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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter4 *5 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>6 *7 * Color light sensor with 16-bit channels for red, green, blue, clear);8 * 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725,9 * TCS34727)10 *11 * Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf12 *13 * TODO: wait time14 */15 16#include <linux/module.h>17#include <linux/i2c.h>18#include <linux/delay.h>19#include <linux/pm.h>20 21#include <linux/iio/iio.h>22#include <linux/iio/sysfs.h>23#include <linux/iio/events.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#define TCS3472_SPECIAL_FUNC (BIT(5) | BIT(6))33 34#define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06)35 36#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)37#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)38#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)39#define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04)40#define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x06)41#define TCS3472_PERS (TCS3472_COMMAND | 0x0c)42#define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d)43#define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f)44#define TCS3472_ID (TCS3472_COMMAND | 0x12)45#define TCS3472_STATUS (TCS3472_COMMAND | 0x13)46#define TCS3472_CDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x14)47#define TCS3472_RDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x16)48#define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18)49#define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a)50 51#define TCS3472_STATUS_AINT BIT(4)52#define TCS3472_STATUS_AVALID BIT(0)53#define TCS3472_ENABLE_AIEN BIT(4)54#define TCS3472_ENABLE_AEN BIT(1)55#define TCS3472_ENABLE_PON BIT(0)56#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1))57 58struct tcs3472_data {59	struct i2c_client *client;60	struct mutex lock;61	u16 low_thresh;62	u16 high_thresh;63	u8 enable;64	u8 control;65	u8 atime;66	u8 apers;67	/* Ensure timestamp is naturally aligned */68	struct {69		u16 chans[4];70		s64 timestamp __aligned(8);71	} scan;72};73 74static const struct iio_event_spec tcs3472_events[] = {75	{76		.type = IIO_EV_TYPE_THRESH,77		.dir = IIO_EV_DIR_RISING,78		.mask_separate = BIT(IIO_EV_INFO_VALUE),79	}, {80		.type = IIO_EV_TYPE_THRESH,81		.dir = IIO_EV_DIR_FALLING,82		.mask_separate = BIT(IIO_EV_INFO_VALUE),83	}, {84		.type = IIO_EV_TYPE_THRESH,85		.dir = IIO_EV_DIR_EITHER,86		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |87				 BIT(IIO_EV_INFO_PERIOD),88	},89};90 91#define TCS3472_CHANNEL(_color, _si, _addr) { \92	.type = IIO_INTENSITY, \93	.modified = 1, \94	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \95	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) | \96		BIT(IIO_CHAN_INFO_INT_TIME), \97	.channel2 = IIO_MOD_LIGHT_##_color, \98	.address = _addr, \99	.scan_index = _si, \100	.scan_type = { \101		.sign = 'u', \102		.realbits = 16, \103		.storagebits = 16, \104		.endianness = IIO_CPU, \105	}, \106	.event_spec = _si ? NULL : tcs3472_events, \107	.num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \108}109 110static const int tcs3472_agains[] = { 1, 4, 16, 60 };111 112static const struct iio_chan_spec tcs3472_channels[] = {113	TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA),114	TCS3472_CHANNEL(RED, 1, TCS3472_RDATA),115	TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA),116	TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA),117	IIO_CHAN_SOFT_TIMESTAMP(4),118};119 120static int tcs3472_req_data(struct tcs3472_data *data)121{122	int tries = 50;123	int ret;124 125	while (tries--) {126		ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);127		if (ret < 0)128			return ret;129		if (ret & TCS3472_STATUS_AVALID)130			break;131		msleep(20);132	}133 134	if (tries < 0) {135		dev_err(&data->client->dev, "data not ready\n");136		return -EIO;137	}138 139	return 0;140}141 142static int tcs3472_read_raw(struct iio_dev *indio_dev,143			   struct iio_chan_spec const *chan,144			   int *val, int *val2, long mask)145{146	struct tcs3472_data *data = iio_priv(indio_dev);147	int ret;148 149	switch (mask) {150	case IIO_CHAN_INFO_RAW:151		ret = iio_device_claim_direct_mode(indio_dev);152		if (ret)153			return ret;154		ret = tcs3472_req_data(data);155		if (ret < 0) {156			iio_device_release_direct_mode(indio_dev);157			return ret;158		}159		ret = i2c_smbus_read_word_data(data->client, chan->address);160		iio_device_release_direct_mode(indio_dev);161		if (ret < 0)162			return ret;163		*val = ret;164		return IIO_VAL_INT;165	case IIO_CHAN_INFO_CALIBSCALE:166		*val = tcs3472_agains[data->control &167			TCS3472_CONTROL_AGAIN_MASK];168		return IIO_VAL_INT;169	case IIO_CHAN_INFO_INT_TIME:170		*val = 0;171		*val2 = (256 - data->atime) * 2400;172		return IIO_VAL_INT_PLUS_MICRO;173	}174	return -EINVAL;175}176 177static int tcs3472_write_raw(struct iio_dev *indio_dev,178			       struct iio_chan_spec const *chan,179			       int val, int val2, long mask)180{181	struct tcs3472_data *data = iio_priv(indio_dev);182	int i;183 184	switch (mask) {185	case IIO_CHAN_INFO_CALIBSCALE:186		if (val2 != 0)187			return -EINVAL;188		for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) {189			if (val == tcs3472_agains[i]) {190				data->control &= ~TCS3472_CONTROL_AGAIN_MASK;191				data->control |= i;192				return i2c_smbus_write_byte_data(193					data->client, TCS3472_CONTROL,194					data->control);195			}196		}197		return -EINVAL;198	case IIO_CHAN_INFO_INT_TIME:199		if (val != 0)200			return -EINVAL;201		for (i = 0; i < 256; i++) {202			if (val2 == (256 - i) * 2400) {203				data->atime = i;204				return i2c_smbus_write_byte_data(205					data->client, TCS3472_ATIME,206					data->atime);207			}208 209		}210		return -EINVAL;211	}212	return -EINVAL;213}214 215/*216 * Translation from APERS field value to the number of consecutive out-of-range217 * clear channel values before an interrupt is generated218 */219static const int tcs3472_intr_pers[] = {220	0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60221};222 223static int tcs3472_read_event(struct iio_dev *indio_dev,224	const struct iio_chan_spec *chan, enum iio_event_type type,225	enum iio_event_direction dir, enum iio_event_info info, int *val,226	int *val2)227{228	struct tcs3472_data *data = iio_priv(indio_dev);229	int ret;230	unsigned int period;231 232	mutex_lock(&data->lock);233 234	switch (info) {235	case IIO_EV_INFO_VALUE:236		*val = (dir == IIO_EV_DIR_RISING) ?237			data->high_thresh : data->low_thresh;238		ret = IIO_VAL_INT;239		break;240	case IIO_EV_INFO_PERIOD:241		period = (256 - data->atime) * 2400 *242			tcs3472_intr_pers[data->apers];243		*val = period / USEC_PER_SEC;244		*val2 = period % USEC_PER_SEC;245		ret = IIO_VAL_INT_PLUS_MICRO;246		break;247	default:248		ret = -EINVAL;249		break;250	}251 252	mutex_unlock(&data->lock);253 254	return ret;255}256 257static int tcs3472_write_event(struct iio_dev *indio_dev,258	const struct iio_chan_spec *chan, enum iio_event_type type,259	enum iio_event_direction dir, enum iio_event_info info, int val,260	int val2)261{262	struct tcs3472_data *data = iio_priv(indio_dev);263	int ret;264	u8 command;265	int period;266	int i;267 268	mutex_lock(&data->lock);269	switch (info) {270	case IIO_EV_INFO_VALUE:271		switch (dir) {272		case IIO_EV_DIR_RISING:273			command = TCS3472_AIHT;274			break;275		case IIO_EV_DIR_FALLING:276			command = TCS3472_AILT;277			break;278		default:279			ret = -EINVAL;280			goto error;281		}282		ret = i2c_smbus_write_word_data(data->client, command, val);283		if (ret)284			goto error;285 286		if (dir == IIO_EV_DIR_RISING)287			data->high_thresh = val;288		else289			data->low_thresh = val;290		break;291	case IIO_EV_INFO_PERIOD:292		period = val * USEC_PER_SEC + val2;293		for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) {294			if (period <= (256 - data->atime) * 2400 *295					tcs3472_intr_pers[i])296				break;297		}298		ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i);299		if (ret)300			goto error;301 302		data->apers = i;303		break;304	default:305		ret = -EINVAL;306		break;307	}308error:309	mutex_unlock(&data->lock);310 311	return ret;312}313 314static int tcs3472_read_event_config(struct iio_dev *indio_dev,315	const struct iio_chan_spec *chan, enum iio_event_type type,316	enum iio_event_direction dir)317{318	struct tcs3472_data *data = iio_priv(indio_dev);319	int ret;320 321	mutex_lock(&data->lock);322	ret = !!(data->enable & TCS3472_ENABLE_AIEN);323	mutex_unlock(&data->lock);324 325	return ret;326}327 328static int tcs3472_write_event_config(struct iio_dev *indio_dev,329	const struct iio_chan_spec *chan, enum iio_event_type type,330	enum iio_event_direction dir, int state)331{332	struct tcs3472_data *data = iio_priv(indio_dev);333	int ret = 0;334	u8 enable_old;335 336	mutex_lock(&data->lock);337 338	enable_old = data->enable;339 340	if (state)341		data->enable |= TCS3472_ENABLE_AIEN;342	else343		data->enable &= ~TCS3472_ENABLE_AIEN;344 345	if (enable_old != data->enable) {346		ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,347						data->enable);348		if (ret)349			data->enable = enable_old;350	}351	mutex_unlock(&data->lock);352 353	return ret;354}355 356static irqreturn_t tcs3472_event_handler(int irq, void *priv)357{358	struct iio_dev *indio_dev = priv;359	struct tcs3472_data *data = iio_priv(indio_dev);360	int ret;361 362	ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);363	if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) {364		iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,365						IIO_EV_TYPE_THRESH,366						IIO_EV_DIR_EITHER),367				iio_get_time_ns(indio_dev));368 369		i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR);370	}371 372	return IRQ_HANDLED;373}374 375static irqreturn_t tcs3472_trigger_handler(int irq, void *p)376{377	struct iio_poll_func *pf = p;378	struct iio_dev *indio_dev = pf->indio_dev;379	struct tcs3472_data *data = iio_priv(indio_dev);380	int i, j = 0;381 382	int ret = tcs3472_req_data(data);383	if (ret < 0)384		goto done;385 386	iio_for_each_active_channel(indio_dev, i) {387		ret = i2c_smbus_read_word_data(data->client,388			TCS3472_CDATA + 2*i);389		if (ret < 0)390			goto done;391 392		data->scan.chans[j++] = ret;393	}394 395	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,396		iio_get_time_ns(indio_dev));397 398done:399	iio_trigger_notify_done(indio_dev->trig);400 401	return IRQ_HANDLED;402}403 404static ssize_t tcs3472_show_int_time_available(struct device *dev,405					struct device_attribute *attr,406					char *buf)407{408	size_t len = 0;409	int i;410 411	for (i = 1; i <= 256; i++)412		len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",413			2400 * i);414 415	/* replace trailing space by newline */416	buf[len - 1] = '\n';417 418	return len;419}420 421static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");422static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);423 424static struct attribute *tcs3472_attributes[] = {425	&iio_const_attr_calibscale_available.dev_attr.attr,426	&iio_dev_attr_integration_time_available.dev_attr.attr,427	NULL428};429 430static const struct attribute_group tcs3472_attribute_group = {431	.attrs = tcs3472_attributes,432};433 434static const struct iio_info tcs3472_info = {435	.read_raw = tcs3472_read_raw,436	.write_raw = tcs3472_write_raw,437	.read_event_value = tcs3472_read_event,438	.write_event_value = tcs3472_write_event,439	.read_event_config = tcs3472_read_event_config,440	.write_event_config = tcs3472_write_event_config,441	.attrs = &tcs3472_attribute_group,442};443 444static int tcs3472_probe(struct i2c_client *client)445{446	struct tcs3472_data *data;447	struct iio_dev *indio_dev;448	int ret;449 450	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));451	if (indio_dev == NULL)452		return -ENOMEM;453 454	data = iio_priv(indio_dev);455	i2c_set_clientdata(client, indio_dev);456	data->client = client;457	mutex_init(&data->lock);458 459	indio_dev->info = &tcs3472_info;460	indio_dev->name = TCS3472_DRV_NAME;461	indio_dev->channels = tcs3472_channels;462	indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);463	indio_dev->modes = INDIO_DIRECT_MODE;464 465	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);466	if (ret < 0)467		return ret;468 469	if (ret == 0x44)470		dev_info(&client->dev, "TCS34721/34725 found\n");471	else if (ret == 0x4d)472		dev_info(&client->dev, "TCS34723/34727 found\n");473	else474		return -ENODEV;475 476	ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);477	if (ret < 0)478		return ret;479	data->control = ret;480 481	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);482	if (ret < 0)483		return ret;484	data->atime = ret;485 486	ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT);487	if (ret < 0)488		return ret;489	data->low_thresh = ret;490 491	ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT);492	if (ret < 0)493		return ret;494	data->high_thresh = ret;495 496	data->apers = 1;497	ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS,498					data->apers);499	if (ret < 0)500		return ret;501 502	ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);503	if (ret < 0)504		return ret;505 506	/* enable device */507	data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN;508	data->enable &= ~TCS3472_ENABLE_AIEN;509	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,510		data->enable);511	if (ret < 0)512		return ret;513 514	ret = iio_triggered_buffer_setup(indio_dev, NULL,515		tcs3472_trigger_handler, NULL);516	if (ret < 0)517		return ret;518 519	if (client->irq) {520		ret = request_threaded_irq(client->irq, NULL,521					   tcs3472_event_handler,522					   IRQF_TRIGGER_FALLING | IRQF_SHARED |523					   IRQF_ONESHOT,524					   client->name, indio_dev);525		if (ret)526			goto buffer_cleanup;527	}528 529	ret = iio_device_register(indio_dev);530	if (ret < 0)531		goto free_irq;532 533	return 0;534 535free_irq:536	if (client->irq)537		free_irq(client->irq, indio_dev);538buffer_cleanup:539	iio_triggered_buffer_cleanup(indio_dev);540	return ret;541}542 543static int tcs3472_powerdown(struct tcs3472_data *data)544{545	int ret;546	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;547 548	mutex_lock(&data->lock);549 550	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,551		data->enable & ~enable_mask);552	if (!ret)553		data->enable &= ~enable_mask;554 555	mutex_unlock(&data->lock);556 557	return ret;558}559 560static void tcs3472_remove(struct i2c_client *client)561{562	struct iio_dev *indio_dev = i2c_get_clientdata(client);563 564	iio_device_unregister(indio_dev);565	if (client->irq)566		free_irq(client->irq, indio_dev);567	iio_triggered_buffer_cleanup(indio_dev);568	tcs3472_powerdown(iio_priv(indio_dev));569}570 571static int tcs3472_suspend(struct device *dev)572{573	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(574		to_i2c_client(dev)));575	return tcs3472_powerdown(data);576}577 578static int tcs3472_resume(struct device *dev)579{580	struct tcs3472_data *data = iio_priv(i2c_get_clientdata(581		to_i2c_client(dev)));582	int ret;583	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;584 585	mutex_lock(&data->lock);586 587	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,588		data->enable | enable_mask);589	if (!ret)590		data->enable |= enable_mask;591 592	mutex_unlock(&data->lock);593 594	return ret;595}596 597static DEFINE_SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend,598				tcs3472_resume);599 600static const struct i2c_device_id tcs3472_id[] = {601	{ "tcs3472" },602	{ }603};604MODULE_DEVICE_TABLE(i2c, tcs3472_id);605 606static struct i2c_driver tcs3472_driver = {607	.driver = {608		.name	= TCS3472_DRV_NAME,609		.pm	= pm_sleep_ptr(&tcs3472_pm_ops),610	},611	.probe		= tcs3472_probe,612	.remove		= tcs3472_remove,613	.id_table	= tcs3472_id,614};615module_i2c_driver(tcs3472_driver);616 617MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");618MODULE_DESCRIPTION("TCS3472 color light sensors driver");619MODULE_LICENSE("GPL");620