1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * opt3001.c - Texas Instruments OPT3001 Light Sensor
4 *
5 * Copyright (C) 2014 Texas Instruments Incorporated - https://www.ti.com
6 *
7 * Author: Andreas Dannenberg <dannenberg@ti.com>
8 * Based on previous work from: Felipe Balbi <balbi@ti.com>
9 */
10
11 #include <linux/bitops.h>
12 #include <linux/delay.h>
13 #include <linux/device.h>
14 #include <linux/i2c.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/mutex.h>
21 #include <linux/slab.h>
22 #include <linux/types.h>
23
24 #include <linux/iio/events.h>
25 #include <linux/iio/iio.h>
26 #include <linux/iio/sysfs.h>
27
28 #define OPT3001_RESULT 0x00
29 #define OPT3001_CONFIGURATION 0x01
30 #define OPT3001_LOW_LIMIT 0x02
31 #define OPT3001_HIGH_LIMIT 0x03
32 #define OPT3001_MANUFACTURER_ID 0x7e
33 #define OPT3001_DEVICE_ID 0x7f
34
35 #define OPT3001_CONFIGURATION_RN_MASK (0xf << 12)
36 #define OPT3001_CONFIGURATION_RN_AUTO (0xc << 12)
37
38 #define OPT3001_CONFIGURATION_CT BIT(11)
39
40 #define OPT3001_CONFIGURATION_M_MASK (3 << 9)
41 #define OPT3001_CONFIGURATION_M_SHUTDOWN (0 << 9)
42 #define OPT3001_CONFIGURATION_M_SINGLE (1 << 9)
43 #define OPT3001_CONFIGURATION_M_CONTINUOUS (2 << 9) /* also 3 << 9 */
44
45 #define OPT3001_CONFIGURATION_OVF BIT(8)
46 #define OPT3001_CONFIGURATION_CRF BIT(7)
47 #define OPT3001_CONFIGURATION_FH BIT(6)
48 #define OPT3001_CONFIGURATION_FL BIT(5)
49 #define OPT3001_CONFIGURATION_L BIT(4)
50 #define OPT3001_CONFIGURATION_POL BIT(3)
51 #define OPT3001_CONFIGURATION_ME BIT(2)
52
53 #define OPT3001_CONFIGURATION_FC_MASK (3 << 0)
54
55 /* The end-of-conversion enable is located in the low-limit register */
56 #define OPT3001_LOW_LIMIT_EOC_ENABLE 0xc000
57
58 #define OPT3001_REG_EXPONENT(n) ((n) >> 12)
59 #define OPT3001_REG_MANTISSA(n) ((n) & 0xfff)
60
61 #define OPT3001_INT_TIME_LONG 800000
62 #define OPT3001_INT_TIME_SHORT 100000
63
64 /*
65 * Time to wait for conversion result to be ready. The device datasheet
66 * sect. 6.5 states results are ready after total integration time plus 3ms.
67 * This results in worst-case max values of 113ms or 883ms, respectively.
68 * Add some slack to be on the safe side.
69 */
70 #define OPT3001_RESULT_READY_SHORT 150
71 #define OPT3001_RESULT_READY_LONG 1000
72
73 struct opt3001_scale {
74 int val;
75 int val2;
76 };
77
78 struct opt3001_chip_info {
79 const struct iio_chan_spec (*channels)[2];
80 enum iio_chan_type chan_type;
81 int num_channels;
82
83 const struct opt3001_scale (*scales)[12];
84 /*
85 * Factor as specified by conversion equation in datasheet.
86 * eg. 0.01 (scaled to integer 10) for opt3001.
87 */
88 int factor_whole;
89 /*
90 * Factor to compensate for potentially scaled factor_whole.
91 */
92 int factor_integer;
93 /*
94 * Factor used to align decimal part of proccessed value to six decimal
95 * places.
96 */
97 int factor_decimal;
98
99 bool has_id;
100 };
101
102 struct opt3001 {
103 struct i2c_client *client;
104 struct device *dev;
105
106 struct mutex lock;
107 bool ok_to_ignore_lock;
108 bool result_ready;
109 wait_queue_head_t result_ready_queue;
110 u16 result;
111 const struct opt3001_chip_info *chip_info;
112
113 u32 int_time;
114 u32 mode;
115
116 u16 high_thresh_mantissa;
117 u16 low_thresh_mantissa;
118
119 u8 high_thresh_exp;
120 u8 low_thresh_exp;
121
122 bool use_irq;
123 };
124
125 static const struct opt3001_scale opt3001_scales[] = {
126 {
127 .val = 40,
128 .val2 = 950000,
129 },
130 {
131 .val = 81,
132 .val2 = 900000,
133 },
134 {
135 .val = 163,
136 .val2 = 800000,
137 },
138 {
139 .val = 327,
140 .val2 = 600000,
141 },
142 {
143 .val = 655,
144 .val2 = 200000,
145 },
146 {
147 .val = 1310,
148 .val2 = 400000,
149 },
150 {
151 .val = 2620,
152 .val2 = 800000,
153 },
154 {
155 .val = 5241,
156 .val2 = 600000,
157 },
158 {
159 .val = 10483,
160 .val2 = 200000,
161 },
162 {
163 .val = 20966,
164 .val2 = 400000,
165 },
166 {
167 .val = 41932,
168 .val2 = 800000,
169 },
170 {
171 .val = 83865,
172 .val2 = 600000,
173 },
174 };
175
176 static const struct opt3001_scale opt3002_scales[] = {
177 {
178 .val = 4914,
179 .val2 = 0,
180 },
181 {
182 .val = 9828,
183 .val2 = 0,
184 },
185 {
186 .val = 19656,
187 .val2 = 0,
188 },
189 {
190 .val = 39312,
191 .val2 = 0,
192 },
193 {
194 .val = 78624,
195 .val2 = 0,
196 },
197 {
198 .val = 157248,
199 .val2 = 0,
200 },
201 {
202 .val = 314496,
203 .val2 = 0,
204 },
205 {
206 .val = 628992,
207 .val2 = 0,
208 },
209 {
210 .val = 1257984,
211 .val2 = 0,
212 },
213 {
214 .val = 2515968,
215 .val2 = 0,
216 },
217 {
218 .val = 5031936,
219 .val2 = 0,
220 },
221 {
222 .val = 10063872,
223 .val2 = 0,
224 },
225 };
226
opt3001_find_scale(const struct opt3001 * opt,int val,int val2,u8 * exponent)227 static int opt3001_find_scale(const struct opt3001 *opt, int val,
228 int val2, u8 *exponent)
229 {
230 int i;
231 for (i = 0; i < ARRAY_SIZE(*opt->chip_info->scales); i++) {
232 const struct opt3001_scale *scale = &(*opt->chip_info->scales)[i];
233 /*
234 * Compare the integer and micro parts to determine value scale.
235 */
236 if (val < scale->val ||
237 (val == scale->val && val2 <= scale->val2)) {
238 *exponent = i;
239 return 0;
240 }
241 }
242
243 return -EINVAL;
244 }
245
opt3001_to_iio_ret(struct opt3001 * opt,u8 exponent,u16 mantissa,int * val,int * val2)246 static void opt3001_to_iio_ret(struct opt3001 *opt, u8 exponent,
247 u16 mantissa, int *val, int *val2)
248 {
249 int ret;
250 int whole = opt->chip_info->factor_whole;
251 int integer = opt->chip_info->factor_integer;
252 int decimal = opt->chip_info->factor_decimal;
253
254 ret = whole * (mantissa << exponent);
255 *val = ret / integer;
256 *val2 = (ret - (*val * integer)) * decimal;
257 }
258
opt3001_set_mode(struct opt3001 * opt,u16 * reg,u16 mode)259 static void opt3001_set_mode(struct opt3001 *opt, u16 *reg, u16 mode)
260 {
261 *reg &= ~OPT3001_CONFIGURATION_M_MASK;
262 *reg |= mode;
263 opt->mode = mode;
264 }
265
266 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.8");
267
268 static struct attribute *opt3001_attributes[] = {
269 &iio_const_attr_integration_time_available.dev_attr.attr,
270 NULL
271 };
272
273 static const struct attribute_group opt3001_attribute_group = {
274 .attrs = opt3001_attributes,
275 };
276
277 static const struct iio_event_spec opt3001_event_spec[] = {
278 {
279 .type = IIO_EV_TYPE_THRESH,
280 .dir = IIO_EV_DIR_RISING,
281 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
282 BIT(IIO_EV_INFO_ENABLE),
283 },
284 {
285 .type = IIO_EV_TYPE_THRESH,
286 .dir = IIO_EV_DIR_FALLING,
287 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
288 BIT(IIO_EV_INFO_ENABLE),
289 },
290 };
291
292 static const struct iio_chan_spec opt3001_channels[] = {
293 {
294 .type = IIO_LIGHT,
295 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
296 BIT(IIO_CHAN_INFO_INT_TIME),
297 .event_spec = opt3001_event_spec,
298 .num_event_specs = ARRAY_SIZE(opt3001_event_spec),
299 },
300 IIO_CHAN_SOFT_TIMESTAMP(1),
301 };
302
303 static const struct iio_chan_spec opt3002_channels[] = {
304 {
305 .type = IIO_INTENSITY,
306 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
307 BIT(IIO_CHAN_INFO_INT_TIME),
308 .event_spec = opt3001_event_spec,
309 .num_event_specs = ARRAY_SIZE(opt3001_event_spec),
310 },
311 IIO_CHAN_SOFT_TIMESTAMP(1),
312 };
313
opt3001_get_processed(struct opt3001 * opt,int * val,int * val2)314 static int opt3001_get_processed(struct opt3001 *opt, int *val, int *val2)
315 {
316 int ret;
317 u16 mantissa;
318 u16 reg;
319 u8 exponent;
320 u16 value;
321 long timeout;
322
323 if (opt->use_irq) {
324 /*
325 * Enable the end-of-conversion interrupt mechanism. Note that
326 * doing so will overwrite the low-level limit value however we
327 * will restore this value later on.
328 */
329 ret = i2c_smbus_write_word_swapped(opt->client,
330 OPT3001_LOW_LIMIT,
331 OPT3001_LOW_LIMIT_EOC_ENABLE);
332 if (ret < 0) {
333 dev_err(opt->dev, "failed to write register %02x\n",
334 OPT3001_LOW_LIMIT);
335 return ret;
336 }
337
338 /* Allow IRQ to access the device despite lock being set */
339 opt->ok_to_ignore_lock = true;
340 }
341
342 /* Reset data-ready indicator flag */
343 opt->result_ready = false;
344
345 /* Configure for single-conversion mode and start a new conversion */
346 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
347 if (ret < 0) {
348 dev_err(opt->dev, "failed to read register %02x\n",
349 OPT3001_CONFIGURATION);
350 goto err;
351 }
352
353 reg = ret;
354 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SINGLE);
355
356 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION,
357 reg);
358 if (ret < 0) {
359 dev_err(opt->dev, "failed to write register %02x\n",
360 OPT3001_CONFIGURATION);
361 goto err;
362 }
363
364 if (opt->use_irq) {
365 /* Wait for the IRQ to indicate the conversion is complete */
366 ret = wait_event_timeout(opt->result_ready_queue,
367 opt->result_ready,
368 msecs_to_jiffies(OPT3001_RESULT_READY_LONG));
369 if (ret == 0)
370 return -ETIMEDOUT;
371 } else {
372 /* Sleep for result ready time */
373 timeout = (opt->int_time == OPT3001_INT_TIME_SHORT) ?
374 OPT3001_RESULT_READY_SHORT : OPT3001_RESULT_READY_LONG;
375 msleep(timeout);
376
377 /* Check result ready flag */
378 ret = i2c_smbus_read_word_swapped(opt->client,
379 OPT3001_CONFIGURATION);
380 if (ret < 0) {
381 dev_err(opt->dev, "failed to read register %02x\n",
382 OPT3001_CONFIGURATION);
383 goto err;
384 }
385
386 if (!(ret & OPT3001_CONFIGURATION_CRF)) {
387 ret = -ETIMEDOUT;
388 goto err;
389 }
390
391 /* Obtain value */
392 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_RESULT);
393 if (ret < 0) {
394 dev_err(opt->dev, "failed to read register %02x\n",
395 OPT3001_RESULT);
396 goto err;
397 }
398 opt->result = ret;
399 opt->result_ready = true;
400 }
401
402 err:
403 if (opt->use_irq)
404 /* Disallow IRQ to access the device while lock is active */
405 opt->ok_to_ignore_lock = false;
406
407 if (ret < 0)
408 return ret;
409
410 if (opt->use_irq) {
411 /*
412 * Disable the end-of-conversion interrupt mechanism by
413 * restoring the low-level limit value (clearing
414 * OPT3001_LOW_LIMIT_EOC_ENABLE). Note that selectively clearing
415 * those enable bits would affect the actual limit value due to
416 * bit-overlap and therefore can't be done.
417 */
418 value = (opt->low_thresh_exp << 12) | opt->low_thresh_mantissa;
419 ret = i2c_smbus_write_word_swapped(opt->client,
420 OPT3001_LOW_LIMIT,
421 value);
422 if (ret < 0) {
423 dev_err(opt->dev, "failed to write register %02x\n",
424 OPT3001_LOW_LIMIT);
425 return ret;
426 }
427 }
428
429 exponent = OPT3001_REG_EXPONENT(opt->result);
430 mantissa = OPT3001_REG_MANTISSA(opt->result);
431
432 opt3001_to_iio_ret(opt, exponent, mantissa, val, val2);
433
434 return IIO_VAL_INT_PLUS_MICRO;
435 }
436
opt3001_get_int_time(struct opt3001 * opt,int * val,int * val2)437 static int opt3001_get_int_time(struct opt3001 *opt, int *val, int *val2)
438 {
439 *val = 0;
440 *val2 = opt->int_time;
441
442 return IIO_VAL_INT_PLUS_MICRO;
443 }
444
opt3001_set_int_time(struct opt3001 * opt,int time)445 static int opt3001_set_int_time(struct opt3001 *opt, int time)
446 {
447 int ret;
448 u16 reg;
449
450 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
451 if (ret < 0) {
452 dev_err(opt->dev, "failed to read register %02x\n",
453 OPT3001_CONFIGURATION);
454 return ret;
455 }
456
457 reg = ret;
458
459 switch (time) {
460 case OPT3001_INT_TIME_SHORT:
461 reg &= ~OPT3001_CONFIGURATION_CT;
462 opt->int_time = OPT3001_INT_TIME_SHORT;
463 break;
464 case OPT3001_INT_TIME_LONG:
465 reg |= OPT3001_CONFIGURATION_CT;
466 opt->int_time = OPT3001_INT_TIME_LONG;
467 break;
468 default:
469 return -EINVAL;
470 }
471
472 return i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION,
473 reg);
474 }
475
opt3001_read_raw(struct iio_dev * iio,struct iio_chan_spec const * chan,int * val,int * val2,long mask)476 static int opt3001_read_raw(struct iio_dev *iio,
477 struct iio_chan_spec const *chan, int *val, int *val2,
478 long mask)
479 {
480 struct opt3001 *opt = iio_priv(iio);
481 int ret;
482
483 if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS)
484 return -EBUSY;
485
486 if (chan->type != opt->chip_info->chan_type)
487 return -EINVAL;
488
489 mutex_lock(&opt->lock);
490
491 switch (mask) {
492 case IIO_CHAN_INFO_RAW:
493 case IIO_CHAN_INFO_PROCESSED:
494 ret = opt3001_get_processed(opt, val, val2);
495 break;
496 case IIO_CHAN_INFO_INT_TIME:
497 ret = opt3001_get_int_time(opt, val, val2);
498 break;
499 default:
500 ret = -EINVAL;
501 }
502
503 mutex_unlock(&opt->lock);
504
505 return ret;
506 }
507
opt3001_write_raw(struct iio_dev * iio,struct iio_chan_spec const * chan,int val,int val2,long mask)508 static int opt3001_write_raw(struct iio_dev *iio,
509 struct iio_chan_spec const *chan, int val, int val2,
510 long mask)
511 {
512 struct opt3001 *opt = iio_priv(iio);
513 int ret;
514
515 if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS)
516 return -EBUSY;
517
518 if (chan->type != opt->chip_info->chan_type)
519 return -EINVAL;
520
521 if (mask != IIO_CHAN_INFO_INT_TIME)
522 return -EINVAL;
523
524 if (val != 0)
525 return -EINVAL;
526
527 mutex_lock(&opt->lock);
528 ret = opt3001_set_int_time(opt, val2);
529 mutex_unlock(&opt->lock);
530
531 return ret;
532 }
533
opt3001_read_event_value(struct iio_dev * iio,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)534 static int opt3001_read_event_value(struct iio_dev *iio,
535 const struct iio_chan_spec *chan, enum iio_event_type type,
536 enum iio_event_direction dir, enum iio_event_info info,
537 int *val, int *val2)
538 {
539 struct opt3001 *opt = iio_priv(iio);
540 int ret = IIO_VAL_INT_PLUS_MICRO;
541
542 mutex_lock(&opt->lock);
543
544 switch (dir) {
545 case IIO_EV_DIR_RISING:
546 opt3001_to_iio_ret(opt, opt->high_thresh_exp,
547 opt->high_thresh_mantissa, val, val2);
548 break;
549 case IIO_EV_DIR_FALLING:
550 opt3001_to_iio_ret(opt, opt->low_thresh_exp,
551 opt->low_thresh_mantissa, val, val2);
552 break;
553 default:
554 ret = -EINVAL;
555 }
556
557 mutex_unlock(&opt->lock);
558
559 return ret;
560 }
561
opt3001_write_event_value(struct iio_dev * iio,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)562 static int opt3001_write_event_value(struct iio_dev *iio,
563 const struct iio_chan_spec *chan, enum iio_event_type type,
564 enum iio_event_direction dir, enum iio_event_info info,
565 int val, int val2)
566 {
567 struct opt3001 *opt = iio_priv(iio);
568 int ret;
569 int whole;
570 int integer;
571 int decimal;
572
573 u16 mantissa;
574 u16 value;
575 u16 reg;
576
577 u8 exponent;
578
579 if (val < 0)
580 return -EINVAL;
581
582 mutex_lock(&opt->lock);
583
584 ret = opt3001_find_scale(opt, val, val2, &exponent);
585 if (ret < 0) {
586 dev_err(opt->dev, "can't find scale for %d.%06u\n", val, val2);
587 goto err;
588 }
589
590 whole = opt->chip_info->factor_whole;
591 integer = opt->chip_info->factor_integer;
592 decimal = opt->chip_info->factor_decimal;
593
594 mantissa = (((val * integer) + (val2 / decimal)) / whole) >> exponent;
595
596 value = (exponent << 12) | mantissa;
597
598 switch (dir) {
599 case IIO_EV_DIR_RISING:
600 reg = OPT3001_HIGH_LIMIT;
601 opt->high_thresh_mantissa = mantissa;
602 opt->high_thresh_exp = exponent;
603 break;
604 case IIO_EV_DIR_FALLING:
605 reg = OPT3001_LOW_LIMIT;
606 opt->low_thresh_mantissa = mantissa;
607 opt->low_thresh_exp = exponent;
608 break;
609 default:
610 ret = -EINVAL;
611 goto err;
612 }
613
614 ret = i2c_smbus_write_word_swapped(opt->client, reg, value);
615 if (ret < 0) {
616 dev_err(opt->dev, "failed to write register %02x\n", reg);
617 goto err;
618 }
619
620 err:
621 mutex_unlock(&opt->lock);
622
623 return ret;
624 }
625
opt3001_read_event_config(struct iio_dev * iio,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir)626 static int opt3001_read_event_config(struct iio_dev *iio,
627 const struct iio_chan_spec *chan, enum iio_event_type type,
628 enum iio_event_direction dir)
629 {
630 struct opt3001 *opt = iio_priv(iio);
631
632 return opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS;
633 }
634
opt3001_write_event_config(struct iio_dev * iio,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,bool state)635 static int opt3001_write_event_config(struct iio_dev *iio,
636 const struct iio_chan_spec *chan, enum iio_event_type type,
637 enum iio_event_direction dir, bool state)
638 {
639 struct opt3001 *opt = iio_priv(iio);
640 int ret;
641 u16 mode;
642 u16 reg;
643
644 if (state && opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS)
645 return 0;
646
647 if (!state && opt->mode == OPT3001_CONFIGURATION_M_SHUTDOWN)
648 return 0;
649
650 mutex_lock(&opt->lock);
651
652 mode = state ? OPT3001_CONFIGURATION_M_CONTINUOUS
653 : OPT3001_CONFIGURATION_M_SHUTDOWN;
654
655 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
656 if (ret < 0) {
657 dev_err(opt->dev, "failed to read register %02x\n",
658 OPT3001_CONFIGURATION);
659 goto err;
660 }
661
662 reg = ret;
663 opt3001_set_mode(opt, ®, mode);
664
665 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION,
666 reg);
667 if (ret < 0) {
668 dev_err(opt->dev, "failed to write register %02x\n",
669 OPT3001_CONFIGURATION);
670 goto err;
671 }
672
673 err:
674 mutex_unlock(&opt->lock);
675
676 return ret;
677 }
678
679 static const struct iio_info opt3001_info = {
680 .attrs = &opt3001_attribute_group,
681 .read_raw = opt3001_read_raw,
682 .write_raw = opt3001_write_raw,
683 .read_event_value = opt3001_read_event_value,
684 .write_event_value = opt3001_write_event_value,
685 .read_event_config = opt3001_read_event_config,
686 .write_event_config = opt3001_write_event_config,
687 };
688
opt3001_read_id(struct opt3001 * opt)689 static int opt3001_read_id(struct opt3001 *opt)
690 {
691 char manufacturer[2];
692 u16 device_id;
693 int ret;
694
695 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_MANUFACTURER_ID);
696 if (ret < 0) {
697 dev_err(opt->dev, "failed to read register %02x\n",
698 OPT3001_MANUFACTURER_ID);
699 return ret;
700 }
701
702 manufacturer[0] = ret >> 8;
703 manufacturer[1] = ret & 0xff;
704
705 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_DEVICE_ID);
706 if (ret < 0) {
707 dev_err(opt->dev, "failed to read register %02x\n",
708 OPT3001_DEVICE_ID);
709 return ret;
710 }
711
712 device_id = ret;
713
714 dev_info(opt->dev, "Found %c%c OPT%04x\n", manufacturer[0],
715 manufacturer[1], device_id);
716
717 return 0;
718 }
719
opt3001_configure(struct opt3001 * opt)720 static int opt3001_configure(struct opt3001 *opt)
721 {
722 int ret;
723 u16 reg;
724
725 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
726 if (ret < 0) {
727 dev_err(opt->dev, "failed to read register %02x\n",
728 OPT3001_CONFIGURATION);
729 return ret;
730 }
731
732 reg = ret;
733
734 /* Enable automatic full-scale setting mode */
735 reg &= ~OPT3001_CONFIGURATION_RN_MASK;
736 reg |= OPT3001_CONFIGURATION_RN_AUTO;
737
738 /* Reflect status of the device's integration time setting */
739 if (reg & OPT3001_CONFIGURATION_CT)
740 opt->int_time = OPT3001_INT_TIME_LONG;
741 else
742 opt->int_time = OPT3001_INT_TIME_SHORT;
743
744 /* Ensure device is in shutdown initially */
745 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SHUTDOWN);
746
747 /* Configure for latched window-style comparison operation */
748 reg |= OPT3001_CONFIGURATION_L;
749 reg &= ~OPT3001_CONFIGURATION_POL;
750 reg &= ~OPT3001_CONFIGURATION_ME;
751 reg &= ~OPT3001_CONFIGURATION_FC_MASK;
752
753 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION,
754 reg);
755 if (ret < 0) {
756 dev_err(opt->dev, "failed to write register %02x\n",
757 OPT3001_CONFIGURATION);
758 return ret;
759 }
760
761 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_LOW_LIMIT);
762 if (ret < 0) {
763 dev_err(opt->dev, "failed to read register %02x\n",
764 OPT3001_LOW_LIMIT);
765 return ret;
766 }
767
768 opt->low_thresh_mantissa = OPT3001_REG_MANTISSA(ret);
769 opt->low_thresh_exp = OPT3001_REG_EXPONENT(ret);
770
771 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_HIGH_LIMIT);
772 if (ret < 0) {
773 dev_err(opt->dev, "failed to read register %02x\n",
774 OPT3001_HIGH_LIMIT);
775 return ret;
776 }
777
778 opt->high_thresh_mantissa = OPT3001_REG_MANTISSA(ret);
779 opt->high_thresh_exp = OPT3001_REG_EXPONENT(ret);
780
781 return 0;
782 }
783
opt3001_irq(int irq,void * _iio)784 static irqreturn_t opt3001_irq(int irq, void *_iio)
785 {
786 struct iio_dev *iio = _iio;
787 struct opt3001 *opt = iio_priv(iio);
788 int ret;
789 bool wake_result_ready_queue = false;
790 enum iio_chan_type chan_type = opt->chip_info->chan_type;
791
792 if (!opt->ok_to_ignore_lock)
793 mutex_lock(&opt->lock);
794
795 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
796 if (ret < 0) {
797 dev_err(opt->dev, "failed to read register %02x\n",
798 OPT3001_CONFIGURATION);
799 goto out;
800 }
801
802 if ((ret & OPT3001_CONFIGURATION_M_MASK) ==
803 OPT3001_CONFIGURATION_M_CONTINUOUS) {
804 if (ret & OPT3001_CONFIGURATION_FH)
805 iio_push_event(iio,
806 IIO_UNMOD_EVENT_CODE(chan_type, 0,
807 IIO_EV_TYPE_THRESH,
808 IIO_EV_DIR_RISING),
809 iio_get_time_ns(iio));
810 if (ret & OPT3001_CONFIGURATION_FL)
811 iio_push_event(iio,
812 IIO_UNMOD_EVENT_CODE(chan_type, 0,
813 IIO_EV_TYPE_THRESH,
814 IIO_EV_DIR_FALLING),
815 iio_get_time_ns(iio));
816 } else if (ret & OPT3001_CONFIGURATION_CRF) {
817 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_RESULT);
818 if (ret < 0) {
819 dev_err(opt->dev, "failed to read register %02x\n",
820 OPT3001_RESULT);
821 goto out;
822 }
823 opt->result = ret;
824 opt->result_ready = true;
825 wake_result_ready_queue = true;
826 }
827
828 out:
829 if (!opt->ok_to_ignore_lock)
830 mutex_unlock(&opt->lock);
831
832 if (wake_result_ready_queue)
833 wake_up(&opt->result_ready_queue);
834
835 return IRQ_HANDLED;
836 }
837
opt3001_probe(struct i2c_client * client)838 static int opt3001_probe(struct i2c_client *client)
839 {
840 struct device *dev = &client->dev;
841
842 struct iio_dev *iio;
843 struct opt3001 *opt;
844 int irq = client->irq;
845 int ret;
846
847 iio = devm_iio_device_alloc(dev, sizeof(*opt));
848 if (!iio)
849 return -ENOMEM;
850
851 opt = iio_priv(iio);
852 opt->client = client;
853 opt->dev = dev;
854 opt->chip_info = i2c_get_match_data(client);
855
856 mutex_init(&opt->lock);
857 init_waitqueue_head(&opt->result_ready_queue);
858 i2c_set_clientdata(client, iio);
859
860 if (opt->chip_info->has_id) {
861 ret = opt3001_read_id(opt);
862 if (ret)
863 return ret;
864 }
865
866 ret = opt3001_configure(opt);
867 if (ret)
868 return ret;
869
870 iio->name = client->name;
871 iio->channels = *opt->chip_info->channels;
872 iio->num_channels = opt->chip_info->num_channels;
873 iio->modes = INDIO_DIRECT_MODE;
874 iio->info = &opt3001_info;
875
876 ret = devm_iio_device_register(dev, iio);
877 if (ret) {
878 dev_err(dev, "failed to register IIO device\n");
879 return ret;
880 }
881
882 /* Make use of INT pin only if valid IRQ no. is given */
883 if (irq > 0) {
884 ret = request_threaded_irq(irq, NULL, opt3001_irq,
885 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
886 "opt3001", iio);
887 if (ret) {
888 dev_err(dev, "failed to request IRQ #%d\n", irq);
889 return ret;
890 }
891 opt->use_irq = true;
892 } else {
893 dev_dbg(opt->dev, "enabling interrupt-less operation\n");
894 }
895
896 return 0;
897 }
898
opt3001_remove(struct i2c_client * client)899 static void opt3001_remove(struct i2c_client *client)
900 {
901 struct iio_dev *iio = i2c_get_clientdata(client);
902 struct opt3001 *opt = iio_priv(iio);
903 int ret;
904 u16 reg;
905
906 if (opt->use_irq)
907 free_irq(client->irq, iio);
908
909 ret = i2c_smbus_read_word_swapped(opt->client, OPT3001_CONFIGURATION);
910 if (ret < 0) {
911 dev_err(opt->dev, "failed to read register %02x\n",
912 OPT3001_CONFIGURATION);
913 return;
914 }
915
916 reg = ret;
917 opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SHUTDOWN);
918
919 ret = i2c_smbus_write_word_swapped(opt->client, OPT3001_CONFIGURATION,
920 reg);
921 if (ret < 0) {
922 dev_err(opt->dev, "failed to write register %02x\n",
923 OPT3001_CONFIGURATION);
924 }
925 }
926
927 static const struct opt3001_chip_info opt3001_chip_information = {
928 .channels = &opt3001_channels,
929 .chan_type = IIO_LIGHT,
930 .num_channels = ARRAY_SIZE(opt3001_channels),
931 .scales = &opt3001_scales,
932 .factor_whole = 10,
933 .factor_integer = 1000,
934 .factor_decimal = 1000,
935 .has_id = true,
936 };
937
938 static const struct opt3001_chip_info opt3002_chip_information = {
939 .channels = &opt3002_channels,
940 .chan_type = IIO_INTENSITY,
941 .num_channels = ARRAY_SIZE(opt3002_channels),
942 .scales = &opt3002_scales,
943 .factor_whole = 12,
944 .factor_integer = 10,
945 .factor_decimal = 100000,
946 .has_id = false,
947 };
948
949 static const struct i2c_device_id opt3001_id[] = {
950 { "opt3001", (kernel_ulong_t)&opt3001_chip_information },
951 { "opt3002", (kernel_ulong_t)&opt3002_chip_information },
952 { } /* Terminating Entry */
953 };
954 MODULE_DEVICE_TABLE(i2c, opt3001_id);
955
956 static const struct of_device_id opt3001_of_match[] = {
957 { .compatible = "ti,opt3001", .data = &opt3001_chip_information },
958 { .compatible = "ti,opt3002", .data = &opt3002_chip_information },
959 { }
960 };
961 MODULE_DEVICE_TABLE(of, opt3001_of_match);
962
963 static struct i2c_driver opt3001_driver = {
964 .probe = opt3001_probe,
965 .remove = opt3001_remove,
966 .id_table = opt3001_id,
967
968 .driver = {
969 .name = "opt3001",
970 .of_match_table = opt3001_of_match,
971 },
972 };
973
974 module_i2c_driver(opt3001_driver);
975
976 MODULE_LICENSE("GPL v2");
977 MODULE_AUTHOR("Andreas Dannenberg <dannenberg@ti.com>");
978 MODULE_DESCRIPTION("Texas Instruments OPT3001 Light Sensor Driver");
979