st will have been freed */
	struct regulator *reg = st->reg;

	iio_ring_buffer_unregister(indio_dev);
	ad7476_ring_cleanup(indio_dev);
	iio_device_unregister(indio_dev);
	if (!IS_ERR(reg)) {
		regulator_disable(reg);
		regulator_put(reg);
	}

	return 0;
}

static const struct spi_device_id ad7476_id[] = {
	{"ad7466", ID_AD7466},
	{"ad7467", ID_AD7467},
	{"ad7468", ID_AD7468},
	{"ad7475", ID_AD7475},
	{"ad7476", ID_AD7476},
	{"ad7476a", ID_AD7476},
	{"ad7477", ID_AD7477},
	{"ad7477a", ID_AD7477},
	{"ad7478", ID_AD7478},
	{"ad7478a", ID_AD7478},
	{"ad7495", ID_AD7495},
	{}
};

static struct spi_driver ad7476_driver = {
	.driver = {
		.name	= "ad7476",
		.bus	= &spi_bus_type,
		.owner	= THIS_MODULE,
	},
	.probe		= ad7476_probe,
	.remove		= __devexit_p(ad7476_remove),
	.id_table	= ad7476_id,
};

static int __init ad7476_init(void)
{
	return spi_register_driver(&ad7476_driver);
}
module_init(ad7476_init);

static void __exit ad7476_exit(void)
{
	spi_unregister_driver(&ad7476_driver);
}
module_exit(ad7476_exit);

MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD7475/6/7/8(A) AD7466/7/8 ADC");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("spi:ad7476");
Commit	Line	Data
349282d8 MH	1	/*
	2	* AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver
	3	*
	4	* Copyright 2010 Analog Devices Inc.
	5	*
	6	* Licensed under the GPL-2 or later.
	7	*/
	8
349282d8 MH	9	#include <linux/device.h>
	10	#include <linux/kernel.h>
	11	#include <linux/slab.h>
	12	#include <linux/sysfs.h>
349282d8 MH	13	#include <linux/spi/spi.h>
	14	#include <linux/regulator/consumer.h>
	15	#include <linux/err.h>
99c97852	16	#include <linux/module.h>
349282d8 MH	17
	18	#include "../iio.h"
	19	#include "../sysfs.h"
	20	#include "../ring_generic.h"
349282d8 MH	21
	22	#include "ad7476.h"
	23
	24	static int ad7476_scan_direct(struct ad7476_state *st)
	25	{
349282d8 MH	26	int ret;
349282d8 MH	27
668413e9	28	ret = spi_sync(st->spi, &st->msg);
349282d8 MH	29	if (ret)
	30	return ret;
	31
	32	return (st->data[0] << 8) \| st->data[1];
	33	}
	34
c5e0819e JC	35	static int ad7476_read_raw(struct iio_dev *dev_info,
	36	struct iio_chan_spec const *chan,
	37	int *val,
	38	int *val2,
	39	long m)
349282d8	40	{
349282d8	41	int ret;
67688105	42	struct ad7476_state *st = iio_priv(dev_info);
c5e0819e JC	43	unsigned int scale_uv;
	44
	45	switch (m) {
	46	case 0:
	47	mutex_lock(&dev_info->mlock);
	48	if (iio_ring_enabled(dev_info))
67688105	49	ret = ad7476_scan_from_ring(dev_info);
c5e0819e JC	50	else
	51	ret = ad7476_scan_direct(st);
	52	mutex_unlock(&dev_info->mlock);
	53
	54	if (ret < 0)
	55	return ret;
	56	*val = (ret >> st->chip_info->channel[0].scan_type.shift) &
	57	RES_MASK(st->chip_info->channel[0].scan_type.realbits);
	58	return IIO_VAL_INT;
	59	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
	60	scale_uv = (st->int_vref_mv * 1000)
	61	>> st->chip_info->channel[0].scan_type.realbits;
	62	*val = scale_uv/1000;
	63	val2 = (scale_uv%1000)1000;
	64	return IIO_VAL_INT_PLUS_MICRO;
	65	}
	66	return -EINVAL;
349282d8	67	}
349282d8	68
349282d8 MH	69	static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
349282d8 MH	70	[ID_AD7466] = {
c5e0819e JC	71	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	72	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	73	0, 0, IIO_ST('u', 12, 16, 0), 0),
	74	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	75	},
349282d8 MH	76	[ID_AD7467] = {
c5e0819e JC	77	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	78	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	79	0, 0, IIO_ST('u', 10, 16, 2), 0),
	80	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	81	},
349282d8 MH	82	[ID_AD7468] = {
c5e0819e JC	83	.channel[0] = IIO_CHAN(IIO_IN, 0, 1 , 0, NULL, 0, 0,
	84	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	85	0, 0, IIO_ST('u', 8, 16, 4), 0),
	86	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	87	},
349282d8 MH	88	[ID_AD7475] = {
c5e0819e JC	89	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	90	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	91	0, 0, IIO_ST('u', 12, 16, 0), 0),
	92	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	93	},
349282d8 MH	94	[ID_AD7476] = {
c5e0819e JC	95	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	96	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	97	0, 0, IIO_ST('u', 12, 16, 0), 0),
	98	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	99	},
349282d8 MH	100	[ID_AD7477] = {
c5e0819e JC	101	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	102	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	103	0, 0, IIO_ST('u', 10, 16, 2), 0),
	104	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	105	},
349282d8 MH	106	[ID_AD7478] = {
c5e0819e JC	107	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	108	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	109	0, 0, IIO_ST('u', 8, 16, 4), 0),
	110	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8 MH	111	},
349282d8 MH	112	[ID_AD7495] = {
c5e0819e JC	113	.channel[0] = IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 0, 0,
	114	(1 << IIO_CHAN_INFO_SCALE_SHARED),
	115	0, 0, IIO_ST('u', 12, 16, 0), 0),
	116	.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
349282d8	117	.int_vref_mv = 2500,
349282d8 MH	118	},
	119	};
	120
6fe8135f JC	121	static const struct iio_info ad7476_info = {
	122	.driver_module = THIS_MODULE,
	123	.read_raw = &ad7476_read_raw,
	124	};
	125
349282d8 MH	126	static int __devinit ad7476_probe(struct spi_device *spi)
	127	{
	128	struct ad7476_platform_data *pdata = spi->dev.platform_data;
	129	struct ad7476_state *st;
67688105	130	struct iio_dev *indio_dev;
349282d8	131	int ret, voltage_uv = 0;
67688105 JC	132	bool reg_done = false;
67688105 JC	133	struct regulator *reg;
349282d8	134
67688105 JC	135	indio_dev = iio_allocate_device(sizeof(*st));
67688105 JC	136	if (indio_dev == NULL) {
349282d8 MH	137	ret = -ENOMEM;
	138	goto error_ret;
	139	}
67688105 JC	140	st = iio_priv(indio_dev);
	141	reg = regulator_get(&spi->dev, "vcc");
	142	if (!IS_ERR(reg)) {
	143	ret = regulator_enable(reg);
349282d8 MH	144	if (ret)
	145	goto error_put_reg;
	146
67688105	147	voltage_uv = regulator_get_voltage(reg);
349282d8	148	}
67688105	149	st->reg = reg;
349282d8 MH	150	st->chip_info =
	151	&ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];
	152
	153	if (st->chip_info->int_vref_mv)
	154	st->int_vref_mv = st->chip_info->int_vref_mv;
	155	else if (pdata && pdata->vref_mv)
	156	st->int_vref_mv = pdata->vref_mv;
	157	else if (voltage_uv)
	158	st->int_vref_mv = voltage_uv / 1000;
	159	else
	160	dev_warn(&spi->dev, "reference voltage unspecified\n");
	161
38f71aa9	162	spi_set_drvdata(spi, indio_dev);
349282d8	163
349282d8 MH	164	st->spi = spi;
349282d8 MH	165
ae639830	166	/* Establish that the iio_dev is a child of the spi device */
67688105 JC	167	indio_dev->dev.parent = &spi->dev;
	168	indio_dev->name = spi_get_device_id(spi)->name;
	169	indio_dev->modes = INDIO_DIRECT_MODE;
	170	indio_dev->channels = st->chip_info->channel;
	171	indio_dev->num_channels = 2;
	172	indio_dev->info = &ad7476_info;
349282d8 MH	173	/* Setup default message */
	174
	175	st->xfer.rx_buf = &st->data;
c5e0819e	176	st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8;
349282d8 MH	177
	178	spi_message_init(&st->msg);
	179	spi_message_add_tail(&st->xfer, &st->msg);
	180
67688105	181	ret = ad7476_register_ring_funcs_and_init(indio_dev);
349282d8	182	if (ret)
67688105	183	goto error_disable_reg;
349282d8	184
67688105	185	ret = iio_device_register(indio_dev);
349282d8	186	if (ret)
67688105	187	goto error_disable_reg;
349282d8	188
1aa04278	189	ret = iio_ring_buffer_register_ex(indio_dev, 0,
c5e0819e JC	190	st->chip_info->channel,
c5e0819e JC	191	ARRAY_SIZE(st->chip_info->channel));
349282d8 MH	192	if (ret)
	193	goto error_cleanup_ring;
	194	return 0;
	195
	196	error_cleanup_ring:
67688105 JC	197	ad7476_ring_cleanup(indio_dev);
67688105 JC	198	iio_device_unregister(indio_dev);
349282d8	199	error_disable_reg:
67688105	200	if (!IS_ERR(reg))
349282d8 MH	201	regulator_disable(st->reg);
349282d8 MH	202	error_put_reg:
67688105 JC	203	if (!IS_ERR(reg))
	204	regulator_put(reg);
	205	if (!reg_done)
	206	iio_free_device(indio_dev);
349282d8 MH	207	error_ret:
	208	return ret;
	209	}
	210
	211	static int ad7476_remove(struct spi_device *spi)
	212	{
67688105 JC	213	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	214	struct ad7476_state *st = iio_priv(indio_dev);
	215	/* copy needed as st will have been freed */
	216	struct regulator *reg = st->reg;
	217
1aa04278	218	iio_ring_buffer_unregister(indio_dev);
349282d8 MH	219	ad7476_ring_cleanup(indio_dev);
349282d8 MH	220	iio_device_unregister(indio_dev);
67688105 JC	221	if (!IS_ERR(reg)) {
	222	regulator_disable(reg);
	223	regulator_put(reg);
349282d8	224	}
67688105	225
349282d8 MH	226	return 0;
	227	}
	228
	229	static const struct spi_device_id ad7476_id[] = {
	230	{"ad7466", ID_AD7466},
	231	{"ad7467", ID_AD7467},
	232	{"ad7468", ID_AD7468},
	233	{"ad7475", ID_AD7475},
	234	{"ad7476", ID_AD7476},
	235	{"ad7476a", ID_AD7476},
	236	{"ad7477", ID_AD7477},
	237	{"ad7477a", ID_AD7477},
	238	{"ad7478", ID_AD7478},
	239	{"ad7478a", ID_AD7478},
	240	{"ad7495", ID_AD7495},
	241	{}
	242	};
	243
	244	static struct spi_driver ad7476_driver = {
	245	.driver = {
	246	.name = "ad7476",
	247	.bus = &spi_bus_type,
	248	.owner = THIS_MODULE,
	249	},
	250	.probe = ad7476_probe,
	251	.remove = __devexit_p(ad7476_remove),
	252	.id_table = ad7476_id,
	253	};
	254
	255	static int __init ad7476_init(void)
	256	{
	257	return spi_register_driver(&ad7476_driver);
	258	}
	259	module_init(ad7476_init);
	260
	261	static void __exit ad7476_exit(void)
	262	{
	263	spi_unregister_driver(&ad7476_driver);
	264	}
	265	module_exit(ad7476_exit);
	266
	267	MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
	268	MODULE_DESCRIPTION("Analog Devices AD7475/6/7/8(A) AD7466/7/8 ADC");
	269	MODULE_LICENSE("GPL v2");
	270	MODULE_ALIAS("spi:ad7476");