[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/interrupt.h>
#include <linux/workqueue.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/list.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>

#include "../iio.h"
#include "../sysfs.h"
#include "../ring_generic.h"
#include "adc.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 ssize_t ad7476_scan(struct device *dev,
			    struct device_attribute *attr,
			    char *buf)
{
	struct iio_dev *dev_info = dev_get_drvdata(dev);
	struct ad7476_state *st = dev_info->dev_data;
	int ret;

	mutex_lock(&dev_info->mlock);
	if (iio_ring_enabled(dev_info))
		ret = ad7476_scan_from_ring(st);
	else
		ret = ad7476_scan_direct(st);
	mutex_unlock(&dev_info->mlock);

	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", (ret >> st->chip_info->res_shift) &
		       RES_MASK(st->chip_info->bits));
}
static IIO_DEV_ATTR_IN_RAW(0, ad7476_scan, 0);

static ssize_t ad7476_show_scale(struct device *dev,
				struct device_attribute *attr,
				char *buf)
{
	/* Driver currently only support internal vref */
	struct iio_dev *dev_info = dev_get_drvdata(dev);
	struct ad7476_state *st = iio_dev_get_devdata(dev_info);
	/* Corresponds to Vref / 2^(bits) */
	unsigned int scale_uv = (st->int_vref_mv * 1000) >> st->chip_info->bits;

	return sprintf(buf, "%d.%d\n", scale_uv / 1000, scale_uv % 1000);
}
static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7476_show_scale, NULL, 0);

static ssize_t ad7476_show_name(struct device *dev,
				 struct device_attribute *attr,
				 char *buf)
{
	struct iio_dev *dev_info = dev_get_drvdata(dev);
	struct ad7476_state *st = iio_dev_get_devdata(dev_info);

	return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
}
static IIO_DEVICE_ATTR(name, S_IRUGO, ad7476_show_name, NULL, 0);

static struct attribute *ad7476_attributes[] = {
	&iio_dev_attr_in0_raw.dev_attr.attr,
	&iio_dev_attr_in_scale.dev_attr.attr,
	&iio_dev_attr_name.dev_attr.attr,
	NULL,
};

static const struct attribute_group ad7476_attribute_group = {
	.attrs = ad7476_attributes,
};

static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
	[ID_AD7466] = {
		.bits = 12,
		.storagebits = 16,
		.res_shift = 0,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7467] = {
		.bits = 10,
		.storagebits = 16,
		.res_shift = 2,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7468] = {
		.bits = 8,
		.storagebits = 16,
		.res_shift = 4,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7475] = {
		.bits = 12,
		.storagebits = 16,
		.res_shift = 0,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7476] = {
		.bits = 12,
		.storagebits = 16,
		.res_shift = 0,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7477] = {
		.bits = 10,
		.storagebits = 16,
		.res_shift = 2,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7478] = {
		.bits = 8,
		.storagebits = 16,
		.res_shift = 4,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
	[ID_AD7495] = {
		.bits = 12,
		.storagebits = 16,
		.res_shift = 0,
		.int_vref_mv = 2500,
		.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	},
};

static int __devinit ad7476_probe(struct spi_device *spi)
{
	struct ad7476_platform_data *pdata = spi->dev.platform_data;
	struct ad7476_state *st;
	int ret, voltage_uv = 0;

	st = kzalloc(sizeof(*st), GFP_KERNEL);
	if (st == NULL) {
		ret = -ENOMEM;
		goto error_ret;
	}

	st->reg = regulator_get(&spi->dev, "vcc");
	if (!IS_ERR(st->reg)) {
		ret = regulator_enable(st->reg);
		if (ret)
			goto error_put_reg;

		voltage_uv = regulator_get_voltage(st->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, st);

	atomic_set(&st->protect_ring, 0);
	st->spi = spi;

	st->indio_dev = iio_allocate_device();
	if (st->indio_dev == NULL) {
		ret = -ENOMEM;
		goto error_disable_reg;
	}

	/* Estabilish that the iio_dev is a child of the i2c device */
	st->indio_dev->dev.parent = &spi->dev;
	st->indio_dev->attrs = &ad7476_attribute_group;
	st->indio_dev->dev_data = (void *)(st);
	st->indio_dev->driver_module = THIS_MODULE;
	st->indio_dev->modes = INDIO_DIRECT_MODE;

	/* Setup default message */

	st->xfer.rx_buf = &st->data;
	st->xfer.len = st->chip_info->storagebits / 8;

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

	ret = ad7476_register_ring_funcs_and_init(st->indio_dev);
	if (ret)
		goto error_free_device;

	ret = iio_device_register(st->indio_dev);
	if (ret)
		goto error_free_device;

	ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
	if (ret)
		goto error_cleanup_ring;
	return 0;

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

static int ad7476_remove(struct spi_device *spi)
{
	struct ad7476_state *st = spi_get_drvdata(spi);
	struct iio_dev *indio_dev = st->indio_dev;
	iio_ring_buffer_unregister(indio_dev->ring);
	ad7476_ring_cleanup(indio_dev);
	iio_device_unregister(indio_dev);
	if (!IS_ERR(st->reg)) {
		regulator_disable(st->reg);
		regulator_put(st->reg);
	}
	kfree(st);
	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
	9	#include <linux/interrupt.h>
	10	#include <linux/workqueue.h>
	11	#include <linux/device.h>
	12	#include <linux/kernel.h>
	13	#include <linux/slab.h>
	14	#include <linux/sysfs.h>
	15	#include <linux/list.h>
	16	#include <linux/spi/spi.h>
	17	#include <linux/regulator/consumer.h>
	18	#include <linux/err.h>
	19
	20	#include "../iio.h"
	21	#include "../sysfs.h"
	22	#include "../ring_generic.h"
	23	#include "adc.h"
	24
	25	#include "ad7476.h"
	26
	27	static int ad7476_scan_direct(struct ad7476_state *st)
	28	{
349282d8 MH	29	int ret;
349282d8 MH	30
668413e9	31	ret = spi_sync(st->spi, &st->msg);
349282d8 MH	32	if (ret)
	33	return ret;
	34
	35	return (st->data[0] << 8) \| st->data[1];
	36	}
	37
	38	static ssize_t ad7476_scan(struct device *dev,
	39	struct device_attribute *attr,
	40	char *buf)
	41	{
	42	struct iio_dev *dev_info = dev_get_drvdata(dev);
	43	struct ad7476_state *st = dev_info->dev_data;
	44	int ret;
	45
	46	mutex_lock(&dev_info->mlock);
	47	if (iio_ring_enabled(dev_info))
	48	ret = ad7476_scan_from_ring(st);
	49	else
	50	ret = ad7476_scan_direct(st);
	51	mutex_unlock(&dev_info->mlock);
	52
	53	if (ret < 0)
	54	return ret;
	55
	56	return sprintf(buf, "%d\n", (ret >> st->chip_info->res_shift) &
	57	RES_MASK(st->chip_info->bits));
	58	}
	59	static IIO_DEV_ATTR_IN_RAW(0, ad7476_scan, 0);
	60
	61	static ssize_t ad7476_show_scale(struct device *dev,
	62	struct device_attribute *attr,
	63	char *buf)
	64	{
	65	/* Driver currently only support internal vref */
	66	struct iio_dev *dev_info = dev_get_drvdata(dev);
	67	struct ad7476_state *st = iio_dev_get_devdata(dev_info);
	68	/* Corresponds to Vref / 2^(bits) */
668413e9	69	unsigned int scale_uv = (st->int_vref_mv * 1000) >> st->chip_info->bits;
349282d8	70
668413e9	71	return sprintf(buf, "%d.%d\n", scale_uv / 1000, scale_uv % 1000);
349282d8 MH	72	}
	73	static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7476_show_scale, NULL, 0);
	74
	75	static ssize_t ad7476_show_name(struct device *dev,
	76	struct device_attribute *attr,
	77	char *buf)
	78	{
	79	struct iio_dev *dev_info = dev_get_drvdata(dev);
	80	struct ad7476_state *st = iio_dev_get_devdata(dev_info);
	81
	82	return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
	83	}
	84	static IIO_DEVICE_ATTR(name, S_IRUGO, ad7476_show_name, NULL, 0);
	85
	86	static struct attribute *ad7476_attributes[] = {
	87	&iio_dev_attr_in0_raw.dev_attr.attr,
	88	&iio_dev_attr_in_scale.dev_attr.attr,
	89	&iio_dev_attr_name.dev_attr.attr,
	90	NULL,
	91	};
	92
	93	static const struct attribute_group ad7476_attribute_group = {
	94	.attrs = ad7476_attributes,
	95	};
	96
	97	static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
	98	[ID_AD7466] = {
	99	.bits = 12,
	100	.storagebits = 16,
	101	.res_shift = 0,
	102	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	103	},
	104	[ID_AD7467] = {
	105	.bits = 10,
	106	.storagebits = 16,
	107	.res_shift = 2,
	108	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	109	},
	110	[ID_AD7468] = {
	111	.bits = 8,
	112	.storagebits = 16,
	113	.res_shift = 4,
	114	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	115	},
	116	[ID_AD7475] = {
	117	.bits = 12,
	118	.storagebits = 16,
	119	.res_shift = 0,
	120	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	121	},
	122	[ID_AD7476] = {
	123	.bits = 12,
	124	.storagebits = 16,
	125	.res_shift = 0,
	126	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	127	},
	128	[ID_AD7477] = {
	129	.bits = 10,
	130	.storagebits = 16,
	131	.res_shift = 2,
	132	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
	133	},
	134	[ID_AD7478] = {
	135	.bits = 8,
136	.storagebits = 16,
137	.res_shift = 4,
138	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
139	},
140	[ID_AD7495] = {
141	.bits = 12,
142	.storagebits = 16,
143	.res_shift = 0,
144	.int_vref_mv = 2500,
145	.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
146	},
147	};
148
149	static int __devinit ad7476_probe(struct spi_device *spi)
150	{
151	struct ad7476_platform_data *pdata = spi->dev.platform_data;
152	struct ad7476_state *st;
153	int ret, voltage_uv = 0;
154
155	st = kzalloc(sizeof(*st), GFP_KERNEL);
156	if (st == NULL) {
157	ret = -ENOMEM;
158	goto error_ret;
159	}
160
161	st->reg = regulator_get(&spi->dev, "vcc");
162	if (!IS_ERR(st->reg)) {
163	ret = regulator_enable(st->reg);
164	if (ret)
165	goto error_put_reg;
166
167	voltage_uv = regulator_get_voltage(st->reg);
168	}
169
170	st->chip_info =
171	&ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];
172
173	if (st->chip_info->int_vref_mv)
174	st->int_vref_mv = st->chip_info->int_vref_mv;
175	else if (pdata && pdata->vref_mv)
176	st->int_vref_mv = pdata->vref_mv;
177	else if (voltage_uv)
178	st->int_vref_mv = voltage_uv / 1000;
179	else
180	dev_warn(&spi->dev, "reference voltage unspecified\n");
181
182	spi_set_drvdata(spi, st);
183
184	atomic_set(&st->protect_ring, 0);
185	st->spi = spi;
186
187	st->indio_dev = iio_allocate_device();
188	if (st->indio_dev == NULL) {
189	ret = -ENOMEM;
190	goto error_disable_reg;
191	}
192
193	/* Estabilish that the iio_dev is a child of the i2c device */
194	st->indio_dev->dev.parent = &spi->dev;
195	st->indio_dev->attrs = &ad7476_attribute_group;
196	st->indio_dev->dev_data = (void *)(st);
197	st->indio_dev->driver_module = THIS_MODULE;
198	st->indio_dev->modes = INDIO_DIRECT_MODE;
199
200	/* Setup default message */
201
202	st->xfer.rx_buf = &st->data;
203	st->xfer.len = st->chip_info->storagebits / 8;
204
205	spi_message_init(&st->msg);
206	spi_message_add_tail(&st->xfer, &st->msg);
207
208	ret = ad7476_register_ring_funcs_and_init(st->indio_dev);
209	if (ret)
210	goto error_free_device;
211
212	ret = iio_device_register(st->indio_dev);
213	if (ret)
214	goto error_free_device;
215
216	ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
217	if (ret)
218	goto error_cleanup_ring;
219	return 0;
220
221	error_cleanup_ring:
222	ad7476_ring_cleanup(st->indio_dev);
223	iio_device_unregister(st->indio_dev);
224	error_free_device:
225	iio_free_device(st->indio_dev);
226	error_disable_reg:
227	if (!IS_ERR(st->reg))
228	regulator_disable(st->reg);
229	error_put_reg:
230	if (!IS_ERR(st->reg))
231	regulator_put(st->reg);
232	kfree(st);
233	error_ret:
234	return ret;
235	}
236
237	static int ad7476_remove(struct spi_device *spi)
238	{
239	struct ad7476_state *st = spi_get_drvdata(spi);
240	struct iio_dev *indio_dev = st->indio_dev;
241	iio_ring_buffer_unregister(indio_dev->ring);
242	ad7476_ring_cleanup(indio_dev);
243	iio_device_unregister(indio_dev);
244	if (!IS_ERR(st->reg)) {
245	regulator_disable(st->reg);
246	regulator_put(st->reg);
247	}
248	kfree(st);
249	return 0;
250	}
251
252	static const struct spi_device_id ad7476_id[] = {
253	{"ad7466", ID_AD7466},
254	{"ad7467", ID_AD7467},
255	{"ad7468", ID_AD7468},
256	{"ad7475", ID_AD7475},
257	{"ad7476", ID_AD7476},
258	{"ad7476a", ID_AD7476},
259	{"ad7477", ID_AD7477},
260	{"ad7477a", ID_AD7477},
261	{"ad7478", ID_AD7478},
262	{"ad7478a", ID_AD7478},
263	{"ad7495", ID_AD7495},
264	{}
265	};
266
267	static struct spi_driver ad7476_driver = {
268	.driver = {
269	.name = "ad7476",
270	.bus = &spi_bus_type,
271	.owner = THIS_MODULE,
272	},
273	.probe = ad7476_probe,
274	.remove = __devexit_p(ad7476_remove),
275	.id_table = ad7476_id,
276	};
277
278	static int __init ad7476_init(void)
279	{
280	return spi_register_driver(&ad7476_driver);
281	}
282	module_init(ad7476_init);
283
284	static void __exit ad7476_exit(void)
285	{
286	spi_unregister_driver(&ad7476_driver);
287	}
288	module_exit(ad7476_exit);
289
290	MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
291	MODULE_DESCRIPTION("Analog Devices AD7475/6/7/8(A) AD7466/7/8 ADC");
292	MODULE_LICENSE("GPL v2");
293	MODULE_ALIAS("spi:ad7476");