[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)
 *
 * 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_word_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	*
	14	* TODO: interrupt support, thresholds, wait time
	15	*/
	16
	17	#include <linux/module.h>
	18	#include <linux/i2c.h>
	19	#include <linux/delay.h>
	20	#include <linux/pm.h>
	21
	22	#include <linux/iio/iio.h>
	23	#include <linux/iio/sysfs.h>
	24	#include <linux/iio/trigger_consumer.h>
	25	#include <linux/iio/buffer.h>
	26	#include <linux/iio/triggered_buffer.h>
	27
	28	#define TCS3472_DRV_NAME "tcs3472"
	29
	30	#define TCS3472_COMMAND BIT(7)
	31	#define TCS3472_AUTO_INCR BIT(5)
	32
	33	#define TCS3472_ENABLE (TCS3472_COMMAND \| 0x00)
	34	#define TCS3472_ATIME (TCS3472_COMMAND \| 0x01)
	35	#define TCS3472_WTIME (TCS3472_COMMAND \| 0x03)
	36	#define TCS3472_AILT (TCS3472_COMMAND \| 0x04)
	37	#define TCS3472_AIHT (TCS3472_COMMAND \| 0x06)
	38	#define TCS3472_PERS (TCS3472_COMMAND \| 0x0c)
	39	#define TCS3472_CONFIG (TCS3472_COMMAND \| 0x0d)
	40	#define TCS3472_CONTROL (TCS3472_COMMAND \| 0x0f)
	41	#define TCS3472_ID (TCS3472_COMMAND \| 0x12)
	42	#define TCS3472_STATUS (TCS3472_COMMAND \| 0x13)
	43	#define TCS3472_CDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x14)
	44	#define TCS3472_RDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x16)
	45	#define TCS3472_GDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x18)
	46	#define TCS3472_BDATA (TCS3472_COMMAND \| TCS3472_AUTO_INCR \| 0x1a)
	47
	48	#define TCS3472_STATUS_AVALID BIT(0)
	49	#define TCS3472_ENABLE_AEN BIT(1)
	50	#define TCS3472_ENABLE_PON BIT(0)
	51	#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) \| BIT(1))
	52
	53	struct tcs3472_data {
	54	struct i2c_client *client;
	55	u8 enable;
	56	u8 control;
	57	u8 atime;
6a2f39b7	58	u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
eb869ade PM	59	};
eb869ade PM	60
eb869ade PM	61	#define TCS3472_CHANNEL(_color, _si, _addr) { \
	62	.type = IIO_INTENSITY, \
	63	.modified = 1, \
	64	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	65	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) \| \
	66	BIT(IIO_CHAN_INFO_INT_TIME), \
	67	.channel2 = IIO_MOD_LIGHT_##_color, \
	68	.address = _addr, \
	69	.scan_index = _si, \
6b25f6e6 JC	70	.scan_type = { \
	71	.sign = 'u', \
	72	.realbits = 16, \
	73	.storagebits = 16, \
	74	.endianness = IIO_CPU, \
	75	}, \
eb869ade PM	76	}
	77
	78	static const int tcs3472_agains[] = { 1, 4, 16, 60 };
	79
	80	static const struct iio_chan_spec tcs3472_channels[] = {
	81	TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA),
	82	TCS3472_CHANNEL(RED, 1, TCS3472_RDATA),
	83	TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA),
	84	TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA),
	85	IIO_CHAN_SOFT_TIMESTAMP(4),
	86	};
	87
	88	static int tcs3472_req_data(struct tcs3472_data *data)
	89	{
	90	int tries = 50;
	91	int ret;
	92
	93	while (tries--) {
	94	ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
	95	if (ret < 0)
	96	return ret;
	97	if (ret & TCS3472_STATUS_AVALID)
	98	break;
	99	msleep(20);
	100	}
	101
	102	if (tries < 0) {
	103	dev_err(&data->client->dev, "data not ready\n");
	104	return -EIO;
	105	}
	106
	107	return 0;
	108	}
	109
	110	static int tcs3472_read_raw(struct iio_dev *indio_dev,
	111	struct iio_chan_spec const *chan,
	112	int val, int val2, long mask)
	113	{
	114	struct tcs3472_data *data = iio_priv(indio_dev);
	115	int ret;
	116
	117	switch (mask) {
	118	case IIO_CHAN_INFO_RAW:
95bd363b AS	119	ret = iio_device_claim_direct_mode(indio_dev);
	120	if (ret)
	121	return ret;
eb869ade	122	ret = tcs3472_req_data(data);
2a58b4f8	123	if (ret < 0) {
95bd363b	124	iio_device_release_direct_mode(indio_dev);
eb869ade	125	return ret;
2a58b4f8	126	}
eb869ade	127	ret = i2c_smbus_read_word_data(data->client, chan->address);
95bd363b	128	iio_device_release_direct_mode(indio_dev);
eb869ade PM	129	if (ret < 0)
	130	return ret;
	131	*val = ret;
	132	return IIO_VAL_INT;
	133	case IIO_CHAN_INFO_CALIBSCALE:
	134	*val = tcs3472_agains[data->control &
	135	TCS3472_CONTROL_AGAIN_MASK];
	136	return IIO_VAL_INT;
	137	case IIO_CHAN_INFO_INT_TIME:
	138	*val = 0;
	139	val2 = (256 - data->atime) 2400;
	140	return IIO_VAL_INT_PLUS_MICRO;
	141	}
	142	return -EINVAL;
	143	}
	144
	145	static int tcs3472_write_raw(struct iio_dev *indio_dev,
	146	struct iio_chan_spec const *chan,
	147	int val, int val2, long mask)
	148	{
	149	struct tcs3472_data *data = iio_priv(indio_dev);
	150	int i;
	151
	152	switch (mask) {
	153	case IIO_CHAN_INFO_CALIBSCALE:
	154	if (val2 != 0)
	155	return -EINVAL;
	156	for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) {
	157	if (val == tcs3472_agains[i]) {
	158	data->control &= ~TCS3472_CONTROL_AGAIN_MASK;
	159	data->control \|= i;
	160	return i2c_smbus_write_byte_data(
	161	data->client, TCS3472_CONTROL,
	162	data->control);
	163	}
	164	}
	165	return -EINVAL;
	166	case IIO_CHAN_INFO_INT_TIME:
	167	if (val != 0)
	168	return -EINVAL;
	169	for (i = 0; i < 256; i++) {
	170	if (val2 == (256 - i) * 2400) {
	171	data->atime = i;
	172	return i2c_smbus_write_word_data(
	173	data->client, TCS3472_ATIME,
	174	data->atime);
	175	}
	176
	177	}
	178	return -EINVAL;
	179	}
	180	return -EINVAL;
	181	}
	182
	183	static irqreturn_t tcs3472_trigger_handler(int irq, void *p)
	184	{
	185	struct iio_poll_func *pf = p;
	186	struct iio_dev *indio_dev = pf->indio_dev;
	187	struct tcs3472_data *data = iio_priv(indio_dev);
eb869ade PM	188	int i, j = 0;
	189
	190	int ret = tcs3472_req_data(data);
	191	if (ret < 0)
	192	goto done;
	193
	194	for_each_set_bit(i, indio_dev->active_scan_mask,
	195	indio_dev->masklength) {
	196	ret = i2c_smbus_read_word_data(data->client,
	197	TCS3472_CDATA + 2*i);
	198	if (ret < 0)
	199	goto done;
	200
	201	data->buffer[j++] = ret;
eb869ade PM	202	}
eb869ade PM	203
0624bf84	204	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
bc2b7dab	205	iio_get_time_ns(indio_dev));
eb869ade PM	206
	207	done:
	208	iio_trigger_notify_done(indio_dev->trig);
	209
	210	return IRQ_HANDLED;
	211	}
	212
	213	static ssize_t tcs3472_show_int_time_available(struct device *dev,
	214	struct device_attribute *attr,
	215	char *buf)
	216	{
	217	size_t len = 0;
	218	int i;
	219
	220	for (i = 1; i <= 256; i++)
	221	len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",
	222	2400 * i);
	223
	224	/* replace trailing space by newline */
	225	buf[len - 1] = '\n';
	226
	227	return len;
	228	}
	229
	230	static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");
	231	static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);
	232
	233	static struct attribute *tcs3472_attributes[] = {
	234	&iio_const_attr_calibscale_available.dev_attr.attr,
	235	&iio_dev_attr_integration_time_available.dev_attr.attr,
	236	NULL
	237	};
	238
	239	static const struct attribute_group tcs3472_attribute_group = {
	240	.attrs = tcs3472_attributes,
	241	};
	242
	243	static const struct iio_info tcs3472_info = {
	244	.read_raw = tcs3472_read_raw,
	245	.write_raw = tcs3472_write_raw,
	246	.attrs = &tcs3472_attribute_group,
	247	.driver_module = THIS_MODULE,
	248	};
	249
	250	static int tcs3472_probe(struct i2c_client *client,
	251	const struct i2c_device_id *id)
	252	{
	253	struct tcs3472_data *data;
	254	struct iio_dev *indio_dev;
	255	int ret;
	256
	257	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	258	if (indio_dev == NULL)
	259	return -ENOMEM;
	260
	261	data = iio_priv(indio_dev);
	262	i2c_set_clientdata(client, indio_dev);
	263	data->client = client;
	264
	265	indio_dev->dev.parent = &client->dev;
	266	indio_dev->info = &tcs3472_info;
	267	indio_dev->name = TCS3472_DRV_NAME;
	268	indio_dev->channels = tcs3472_channels;
	269	indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);
270	indio_dev->modes = INDIO_DIRECT_MODE;
271
272	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);
273	if (ret < 0)
274	return ret;
275
276	if (ret == 0x44)
277	dev_info(&client->dev, "TCS34721/34725 found\n");
278	else if (ret == 0x4d)
279	dev_info(&client->dev, "TCS34723/34727 found\n");
280	else
281	return -ENODEV;
282
283	ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);
284	if (ret < 0)
285	return ret;
286	data->control = ret;
287
288	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);
289	if (ret < 0)
290	return ret;
291	data->atime = ret;
292
293	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
294	if (ret < 0)
295	return ret;
296
297	/* enable device */
298	data->enable = ret \| TCS3472_ENABLE_PON \| TCS3472_ENABLE_AEN;
299	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
300	data->enable);
301	if (ret < 0)
302	return ret;
303
304	ret = iio_triggered_buffer_setup(indio_dev, NULL,
305	tcs3472_trigger_handler, NULL);
306	if (ret < 0)
307	return ret;
308
309	ret = iio_device_register(indio_dev);
310	if (ret < 0)
311	goto buffer_cleanup;
312
313	return 0;
314
315	buffer_cleanup:
316	iio_triggered_buffer_cleanup(indio_dev);
317	return ret;
318	}
319
320	static int tcs3472_powerdown(struct tcs3472_data *data)
321	{
322	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
323	data->enable & ~(TCS3472_ENABLE_AEN \| TCS3472_ENABLE_PON));
324	}
325
326	static int tcs3472_remove(struct i2c_client *client)
327	{
328	struct iio_dev *indio_dev = i2c_get_clientdata(client);
329
330	iio_device_unregister(indio_dev);
331	iio_triggered_buffer_cleanup(indio_dev);
332	tcs3472_powerdown(iio_priv(indio_dev));
333
334	return 0;
335	}
336
337	#ifdef CONFIG_PM_SLEEP
338	static int tcs3472_suspend(struct device *dev)
339	{
4caf279a PM	340	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
	341	to_i2c_client(dev)));
	342	return tcs3472_powerdown(data);
eb869ade PM	343	}
	344
	345	static int tcs3472_resume(struct device *dev)
	346	{
4caf279a PM	347	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
4caf279a PM	348	to_i2c_client(dev)));
eb869ade PM	349	return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
	350	data->enable \| (TCS3472_ENABLE_AEN \| TCS3472_ENABLE_PON));
	351	}
	352	#endif
	353
	354	static SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, tcs3472_resume);
	355
	356	static const struct i2c_device_id tcs3472_id[] = {
	357	{ "tcs3472", 0 },
	358	{ }
	359	};
	360	MODULE_DEVICE_TABLE(i2c, tcs3472_id);
	361
	362	static struct i2c_driver tcs3472_driver = {
	363	.driver = {
	364	.name = TCS3472_DRV_NAME,
	365	.pm = &tcs3472_pm_ops,
eb869ade PM	366	},
	367	.probe = tcs3472_probe,
	368	.remove = tcs3472_remove,
	369	.id_table = tcs3472_id,
	370	};
	371	module_i2c_driver(tcs3472_driver);
	372
	373	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
	374	MODULE_DESCRIPTION("TCS3472 color light sensors driver");
	375	MODULE_LICENSE("GPL");