xref: /linux/drivers/iio/light/isl29018.c (revision 4e0ae876f77bc01a7e77724dea57b4b82bd53244)
1 /*
2  * A iio driver for the light sensor ISL 29018/29023/29035.
3  *
4  * IIO driver for monitoring ambient light intensity in luxi, proximity
5  * sensing and infrared sensing.
6  *
7  * Copyright (c) 2010, NVIDIA Corporation.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/i2c.h>
22 #include <linux/err.h>
23 #include <linux/mutex.h>
24 #include <linux/delay.h>
25 #include <linux/regmap.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/slab.h>
28 #include <linux/iio/iio.h>
29 #include <linux/iio/sysfs.h>
30 #include <linux/acpi.h>
31 
32 #define ISL29018_CONV_TIME_MS		100
33 
34 #define ISL29018_REG_ADD_COMMAND1	0x00
35 #define ISL29018_CMD1_OPMODE_SHIFT	5
36 #define ISL29018_CMD1_OPMODE_MASK	(7 << ISL29018_CMD1_OPMODE_SHIFT)
37 #define ISL29018_CMD1_OPMODE_POWER_DOWN	0
38 #define ISL29018_CMD1_OPMODE_ALS_ONCE	1
39 #define ISL29018_CMD1_OPMODE_IR_ONCE	2
40 #define ISL29018_CMD1_OPMODE_PROX_ONCE	3
41 
42 #define ISL29018_REG_ADD_COMMAND2	0x01
43 #define ISL29018_CMD2_RESOLUTION_SHIFT	2
44 #define ISL29018_CMD2_RESOLUTION_MASK	(0x3 << ISL29018_CMD2_RESOLUTION_SHIFT)
45 
46 #define ISL29018_CMD2_RANGE_SHIFT	0
47 #define ISL29018_CMD2_RANGE_MASK	(0x3 << ISL29018_CMD2_RANGE_SHIFT)
48 
49 #define ISL29018_CMD2_SCHEME_SHIFT	7
50 #define ISL29018_CMD2_SCHEME_MASK	(0x1 << ISL29018_CMD2_SCHEME_SHIFT)
51 
52 #define ISL29018_REG_ADD_DATA_LSB	0x02
53 #define ISL29018_REG_ADD_DATA_MSB	0x03
54 
55 #define ISL29018_REG_TEST		0x08
56 #define ISL29018_TEST_SHIFT		0
57 #define ISL29018_TEST_MASK		(0xFF << ISL29018_TEST_SHIFT)
58 
59 #define ISL29035_REG_DEVICE_ID		0x0F
60 #define ISL29035_DEVICE_ID_SHIFT	0x03
61 #define ISL29035_DEVICE_ID_MASK		(0x7 << ISL29035_DEVICE_ID_SHIFT)
62 #define ISL29035_DEVICE_ID		0x5
63 #define ISL29035_BOUT_SHIFT		0x07
64 #define ISL29035_BOUT_MASK		(0x01 << ISL29035_BOUT_SHIFT)
65 
66 enum isl29018_int_time {
67 	ISL29018_INT_TIME_16,
68 	ISL29018_INT_TIME_12,
69 	ISL29018_INT_TIME_8,
70 	ISL29018_INT_TIME_4,
71 };
72 
73 static const unsigned int isl29018_int_utimes[3][4] = {
74 	{90000, 5630, 351, 21},
75 	{90000, 5600, 352, 22},
76 	{105000, 6500, 410, 25},
77 };
78 
79 static const struct isl29018_scale {
80 	unsigned int scale;
81 	unsigned int uscale;
82 } isl29018_scales[4][4] = {
83 	{ {0, 15258}, {0, 61035}, {0, 244140}, {0, 976562} },
84 	{ {0, 244140}, {0, 976562}, {3, 906250}, {15, 625000} },
85 	{ {3, 906250}, {15, 625000}, {62, 500000}, {250, 0} },
86 	{ {62, 500000}, {250, 0}, {1000, 0}, {4000, 0} }
87 };
88 
89 struct isl29018_chip {
90 	struct regmap		*regmap;
91 	struct mutex		lock;
92 	int			type;
93 	unsigned int		calibscale;
94 	unsigned int		ucalibscale;
95 	unsigned int		int_time;
96 	struct isl29018_scale	scale;
97 	int			prox_scheme;
98 	bool			suspended;
99 	struct regulator	*vcc_reg;
100 };
101 
102 static int isl29018_set_integration_time(struct isl29018_chip *chip,
103 					 unsigned int utime)
104 {
105 	unsigned int i;
106 	int ret;
107 	unsigned int int_time, new_int_time;
108 
109 	for (i = 0; i < ARRAY_SIZE(isl29018_int_utimes[chip->type]); ++i) {
110 		if (utime == isl29018_int_utimes[chip->type][i]) {
111 			new_int_time = i;
112 			break;
113 		}
114 	}
115 
116 	if (i >= ARRAY_SIZE(isl29018_int_utimes[chip->type]))
117 		return -EINVAL;
118 
119 	ret = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
120 				 ISL29018_CMD2_RESOLUTION_MASK,
121 				 i << ISL29018_CMD2_RESOLUTION_SHIFT);
122 	if (ret < 0)
123 		return ret;
124 
125 	/* Keep the same range when integration time changes */
126 	int_time = chip->int_time;
127 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[int_time]); ++i) {
128 		if (chip->scale.scale == isl29018_scales[int_time][i].scale &&
129 		    chip->scale.uscale == isl29018_scales[int_time][i].uscale) {
130 			chip->scale = isl29018_scales[new_int_time][i];
131 			break;
132 		}
133 	}
134 	chip->int_time = new_int_time;
135 
136 	return 0;
137 }
138 
139 static int isl29018_set_scale(struct isl29018_chip *chip, int scale, int uscale)
140 {
141 	unsigned int i;
142 	int ret;
143 	struct isl29018_scale new_scale;
144 
145 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[chip->int_time]); ++i) {
146 		if (scale == isl29018_scales[chip->int_time][i].scale &&
147 		    uscale == isl29018_scales[chip->int_time][i].uscale) {
148 			new_scale = isl29018_scales[chip->int_time][i];
149 			break;
150 		}
151 	}
152 
153 	if (i >= ARRAY_SIZE(isl29018_scales[chip->int_time]))
154 		return -EINVAL;
155 
156 	ret = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
157 				 ISL29018_CMD2_RANGE_MASK,
158 				 i << ISL29018_CMD2_RANGE_SHIFT);
159 	if (ret < 0)
160 		return ret;
161 
162 	chip->scale = new_scale;
163 
164 	return 0;
165 }
166 
167 static int isl29018_read_sensor_input(struct isl29018_chip *chip, int mode)
168 {
169 	int status;
170 	unsigned int lsb;
171 	unsigned int msb;
172 	struct device *dev = regmap_get_device(chip->regmap);
173 
174 	/* Set mode */
175 	status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1,
176 			      mode << ISL29018_CMD1_OPMODE_SHIFT);
177 	if (status) {
178 		dev_err(dev,
179 			"Error in setting operating mode err %d\n", status);
180 		return status;
181 	}
182 	msleep(ISL29018_CONV_TIME_MS);
183 	status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_LSB, &lsb);
184 	if (status < 0) {
185 		dev_err(dev,
186 			"Error in reading LSB DATA with err %d\n", status);
187 		return status;
188 	}
189 
190 	status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_MSB, &msb);
191 	if (status < 0) {
192 		dev_err(dev,
193 			"Error in reading MSB DATA with error %d\n", status);
194 		return status;
195 	}
196 	dev_vdbg(dev, "MSB 0x%x and LSB 0x%x\n", msb, lsb);
197 
198 	return (msb << 8) | lsb;
199 }
200 
201 static int isl29018_read_lux(struct isl29018_chip *chip, int *lux)
202 {
203 	int lux_data;
204 	unsigned int data_x_range;
205 
206 	lux_data = isl29018_read_sensor_input(chip,
207 					      ISL29018_CMD1_OPMODE_ALS_ONCE);
208 	if (lux_data < 0)
209 		return lux_data;
210 
211 	data_x_range = lux_data * chip->scale.scale +
212 		       lux_data * chip->scale.uscale / 1000000;
213 	*lux = data_x_range * chip->calibscale +
214 	       data_x_range * chip->ucalibscale / 1000000;
215 
216 	return 0;
217 }
218 
219 static int isl29018_read_ir(struct isl29018_chip *chip, int *ir)
220 {
221 	int ir_data;
222 
223 	ir_data = isl29018_read_sensor_input(chip,
224 					     ISL29018_CMD1_OPMODE_IR_ONCE);
225 	if (ir_data < 0)
226 		return ir_data;
227 
228 	*ir = ir_data;
229 
230 	return 0;
231 }
232 
233 static int isl29018_read_proximity_ir(struct isl29018_chip *chip, int scheme,
234 				      int *near_ir)
235 {
236 	int status;
237 	int prox_data = -1;
238 	int ir_data = -1;
239 	struct device *dev = regmap_get_device(chip->regmap);
240 
241 	/* Do proximity sensing with required scheme */
242 	status = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
243 				    ISL29018_CMD2_SCHEME_MASK,
244 				    scheme << ISL29018_CMD2_SCHEME_SHIFT);
245 	if (status) {
246 		dev_err(dev, "Error in setting operating mode\n");
247 		return status;
248 	}
249 
250 	prox_data = isl29018_read_sensor_input(chip,
251 					       ISL29018_CMD1_OPMODE_PROX_ONCE);
252 	if (prox_data < 0)
253 		return prox_data;
254 
255 	if (scheme == 1) {
256 		*near_ir = prox_data;
257 		return 0;
258 	}
259 
260 	ir_data = isl29018_read_sensor_input(chip,
261 					     ISL29018_CMD1_OPMODE_IR_ONCE);
262 	if (ir_data < 0)
263 		return ir_data;
264 
265 	if (prox_data >= ir_data)
266 		*near_ir = prox_data - ir_data;
267 	else
268 		*near_ir = 0;
269 
270 	return 0;
271 }
272 
273 static ssize_t in_illuminance_scale_available_show
274 			(struct device *dev, struct device_attribute *attr,
275 			 char *buf)
276 {
277 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
278 	struct isl29018_chip *chip = iio_priv(indio_dev);
279 	unsigned int i;
280 	int len = 0;
281 
282 	mutex_lock(&chip->lock);
283 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[chip->int_time]); ++i)
284 		len += sprintf(buf + len, "%d.%06d ",
285 			       isl29018_scales[chip->int_time][i].scale,
286 			       isl29018_scales[chip->int_time][i].uscale);
287 	mutex_unlock(&chip->lock);
288 
289 	buf[len - 1] = '\n';
290 
291 	return len;
292 }
293 
294 static ssize_t in_illuminance_integration_time_available_show
295 			(struct device *dev, struct device_attribute *attr,
296 			 char *buf)
297 {
298 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
299 	struct isl29018_chip *chip = iio_priv(indio_dev);
300 	unsigned int i;
301 	int len = 0;
302 
303 	for (i = 0; i < ARRAY_SIZE(isl29018_int_utimes[chip->type]); ++i)
304 		len += sprintf(buf + len, "0.%06d ",
305 			       isl29018_int_utimes[chip->type][i]);
306 
307 	buf[len - 1] = '\n';
308 
309 	return len;
310 }
311 
312 /*
313  * From ISL29018 Data Sheet (FN6619.4, Oct 8, 2012) regarding the
314  * infrared suppression:
315  *
316  *   Proximity Sensing Scheme: Bit 7. This bit programs the function
317  * of the proximity detection. Logic 0 of this bit, Scheme 0, makes
318  * full n (4, 8, 12, 16) bits (unsigned) proximity detection. The range
319  * of Scheme 0 proximity count is from 0 to 2^n. Logic 1 of this bit,
320  * Scheme 1, makes n-1 (3, 7, 11, 15) bits (2's complementary)
321  * proximity_less_ambient detection. The range of Scheme 1
322  * proximity count is from -2^(n-1) to 2^(n-1) . The sign bit is extended
323  * for resolutions less than 16. While Scheme 0 has wider dynamic
324  * range, Scheme 1 proximity detection is less affected by the
325  * ambient IR noise variation.
326  *
327  * 0 Sensing IR from LED and ambient
328  * 1 Sensing IR from LED with ambient IR rejection
329  */
330 static ssize_t proximity_on_chip_ambient_infrared_suppression_show
331 			(struct device *dev, struct device_attribute *attr,
332 			 char *buf)
333 {
334 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
335 	struct isl29018_chip *chip = iio_priv(indio_dev);
336 
337 	/*
338 	 * Return the "proximity scheme" i.e. if the chip does on chip
339 	 * infrared suppression (1 means perform on chip suppression)
340 	 */
341 	return sprintf(buf, "%d\n", chip->prox_scheme);
342 }
343 
344 static ssize_t proximity_on_chip_ambient_infrared_suppression_store
345 			(struct device *dev, struct device_attribute *attr,
346 			 const char *buf, size_t count)
347 {
348 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
349 	struct isl29018_chip *chip = iio_priv(indio_dev);
350 	int val;
351 
352 	if (kstrtoint(buf, 10, &val))
353 		return -EINVAL;
354 	if (!(val == 0 || val == 1))
355 		return -EINVAL;
356 
357 	/*
358 	 * Get the "proximity scheme" i.e. if the chip does on chip
359 	 * infrared suppression (1 means perform on chip suppression)
360 	 */
361 	mutex_lock(&chip->lock);
362 	chip->prox_scheme = val;
363 	mutex_unlock(&chip->lock);
364 
365 	return count;
366 }
367 
368 static int isl29018_write_raw(struct iio_dev *indio_dev,
369 			      struct iio_chan_spec const *chan,
370 			      int val,
371 			      int val2,
372 			      long mask)
373 {
374 	struct isl29018_chip *chip = iio_priv(indio_dev);
375 	int ret = -EINVAL;
376 
377 	mutex_lock(&chip->lock);
378 	if (chip->suspended) {
379 		ret = -EBUSY;
380 		goto write_done;
381 	}
382 	switch (mask) {
383 	case IIO_CHAN_INFO_CALIBSCALE:
384 		if (chan->type == IIO_LIGHT) {
385 			chip->calibscale = val;
386 			chip->ucalibscale = val2;
387 			ret = 0;
388 		}
389 		break;
390 	case IIO_CHAN_INFO_INT_TIME:
391 		if (chan->type == IIO_LIGHT && !val)
392 			ret = isl29018_set_integration_time(chip, val2);
393 		break;
394 	case IIO_CHAN_INFO_SCALE:
395 		if (chan->type == IIO_LIGHT)
396 			ret = isl29018_set_scale(chip, val, val2);
397 		break;
398 	default:
399 		break;
400 	}
401 
402 write_done:
403 	mutex_unlock(&chip->lock);
404 
405 	return ret;
406 }
407 
408 static int isl29018_read_raw(struct iio_dev *indio_dev,
409 			     struct iio_chan_spec const *chan,
410 			     int *val,
411 			     int *val2,
412 			     long mask)
413 {
414 	int ret = -EINVAL;
415 	struct isl29018_chip *chip = iio_priv(indio_dev);
416 
417 	mutex_lock(&chip->lock);
418 	if (chip->suspended) {
419 		ret = -EBUSY;
420 		goto read_done;
421 	}
422 	switch (mask) {
423 	case IIO_CHAN_INFO_RAW:
424 	case IIO_CHAN_INFO_PROCESSED:
425 		switch (chan->type) {
426 		case IIO_LIGHT:
427 			ret = isl29018_read_lux(chip, val);
428 			break;
429 		case IIO_INTENSITY:
430 			ret = isl29018_read_ir(chip, val);
431 			break;
432 		case IIO_PROXIMITY:
433 			ret = isl29018_read_proximity_ir(chip,
434 							 chip->prox_scheme,
435 							 val);
436 			break;
437 		default:
438 			break;
439 		}
440 		if (!ret)
441 			ret = IIO_VAL_INT;
442 		break;
443 	case IIO_CHAN_INFO_INT_TIME:
444 		if (chan->type == IIO_LIGHT) {
445 			*val = 0;
446 			*val2 = isl29018_int_utimes[chip->type][chip->int_time];
447 			ret = IIO_VAL_INT_PLUS_MICRO;
448 		}
449 		break;
450 	case IIO_CHAN_INFO_SCALE:
451 		if (chan->type == IIO_LIGHT) {
452 			*val = chip->scale.scale;
453 			*val2 = chip->scale.uscale;
454 			ret = IIO_VAL_INT_PLUS_MICRO;
455 		}
456 		break;
457 	case IIO_CHAN_INFO_CALIBSCALE:
458 		if (chan->type == IIO_LIGHT) {
459 			*val = chip->calibscale;
460 			*val2 = chip->ucalibscale;
461 			ret = IIO_VAL_INT_PLUS_MICRO;
462 		}
463 		break;
464 	default:
465 		break;
466 	}
467 
468 read_done:
469 	mutex_unlock(&chip->lock);
470 
471 	return ret;
472 }
473 
474 #define ISL29018_LIGHT_CHANNEL {					\
475 	.type = IIO_LIGHT,						\
476 	.indexed = 1,							\
477 	.channel = 0,							\
478 	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |		\
479 	BIT(IIO_CHAN_INFO_CALIBSCALE) |					\
480 	BIT(IIO_CHAN_INFO_SCALE) |					\
481 	BIT(IIO_CHAN_INFO_INT_TIME),					\
482 }
483 
484 #define ISL29018_IR_CHANNEL {						\
485 	.type = IIO_INTENSITY,						\
486 	.modified = 1,							\
487 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
488 	.channel2 = IIO_MOD_LIGHT_IR,					\
489 }
490 
491 #define ISL29018_PROXIMITY_CHANNEL {					\
492 	.type = IIO_PROXIMITY,						\
493 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
494 }
495 
496 static const struct iio_chan_spec isl29018_channels[] = {
497 	ISL29018_LIGHT_CHANNEL,
498 	ISL29018_IR_CHANNEL,
499 	ISL29018_PROXIMITY_CHANNEL,
500 };
501 
502 static const struct iio_chan_spec isl29023_channels[] = {
503 	ISL29018_LIGHT_CHANNEL,
504 	ISL29018_IR_CHANNEL,
505 };
506 
507 static IIO_DEVICE_ATTR_RO(in_illuminance_integration_time_available, 0);
508 static IIO_DEVICE_ATTR_RO(in_illuminance_scale_available, 0);
509 static IIO_DEVICE_ATTR_RW(proximity_on_chip_ambient_infrared_suppression, 0);
510 
511 #define ISL29018_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
512 
513 static struct attribute *isl29018_attributes[] = {
514 	ISL29018_DEV_ATTR(in_illuminance_scale_available),
515 	ISL29018_DEV_ATTR(in_illuminance_integration_time_available),
516 	ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_suppression),
517 	NULL
518 };
519 
520 static struct attribute *isl29023_attributes[] = {
521 	ISL29018_DEV_ATTR(in_illuminance_scale_available),
522 	ISL29018_DEV_ATTR(in_illuminance_integration_time_available),
523 	NULL
524 };
525 
526 static const struct attribute_group isl29018_group = {
527 	.attrs = isl29018_attributes,
528 };
529 
530 static const struct attribute_group isl29023_group = {
531 	.attrs = isl29023_attributes,
532 };
533 
534 enum {
535 	isl29018,
536 	isl29023,
537 	isl29035,
538 };
539 
540 static int isl29018_chip_init(struct isl29018_chip *chip)
541 {
542 	int status;
543 	struct device *dev = regmap_get_device(chip->regmap);
544 
545 	if (chip->type == isl29035) {
546 		unsigned int id;
547 
548 		status = regmap_read(chip->regmap, ISL29035_REG_DEVICE_ID, &id);
549 		if (status < 0) {
550 			dev_err(dev,
551 				"Error reading ID register with error %d\n",
552 				status);
553 			return status;
554 		}
555 
556 		id = (id & ISL29035_DEVICE_ID_MASK) >> ISL29035_DEVICE_ID_SHIFT;
557 
558 		if (id != ISL29035_DEVICE_ID)
559 			return -ENODEV;
560 
561 		/* Clear brownout bit */
562 		status = regmap_update_bits(chip->regmap,
563 					    ISL29035_REG_DEVICE_ID,
564 					    ISL29035_BOUT_MASK, 0);
565 		if (status < 0)
566 			return status;
567 	}
568 
569 	/*
570 	 * Code added per Intersil Application Note 1534:
571 	 *     When VDD sinks to approximately 1.8V or below, some of
572 	 * the part's registers may change their state. When VDD
573 	 * recovers to 2.25V (or greater), the part may thus be in an
574 	 * unknown mode of operation. The user can return the part to
575 	 * a known mode of operation either by (a) setting VDD = 0V for
576 	 * 1 second or more and then powering back up with a slew rate
577 	 * of 0.5V/ms or greater, or (b) via I2C disable all ALS/PROX
578 	 * conversions, clear the test registers, and then rewrite all
579 	 * registers to the desired values.
580 	 * ...
581 	 * For ISL29011, ISL29018, ISL29021, ISL29023
582 	 * 1. Write 0x00 to register 0x08 (TEST)
583 	 * 2. Write 0x00 to register 0x00 (CMD1)
584 	 * 3. Rewrite all registers to the desired values
585 	 *
586 	 * ISL29018 Data Sheet (FN6619.1, Feb 11, 2010) essentially says
587 	 * the same thing EXCEPT the data sheet asks for a 1ms delay after
588 	 * writing the CMD1 register.
589 	 */
590 	status = regmap_write(chip->regmap, ISL29018_REG_TEST, 0x0);
591 	if (status < 0) {
592 		dev_err(dev, "Failed to clear isl29018 TEST reg.(%d)\n",
593 			status);
594 		return status;
595 	}
596 
597 	/*
598 	 * See Intersil AN1534 comments above.
599 	 * "Operating Mode" (COMMAND1) register is reprogrammed when
600 	 * data is read from the device.
601 	 */
602 	status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1, 0);
603 	if (status < 0) {
604 		dev_err(dev, "Failed to clear isl29018 CMD1 reg.(%d)\n",
605 			status);
606 		return status;
607 	}
608 
609 	usleep_range(1000, 2000);	/* per data sheet, page 10 */
610 
611 	/* Set defaults */
612 	status = isl29018_set_scale(chip, chip->scale.scale,
613 				    chip->scale.uscale);
614 	if (status < 0) {
615 		dev_err(dev, "Init of isl29018 fails\n");
616 		return status;
617 	}
618 
619 	status = isl29018_set_integration_time(chip,
620 			isl29018_int_utimes[chip->type][chip->int_time]);
621 	if (status < 0)
622 		dev_err(dev, "Init of isl29018 fails\n");
623 
624 	return status;
625 }
626 
627 static const struct iio_info isl29018_info = {
628 	.attrs = &isl29018_group,
629 	.read_raw = isl29018_read_raw,
630 	.write_raw = isl29018_write_raw,
631 };
632 
633 static const struct iio_info isl29023_info = {
634 	.attrs = &isl29023_group,
635 	.read_raw = isl29018_read_raw,
636 	.write_raw = isl29018_write_raw,
637 };
638 
639 static bool isl29018_is_volatile_reg(struct device *dev, unsigned int reg)
640 {
641 	switch (reg) {
642 	case ISL29018_REG_ADD_DATA_LSB:
643 	case ISL29018_REG_ADD_DATA_MSB:
644 	case ISL29018_REG_ADD_COMMAND1:
645 	case ISL29018_REG_TEST:
646 	case ISL29035_REG_DEVICE_ID:
647 		return true;
648 	default:
649 		return false;
650 	}
651 }
652 
653 static const struct regmap_config isl29018_regmap_config = {
654 	.reg_bits = 8,
655 	.val_bits = 8,
656 	.volatile_reg = isl29018_is_volatile_reg,
657 	.max_register = ISL29018_REG_TEST,
658 	.num_reg_defaults_raw = ISL29018_REG_TEST + 1,
659 	.cache_type = REGCACHE_RBTREE,
660 };
661 
662 static const struct regmap_config isl29035_regmap_config = {
663 	.reg_bits = 8,
664 	.val_bits = 8,
665 	.volatile_reg = isl29018_is_volatile_reg,
666 	.max_register = ISL29035_REG_DEVICE_ID,
667 	.num_reg_defaults_raw = ISL29035_REG_DEVICE_ID + 1,
668 	.cache_type = REGCACHE_RBTREE,
669 };
670 
671 struct isl29018_chip_info {
672 	const struct iio_chan_spec *channels;
673 	int num_channels;
674 	const struct iio_info *indio_info;
675 	const struct regmap_config *regmap_cfg;
676 };
677 
678 static const struct isl29018_chip_info isl29018_chip_info_tbl[] = {
679 	[isl29018] = {
680 		.channels = isl29018_channels,
681 		.num_channels = ARRAY_SIZE(isl29018_channels),
682 		.indio_info = &isl29018_info,
683 		.regmap_cfg = &isl29018_regmap_config,
684 	},
685 	[isl29023] = {
686 		.channels = isl29023_channels,
687 		.num_channels = ARRAY_SIZE(isl29023_channels),
688 		.indio_info = &isl29023_info,
689 		.regmap_cfg = &isl29018_regmap_config,
690 	},
691 	[isl29035] = {
692 		.channels = isl29023_channels,
693 		.num_channels = ARRAY_SIZE(isl29023_channels),
694 		.indio_info = &isl29023_info,
695 		.regmap_cfg = &isl29035_regmap_config,
696 	},
697 };
698 
699 static const char *isl29018_match_acpi_device(struct device *dev, int *data)
700 {
701 	const struct acpi_device_id *id;
702 
703 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
704 
705 	if (!id)
706 		return NULL;
707 
708 	*data = (int)id->driver_data;
709 
710 	return dev_name(dev);
711 }
712 
713 static void isl29018_disable_regulator_action(void *_data)
714 {
715 	struct isl29018_chip *chip = _data;
716 	int err;
717 
718 	err = regulator_disable(chip->vcc_reg);
719 	if (err)
720 		pr_err("failed to disable isl29018's VCC regulator!\n");
721 }
722 
723 static int isl29018_probe(struct i2c_client *client,
724 			  const struct i2c_device_id *id)
725 {
726 	struct isl29018_chip *chip;
727 	struct iio_dev *indio_dev;
728 	int err;
729 	const char *name = NULL;
730 	int dev_id = 0;
731 
732 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
733 	if (!indio_dev)
734 		return -ENOMEM;
735 
736 	chip = iio_priv(indio_dev);
737 
738 	i2c_set_clientdata(client, indio_dev);
739 
740 	if (id) {
741 		name = id->name;
742 		dev_id = id->driver_data;
743 	}
744 
745 	if (ACPI_HANDLE(&client->dev))
746 		name = isl29018_match_acpi_device(&client->dev, &dev_id);
747 
748 	mutex_init(&chip->lock);
749 
750 	chip->type = dev_id;
751 	chip->calibscale = 1;
752 	chip->ucalibscale = 0;
753 	chip->int_time = ISL29018_INT_TIME_16;
754 	chip->scale = isl29018_scales[chip->int_time][0];
755 	chip->suspended = false;
756 
757 	chip->vcc_reg = devm_regulator_get(&client->dev, "vcc");
758 	if (IS_ERR(chip->vcc_reg)) {
759 		err = PTR_ERR(chip->vcc_reg);
760 		if (err != -EPROBE_DEFER)
761 			dev_err(&client->dev, "failed to get VCC regulator!\n");
762 		return err;
763 	}
764 
765 	err = regulator_enable(chip->vcc_reg);
766 	if (err) {
767 		dev_err(&client->dev, "failed to enable VCC regulator!\n");
768 		return err;
769 	}
770 
771 	err = devm_add_action_or_reset(&client->dev, isl29018_disable_regulator_action,
772 				 chip);
773 	if (err) {
774 		dev_err(&client->dev, "failed to setup regulator cleanup action!\n");
775 		return err;
776 	}
777 
778 	chip->regmap = devm_regmap_init_i2c(client,
779 				isl29018_chip_info_tbl[dev_id].regmap_cfg);
780 	if (IS_ERR(chip->regmap)) {
781 		err = PTR_ERR(chip->regmap);
782 		dev_err(&client->dev, "regmap initialization fails: %d\n", err);
783 		return err;
784 	}
785 
786 	err = isl29018_chip_init(chip);
787 	if (err)
788 		return err;
789 
790 	indio_dev->info = isl29018_chip_info_tbl[dev_id].indio_info;
791 	indio_dev->channels = isl29018_chip_info_tbl[dev_id].channels;
792 	indio_dev->num_channels = isl29018_chip_info_tbl[dev_id].num_channels;
793 	indio_dev->name = name;
794 	indio_dev->dev.parent = &client->dev;
795 	indio_dev->modes = INDIO_DIRECT_MODE;
796 
797 	return devm_iio_device_register(&client->dev, indio_dev);
798 }
799 
800 #ifdef CONFIG_PM_SLEEP
801 static int isl29018_suspend(struct device *dev)
802 {
803 	struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
804 	int ret;
805 
806 	mutex_lock(&chip->lock);
807 
808 	/*
809 	 * Since this driver uses only polling commands, we are by default in
810 	 * auto shutdown (ie, power-down) mode.
811 	 * So we do not have much to do here.
812 	 */
813 	chip->suspended = true;
814 	ret = regulator_disable(chip->vcc_reg);
815 	if (ret)
816 		dev_err(dev, "failed to disable VCC regulator\n");
817 
818 	mutex_unlock(&chip->lock);
819 
820 	return ret;
821 }
822 
823 static int isl29018_resume(struct device *dev)
824 {
825 	struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
826 	int err;
827 
828 	mutex_lock(&chip->lock);
829 
830 	err = regulator_enable(chip->vcc_reg);
831 	if (err) {
832 		dev_err(dev, "failed to enable VCC regulator\n");
833 		mutex_unlock(&chip->lock);
834 		return err;
835 	}
836 
837 	err = isl29018_chip_init(chip);
838 	if (!err)
839 		chip->suspended = false;
840 
841 	mutex_unlock(&chip->lock);
842 
843 	return err;
844 }
845 
846 static SIMPLE_DEV_PM_OPS(isl29018_pm_ops, isl29018_suspend, isl29018_resume);
847 #define ISL29018_PM_OPS (&isl29018_pm_ops)
848 #else
849 #define ISL29018_PM_OPS NULL
850 #endif
851 
852 #ifdef CONFIG_ACPI
853 static const struct acpi_device_id isl29018_acpi_match[] = {
854 	{"ISL29018", isl29018},
855 	{"ISL29023", isl29023},
856 	{"ISL29035", isl29035},
857 	{},
858 };
859 MODULE_DEVICE_TABLE(acpi, isl29018_acpi_match);
860 #endif
861 
862 static const struct i2c_device_id isl29018_id[] = {
863 	{"isl29018", isl29018},
864 	{"isl29023", isl29023},
865 	{"isl29035", isl29035},
866 	{}
867 };
868 MODULE_DEVICE_TABLE(i2c, isl29018_id);
869 
870 static const struct of_device_id isl29018_of_match[] = {
871 	{ .compatible = "isil,isl29018", },
872 	{ .compatible = "isil,isl29023", },
873 	{ .compatible = "isil,isl29035", },
874 	{ },
875 };
876 MODULE_DEVICE_TABLE(of, isl29018_of_match);
877 
878 static struct i2c_driver isl29018_driver = {
879 	.driver	 = {
880 			.name = "isl29018",
881 			.acpi_match_table = ACPI_PTR(isl29018_acpi_match),
882 			.pm = ISL29018_PM_OPS,
883 			.of_match_table = isl29018_of_match,
884 		    },
885 	.probe	 = isl29018_probe,
886 	.id_table = isl29018_id,
887 };
888 module_i2c_driver(isl29018_driver);
889 
890 MODULE_DESCRIPTION("ISL29018 Ambient Light Sensor driver");
891 MODULE_LICENSE("GPL");
892