aboutsummaryrefslogtreecommitdiff
path: root/drivers/iio/light/tcs3472.c
blob: 12ad344410103c502c86cdb64a709a2c02860d04 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
// SPDX-License-Identifier: GPL-2.0-only
/*
 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter
 *
 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * 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: 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/events.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_SPECIAL_FUNC (BIT(5) | BIT(6))

#define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06)

#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)
#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)
#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)
#define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04)
#define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 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_AINT BIT(4)
#define TCS3472_STATUS_AVALID BIT(0)
#define TCS3472_ENABLE_AIEN BIT(4)
#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;
	struct mutex lock;
	u16 low_thresh;
	u16 high_thresh;
	u8 enable;
	u8 control;
	u8 atime;
	u8 apers;
	u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
};

static const struct iio_event_spec tcs3472_events[] = {
	{
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_RISING,
		.mask_separate = BIT(IIO_EV_INFO_VALUE),
	}, {
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_FALLING,
		.mask_separate = BIT(IIO_EV_INFO_VALUE),
	}, {
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_EITHER,
		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
				 BIT(IIO_EV_INFO_PERIOD),
	},
};

#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, \
	}, \
	.event_spec = _si ? NULL : tcs3472_events, \
	.num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \
}

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;
}

/*
 * Translation from APERS field value to the number of consecutive out-of-range
 * clear channel values before an interrupt is generated
 */
static const int tcs3472_intr_pers[] = {
	0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
};

static int tcs3472_read_event(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, enum iio_event_info info, int *val,
	int *val2)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret;
	unsigned int period;

	mutex_lock(&data->lock);

	switch (info) {
	case IIO_EV_INFO_VALUE:
		*val = (dir == IIO_EV_DIR_RISING) ?
			data->high_thresh : data->low_thresh;
		ret = IIO_VAL_INT;
		break;
	case IIO_EV_INFO_PERIOD:
		period = (256 - data->atime) * 2400 *
			tcs3472_intr_pers[data->apers];
		*val = period / USEC_PER_SEC;
		*val2 = period % USEC_PER_SEC;
		ret = IIO_VAL_INT_PLUS_MICRO;
		break;
	default:
		ret = -EINVAL;
		break;
	}

	mutex_unlock(&data->lock);

	return ret;
}

static int tcs3472_write_event(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, enum iio_event_info info, int val,
	int val2)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret;
	u8 command;
	int period;
	int i;

	mutex_lock(&data->lock);
	switch (info) {
	case IIO_EV_INFO_VALUE:
		switch (dir) {
		case IIO_EV_DIR_RISING:
			command = TCS3472_AIHT;
			break;
		case IIO_EV_DIR_FALLING:
			command = TCS3472_AILT;
			break;
		default:
			ret = -EINVAL;
			goto error;
		}
		ret = i2c_smbus_write_word_data(data->client, command, val);
		if (ret)
			goto error;

		if (dir == IIO_EV_DIR_RISING)
			data->high_thresh = val;
		else
			data->low_thresh = val;
		break;
	case IIO_EV_INFO_PERIOD:
		period = val * USEC_PER_SEC + val2;
		for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) {
			if (period <= (256 - data->atime) * 2400 *
					tcs3472_intr_pers[i])
				break;
		}
		ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i);
		if (ret)
			goto error;

		data->apers = i;
		break;
	default:
		ret = -EINVAL;
		break;
	}
error:
	mutex_unlock(&data->lock);

	return ret;
}

static int tcs3472_read_event_config(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret;

	mutex_lock(&data->lock);
	ret = !!(data->enable & TCS3472_ENABLE_AIEN);
	mutex_unlock(&data->lock);

	return ret;
}

static int tcs3472_write_event_config(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, int state)
{
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret = 0;
	u8 enable_old;

	mutex_lock(&data->lock);

	enable_old = data->enable;

	if (state)
		data->enable |= TCS3472_ENABLE_AIEN;
	else
		data->enable &= ~TCS3472_ENABLE_AIEN;

	if (enable_old != data->enable) {
		ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
						data->enable);
		if (ret)
			data->enable = enable_old;
	}
	mutex_unlock(&data->lock);

	return ret;
}

static irqreturn_t tcs3472_event_handler(int irq, void *priv)
{
	struct iio_dev *indio_dev = priv;
	struct tcs3472_data *data = iio_priv(indio_dev);
	int ret;

	ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
	if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) {
		iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
						IIO_EV_TYPE_THRESH,
						IIO_EV_DIR_EITHER),
				iio_get_time_ns(indio_dev));

		i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR);
	}

	return IRQ_HANDLED;
}

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,
	.read_event_value = tcs3472_read_event,
	.write_event_value = tcs3472_write_event,
	.read_event_config = tcs3472_read_event_config,
	.write_event_config = tcs3472_write_event_config,
	.attrs = &tcs3472_attribute_group,
};

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;
	mutex_init(&data->lock);

	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_word_data(data->client, TCS3472_AILT);
	if (ret < 0)
		return ret;
	data->low_thresh = ret;

	ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT);
	if (ret < 0)
		return ret;
	data->high_thresh = ret;

	data->apers = 1;
	ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS,
					data->apers);
	if (ret < 0)
		return 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;
	data->enable &= ~TCS3472_ENABLE_AIEN;
	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;

	if (client->irq) {
		ret = request_threaded_irq(client->irq, NULL,
					   tcs3472_event_handler,
					   IRQF_TRIGGER_FALLING | IRQF_SHARED |
					   IRQF_ONESHOT,
					   client->name, indio_dev);
		if (ret)
			goto buffer_cleanup;
	}

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

	return 0;

free_irq:
	free_irq(client->irq, indio_dev);
buffer_cleanup:
	iio_triggered_buffer_cleanup(indio_dev);
	return ret;
}

static int tcs3472_powerdown(struct tcs3472_data *data)
{
	int ret;
	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;

	mutex_lock(&data->lock);

	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
		data->enable & ~enable_mask);
	if (!ret)
		data->enable &= ~enable_mask;

	mutex_unlock(&data->lock);

	return ret;
}

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

	iio_device_unregister(indio_dev);
	free_irq(client->irq, 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)));
	int ret;
	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;

	mutex_lock(&data->lock);

	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
		data->enable | enable_mask);
	if (!ret)
		data->enable |= enable_mask;

	mutex_unlock(&data->lock);

	return ret;
}
#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");