xref: /linux/drivers/iio/light/ltr501.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ltr501.c - Support for Lite-On LTR501 ambient light and proximity sensor
4  *
5  * Copyright 2014 Peter Meerwald <pmeerw@pmeerw.net>
6  *
7  * 7-bit I2C slave address 0x23
8  *
9  * TODO: IR LED characteristics
10  */
11 
12 #include <linux/module.h>
13 #include <linux/i2c.h>
14 #include <linux/err.h>
15 #include <linux/delay.h>
16 #include <linux/regmap.h>
17 #include <linux/acpi.h>
18 
19 #include <linux/iio/iio.h>
20 #include <linux/iio/events.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/trigger_consumer.h>
23 #include <linux/iio/buffer.h>
24 #include <linux/iio/triggered_buffer.h>
25 
26 #define LTR501_DRV_NAME "ltr501"
27 
28 #define LTR501_ALS_CONTR 0x80 /* ALS operation mode, SW reset */
29 #define LTR501_PS_CONTR 0x81 /* PS operation mode */
30 #define LTR501_PS_MEAS_RATE 0x84 /* measurement rate*/
31 #define LTR501_ALS_MEAS_RATE 0x85 /* ALS integ time, measurement rate*/
32 #define LTR501_PART_ID 0x86
33 #define LTR501_MANUFAC_ID 0x87
34 #define LTR501_ALS_DATA1 0x88 /* 16-bit, little endian */
35 #define LTR501_ALS_DATA0 0x8a /* 16-bit, little endian */
36 #define LTR501_ALS_PS_STATUS 0x8c
37 #define LTR501_PS_DATA 0x8d /* 16-bit, little endian */
38 #define LTR501_INTR 0x8f /* output mode, polarity, mode */
39 #define LTR501_PS_THRESH_UP 0x90 /* 11 bit, ps upper threshold */
40 #define LTR501_PS_THRESH_LOW 0x92 /* 11 bit, ps lower threshold */
41 #define LTR501_ALS_THRESH_UP 0x97 /* 16 bit, ALS upper threshold */
42 #define LTR501_ALS_THRESH_LOW 0x99 /* 16 bit, ALS lower threshold */
43 #define LTR501_INTR_PRST 0x9e /* ps thresh, als thresh */
44 #define LTR501_MAX_REG 0x9f
45 
46 #define LTR501_ALS_CONTR_SW_RESET BIT(2)
47 #define LTR501_CONTR_PS_GAIN_MASK (BIT(3) | BIT(2))
48 #define LTR501_CONTR_PS_GAIN_SHIFT 2
49 #define LTR501_CONTR_ALS_GAIN_MASK BIT(3)
50 #define LTR501_CONTR_ACTIVE BIT(1)
51 
52 #define LTR501_STATUS_ALS_INTR BIT(3)
53 #define LTR501_STATUS_ALS_RDY BIT(2)
54 #define LTR501_STATUS_PS_INTR BIT(1)
55 #define LTR501_STATUS_PS_RDY BIT(0)
56 
57 #define LTR501_PS_DATA_MASK 0x7ff
58 #define LTR501_PS_THRESH_MASK 0x7ff
59 #define LTR501_ALS_THRESH_MASK 0xffff
60 
61 #define LTR501_ALS_DEF_PERIOD 500000
62 #define LTR501_PS_DEF_PERIOD 100000
63 
64 #define LTR501_REGMAP_NAME "ltr501_regmap"
65 
66 #define LTR501_LUX_CONV(vis_coeff, vis_data, ir_coeff, ir_data) \
67 			((vis_coeff * vis_data) - (ir_coeff * ir_data))
68 
69 static const int int_time_mapping[] = {100000, 50000, 200000, 400000};
70 
71 static const struct reg_field reg_field_it =
72 				REG_FIELD(LTR501_ALS_MEAS_RATE, 3, 4);
73 static const struct reg_field reg_field_als_intr =
74 				REG_FIELD(LTR501_INTR, 1, 1);
75 static const struct reg_field reg_field_ps_intr =
76 				REG_FIELD(LTR501_INTR, 0, 0);
77 static const struct reg_field reg_field_als_rate =
78 				REG_FIELD(LTR501_ALS_MEAS_RATE, 0, 2);
79 static const struct reg_field reg_field_ps_rate =
80 				REG_FIELD(LTR501_PS_MEAS_RATE, 0, 3);
81 static const struct reg_field reg_field_als_prst =
82 				REG_FIELD(LTR501_INTR_PRST, 0, 3);
83 static const struct reg_field reg_field_ps_prst =
84 				REG_FIELD(LTR501_INTR_PRST, 4, 7);
85 
86 struct ltr501_samp_table {
87 	int freq_val;  /* repetition frequency in micro HZ*/
88 	int time_val; /* repetition rate in micro seconds */
89 };
90 
91 #define LTR501_RESERVED_GAIN -1
92 
93 enum {
94 	ltr501 = 0,
95 	ltr559,
96 	ltr301,
97 };
98 
99 struct ltr501_gain {
100 	int scale;
101 	int uscale;
102 };
103 
104 static const struct ltr501_gain ltr501_als_gain_tbl[] = {
105 	{1, 0},
106 	{0, 5000},
107 };
108 
109 static const struct ltr501_gain ltr559_als_gain_tbl[] = {
110 	{1, 0},
111 	{0, 500000},
112 	{0, 250000},
113 	{0, 125000},
114 	{LTR501_RESERVED_GAIN, LTR501_RESERVED_GAIN},
115 	{LTR501_RESERVED_GAIN, LTR501_RESERVED_GAIN},
116 	{0, 20000},
117 	{0, 10000},
118 };
119 
120 static const struct ltr501_gain ltr501_ps_gain_tbl[] = {
121 	{1, 0},
122 	{0, 250000},
123 	{0, 125000},
124 	{0, 62500},
125 };
126 
127 static const struct ltr501_gain ltr559_ps_gain_tbl[] = {
128 	{0, 62500}, /* x16 gain */
129 	{0, 31250}, /* x32 gain */
130 	{0, 15625}, /* bits X1 are for x64 gain */
131 	{0, 15624},
132 };
133 
134 struct ltr501_chip_info {
135 	u8 partid;
136 	const struct ltr501_gain *als_gain;
137 	int als_gain_tbl_size;
138 	const struct ltr501_gain *ps_gain;
139 	int ps_gain_tbl_size;
140 	u8 als_mode_active;
141 	u8 als_gain_mask;
142 	u8 als_gain_shift;
143 	struct iio_chan_spec const *channels;
144 	const int no_channels;
145 	const struct iio_info *info;
146 	const struct iio_info *info_no_irq;
147 };
148 
149 struct ltr501_data {
150 	struct i2c_client *client;
151 	struct mutex lock_als, lock_ps;
152 	struct ltr501_chip_info *chip_info;
153 	u8 als_contr, ps_contr;
154 	int als_period, ps_period; /* period in micro seconds */
155 	struct regmap *regmap;
156 	struct regmap_field *reg_it;
157 	struct regmap_field *reg_als_intr;
158 	struct regmap_field *reg_ps_intr;
159 	struct regmap_field *reg_als_rate;
160 	struct regmap_field *reg_ps_rate;
161 	struct regmap_field *reg_als_prst;
162 	struct regmap_field *reg_ps_prst;
163 };
164 
165 static const struct ltr501_samp_table ltr501_als_samp_table[] = {
166 			{20000000, 50000}, {10000000, 100000},
167 			{5000000, 200000}, {2000000, 500000},
168 			{1000000, 1000000}, {500000, 2000000},
169 			{500000, 2000000}, {500000, 2000000}
170 };
171 
172 static const struct ltr501_samp_table ltr501_ps_samp_table[] = {
173 			{20000000, 50000}, {14285714, 70000},
174 			{10000000, 100000}, {5000000, 200000},
175 			{2000000, 500000}, {1000000, 1000000},
176 			{500000, 2000000}, {500000, 2000000},
177 			{500000, 2000000}
178 };
179 
180 static int ltr501_match_samp_freq(const struct ltr501_samp_table *tab,
181 					   int len, int val, int val2)
182 {
183 	int i, freq;
184 
185 	freq = val * 1000000 + val2;
186 
187 	for (i = 0; i < len; i++) {
188 		if (tab[i].freq_val == freq)
189 			return i;
190 	}
191 
192 	return -EINVAL;
193 }
194 
195 static int ltr501_als_read_samp_freq(const struct ltr501_data *data,
196 				     int *val, int *val2)
197 {
198 	int ret, i;
199 
200 	ret = regmap_field_read(data->reg_als_rate, &i);
201 	if (ret < 0)
202 		return ret;
203 
204 	if (i < 0 || i >= ARRAY_SIZE(ltr501_als_samp_table))
205 		return -EINVAL;
206 
207 	*val = ltr501_als_samp_table[i].freq_val / 1000000;
208 	*val2 = ltr501_als_samp_table[i].freq_val % 1000000;
209 
210 	return IIO_VAL_INT_PLUS_MICRO;
211 }
212 
213 static int ltr501_ps_read_samp_freq(const struct ltr501_data *data,
214 				    int *val, int *val2)
215 {
216 	int ret, i;
217 
218 	ret = regmap_field_read(data->reg_ps_rate, &i);
219 	if (ret < 0)
220 		return ret;
221 
222 	if (i < 0 || i >= ARRAY_SIZE(ltr501_ps_samp_table))
223 		return -EINVAL;
224 
225 	*val = ltr501_ps_samp_table[i].freq_val / 1000000;
226 	*val2 = ltr501_ps_samp_table[i].freq_val % 1000000;
227 
228 	return IIO_VAL_INT_PLUS_MICRO;
229 }
230 
231 static int ltr501_als_write_samp_freq(struct ltr501_data *data,
232 				      int val, int val2)
233 {
234 	int i, ret;
235 
236 	i = ltr501_match_samp_freq(ltr501_als_samp_table,
237 				   ARRAY_SIZE(ltr501_als_samp_table),
238 				   val, val2);
239 
240 	if (i < 0)
241 		return i;
242 
243 	mutex_lock(&data->lock_als);
244 	ret = regmap_field_write(data->reg_als_rate, i);
245 	mutex_unlock(&data->lock_als);
246 
247 	return ret;
248 }
249 
250 static int ltr501_ps_write_samp_freq(struct ltr501_data *data,
251 				     int val, int val2)
252 {
253 	int i, ret;
254 
255 	i = ltr501_match_samp_freq(ltr501_ps_samp_table,
256 				   ARRAY_SIZE(ltr501_ps_samp_table),
257 				   val, val2);
258 
259 	if (i < 0)
260 		return i;
261 
262 	mutex_lock(&data->lock_ps);
263 	ret = regmap_field_write(data->reg_ps_rate, i);
264 	mutex_unlock(&data->lock_ps);
265 
266 	return ret;
267 }
268 
269 static int ltr501_als_read_samp_period(const struct ltr501_data *data, int *val)
270 {
271 	int ret, i;
272 
273 	ret = regmap_field_read(data->reg_als_rate, &i);
274 	if (ret < 0)
275 		return ret;
276 
277 	if (i < 0 || i >= ARRAY_SIZE(ltr501_als_samp_table))
278 		return -EINVAL;
279 
280 	*val = ltr501_als_samp_table[i].time_val;
281 
282 	return IIO_VAL_INT;
283 }
284 
285 static int ltr501_ps_read_samp_period(const struct ltr501_data *data, int *val)
286 {
287 	int ret, i;
288 
289 	ret = regmap_field_read(data->reg_ps_rate, &i);
290 	if (ret < 0)
291 		return ret;
292 
293 	if (i < 0 || i >= ARRAY_SIZE(ltr501_ps_samp_table))
294 		return -EINVAL;
295 
296 	*val = ltr501_ps_samp_table[i].time_val;
297 
298 	return IIO_VAL_INT;
299 }
300 
301 /* IR and visible spectrum coeff's are given in data sheet */
302 static unsigned long ltr501_calculate_lux(u16 vis_data, u16 ir_data)
303 {
304 	unsigned long ratio, lux;
305 
306 	if (vis_data == 0)
307 		return 0;
308 
309 	/* multiply numerator by 100 to avoid handling ratio < 1 */
310 	ratio = DIV_ROUND_UP(ir_data * 100, ir_data + vis_data);
311 
312 	if (ratio < 45)
313 		lux = LTR501_LUX_CONV(1774, vis_data, -1105, ir_data);
314 	else if (ratio >= 45 && ratio < 64)
315 		lux = LTR501_LUX_CONV(3772, vis_data, 1336, ir_data);
316 	else if (ratio >= 64 && ratio < 85)
317 		lux = LTR501_LUX_CONV(1690, vis_data, 169, ir_data);
318 	else
319 		lux = 0;
320 
321 	return lux / 1000;
322 }
323 
324 static int ltr501_drdy(const struct ltr501_data *data, u8 drdy_mask)
325 {
326 	int tries = 100;
327 	int ret, status;
328 
329 	while (tries--) {
330 		ret = regmap_read(data->regmap, LTR501_ALS_PS_STATUS, &status);
331 		if (ret < 0)
332 			return ret;
333 		if ((status & drdy_mask) == drdy_mask)
334 			return 0;
335 		msleep(25);
336 	}
337 
338 	dev_err(&data->client->dev, "ltr501_drdy() failed, data not ready\n");
339 	return -EIO;
340 }
341 
342 static int ltr501_set_it_time(struct ltr501_data *data, int it)
343 {
344 	int ret, i, index = -1, status;
345 
346 	for (i = 0; i < ARRAY_SIZE(int_time_mapping); i++) {
347 		if (int_time_mapping[i] == it) {
348 			index = i;
349 			break;
350 		}
351 	}
352 	/* Make sure integ time index is valid */
353 	if (index < 0)
354 		return -EINVAL;
355 
356 	ret = regmap_read(data->regmap, LTR501_ALS_CONTR, &status);
357 	if (ret < 0)
358 		return ret;
359 
360 	if (status & LTR501_CONTR_ALS_GAIN_MASK) {
361 		/*
362 		 * 200 ms and 400 ms integ time can only be
363 		 * used in dynamic range 1
364 		 */
365 		if (index > 1)
366 			return -EINVAL;
367 	} else
368 		/* 50 ms integ time can only be used in dynamic range 2 */
369 		if (index == 1)
370 			return -EINVAL;
371 
372 	return regmap_field_write(data->reg_it, index);
373 }
374 
375 /* read int time in micro seconds */
376 static int ltr501_read_it_time(const struct ltr501_data *data,
377 			       int *val, int *val2)
378 {
379 	int ret, index;
380 
381 	ret = regmap_field_read(data->reg_it, &index);
382 	if (ret < 0)
383 		return ret;
384 
385 	/* Make sure integ time index is valid */
386 	if (index < 0 || index >= ARRAY_SIZE(int_time_mapping))
387 		return -EINVAL;
388 
389 	*val2 = int_time_mapping[index];
390 	*val = 0;
391 
392 	return IIO_VAL_INT_PLUS_MICRO;
393 }
394 
395 static int ltr501_read_als(const struct ltr501_data *data, __le16 buf[2])
396 {
397 	int ret;
398 
399 	ret = ltr501_drdy(data, LTR501_STATUS_ALS_RDY);
400 	if (ret < 0)
401 		return ret;
402 	/* always read both ALS channels in given order */
403 	return regmap_bulk_read(data->regmap, LTR501_ALS_DATA1,
404 				buf, 2 * sizeof(__le16));
405 }
406 
407 static int ltr501_read_ps(const struct ltr501_data *data)
408 {
409 	int ret, status;
410 
411 	ret = ltr501_drdy(data, LTR501_STATUS_PS_RDY);
412 	if (ret < 0)
413 		return ret;
414 
415 	ret = regmap_bulk_read(data->regmap, LTR501_PS_DATA,
416 			       &status, 2);
417 	if (ret < 0)
418 		return ret;
419 
420 	return status;
421 }
422 
423 static int ltr501_read_intr_prst(const struct ltr501_data *data,
424 				 enum iio_chan_type type,
425 				 int *val2)
426 {
427 	int ret, samp_period, prst;
428 
429 	switch (type) {
430 	case IIO_INTENSITY:
431 		ret = regmap_field_read(data->reg_als_prst, &prst);
432 		if (ret < 0)
433 			return ret;
434 
435 		ret = ltr501_als_read_samp_period(data, &samp_period);
436 
437 		if (ret < 0)
438 			return ret;
439 		*val2 = samp_period * prst;
440 		return IIO_VAL_INT_PLUS_MICRO;
441 	case IIO_PROXIMITY:
442 		ret = regmap_field_read(data->reg_ps_prst, &prst);
443 		if (ret < 0)
444 			return ret;
445 
446 		ret = ltr501_ps_read_samp_period(data, &samp_period);
447 
448 		if (ret < 0)
449 			return ret;
450 
451 		*val2 = samp_period * prst;
452 		return IIO_VAL_INT_PLUS_MICRO;
453 	default:
454 		return -EINVAL;
455 	}
456 
457 	return -EINVAL;
458 }
459 
460 static int ltr501_write_intr_prst(struct ltr501_data *data,
461 				  enum iio_chan_type type,
462 				  int val, int val2)
463 {
464 	int ret, samp_period, new_val;
465 	unsigned long period;
466 
467 	if (val < 0 || val2 < 0)
468 		return -EINVAL;
469 
470 	/* period in microseconds */
471 	period = ((val * 1000000) + val2);
472 
473 	switch (type) {
474 	case IIO_INTENSITY:
475 		ret = ltr501_als_read_samp_period(data, &samp_period);
476 		if (ret < 0)
477 			return ret;
478 
479 		/* period should be atleast equal to sampling period */
480 		if (period < samp_period)
481 			return -EINVAL;
482 
483 		new_val = DIV_ROUND_UP(period, samp_period);
484 		if (new_val < 0 || new_val > 0x0f)
485 			return -EINVAL;
486 
487 		mutex_lock(&data->lock_als);
488 		ret = regmap_field_write(data->reg_als_prst, new_val);
489 		mutex_unlock(&data->lock_als);
490 		if (ret >= 0)
491 			data->als_period = period;
492 
493 		return ret;
494 	case IIO_PROXIMITY:
495 		ret = ltr501_ps_read_samp_period(data, &samp_period);
496 		if (ret < 0)
497 			return ret;
498 
499 		/* period should be atleast equal to rate */
500 		if (period < samp_period)
501 			return -EINVAL;
502 
503 		new_val = DIV_ROUND_UP(period, samp_period);
504 		if (new_val < 0 || new_val > 0x0f)
505 			return -EINVAL;
506 
507 		mutex_lock(&data->lock_ps);
508 		ret = regmap_field_write(data->reg_ps_prst, new_val);
509 		mutex_unlock(&data->lock_ps);
510 		if (ret >= 0)
511 			data->ps_period = period;
512 
513 		return ret;
514 	default:
515 		return -EINVAL;
516 	}
517 
518 	return -EINVAL;
519 }
520 
521 static const struct iio_event_spec ltr501_als_event_spec[] = {
522 	{
523 		.type = IIO_EV_TYPE_THRESH,
524 		.dir = IIO_EV_DIR_RISING,
525 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
526 	}, {
527 		.type = IIO_EV_TYPE_THRESH,
528 		.dir = IIO_EV_DIR_FALLING,
529 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
530 	}, {
531 		.type = IIO_EV_TYPE_THRESH,
532 		.dir = IIO_EV_DIR_EITHER,
533 		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
534 				 BIT(IIO_EV_INFO_PERIOD),
535 	},
536 
537 };
538 
539 static const struct iio_event_spec ltr501_pxs_event_spec[] = {
540 	{
541 		.type = IIO_EV_TYPE_THRESH,
542 		.dir = IIO_EV_DIR_RISING,
543 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
544 	}, {
545 		.type = IIO_EV_TYPE_THRESH,
546 		.dir = IIO_EV_DIR_FALLING,
547 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
548 	}, {
549 		.type = IIO_EV_TYPE_THRESH,
550 		.dir = IIO_EV_DIR_EITHER,
551 		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
552 				 BIT(IIO_EV_INFO_PERIOD),
553 	},
554 };
555 
556 #define LTR501_INTENSITY_CHANNEL(_idx, _addr, _mod, _shared, \
557 				 _evspec, _evsize) { \
558 	.type = IIO_INTENSITY, \
559 	.modified = 1, \
560 	.address = (_addr), \
561 	.channel2 = (_mod), \
562 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
563 	.info_mask_shared_by_type = (_shared), \
564 	.scan_index = (_idx), \
565 	.scan_type = { \
566 		.sign = 'u', \
567 		.realbits = 16, \
568 		.storagebits = 16, \
569 		.endianness = IIO_CPU, \
570 	}, \
571 	.event_spec = _evspec,\
572 	.num_event_specs = _evsize,\
573 }
574 
575 #define LTR501_LIGHT_CHANNEL() { \
576 	.type = IIO_LIGHT, \
577 	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
578 	.scan_index = -1, \
579 }
580 
581 static const struct iio_chan_spec ltr501_channels[] = {
582 	LTR501_LIGHT_CHANNEL(),
583 	LTR501_INTENSITY_CHANNEL(0, LTR501_ALS_DATA0, IIO_MOD_LIGHT_BOTH, 0,
584 				 ltr501_als_event_spec,
585 				 ARRAY_SIZE(ltr501_als_event_spec)),
586 	LTR501_INTENSITY_CHANNEL(1, LTR501_ALS_DATA1, IIO_MOD_LIGHT_IR,
587 				 BIT(IIO_CHAN_INFO_SCALE) |
588 				 BIT(IIO_CHAN_INFO_INT_TIME) |
589 				 BIT(IIO_CHAN_INFO_SAMP_FREQ),
590 				 NULL, 0),
591 	{
592 		.type = IIO_PROXIMITY,
593 		.address = LTR501_PS_DATA,
594 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
595 			BIT(IIO_CHAN_INFO_SCALE),
596 		.scan_index = 2,
597 		.scan_type = {
598 			.sign = 'u',
599 			.realbits = 11,
600 			.storagebits = 16,
601 			.endianness = IIO_CPU,
602 		},
603 		.event_spec = ltr501_pxs_event_spec,
604 		.num_event_specs = ARRAY_SIZE(ltr501_pxs_event_spec),
605 	},
606 	IIO_CHAN_SOFT_TIMESTAMP(3),
607 };
608 
609 static const struct iio_chan_spec ltr301_channels[] = {
610 	LTR501_LIGHT_CHANNEL(),
611 	LTR501_INTENSITY_CHANNEL(0, LTR501_ALS_DATA0, IIO_MOD_LIGHT_BOTH, 0,
612 				 ltr501_als_event_spec,
613 				 ARRAY_SIZE(ltr501_als_event_spec)),
614 	LTR501_INTENSITY_CHANNEL(1, LTR501_ALS_DATA1, IIO_MOD_LIGHT_IR,
615 				 BIT(IIO_CHAN_INFO_SCALE) |
616 				 BIT(IIO_CHAN_INFO_INT_TIME) |
617 				 BIT(IIO_CHAN_INFO_SAMP_FREQ),
618 				 NULL, 0),
619 	IIO_CHAN_SOFT_TIMESTAMP(2),
620 };
621 
622 static int ltr501_read_raw(struct iio_dev *indio_dev,
623 			   struct iio_chan_spec const *chan,
624 			   int *val, int *val2, long mask)
625 {
626 	struct ltr501_data *data = iio_priv(indio_dev);
627 	__le16 buf[2];
628 	int ret, i;
629 
630 	switch (mask) {
631 	case IIO_CHAN_INFO_PROCESSED:
632 		switch (chan->type) {
633 		case IIO_LIGHT:
634 			ret = iio_device_claim_direct_mode(indio_dev);
635 			if (ret)
636 				return ret;
637 
638 			mutex_lock(&data->lock_als);
639 			ret = ltr501_read_als(data, buf);
640 			mutex_unlock(&data->lock_als);
641 			iio_device_release_direct_mode(indio_dev);
642 			if (ret < 0)
643 				return ret;
644 			*val = ltr501_calculate_lux(le16_to_cpu(buf[1]),
645 						    le16_to_cpu(buf[0]));
646 			return IIO_VAL_INT;
647 		default:
648 			return -EINVAL;
649 		}
650 	case IIO_CHAN_INFO_RAW:
651 		ret = iio_device_claim_direct_mode(indio_dev);
652 		if (ret)
653 			return ret;
654 
655 		switch (chan->type) {
656 		case IIO_INTENSITY:
657 			mutex_lock(&data->lock_als);
658 			ret = ltr501_read_als(data, buf);
659 			mutex_unlock(&data->lock_als);
660 			if (ret < 0)
661 				break;
662 			*val = le16_to_cpu(chan->address == LTR501_ALS_DATA1 ?
663 					   buf[0] : buf[1]);
664 			ret = IIO_VAL_INT;
665 			break;
666 		case IIO_PROXIMITY:
667 			mutex_lock(&data->lock_ps);
668 			ret = ltr501_read_ps(data);
669 			mutex_unlock(&data->lock_ps);
670 			if (ret < 0)
671 				break;
672 			*val = ret & LTR501_PS_DATA_MASK;
673 			ret = IIO_VAL_INT;
674 			break;
675 		default:
676 			ret = -EINVAL;
677 			break;
678 		}
679 
680 		iio_device_release_direct_mode(indio_dev);
681 		return ret;
682 
683 	case IIO_CHAN_INFO_SCALE:
684 		switch (chan->type) {
685 		case IIO_INTENSITY:
686 			i = (data->als_contr & data->chip_info->als_gain_mask)
687 			     >> data->chip_info->als_gain_shift;
688 			*val = data->chip_info->als_gain[i].scale;
689 			*val2 = data->chip_info->als_gain[i].uscale;
690 			return IIO_VAL_INT_PLUS_MICRO;
691 		case IIO_PROXIMITY:
692 			i = (data->ps_contr & LTR501_CONTR_PS_GAIN_MASK) >>
693 				LTR501_CONTR_PS_GAIN_SHIFT;
694 			*val = data->chip_info->ps_gain[i].scale;
695 			*val2 = data->chip_info->ps_gain[i].uscale;
696 			return IIO_VAL_INT_PLUS_MICRO;
697 		default:
698 			return -EINVAL;
699 		}
700 	case IIO_CHAN_INFO_INT_TIME:
701 		switch (chan->type) {
702 		case IIO_INTENSITY:
703 			return ltr501_read_it_time(data, val, val2);
704 		default:
705 			return -EINVAL;
706 		}
707 	case IIO_CHAN_INFO_SAMP_FREQ:
708 		switch (chan->type) {
709 		case IIO_INTENSITY:
710 			return ltr501_als_read_samp_freq(data, val, val2);
711 		case IIO_PROXIMITY:
712 			return ltr501_ps_read_samp_freq(data, val, val2);
713 		default:
714 			return -EINVAL;
715 		}
716 	}
717 	return -EINVAL;
718 }
719 
720 static int ltr501_get_gain_index(const struct ltr501_gain *gain, int size,
721 				 int val, int val2)
722 {
723 	int i;
724 
725 	for (i = 0; i < size; i++)
726 		if (val == gain[i].scale && val2 == gain[i].uscale)
727 			return i;
728 
729 	return -1;
730 }
731 
732 static int ltr501_write_raw(struct iio_dev *indio_dev,
733 			    struct iio_chan_spec const *chan,
734 			    int val, int val2, long mask)
735 {
736 	struct ltr501_data *data = iio_priv(indio_dev);
737 	int i, ret, freq_val, freq_val2;
738 	struct ltr501_chip_info *info = data->chip_info;
739 
740 	ret = iio_device_claim_direct_mode(indio_dev);
741 	if (ret)
742 		return ret;
743 
744 	switch (mask) {
745 	case IIO_CHAN_INFO_SCALE:
746 		switch (chan->type) {
747 		case IIO_INTENSITY:
748 			i = ltr501_get_gain_index(info->als_gain,
749 						  info->als_gain_tbl_size,
750 						  val, val2);
751 			if (i < 0) {
752 				ret = -EINVAL;
753 				break;
754 			}
755 
756 			data->als_contr &= ~info->als_gain_mask;
757 			data->als_contr |= i << info->als_gain_shift;
758 
759 			ret = regmap_write(data->regmap, LTR501_ALS_CONTR,
760 					   data->als_contr);
761 			break;
762 		case IIO_PROXIMITY:
763 			i = ltr501_get_gain_index(info->ps_gain,
764 						  info->ps_gain_tbl_size,
765 						  val, val2);
766 			if (i < 0) {
767 				ret = -EINVAL;
768 				break;
769 			}
770 			data->ps_contr &= ~LTR501_CONTR_PS_GAIN_MASK;
771 			data->ps_contr |= i << LTR501_CONTR_PS_GAIN_SHIFT;
772 
773 			ret = regmap_write(data->regmap, LTR501_PS_CONTR,
774 					   data->ps_contr);
775 			break;
776 		default:
777 			ret = -EINVAL;
778 			break;
779 		}
780 		break;
781 
782 	case IIO_CHAN_INFO_INT_TIME:
783 		switch (chan->type) {
784 		case IIO_INTENSITY:
785 			if (val != 0) {
786 				ret = -EINVAL;
787 				break;
788 			}
789 			mutex_lock(&data->lock_als);
790 			ret = ltr501_set_it_time(data, val2);
791 			mutex_unlock(&data->lock_als);
792 			break;
793 		default:
794 			ret = -EINVAL;
795 			break;
796 		}
797 		break;
798 
799 	case IIO_CHAN_INFO_SAMP_FREQ:
800 		switch (chan->type) {
801 		case IIO_INTENSITY:
802 			ret = ltr501_als_read_samp_freq(data, &freq_val,
803 							&freq_val2);
804 			if (ret < 0)
805 				break;
806 
807 			ret = ltr501_als_write_samp_freq(data, val, val2);
808 			if (ret < 0)
809 				break;
810 
811 			/* update persistence count when changing frequency */
812 			ret = ltr501_write_intr_prst(data, chan->type,
813 						     0, data->als_period);
814 
815 			if (ret < 0)
816 				ret = ltr501_als_write_samp_freq(data, freq_val,
817 								 freq_val2);
818 			break;
819 		case IIO_PROXIMITY:
820 			ret = ltr501_ps_read_samp_freq(data, &freq_val,
821 						       &freq_val2);
822 			if (ret < 0)
823 				break;
824 
825 			ret = ltr501_ps_write_samp_freq(data, val, val2);
826 			if (ret < 0)
827 				break;
828 
829 			/* update persistence count when changing frequency */
830 			ret = ltr501_write_intr_prst(data, chan->type,
831 						     0, data->ps_period);
832 
833 			if (ret < 0)
834 				ret = ltr501_ps_write_samp_freq(data, freq_val,
835 								freq_val2);
836 			break;
837 		default:
838 			ret = -EINVAL;
839 			break;
840 		}
841 		break;
842 
843 	default:
844 		ret = -EINVAL;
845 		break;
846 	}
847 
848 	iio_device_release_direct_mode(indio_dev);
849 	return ret;
850 }
851 
852 static int ltr501_read_thresh(const struct iio_dev *indio_dev,
853 			      const struct iio_chan_spec *chan,
854 			      enum iio_event_type type,
855 			      enum iio_event_direction dir,
856 			      enum iio_event_info info,
857 			      int *val, int *val2)
858 {
859 	const struct ltr501_data *data = iio_priv(indio_dev);
860 	int ret, thresh_data;
861 
862 	switch (chan->type) {
863 	case IIO_INTENSITY:
864 		switch (dir) {
865 		case IIO_EV_DIR_RISING:
866 			ret = regmap_bulk_read(data->regmap,
867 					       LTR501_ALS_THRESH_UP,
868 					       &thresh_data, 2);
869 			if (ret < 0)
870 				return ret;
871 			*val = thresh_data & LTR501_ALS_THRESH_MASK;
872 			return IIO_VAL_INT;
873 		case IIO_EV_DIR_FALLING:
874 			ret = regmap_bulk_read(data->regmap,
875 					       LTR501_ALS_THRESH_LOW,
876 					       &thresh_data, 2);
877 			if (ret < 0)
878 				return ret;
879 			*val = thresh_data & LTR501_ALS_THRESH_MASK;
880 			return IIO_VAL_INT;
881 		default:
882 			return -EINVAL;
883 		}
884 	case IIO_PROXIMITY:
885 		switch (dir) {
886 		case IIO_EV_DIR_RISING:
887 			ret = regmap_bulk_read(data->regmap,
888 					       LTR501_PS_THRESH_UP,
889 					       &thresh_data, 2);
890 			if (ret < 0)
891 				return ret;
892 			*val = thresh_data & LTR501_PS_THRESH_MASK;
893 			return IIO_VAL_INT;
894 		case IIO_EV_DIR_FALLING:
895 			ret = regmap_bulk_read(data->regmap,
896 					       LTR501_PS_THRESH_LOW,
897 					       &thresh_data, 2);
898 			if (ret < 0)
899 				return ret;
900 			*val = thresh_data & LTR501_PS_THRESH_MASK;
901 			return IIO_VAL_INT;
902 		default:
903 			return -EINVAL;
904 		}
905 	default:
906 		return -EINVAL;
907 	}
908 
909 	return -EINVAL;
910 }
911 
912 static int ltr501_write_thresh(struct iio_dev *indio_dev,
913 			       const struct iio_chan_spec *chan,
914 			       enum iio_event_type type,
915 			       enum iio_event_direction dir,
916 			       enum iio_event_info info,
917 			       int val, int val2)
918 {
919 	struct ltr501_data *data = iio_priv(indio_dev);
920 	int ret;
921 
922 	if (val < 0)
923 		return -EINVAL;
924 
925 	switch (chan->type) {
926 	case IIO_INTENSITY:
927 		if (val > LTR501_ALS_THRESH_MASK)
928 			return -EINVAL;
929 		switch (dir) {
930 		case IIO_EV_DIR_RISING:
931 			mutex_lock(&data->lock_als);
932 			ret = regmap_bulk_write(data->regmap,
933 						LTR501_ALS_THRESH_UP,
934 						&val, 2);
935 			mutex_unlock(&data->lock_als);
936 			return ret;
937 		case IIO_EV_DIR_FALLING:
938 			mutex_lock(&data->lock_als);
939 			ret = regmap_bulk_write(data->regmap,
940 						LTR501_ALS_THRESH_LOW,
941 						&val, 2);
942 			mutex_unlock(&data->lock_als);
943 			return ret;
944 		default:
945 			return -EINVAL;
946 		}
947 	case IIO_PROXIMITY:
948 		if (val > LTR501_PS_THRESH_MASK)
949 			return -EINVAL;
950 		switch (dir) {
951 		case IIO_EV_DIR_RISING:
952 			mutex_lock(&data->lock_ps);
953 			ret = regmap_bulk_write(data->regmap,
954 						LTR501_PS_THRESH_UP,
955 						&val, 2);
956 			mutex_unlock(&data->lock_ps);
957 			return ret;
958 		case IIO_EV_DIR_FALLING:
959 			mutex_lock(&data->lock_ps);
960 			ret = regmap_bulk_write(data->regmap,
961 						LTR501_PS_THRESH_LOW,
962 						&val, 2);
963 			mutex_unlock(&data->lock_ps);
964 			return ret;
965 		default:
966 			return -EINVAL;
967 		}
968 	default:
969 		return -EINVAL;
970 	}
971 
972 	return -EINVAL;
973 }
974 
975 static int ltr501_read_event(struct iio_dev *indio_dev,
976 			     const struct iio_chan_spec *chan,
977 			     enum iio_event_type type,
978 			     enum iio_event_direction dir,
979 			     enum iio_event_info info,
980 			     int *val, int *val2)
981 {
982 	int ret;
983 
984 	switch (info) {
985 	case IIO_EV_INFO_VALUE:
986 		return ltr501_read_thresh(indio_dev, chan, type, dir,
987 					  info, val, val2);
988 	case IIO_EV_INFO_PERIOD:
989 		ret = ltr501_read_intr_prst(iio_priv(indio_dev),
990 					    chan->type, val2);
991 		*val = *val2 / 1000000;
992 		*val2 = *val2 % 1000000;
993 		return ret;
994 	default:
995 		return -EINVAL;
996 	}
997 
998 	return -EINVAL;
999 }
1000 
1001 static int ltr501_write_event(struct iio_dev *indio_dev,
1002 			      const struct iio_chan_spec *chan,
1003 			      enum iio_event_type type,
1004 			      enum iio_event_direction dir,
1005 			      enum iio_event_info info,
1006 			      int val, int val2)
1007 {
1008 	switch (info) {
1009 	case IIO_EV_INFO_VALUE:
1010 		if (val2 != 0)
1011 			return -EINVAL;
1012 		return ltr501_write_thresh(indio_dev, chan, type, dir,
1013 					   info, val, val2);
1014 	case IIO_EV_INFO_PERIOD:
1015 		return ltr501_write_intr_prst(iio_priv(indio_dev), chan->type,
1016 					      val, val2);
1017 	default:
1018 		return -EINVAL;
1019 	}
1020 
1021 	return -EINVAL;
1022 }
1023 
1024 static int ltr501_read_event_config(struct iio_dev *indio_dev,
1025 				    const struct iio_chan_spec *chan,
1026 				    enum iio_event_type type,
1027 				    enum iio_event_direction dir)
1028 {
1029 	struct ltr501_data *data = iio_priv(indio_dev);
1030 	int ret, status;
1031 
1032 	switch (chan->type) {
1033 	case IIO_INTENSITY:
1034 		ret = regmap_field_read(data->reg_als_intr, &status);
1035 		if (ret < 0)
1036 			return ret;
1037 		return status;
1038 	case IIO_PROXIMITY:
1039 		ret = regmap_field_read(data->reg_ps_intr, &status);
1040 		if (ret < 0)
1041 			return ret;
1042 		return status;
1043 	default:
1044 		return -EINVAL;
1045 	}
1046 
1047 	return -EINVAL;
1048 }
1049 
1050 static int ltr501_write_event_config(struct iio_dev *indio_dev,
1051 				     const struct iio_chan_spec *chan,
1052 				     enum iio_event_type type,
1053 				     enum iio_event_direction dir, int state)
1054 {
1055 	struct ltr501_data *data = iio_priv(indio_dev);
1056 	int ret;
1057 
1058 	/* only 1 and 0 are valid inputs */
1059 	if (state != 1  && state != 0)
1060 		return -EINVAL;
1061 
1062 	switch (chan->type) {
1063 	case IIO_INTENSITY:
1064 		mutex_lock(&data->lock_als);
1065 		ret = regmap_field_write(data->reg_als_intr, state);
1066 		mutex_unlock(&data->lock_als);
1067 		return ret;
1068 	case IIO_PROXIMITY:
1069 		mutex_lock(&data->lock_ps);
1070 		ret = regmap_field_write(data->reg_ps_intr, state);
1071 		mutex_unlock(&data->lock_ps);
1072 		return ret;
1073 	default:
1074 		return -EINVAL;
1075 	}
1076 
1077 	return -EINVAL;
1078 }
1079 
1080 static ssize_t ltr501_show_proximity_scale_avail(struct device *dev,
1081 						 struct device_attribute *attr,
1082 						 char *buf)
1083 {
1084 	struct ltr501_data *data = iio_priv(dev_to_iio_dev(dev));
1085 	struct ltr501_chip_info *info = data->chip_info;
1086 	ssize_t len = 0;
1087 	int i;
1088 
1089 	for (i = 0; i < info->ps_gain_tbl_size; i++) {
1090 		if (info->ps_gain[i].scale == LTR501_RESERVED_GAIN)
1091 			continue;
1092 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06d ",
1093 				 info->ps_gain[i].scale,
1094 				 info->ps_gain[i].uscale);
1095 	}
1096 
1097 	buf[len - 1] = '\n';
1098 
1099 	return len;
1100 }
1101 
1102 static ssize_t ltr501_show_intensity_scale_avail(struct device *dev,
1103 						 struct device_attribute *attr,
1104 						 char *buf)
1105 {
1106 	struct ltr501_data *data = iio_priv(dev_to_iio_dev(dev));
1107 	struct ltr501_chip_info *info = data->chip_info;
1108 	ssize_t len = 0;
1109 	int i;
1110 
1111 	for (i = 0; i < info->als_gain_tbl_size; i++) {
1112 		if (info->als_gain[i].scale == LTR501_RESERVED_GAIN)
1113 			continue;
1114 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06d ",
1115 				 info->als_gain[i].scale,
1116 				 info->als_gain[i].uscale);
1117 	}
1118 
1119 	buf[len - 1] = '\n';
1120 
1121 	return len;
1122 }
1123 
1124 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.05 0.1 0.2 0.4");
1125 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("20 10 5 2 1 0.5");
1126 
1127 static IIO_DEVICE_ATTR(in_proximity_scale_available, S_IRUGO,
1128 		       ltr501_show_proximity_scale_avail, NULL, 0);
1129 static IIO_DEVICE_ATTR(in_intensity_scale_available, S_IRUGO,
1130 		       ltr501_show_intensity_scale_avail, NULL, 0);
1131 
1132 static struct attribute *ltr501_attributes[] = {
1133 	&iio_dev_attr_in_proximity_scale_available.dev_attr.attr,
1134 	&iio_dev_attr_in_intensity_scale_available.dev_attr.attr,
1135 	&iio_const_attr_integration_time_available.dev_attr.attr,
1136 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
1137 	NULL
1138 };
1139 
1140 static struct attribute *ltr301_attributes[] = {
1141 	&iio_dev_attr_in_intensity_scale_available.dev_attr.attr,
1142 	&iio_const_attr_integration_time_available.dev_attr.attr,
1143 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
1144 	NULL
1145 };
1146 
1147 static const struct attribute_group ltr501_attribute_group = {
1148 	.attrs = ltr501_attributes,
1149 };
1150 
1151 static const struct attribute_group ltr301_attribute_group = {
1152 	.attrs = ltr301_attributes,
1153 };
1154 
1155 static const struct iio_info ltr501_info_no_irq = {
1156 	.read_raw = ltr501_read_raw,
1157 	.write_raw = ltr501_write_raw,
1158 	.attrs = &ltr501_attribute_group,
1159 };
1160 
1161 static const struct iio_info ltr501_info = {
1162 	.read_raw = ltr501_read_raw,
1163 	.write_raw = ltr501_write_raw,
1164 	.attrs = &ltr501_attribute_group,
1165 	.read_event_value	= &ltr501_read_event,
1166 	.write_event_value	= &ltr501_write_event,
1167 	.read_event_config	= &ltr501_read_event_config,
1168 	.write_event_config	= &ltr501_write_event_config,
1169 };
1170 
1171 static const struct iio_info ltr301_info_no_irq = {
1172 	.read_raw = ltr501_read_raw,
1173 	.write_raw = ltr501_write_raw,
1174 	.attrs = &ltr301_attribute_group,
1175 };
1176 
1177 static const struct iio_info ltr301_info = {
1178 	.read_raw = ltr501_read_raw,
1179 	.write_raw = ltr501_write_raw,
1180 	.attrs = &ltr301_attribute_group,
1181 	.read_event_value	= &ltr501_read_event,
1182 	.write_event_value	= &ltr501_write_event,
1183 	.read_event_config	= &ltr501_read_event_config,
1184 	.write_event_config	= &ltr501_write_event_config,
1185 };
1186 
1187 static struct ltr501_chip_info ltr501_chip_info_tbl[] = {
1188 	[ltr501] = {
1189 		.partid = 0x08,
1190 		.als_gain = ltr501_als_gain_tbl,
1191 		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
1192 		.ps_gain = ltr501_ps_gain_tbl,
1193 		.ps_gain_tbl_size = ARRAY_SIZE(ltr501_ps_gain_tbl),
1194 		.als_mode_active = BIT(0) | BIT(1),
1195 		.als_gain_mask = BIT(3),
1196 		.als_gain_shift = 3,
1197 		.info = &ltr501_info,
1198 		.info_no_irq = &ltr501_info_no_irq,
1199 		.channels = ltr501_channels,
1200 		.no_channels = ARRAY_SIZE(ltr501_channels),
1201 	},
1202 	[ltr559] = {
1203 		.partid = 0x09,
1204 		.als_gain = ltr559_als_gain_tbl,
1205 		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
1206 		.ps_gain = ltr559_ps_gain_tbl,
1207 		.ps_gain_tbl_size = ARRAY_SIZE(ltr559_ps_gain_tbl),
1208 		.als_mode_active = BIT(1),
1209 		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
1210 		.als_gain_shift = 2,
1211 		.info = &ltr501_info,
1212 		.info_no_irq = &ltr501_info_no_irq,
1213 		.channels = ltr501_channels,
1214 		.no_channels = ARRAY_SIZE(ltr501_channels),
1215 	},
1216 	[ltr301] = {
1217 		.partid = 0x08,
1218 		.als_gain = ltr501_als_gain_tbl,
1219 		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
1220 		.als_mode_active = BIT(0) | BIT(1),
1221 		.als_gain_mask = BIT(3),
1222 		.als_gain_shift = 3,
1223 		.info = &ltr301_info,
1224 		.info_no_irq = &ltr301_info_no_irq,
1225 		.channels = ltr301_channels,
1226 		.no_channels = ARRAY_SIZE(ltr301_channels),
1227 	},
1228 };
1229 
1230 static int ltr501_write_contr(struct ltr501_data *data, u8 als_val, u8 ps_val)
1231 {
1232 	int ret;
1233 
1234 	ret = regmap_write(data->regmap, LTR501_ALS_CONTR, als_val);
1235 	if (ret < 0)
1236 		return ret;
1237 
1238 	return regmap_write(data->regmap, LTR501_PS_CONTR, ps_val);
1239 }
1240 
1241 static irqreturn_t ltr501_trigger_handler(int irq, void *p)
1242 {
1243 	struct iio_poll_func *pf = p;
1244 	struct iio_dev *indio_dev = pf->indio_dev;
1245 	struct ltr501_data *data = iio_priv(indio_dev);
1246 	struct {
1247 		u16 channels[3];
1248 		s64 ts __aligned(8);
1249 	} scan;
1250 	__le16 als_buf[2];
1251 	u8 mask = 0;
1252 	int j = 0;
1253 	int ret, psdata;
1254 
1255 	memset(&scan, 0, sizeof(scan));
1256 
1257 	/* figure out which data needs to be ready */
1258 	if (test_bit(0, indio_dev->active_scan_mask) ||
1259 	    test_bit(1, indio_dev->active_scan_mask))
1260 		mask |= LTR501_STATUS_ALS_RDY;
1261 	if (test_bit(2, indio_dev->active_scan_mask))
1262 		mask |= LTR501_STATUS_PS_RDY;
1263 
1264 	ret = ltr501_drdy(data, mask);
1265 	if (ret < 0)
1266 		goto done;
1267 
1268 	if (mask & LTR501_STATUS_ALS_RDY) {
1269 		ret = regmap_bulk_read(data->regmap, LTR501_ALS_DATA1,
1270 				       als_buf, sizeof(als_buf));
1271 		if (ret < 0)
1272 			return ret;
1273 		if (test_bit(0, indio_dev->active_scan_mask))
1274 			scan.channels[j++] = le16_to_cpu(als_buf[1]);
1275 		if (test_bit(1, indio_dev->active_scan_mask))
1276 			scan.channels[j++] = le16_to_cpu(als_buf[0]);
1277 	}
1278 
1279 	if (mask & LTR501_STATUS_PS_RDY) {
1280 		ret = regmap_bulk_read(data->regmap, LTR501_PS_DATA,
1281 				       &psdata, 2);
1282 		if (ret < 0)
1283 			goto done;
1284 		scan.channels[j++] = psdata & LTR501_PS_DATA_MASK;
1285 	}
1286 
1287 	iio_push_to_buffers_with_timestamp(indio_dev, &scan,
1288 					   iio_get_time_ns(indio_dev));
1289 
1290 done:
1291 	iio_trigger_notify_done(indio_dev->trig);
1292 
1293 	return IRQ_HANDLED;
1294 }
1295 
1296 static irqreturn_t ltr501_interrupt_handler(int irq, void *private)
1297 {
1298 	struct iio_dev *indio_dev = private;
1299 	struct ltr501_data *data = iio_priv(indio_dev);
1300 	int ret, status;
1301 
1302 	ret = regmap_read(data->regmap, LTR501_ALS_PS_STATUS, &status);
1303 	if (ret < 0) {
1304 		dev_err(&data->client->dev,
1305 			"irq read int reg failed\n");
1306 		return IRQ_HANDLED;
1307 	}
1308 
1309 	if (status & LTR501_STATUS_ALS_INTR)
1310 		iio_push_event(indio_dev,
1311 			       IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
1312 						    IIO_EV_TYPE_THRESH,
1313 						    IIO_EV_DIR_EITHER),
1314 			       iio_get_time_ns(indio_dev));
1315 
1316 	if (status & LTR501_STATUS_PS_INTR)
1317 		iio_push_event(indio_dev,
1318 			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
1319 						    IIO_EV_TYPE_THRESH,
1320 						    IIO_EV_DIR_EITHER),
1321 			       iio_get_time_ns(indio_dev));
1322 
1323 	return IRQ_HANDLED;
1324 }
1325 
1326 static int ltr501_init(struct ltr501_data *data)
1327 {
1328 	int ret, status;
1329 
1330 	ret = regmap_read(data->regmap, LTR501_ALS_CONTR, &status);
1331 	if (ret < 0)
1332 		return ret;
1333 
1334 	data->als_contr = status | data->chip_info->als_mode_active;
1335 
1336 	ret = regmap_read(data->regmap, LTR501_PS_CONTR, &status);
1337 	if (ret < 0)
1338 		return ret;
1339 
1340 	data->ps_contr = status | LTR501_CONTR_ACTIVE;
1341 
1342 	ret = ltr501_read_intr_prst(data, IIO_INTENSITY, &data->als_period);
1343 	if (ret < 0)
1344 		return ret;
1345 
1346 	ret = ltr501_read_intr_prst(data, IIO_PROXIMITY, &data->ps_period);
1347 	if (ret < 0)
1348 		return ret;
1349 
1350 	return ltr501_write_contr(data, data->als_contr, data->ps_contr);
1351 }
1352 
1353 static bool ltr501_is_volatile_reg(struct device *dev, unsigned int reg)
1354 {
1355 	switch (reg) {
1356 	case LTR501_ALS_DATA1:
1357 	case LTR501_ALS_DATA0:
1358 	case LTR501_ALS_PS_STATUS:
1359 	case LTR501_PS_DATA:
1360 		return true;
1361 	default:
1362 		return false;
1363 	}
1364 }
1365 
1366 static const struct regmap_config ltr501_regmap_config = {
1367 	.name =  LTR501_REGMAP_NAME,
1368 	.reg_bits = 8,
1369 	.val_bits = 8,
1370 	.max_register = LTR501_MAX_REG,
1371 	.cache_type = REGCACHE_RBTREE,
1372 	.volatile_reg = ltr501_is_volatile_reg,
1373 };
1374 
1375 static int ltr501_powerdown(struct ltr501_data *data)
1376 {
1377 	return ltr501_write_contr(data, data->als_contr &
1378 				  ~data->chip_info->als_mode_active,
1379 				  data->ps_contr & ~LTR501_CONTR_ACTIVE);
1380 }
1381 
1382 static const char *ltr501_match_acpi_device(struct device *dev, int *chip_idx)
1383 {
1384 	const struct acpi_device_id *id;
1385 
1386 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
1387 	if (!id)
1388 		return NULL;
1389 	*chip_idx = id->driver_data;
1390 	return dev_name(dev);
1391 }
1392 
1393 static int ltr501_probe(struct i2c_client *client,
1394 			const struct i2c_device_id *id)
1395 {
1396 	struct ltr501_data *data;
1397 	struct iio_dev *indio_dev;
1398 	struct regmap *regmap;
1399 	int ret, partid, chip_idx = 0;
1400 	const char *name = NULL;
1401 
1402 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
1403 	if (!indio_dev)
1404 		return -ENOMEM;
1405 
1406 	regmap = devm_regmap_init_i2c(client, &ltr501_regmap_config);
1407 	if (IS_ERR(regmap)) {
1408 		dev_err(&client->dev, "Regmap initialization failed.\n");
1409 		return PTR_ERR(regmap);
1410 	}
1411 
1412 	data = iio_priv(indio_dev);
1413 	i2c_set_clientdata(client, indio_dev);
1414 	data->client = client;
1415 	data->regmap = regmap;
1416 	mutex_init(&data->lock_als);
1417 	mutex_init(&data->lock_ps);
1418 
1419 	data->reg_it = devm_regmap_field_alloc(&client->dev, regmap,
1420 					       reg_field_it);
1421 	if (IS_ERR(data->reg_it)) {
1422 		dev_err(&client->dev, "Integ time reg field init failed.\n");
1423 		return PTR_ERR(data->reg_it);
1424 	}
1425 
1426 	data->reg_als_intr = devm_regmap_field_alloc(&client->dev, regmap,
1427 						     reg_field_als_intr);
1428 	if (IS_ERR(data->reg_als_intr)) {
1429 		dev_err(&client->dev, "ALS intr mode reg field init failed\n");
1430 		return PTR_ERR(data->reg_als_intr);
1431 	}
1432 
1433 	data->reg_ps_intr = devm_regmap_field_alloc(&client->dev, regmap,
1434 						    reg_field_ps_intr);
1435 	if (IS_ERR(data->reg_ps_intr)) {
1436 		dev_err(&client->dev, "PS intr mode reg field init failed.\n");
1437 		return PTR_ERR(data->reg_ps_intr);
1438 	}
1439 
1440 	data->reg_als_rate = devm_regmap_field_alloc(&client->dev, regmap,
1441 						     reg_field_als_rate);
1442 	if (IS_ERR(data->reg_als_rate)) {
1443 		dev_err(&client->dev, "ALS samp rate field init failed.\n");
1444 		return PTR_ERR(data->reg_als_rate);
1445 	}
1446 
1447 	data->reg_ps_rate = devm_regmap_field_alloc(&client->dev, regmap,
1448 						    reg_field_ps_rate);
1449 	if (IS_ERR(data->reg_ps_rate)) {
1450 		dev_err(&client->dev, "PS samp rate field init failed.\n");
1451 		return PTR_ERR(data->reg_ps_rate);
1452 	}
1453 
1454 	data->reg_als_prst = devm_regmap_field_alloc(&client->dev, regmap,
1455 						     reg_field_als_prst);
1456 	if (IS_ERR(data->reg_als_prst)) {
1457 		dev_err(&client->dev, "ALS prst reg field init failed\n");
1458 		return PTR_ERR(data->reg_als_prst);
1459 	}
1460 
1461 	data->reg_ps_prst = devm_regmap_field_alloc(&client->dev, regmap,
1462 						    reg_field_ps_prst);
1463 	if (IS_ERR(data->reg_ps_prst)) {
1464 		dev_err(&client->dev, "PS prst reg field init failed.\n");
1465 		return PTR_ERR(data->reg_ps_prst);
1466 	}
1467 
1468 	ret = regmap_read(data->regmap, LTR501_PART_ID, &partid);
1469 	if (ret < 0)
1470 		return ret;
1471 
1472 	if (id) {
1473 		name = id->name;
1474 		chip_idx = id->driver_data;
1475 	} else  if (ACPI_HANDLE(&client->dev)) {
1476 		name = ltr501_match_acpi_device(&client->dev, &chip_idx);
1477 	} else {
1478 		return -ENODEV;
1479 	}
1480 
1481 	data->chip_info = &ltr501_chip_info_tbl[chip_idx];
1482 
1483 	if ((partid >> 4) != data->chip_info->partid)
1484 		return -ENODEV;
1485 
1486 	indio_dev->info = data->chip_info->info;
1487 	indio_dev->channels = data->chip_info->channels;
1488 	indio_dev->num_channels = data->chip_info->no_channels;
1489 	indio_dev->name = name;
1490 	indio_dev->modes = INDIO_DIRECT_MODE;
1491 
1492 	ret = ltr501_init(data);
1493 	if (ret < 0)
1494 		return ret;
1495 
1496 	if (client->irq > 0) {
1497 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1498 						NULL, ltr501_interrupt_handler,
1499 						IRQF_TRIGGER_FALLING |
1500 						IRQF_ONESHOT,
1501 						"ltr501_thresh_event",
1502 						indio_dev);
1503 		if (ret) {
1504 			dev_err(&client->dev, "request irq (%d) failed\n",
1505 				client->irq);
1506 			return ret;
1507 		}
1508 	} else {
1509 		indio_dev->info = data->chip_info->info_no_irq;
1510 	}
1511 
1512 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
1513 					 ltr501_trigger_handler, NULL);
1514 	if (ret)
1515 		goto powerdown_on_error;
1516 
1517 	ret = iio_device_register(indio_dev);
1518 	if (ret)
1519 		goto error_unreg_buffer;
1520 
1521 	return 0;
1522 
1523 error_unreg_buffer:
1524 	iio_triggered_buffer_cleanup(indio_dev);
1525 powerdown_on_error:
1526 	ltr501_powerdown(data);
1527 	return ret;
1528 }
1529 
1530 static int ltr501_remove(struct i2c_client *client)
1531 {
1532 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
1533 
1534 	iio_device_unregister(indio_dev);
1535 	iio_triggered_buffer_cleanup(indio_dev);
1536 	ltr501_powerdown(iio_priv(indio_dev));
1537 
1538 	return 0;
1539 }
1540 
1541 #ifdef CONFIG_PM_SLEEP
1542 static int ltr501_suspend(struct device *dev)
1543 {
1544 	struct ltr501_data *data = iio_priv(i2c_get_clientdata(
1545 					    to_i2c_client(dev)));
1546 	return ltr501_powerdown(data);
1547 }
1548 
1549 static int ltr501_resume(struct device *dev)
1550 {
1551 	struct ltr501_data *data = iio_priv(i2c_get_clientdata(
1552 					    to_i2c_client(dev)));
1553 
1554 	return ltr501_write_contr(data, data->als_contr,
1555 		data->ps_contr);
1556 }
1557 #endif
1558 
1559 static SIMPLE_DEV_PM_OPS(ltr501_pm_ops, ltr501_suspend, ltr501_resume);
1560 
1561 static const struct acpi_device_id ltr_acpi_match[] = {
1562 	{"LTER0501", ltr501},
1563 	{"LTER0559", ltr559},
1564 	{"LTER0301", ltr301},
1565 	{ },
1566 };
1567 MODULE_DEVICE_TABLE(acpi, ltr_acpi_match);
1568 
1569 static const struct i2c_device_id ltr501_id[] = {
1570 	{ "ltr501", ltr501},
1571 	{ "ltr559", ltr559},
1572 	{ "ltr301", ltr301},
1573 	{ }
1574 };
1575 MODULE_DEVICE_TABLE(i2c, ltr501_id);
1576 
1577 static struct i2c_driver ltr501_driver = {
1578 	.driver = {
1579 		.name   = LTR501_DRV_NAME,
1580 		.pm	= &ltr501_pm_ops,
1581 		.acpi_match_table = ACPI_PTR(ltr_acpi_match),
1582 	},
1583 	.probe  = ltr501_probe,
1584 	.remove	= ltr501_remove,
1585 	.id_table = ltr501_id,
1586 };
1587 
1588 module_i2c_driver(ltr501_driver);
1589 
1590 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
1591 MODULE_DESCRIPTION("Lite-On LTR501 ambient light and proximity sensor driver");
1592 MODULE_LICENSE("GPL");
1593