1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter
4 *
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.pdf
12 *
13 * TODO: wait time
14 */
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
58 struct 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
74 static 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
110 static const int tcs3472_agains[] = { 1, 4, 16, 60 };
111
112 static 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
tcs3472_req_data(struct tcs3472_data * data)120 static 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
tcs3472_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)142 static 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
tcs3472_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)177 static 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-range
217 * clear channel values before an interrupt is generated
218 */
219 static const int tcs3472_intr_pers[] = {
220 0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
221 };
222
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)223 static 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
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)257 static 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 else
289 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 }
308 error:
309 mutex_unlock(&data->lock);
310
311 return ret;
312 }
313
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)314 static 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
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)328 static 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 else
343 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
tcs3472_event_handler(int irq,void * priv)356 static 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
tcs3472_trigger_handler(int irq,void * p)375 static 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 for_each_set_bit(i, indio_dev->active_scan_mask,
387 indio_dev->masklength) {
388 ret = i2c_smbus_read_word_data(data->client,
389 TCS3472_CDATA + 2*i);
390 if (ret < 0)
391 goto done;
392
393 data->scan.chans[j++] = ret;
394 }
395
396 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
397 iio_get_time_ns(indio_dev));
398
399 done:
400 iio_trigger_notify_done(indio_dev->trig);
401
402 return IRQ_HANDLED;
403 }
404
tcs3472_show_int_time_available(struct device * dev,struct device_attribute * attr,char * buf)405 static ssize_t tcs3472_show_int_time_available(struct device *dev,
406 struct device_attribute *attr,
407 char *buf)
408 {
409 size_t len = 0;
410 int i;
411
412 for (i = 1; i <= 256; i++)
413 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",
414 2400 * i);
415
416 /* replace trailing space by newline */
417 buf[len - 1] = '\n';
418
419 return len;
420 }
421
422 static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");
423 static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);
424
425 static struct attribute *tcs3472_attributes[] = {
426 &iio_const_attr_calibscale_available.dev_attr.attr,
427 &iio_dev_attr_integration_time_available.dev_attr.attr,
428 NULL
429 };
430
431 static const struct attribute_group tcs3472_attribute_group = {
432 .attrs = tcs3472_attributes,
433 };
434
435 static const struct iio_info tcs3472_info = {
436 .read_raw = tcs3472_read_raw,
437 .write_raw = tcs3472_write_raw,
438 .read_event_value = tcs3472_read_event,
439 .write_event_value = tcs3472_write_event,
440 .read_event_config = tcs3472_read_event_config,
441 .write_event_config = tcs3472_write_event_config,
442 .attrs = &tcs3472_attribute_group,
443 };
444
tcs3472_probe(struct i2c_client * client)445 static int tcs3472_probe(struct i2c_client *client)
446 {
447 struct tcs3472_data *data;
448 struct iio_dev *indio_dev;
449 int ret;
450
451 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
452 if (indio_dev == NULL)
453 return -ENOMEM;
454
455 data = iio_priv(indio_dev);
456 i2c_set_clientdata(client, indio_dev);
457 data->client = client;
458 mutex_init(&data->lock);
459
460 indio_dev->info = &tcs3472_info;
461 indio_dev->name = TCS3472_DRV_NAME;
462 indio_dev->channels = tcs3472_channels;
463 indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);
464 indio_dev->modes = INDIO_DIRECT_MODE;
465
466 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);
467 if (ret < 0)
468 return ret;
469
470 if (ret == 0x44)
471 dev_info(&client->dev, "TCS34721/34725 found\n");
472 else if (ret == 0x4d)
473 dev_info(&client->dev, "TCS34723/34727 found\n");
474 else
475 return -ENODEV;
476
477 ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);
478 if (ret < 0)
479 return ret;
480 data->control = ret;
481
482 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);
483 if (ret < 0)
484 return ret;
485 data->atime = ret;
486
487 ret = i2c_smbus_read_word_data(data->client, TCS3472_AILT);
488 if (ret < 0)
489 return ret;
490 data->low_thresh = ret;
491
492 ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT);
493 if (ret < 0)
494 return ret;
495 data->high_thresh = ret;
496
497 data->apers = 1;
498 ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS,
499 data->apers);
500 if (ret < 0)
501 return ret;
502
503 ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
504 if (ret < 0)
505 return ret;
506
507 /* enable device */
508 data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN;
509 data->enable &= ~TCS3472_ENABLE_AIEN;
510 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
511 data->enable);
512 if (ret < 0)
513 return ret;
514
515 ret = iio_triggered_buffer_setup(indio_dev, NULL,
516 tcs3472_trigger_handler, NULL);
517 if (ret < 0)
518 return ret;
519
520 if (client->irq) {
521 ret = request_threaded_irq(client->irq, NULL,
522 tcs3472_event_handler,
523 IRQF_TRIGGER_FALLING | IRQF_SHARED |
524 IRQF_ONESHOT,
525 client->name, indio_dev);
526 if (ret)
527 goto buffer_cleanup;
528 }
529
530 ret = iio_device_register(indio_dev);
531 if (ret < 0)
532 goto free_irq;
533
534 return 0;
535
536 free_irq:
537 if (client->irq)
538 free_irq(client->irq, indio_dev);
539 buffer_cleanup:
540 iio_triggered_buffer_cleanup(indio_dev);
541 return ret;
542 }
543
tcs3472_powerdown(struct tcs3472_data * data)544 static int tcs3472_powerdown(struct tcs3472_data *data)
545 {
546 int ret;
547 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
548
549 mutex_lock(&data->lock);
550
551 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
552 data->enable & ~enable_mask);
553 if (!ret)
554 data->enable &= ~enable_mask;
555
556 mutex_unlock(&data->lock);
557
558 return ret;
559 }
560
tcs3472_remove(struct i2c_client * client)561 static void tcs3472_remove(struct i2c_client *client)
562 {
563 struct iio_dev *indio_dev = i2c_get_clientdata(client);
564
565 iio_device_unregister(indio_dev);
566 if (client->irq)
567 free_irq(client->irq, indio_dev);
568 iio_triggered_buffer_cleanup(indio_dev);
569 tcs3472_powerdown(iio_priv(indio_dev));
570 }
571
tcs3472_suspend(struct device * dev)572 static int tcs3472_suspend(struct device *dev)
573 {
574 struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
575 to_i2c_client(dev)));
576 return tcs3472_powerdown(data);
577 }
578
tcs3472_resume(struct device * dev)579 static int tcs3472_resume(struct device *dev)
580 {
581 struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
582 to_i2c_client(dev)));
583 int ret;
584 u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
585
586 mutex_lock(&data->lock);
587
588 ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
589 data->enable | enable_mask);
590 if (!ret)
591 data->enable |= enable_mask;
592
593 mutex_unlock(&data->lock);
594
595 return ret;
596 }
597
598 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend,
599 tcs3472_resume);
600
601 static const struct i2c_device_id tcs3472_id[] = {
602 { "tcs3472", 0 },
603 { }
604 };
605 MODULE_DEVICE_TABLE(i2c, tcs3472_id);
606
607 static struct i2c_driver tcs3472_driver = {
608 .driver = {
609 .name = TCS3472_DRV_NAME,
610 .pm = pm_sleep_ptr(&tcs3472_pm_ops),
611 },
612 .probe = tcs3472_probe,
613 .remove = tcs3472_remove,
614 .id_table = tcs3472_id,
615 };
616 module_i2c_driver(tcs3472_driver);
617
618 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
619 MODULE_DESCRIPTION("TCS3472 color light sensors driver");
620 MODULE_LICENSE("GPL");
621
