[mirror_ubuntu-bionic-kernel.git] / drivers / iio / light / tcs3472.c

/*
 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter
 *
 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * 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.
 *
 * Color light sensor with 16-bit channels for red, green, blue, clear);
 * 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725,
 * TCS34727)
 *
 * Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf
 *
 * TODO: interrupt support, thresholds, wait time
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/pm.h>

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

#define TCS3472_DRV_NAME "tcs3472"

#define TCS3472_COMMAND BIT(7)
#define TCS3472_AUTO_INCR BIT(5)

#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)
#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)
#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)
#define TCS3472_AILT (TCS3472_COMMAND | 0x04)
#define TCS3472_AIHT (TCS3472_COMMAND | 0x06)
#define TCS3472_PERS (TCS3472_COMMAND | 0x0c)
#define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d)
#define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f)
#define TCS3472_ID (TCS3472_COMMAND | 0x12)
#define TCS3472_STATUS (TCS3472_COMMAND | 0x13)
#define TCS3472_CDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x14)
#define TCS3472_RDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x16)
#define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18)
#define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a)

#define TCS3472_STATUS_AVALID BIT(0)
#define TCS3472_ENABLE_AEN BIT(1)
#define TCS3472_ENABLE_PON BIT(0)
#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1))

struct tcs3472_data {
	struct i2c_client *client;
	u8 enable;
	u8 control;
	u8 atime;
	u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
};

#define TCS3472_CHANNEL(_color, _si, _addr) { \
	.type = IIO_INTENSITY, \
	.modified = 1, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) | \
		BIT(IIO_CHAN_INFO_INT_TIME), \
	.channel2 = IIO_MOD_LIGHT_##_color, \
	.address = _addr, \
	.scan_index = _si, \
	.scan_type = { \
		.sign = 'u', \
		.realbits = 16, \
		.storagebits = 16, \
		.endianness = IIO_CPU, \
	}, \
}

static const int tcs3472_agains[] = { 1, 4, 16, 60 };

static const struct iio_chan_spec tcs3472_channels[] = {
	TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA),
	TCS3472_CHANNEL(RED, 1, TCS3472_RDATA),
	TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA),
	TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA),
	IIO_CHAN_SOFT_TIMESTAMP(4),
};

static int tcs3472_req_data(struct tcs3472_data *data)
{
	int tries = 50;
	int ret;

	while (tries--) {
		ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
		if (ret < 0)
			return ret;
		if (ret & TCS3472_STATUS_AVALID)
			break;
		msleep(20);
	}

	if (tries < 0) {
		dev_err(&data->client->dev, "data not ready\n");
		return -EIO;
	}

	return 0;
}

static int tcs3472_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long mask)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = iio_device_claim_direct_mode(indio_dev);
		if (ret)
			return ret;
		ret = tcs3472_req_data(data);
		if (ret < 0) {
			iio_device_release_direct_mode(indio_dev);
			return ret;
		}
		ret = i2c_smbus_read_word_data(data->client, chan->address);
		iio_device_release_direct_mode(indio_dev);
		if (ret < 0)
			return ret;
		*val = ret;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_CALIBSCALE:
		*val = tcs3472_agains[data->control &
			TCS3472_CONTROL_AGAIN_MASK];
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_INT_TIME:
		*val = 0;
		*val2 = (256 - data->atime) * 2400;
		return IIO_VAL_INT_PLUS_MICRO;
	}
	return -EINVAL;
}

static int tcs3472_write_raw(struct iio_dev *indio_dev,
			       struct iio_chan_spec const *chan,
			       int val, int val2, long mask)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int i;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBSCALE:
		if (val2 != 0)
			return -EINVAL;
		for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) {
			if (val == tcs3472_agains[i]) {
				data->control &= ~TCS3472_CONTROL_AGAIN_MASK;
				data->control |= i;
				return i2c_smbus_write_byte_data(
					data->client, TCS3472_CONTROL,
					data->control);
			}
		}
		return -EINVAL;
	case IIO_CHAN_INFO_INT_TIME:
		if (val != 0)
			return -EINVAL;
		for (i = 0; i < 256; i++) {
			if (val2 == (256 - i) * 2400) {
				data->atime = i;
				return i2c_smbus_write_byte_data(
					data->client, TCS3472_ATIME,
					data->atime);
			}

		}
		return -EINVAL;
	}
	return -EINVAL;
}

static irqreturn_t tcs3472_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct tcs3472_data *data = iio_priv(indio_dev);
	int i, j = 0;

	int ret = tcs3472_req_data(data);
	if (ret < 0)
		goto done;

	for_each_set_bit(i, indio_dev->active_scan_mask,
		indio_dev->masklength) {
		ret = i2c_smbus_read_word_data(data->client,
			TCS3472_CDATA + 2*i);
		if (ret < 0)
			goto done;

		data->buffer[j++] = ret;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
		iio_get_time_ns(indio_dev));

done:
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

static ssize_t tcs3472_show_int_time_available(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	size_t len = 0;
	int i;

	for (i = 1; i <= 256; i++)
		len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",
			2400 * i);

	/* replace trailing space by newline */
	buf[len - 1] = '\n';

	return len;
}

static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");
static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);

static struct attribute *tcs3472_attributes[] = {
	&iio_const_attr_calibscale_available.dev_attr.attr,
	&iio_dev_attr_integration_time_available.dev_attr.attr,
	NULL
};

static const struct attribute_group tcs3472_attribute_group = {
	.attrs = tcs3472_attributes,
};

static const struct iio_info tcs3472_info = {
	.read_raw = tcs3472_read_raw,
	.write_raw = tcs3472_write_raw,
	.attrs = &tcs3472_attribute_group,
	.driver_module = THIS_MODULE,
};

static int tcs3472_probe(struct i2c_client *client,
			   const struct i2c_device_id *id)
{
	struct tcs3472_data *data;
	struct iio_dev *indio_dev;
	int ret;

	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;

	indio_dev->dev.parent = &client->dev;
	indio_dev->info = &tcs3472_info;
	indio_dev->name = TCS3472_DRV_NAME;
	indio_dev->channels = tcs3472_channels;
	indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);
	if (ret < 0)
		return ret;

	if (ret == 0x44)
		dev_info(&client->dev, "TCS34721/34725 found\n");
	else if (ret == 0x4d)
		dev_info(&client->dev, "TCS34723/34727 found\n");
	else
		return -ENODEV;

	ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);
	if (ret < 0)
		return ret;
	data->control = ret;

	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);
	if (ret < 0)
		return ret;
	data->atime = ret;

	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
	if (ret < 0)
		return ret;

	/* enable device */
	data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN;
	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
		data->enable);
	if (ret < 0)
		return ret;

	ret = iio_triggered_buffer_setup(indio_dev, NULL,
		tcs3472_trigger_handler, NULL);
	if (ret < 0)
		return ret;

	ret = iio_device_register(indio_dev);
	if (ret < 0)
		goto buffer_cleanup;

	return 0;

buffer_cleanup:
	iio_triggered_buffer_cleanup(indio_dev);
	return ret;
}

static int tcs3472_powerdown(struct tcs3472_data *data)
{
	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
		data->enable & ~(TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
}

static int tcs3472_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);

	iio_device_unregister(indio_dev);
	iio_triggered_buffer_cleanup(indio_dev);
	tcs3472_powerdown(iio_priv(indio_dev));

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int tcs3472_suspend(struct device *dev)
{
	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	return tcs3472_powerdown(data);
}

static int tcs3472_resume(struct device *dev)
{
	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
		data->enable | (TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
}
#endif

static SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, tcs3472_resume);

static const struct i2c_device_id tcs3472_id[] = {
	{ "tcs3472", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tcs3472_id);

static struct i2c_driver tcs3472_driver = {
	.driver = {
		.name	= TCS3472_DRV_NAME,
		.pm	= &tcs3472_pm_ops,
	},
	.probe		= tcs3472_probe,
	.remove		= tcs3472_remove,
	.id_table	= tcs3472_id,
};
module_i2c_driver(tcs3472_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TCS3472 color light sensors driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
eb869ade PM	1	/*
	2	* tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter
	3	*
	4	* Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
	5	*
	6	* This file is subject to the terms and conditions of version 2 of
	7	* the GNU General Public License. See the file COPYING in the main
	8	* directory of this archive for more details.
	9	*
	10	* Color light sensor with 16-bit channels for red, green, blue, clear);
	11	* 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725,
	12	* TCS34727)
	13	*
ea5c6e26 AM	14	* Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf
ea5c6e26 AM	15	*
eb869ade PM	16	* TODO: interrupt support, thresholds, wait time
	17	*/
	18
	19	#include <linux/module.h>
	20	#include <linux/i2c.h>
	21	#include <linux/delay.h>
	22	#include <linux/pm.h>
	23
	24	#include <linux/iio/iio.h>
	25	#include <linux/iio/sysfs.h>
	26	#include <linux/iio/trigger_consumer.h>
	27	#include <linux/iio/buffer.h>
	28	#include <linux/iio/triggered_buffer.h>
	29
	30	#define TCS3472_DRV_NAME "tcs3472"
	31
	32	#define TCS3472_COMMAND BIT(7)
	33	#define TCS3472_AUTO_INCR BIT(5)
	34
	35	#define TCS3472_ENABLE (TCS3472_COMMAND \| 0x00)
	36	#define TCS3472_ATIME (TCS3472_COMMAND \| 0x01)
	37	#define TCS3472_WTIME (TCS3472_COMMAND \| 0x03)
	38	#define TCS3472_AILT (TCS3472_COMMAND \| 0x04)
	39	#define TCS3472_AIHT (TCS3472_COMMAND \| 0x06)
	40	#define TCS3472_PERS (TCS3472_COMMAND \| 0x0c)
	41	#define TCS3472_CONFIG (TCS3472_COMMAND \| 0x0d)
	42	#define TCS3472_CONTROL (TCS3472_COMMAND \| 0x0f)
	43	#define TCS3472_ID (TCS3472_COMMAND \| 0x12)
	44	#define TCS3472_STATUS (TCS3472_COMMAND \| 0x13)
	45	#define TCS3472_CDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x14)
	46	#define TCS3472_RDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x16)
	47	#define TCS3472_GDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x18)
	48	#define TCS3472_BDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x1a)
	49
	50	#define TCS3472_STATUS_AVALID BIT(0)
	51	#define TCS3472_ENABLE_AEN BIT(1)
	52	#define TCS3472_ENABLE_PON BIT(0)
	53	#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) \| BIT(1))
	54
	55	struct tcs3472_data {
	56	struct i2c_client *client;
	57	u8 enable;
	58	u8 control;
	59	u8 atime;
6a2f39b7	60	u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
eb869ade PM	61	};
eb869ade PM	62
eb869ade PM	63	#define TCS3472_CHANNEL(_color, _si, _addr) { \
	64	.type = IIO_INTENSITY, \
	65	.modified = 1, \
	66	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	67	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) \| \
	68	BIT(IIO_CHAN_INFO_INT_TIME), \
	69	.channel2 = IIO_MOD_LIGHT_##_color, \
	70	.address = _addr, \
	71	.scan_index = _si, \
6b25f6e6 JC	72	.scan_type = { \
	73	.sign = 'u', \
	74	.realbits = 16, \
	75	.storagebits = 16, \
	76	.endianness = IIO_CPU, \
	77	}, \
eb869ade PM	78	}
	79
	80	static const int tcs3472_agains[] = { 1, 4, 16, 60 };
	81
	82	static const struct iio_chan_spec tcs3472_channels[] = {
	83	TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA),
	84	TCS3472_CHANNEL(RED, 1, TCS3472_RDATA),
	85	TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA),
	86	TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA),
	87	IIO_CHAN_SOFT_TIMESTAMP(4),
	88	};
	89
	90	static int tcs3472_req_data(struct tcs3472_data *data)
	91	{
	92	int tries = 50;
	93	int ret;
	94
	95	while (tries--) {
	96	ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
	97	if (ret < 0)
	98	return ret;
	99	if (ret & TCS3472_STATUS_AVALID)
	100	break;
	101	msleep(20);
	102	}
	103
	104	if (tries < 0) {
	105	dev_err(&data->client->dev, "data not ready\n");
	106	return -EIO;
	107	}
	108
	109	return 0;
	110	}
	111
	112	static int tcs3472_read_raw(struct iio_dev *indio_dev,
	113	struct iio_chan_spec const *chan,
	114	int val, int val2, long mask)
	115	{
	116	struct tcs3472_data *data = iio_priv(indio_dev);
	117	int ret;
	118
	119	switch (mask) {
	120	case IIO_CHAN_INFO_RAW:
95bd363b AS	121	ret = iio_device_claim_direct_mode(indio_dev);
	122	if (ret)
	123	return ret;
eb869ade	124	ret = tcs3472_req_data(data);
2a58b4f8	125	if (ret < 0) {
95bd363b	126	iio_device_release_direct_mode(indio_dev);
eb869ade	127	return ret;
2a58b4f8	128	}
eb869ade	129	ret = i2c_smbus_read_word_data(data->client, chan->address);
95bd363b	130	iio_device_release_direct_mode(indio_dev);
eb869ade PM	131	if (ret < 0)
	132	return ret;
	133	*val = ret;
	134	return IIO_VAL_INT;
	135	case IIO_CHAN_INFO_CALIBSCALE:
	136	*val = tcs3472_agains[data->control &
	137	TCS3472_CONTROL_AGAIN_MASK];
	138	return IIO_VAL_INT;
	139	case IIO_CHAN_INFO_INT_TIME:
	140	*val = 0;
	141	val2 = (256 - data->atime) 2400;
	142	return IIO_VAL_INT_PLUS_MICRO;
	143	}
	144	return -EINVAL;
	145	}
	146
	147	static int tcs3472_write_raw(struct iio_dev *indio_dev,
	148	struct iio_chan_spec const *chan,
	149	int val, int val2, long mask)
	150	{
	151	struct tcs3472_data *data = iio_priv(indio_dev);
	152	int i;
	153
	154	switch (mask) {
	155	case IIO_CHAN_INFO_CALIBSCALE:
	156	if (val2 != 0)
	157	return -EINVAL;
	158	for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) {
	159	if (val == tcs3472_agains[i]) {
	160	data->control &= ~TCS3472_CONTROL_AGAIN_MASK;
	161	data->control \|= i;
	162	return i2c_smbus_write_byte_data(
	163	data->client, TCS3472_CONTROL,
	164	data->control);
	165	}
	166	}
	167	return -EINVAL;
	168	case IIO_CHAN_INFO_INT_TIME:
	169	if (val != 0)
	170	return -EINVAL;
	171	for (i = 0; i < 256; i++) {
	172	if (val2 == (256 - i) * 2400) {
	173	data->atime = i;
53d7d813	174	return i2c_smbus_write_byte_data(
eb869ade PM	175	data->client, TCS3472_ATIME,
	176	data->atime);
	177	}
	178
	179	}
	180	return -EINVAL;
	181	}
	182	return -EINVAL;
	183	}
	184
	185	static irqreturn_t tcs3472_trigger_handler(int irq, void *p)
	186	{
	187	struct iio_poll_func *pf = p;
	188	struct iio_dev *indio_dev = pf->indio_dev;
	189	struct tcs3472_data *data = iio_priv(indio_dev);
eb869ade PM	190	int i, j = 0;
	191
	192	int ret = tcs3472_req_data(data);
	193	if (ret < 0)
	194	goto done;
	195
	196	for_each_set_bit(i, indio_dev->active_scan_mask,
	197	indio_dev->masklength) {
	198	ret = i2c_smbus_read_word_data(data->client,
	199	TCS3472_CDATA + 2*i);
	200	if (ret < 0)
	201	goto done;
	202
	203	data->buffer[j++] = ret;
eb869ade PM	204	}
eb869ade PM	205
0624bf84	206	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
bc2b7dab	207	iio_get_time_ns(indio_dev));
eb869ade PM	208
	209	done:
	210	iio_trigger_notify_done(indio_dev->trig);
	211
	212	return IRQ_HANDLED;
	213	}
	214
	215	static ssize_t tcs3472_show_int_time_available(struct device *dev,
	216	struct device_attribute *attr,
	217	char *buf)
	218	{
	219	size_t len = 0;
	220	int i;
	221
	222	for (i = 1; i <= 256; i++)
	223	len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",
	224	2400 * i);
	225
	226	/* replace trailing space by newline */
	227	buf[len - 1] = '\n';
	228
	229	return len;
	230	}
	231
	232	static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");
	233	static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);
	234
	235	static struct attribute *tcs3472_attributes[] = {
	236	&iio_const_attr_calibscale_available.dev_attr.attr,
	237	&iio_dev_attr_integration_time_available.dev_attr.attr,
	238	NULL
	239	};
	240
	241	static const struct attribute_group tcs3472_attribute_group = {
	242	.attrs = tcs3472_attributes,
	243	};
	244
	245	static const struct iio_info tcs3472_info = {
	246	.read_raw = tcs3472_read_raw,
	247	.write_raw = tcs3472_write_raw,
	248	.attrs = &tcs3472_attribute_group,
	249	.driver_module = THIS_MODULE,
	250	};
	251
	252	static int tcs3472_probe(struct i2c_client *client,
	253	const struct i2c_device_id *id)
	254	{
	255	struct tcs3472_data *data;
	256	struct iio_dev *indio_dev;
	257	int ret;
	258
	259	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	260	if (indio_dev == NULL)
	261	return -ENOMEM;
	262
	263	data = iio_priv(indio_dev);
	264	i2c_set_clientdata(client, indio_dev);
	265	data->client = client;
	266
	267	indio_dev->dev.parent = &client->dev;
	268	indio_dev->info = &tcs3472_info;
	269	indio_dev->name = TCS3472_DRV_NAME;
	270	indio_dev->channels = tcs3472_channels;
	271	indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);
272	indio_dev->modes = INDIO_DIRECT_MODE;
273
274	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);
275	if (ret < 0)
276	return ret;
277
278	if (ret == 0x44)
279	dev_info(&client->dev, "TCS34721/34725 found\n");
280	else if (ret == 0x4d)
281	dev_info(&client->dev, "TCS34723/34727 found\n");
282	else
283	return -ENODEV;
284
285	ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);
286	if (ret < 0)
287	return ret;
288	data->control = ret;
289
290	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);
291	if (ret < 0)
292	return ret;
293	data->atime = ret;
294
295	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
296	if (ret < 0)
297	return ret;
298
299	/* enable device */
300	data->enable = ret \| TCS3472_ENABLE_PON \| TCS3472_ENABLE_AEN;
301	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
302	data->enable);
303	if (ret < 0)
304	return ret;
305
306	ret = iio_triggered_buffer_setup(indio_dev, NULL,
307	tcs3472_trigger_handler, NULL);
308	if (ret < 0)
309	return ret;
310
311	ret = iio_device_register(indio_dev);
312	if (ret < 0)
313	goto buffer_cleanup;
314
315	return 0;
316
317	buffer_cleanup:
318	iio_triggered_buffer_cleanup(indio_dev);
319	return ret;
320	}
321
322	static int tcs3472_powerdown(struct tcs3472_data *data)
323	{
324	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
325	data->enable & ~(TCS3472_ENABLE_AEN \| TCS3472_ENABLE_PON));
326	}
327
328	static int tcs3472_remove(struct i2c_client *client)
329	{
330	struct iio_dev *indio_dev = i2c_get_clientdata(client);
331
332	iio_device_unregister(indio_dev);
333	iio_triggered_buffer_cleanup(indio_dev);
334	tcs3472_powerdown(iio_priv(indio_dev));
335
336	return 0;
337	}
338
339	#ifdef CONFIG_PM_SLEEP
340	static int tcs3472_suspend(struct device *dev)
341	{
4caf279a PM	342	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
	343	to_i2c_client(dev)));
	344	return tcs3472_powerdown(data);
eb869ade PM	345	}
	346
	347	static int tcs3472_resume(struct device *dev)
	348	{
4caf279a PM	349	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
4caf279a PM	350	to_i2c_client(dev)));
eb869ade PM	351	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
	352	data->enable \| (TCS3472_ENABLE_AEN \| TCS3472_ENABLE_PON));
	353	}
	354	#endif
	355
	356	static SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, tcs3472_resume);
	357
	358	static const struct i2c_device_id tcs3472_id[] = {
	359	{ "tcs3472", 0 },
	360	{ }
	361	};
	362	MODULE_DEVICE_TABLE(i2c, tcs3472_id);
	363
	364	static struct i2c_driver tcs3472_driver = {
	365	.driver = {
	366	.name = TCS3472_DRV_NAME,
	367	.pm = &tcs3472_pm_ops,
eb869ade PM	368	},
	369	.probe = tcs3472_probe,
	370	.remove = tcs3472_remove,
	371	.id_table = tcs3472_id,
	372	};
	373	module_i2c_driver(tcs3472_driver);
	374
	375	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
	376	MODULE_DESCRIPTION("TCS3472 color light sensors driver");
	377	MODULE_LICENSE("GPL");