xref: /openbmc/linux/drivers/iio/light/isl29018.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * A iio driver for the light sensor ISL 29018/29023/29035.
4  *
5  * IIO driver for monitoring ambient light intensity in luxi, proximity
6  * sensing and infrared sensing.
7  *
8  * Copyright (c) 2010, NVIDIA Corporation.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/i2c.h>
13 #include <linux/err.h>
14 #include <linux/mutex.h>
15 #include <linux/delay.h>
16 #include <linux/regmap.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/slab.h>
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/acpi.h>
22 
23 #define ISL29018_CONV_TIME_MS		100
24 
25 #define ISL29018_REG_ADD_COMMAND1	0x00
26 #define ISL29018_CMD1_OPMODE_SHIFT	5
27 #define ISL29018_CMD1_OPMODE_MASK	(7 << ISL29018_CMD1_OPMODE_SHIFT)
28 #define ISL29018_CMD1_OPMODE_POWER_DOWN	0
29 #define ISL29018_CMD1_OPMODE_ALS_ONCE	1
30 #define ISL29018_CMD1_OPMODE_IR_ONCE	2
31 #define ISL29018_CMD1_OPMODE_PROX_ONCE	3
32 
33 #define ISL29018_REG_ADD_COMMAND2	0x01
34 #define ISL29018_CMD2_RESOLUTION_SHIFT	2
35 #define ISL29018_CMD2_RESOLUTION_MASK	(0x3 << ISL29018_CMD2_RESOLUTION_SHIFT)
36 
37 #define ISL29018_CMD2_RANGE_SHIFT	0
38 #define ISL29018_CMD2_RANGE_MASK	(0x3 << ISL29018_CMD2_RANGE_SHIFT)
39 
40 #define ISL29018_CMD2_SCHEME_SHIFT	7
41 #define ISL29018_CMD2_SCHEME_MASK	(0x1 << ISL29018_CMD2_SCHEME_SHIFT)
42 
43 #define ISL29018_REG_ADD_DATA_LSB	0x02
44 #define ISL29018_REG_ADD_DATA_MSB	0x03
45 
46 #define ISL29018_REG_TEST		0x08
47 #define ISL29018_TEST_SHIFT		0
48 #define ISL29018_TEST_MASK		(0xFF << ISL29018_TEST_SHIFT)
49 
50 #define ISL29035_REG_DEVICE_ID		0x0F
51 #define ISL29035_DEVICE_ID_SHIFT	0x03
52 #define ISL29035_DEVICE_ID_MASK		(0x7 << ISL29035_DEVICE_ID_SHIFT)
53 #define ISL29035_DEVICE_ID		0x5
54 #define ISL29035_BOUT_SHIFT		0x07
55 #define ISL29035_BOUT_MASK		(0x01 << ISL29035_BOUT_SHIFT)
56 
57 enum isl29018_int_time {
58 	ISL29018_INT_TIME_16,
59 	ISL29018_INT_TIME_12,
60 	ISL29018_INT_TIME_8,
61 	ISL29018_INT_TIME_4,
62 };
63 
64 static const unsigned int isl29018_int_utimes[3][4] = {
65 	{90000, 5630, 351, 21},
66 	{90000, 5600, 352, 22},
67 	{105000, 6500, 410, 25},
68 };
69 
70 static const struct isl29018_scale {
71 	unsigned int scale;
72 	unsigned int uscale;
73 } isl29018_scales[4][4] = {
74 	{ {0, 15258}, {0, 61035}, {0, 244140}, {0, 976562} },
75 	{ {0, 244140}, {0, 976562}, {3, 906250}, {15, 625000} },
76 	{ {3, 906250}, {15, 625000}, {62, 500000}, {250, 0} },
77 	{ {62, 500000}, {250, 0}, {1000, 0}, {4000, 0} }
78 };
79 
80 struct isl29018_chip {
81 	struct regmap		*regmap;
82 	struct mutex		lock;
83 	int			type;
84 	unsigned int		calibscale;
85 	unsigned int		ucalibscale;
86 	unsigned int		int_time;
87 	struct isl29018_scale	scale;
88 	int			prox_scheme;
89 	bool			suspended;
90 	struct regulator	*vcc_reg;
91 };
92 
93 static int isl29018_set_integration_time(struct isl29018_chip *chip,
94 					 unsigned int utime)
95 {
96 	unsigned int i;
97 	int ret;
98 	unsigned int int_time, new_int_time;
99 
100 	for (i = 0; i < ARRAY_SIZE(isl29018_int_utimes[chip->type]); ++i) {
101 		if (utime == isl29018_int_utimes[chip->type][i]) {
102 			new_int_time = i;
103 			break;
104 		}
105 	}
106 
107 	if (i >= ARRAY_SIZE(isl29018_int_utimes[chip->type]))
108 		return -EINVAL;
109 
110 	ret = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
111 				 ISL29018_CMD2_RESOLUTION_MASK,
112 				 i << ISL29018_CMD2_RESOLUTION_SHIFT);
113 	if (ret < 0)
114 		return ret;
115 
116 	/* Keep the same range when integration time changes */
117 	int_time = chip->int_time;
118 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[int_time]); ++i) {
119 		if (chip->scale.scale == isl29018_scales[int_time][i].scale &&
120 		    chip->scale.uscale == isl29018_scales[int_time][i].uscale) {
121 			chip->scale = isl29018_scales[new_int_time][i];
122 			break;
123 		}
124 	}
125 	chip->int_time = new_int_time;
126 
127 	return 0;
128 }
129 
130 static int isl29018_set_scale(struct isl29018_chip *chip, int scale, int uscale)
131 {
132 	unsigned int i;
133 	int ret;
134 	struct isl29018_scale new_scale;
135 
136 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[chip->int_time]); ++i) {
137 		if (scale == isl29018_scales[chip->int_time][i].scale &&
138 		    uscale == isl29018_scales[chip->int_time][i].uscale) {
139 			new_scale = isl29018_scales[chip->int_time][i];
140 			break;
141 		}
142 	}
143 
144 	if (i >= ARRAY_SIZE(isl29018_scales[chip->int_time]))
145 		return -EINVAL;
146 
147 	ret = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
148 				 ISL29018_CMD2_RANGE_MASK,
149 				 i << ISL29018_CMD2_RANGE_SHIFT);
150 	if (ret < 0)
151 		return ret;
152 
153 	chip->scale = new_scale;
154 
155 	return 0;
156 }
157 
158 static int isl29018_read_sensor_input(struct isl29018_chip *chip, int mode)
159 {
160 	int status;
161 	unsigned int lsb;
162 	unsigned int msb;
163 	struct device *dev = regmap_get_device(chip->regmap);
164 
165 	/* Set mode */
166 	status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1,
167 			      mode << ISL29018_CMD1_OPMODE_SHIFT);
168 	if (status) {
169 		dev_err(dev,
170 			"Error in setting operating mode err %d\n", status);
171 		return status;
172 	}
173 	msleep(ISL29018_CONV_TIME_MS);
174 	status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_LSB, &lsb);
175 	if (status < 0) {
176 		dev_err(dev,
177 			"Error in reading LSB DATA with err %d\n", status);
178 		return status;
179 	}
180 
181 	status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_MSB, &msb);
182 	if (status < 0) {
183 		dev_err(dev,
184 			"Error in reading MSB DATA with error %d\n", status);
185 		return status;
186 	}
187 	dev_vdbg(dev, "MSB 0x%x and LSB 0x%x\n", msb, lsb);
188 
189 	return (msb << 8) | lsb;
190 }
191 
192 static int isl29018_read_lux(struct isl29018_chip *chip, int *lux)
193 {
194 	int lux_data;
195 	unsigned int data_x_range;
196 
197 	lux_data = isl29018_read_sensor_input(chip,
198 					      ISL29018_CMD1_OPMODE_ALS_ONCE);
199 	if (lux_data < 0)
200 		return lux_data;
201 
202 	data_x_range = lux_data * chip->scale.scale +
203 		       lux_data * chip->scale.uscale / 1000000;
204 	*lux = data_x_range * chip->calibscale +
205 	       data_x_range * chip->ucalibscale / 1000000;
206 
207 	return 0;
208 }
209 
210 static int isl29018_read_ir(struct isl29018_chip *chip, int *ir)
211 {
212 	int ir_data;
213 
214 	ir_data = isl29018_read_sensor_input(chip,
215 					     ISL29018_CMD1_OPMODE_IR_ONCE);
216 	if (ir_data < 0)
217 		return ir_data;
218 
219 	*ir = ir_data;
220 
221 	return 0;
222 }
223 
224 static int isl29018_read_proximity_ir(struct isl29018_chip *chip, int scheme,
225 				      int *near_ir)
226 {
227 	int status;
228 	int prox_data = -1;
229 	int ir_data = -1;
230 	struct device *dev = regmap_get_device(chip->regmap);
231 
232 	/* Do proximity sensing with required scheme */
233 	status = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMAND2,
234 				    ISL29018_CMD2_SCHEME_MASK,
235 				    scheme << ISL29018_CMD2_SCHEME_SHIFT);
236 	if (status) {
237 		dev_err(dev, "Error in setting operating mode\n");
238 		return status;
239 	}
240 
241 	prox_data = isl29018_read_sensor_input(chip,
242 					       ISL29018_CMD1_OPMODE_PROX_ONCE);
243 	if (prox_data < 0)
244 		return prox_data;
245 
246 	if (scheme == 1) {
247 		*near_ir = prox_data;
248 		return 0;
249 	}
250 
251 	ir_data = isl29018_read_sensor_input(chip,
252 					     ISL29018_CMD1_OPMODE_IR_ONCE);
253 	if (ir_data < 0)
254 		return ir_data;
255 
256 	if (prox_data >= ir_data)
257 		*near_ir = prox_data - ir_data;
258 	else
259 		*near_ir = 0;
260 
261 	return 0;
262 }
263 
264 static ssize_t in_illuminance_scale_available_show
265 			(struct device *dev, struct device_attribute *attr,
266 			 char *buf)
267 {
268 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
269 	struct isl29018_chip *chip = iio_priv(indio_dev);
270 	unsigned int i;
271 	int len = 0;
272 
273 	mutex_lock(&chip->lock);
274 	for (i = 0; i < ARRAY_SIZE(isl29018_scales[chip->int_time]); ++i)
275 		len += sprintf(buf + len, "%d.%06d ",
276 			       isl29018_scales[chip->int_time][i].scale,
277 			       isl29018_scales[chip->int_time][i].uscale);
278 	mutex_unlock(&chip->lock);
279 
280 	buf[len - 1] = '\n';
281 
282 	return len;
283 }
284 
285 static ssize_t in_illuminance_integration_time_available_show
286 			(struct device *dev, struct device_attribute *attr,
287 			 char *buf)
288 {
289 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
290 	struct isl29018_chip *chip = iio_priv(indio_dev);
291 	unsigned int i;
292 	int len = 0;
293 
294 	for (i = 0; i < ARRAY_SIZE(isl29018_int_utimes[chip->type]); ++i)
295 		len += sprintf(buf + len, "0.%06d ",
296 			       isl29018_int_utimes[chip->type][i]);
297 
298 	buf[len - 1] = '\n';
299 
300 	return len;
301 }
302 
303 /*
304  * From ISL29018 Data Sheet (FN6619.4, Oct 8, 2012) regarding the
305  * infrared suppression:
306  *
307  *   Proximity Sensing Scheme: Bit 7. This bit programs the function
308  * of the proximity detection. Logic 0 of this bit, Scheme 0, makes
309  * full n (4, 8, 12, 16) bits (unsigned) proximity detection. The range
310  * of Scheme 0 proximity count is from 0 to 2^n. Logic 1 of this bit,
311  * Scheme 1, makes n-1 (3, 7, 11, 15) bits (2's complementary)
312  * proximity_less_ambient detection. The range of Scheme 1
313  * proximity count is from -2^(n-1) to 2^(n-1) . The sign bit is extended
314  * for resolutions less than 16. While Scheme 0 has wider dynamic
315  * range, Scheme 1 proximity detection is less affected by the
316  * ambient IR noise variation.
317  *
318  * 0 Sensing IR from LED and ambient
319  * 1 Sensing IR from LED with ambient IR rejection
320  */
321 static ssize_t proximity_on_chip_ambient_infrared_suppression_show
322 			(struct device *dev, struct device_attribute *attr,
323 			 char *buf)
324 {
325 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
326 	struct isl29018_chip *chip = iio_priv(indio_dev);
327 
328 	/*
329 	 * Return the "proximity scheme" i.e. if the chip does on chip
330 	 * infrared suppression (1 means perform on chip suppression)
331 	 */
332 	return sprintf(buf, "%d\n", chip->prox_scheme);
333 }
334 
335 static ssize_t proximity_on_chip_ambient_infrared_suppression_store
336 			(struct device *dev, struct device_attribute *attr,
337 			 const char *buf, size_t count)
338 {
339 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
340 	struct isl29018_chip *chip = iio_priv(indio_dev);
341 	int val;
342 
343 	if (kstrtoint(buf, 10, &val))
344 		return -EINVAL;
345 	if (!(val == 0 || val == 1))
346 		return -EINVAL;
347 
348 	/*
349 	 * Get the "proximity scheme" i.e. if the chip does on chip
350 	 * infrared suppression (1 means perform on chip suppression)
351 	 */
352 	mutex_lock(&chip->lock);
353 	chip->prox_scheme = val;
354 	mutex_unlock(&chip->lock);
355 
356 	return count;
357 }
358 
359 static int isl29018_write_raw(struct iio_dev *indio_dev,
360 			      struct iio_chan_spec const *chan,
361 			      int val,
362 			      int val2,
363 			      long mask)
364 {
365 	struct isl29018_chip *chip = iio_priv(indio_dev);
366 	int ret = -EINVAL;
367 
368 	mutex_lock(&chip->lock);
369 	if (chip->suspended) {
370 		ret = -EBUSY;
371 		goto write_done;
372 	}
373 	switch (mask) {
374 	case IIO_CHAN_INFO_CALIBSCALE:
375 		if (chan->type == IIO_LIGHT) {
376 			chip->calibscale = val;
377 			chip->ucalibscale = val2;
378 			ret = 0;
379 		}
380 		break;
381 	case IIO_CHAN_INFO_INT_TIME:
382 		if (chan->type == IIO_LIGHT && !val)
383 			ret = isl29018_set_integration_time(chip, val2);
384 		break;
385 	case IIO_CHAN_INFO_SCALE:
386 		if (chan->type == IIO_LIGHT)
387 			ret = isl29018_set_scale(chip, val, val2);
388 		break;
389 	default:
390 		break;
391 	}
392 
393 write_done:
394 	mutex_unlock(&chip->lock);
395 
396 	return ret;
397 }
398 
399 static int isl29018_read_raw(struct iio_dev *indio_dev,
400 			     struct iio_chan_spec const *chan,
401 			     int *val,
402 			     int *val2,
403 			     long mask)
404 {
405 	int ret = -EINVAL;
406 	struct isl29018_chip *chip = iio_priv(indio_dev);
407 
408 	mutex_lock(&chip->lock);
409 	if (chip->suspended) {
410 		ret = -EBUSY;
411 		goto read_done;
412 	}
413 	switch (mask) {
414 	case IIO_CHAN_INFO_RAW:
415 	case IIO_CHAN_INFO_PROCESSED:
416 		switch (chan->type) {
417 		case IIO_LIGHT:
418 			ret = isl29018_read_lux(chip, val);
419 			break;
420 		case IIO_INTENSITY:
421 			ret = isl29018_read_ir(chip, val);
422 			break;
423 		case IIO_PROXIMITY:
424 			ret = isl29018_read_proximity_ir(chip,
425 							 chip->prox_scheme,
426 							 val);
427 			break;
428 		default:
429 			break;
430 		}
431 		if (!ret)
432 			ret = IIO_VAL_INT;
433 		break;
434 	case IIO_CHAN_INFO_INT_TIME:
435 		if (chan->type == IIO_LIGHT) {
436 			*val = 0;
437 			*val2 = isl29018_int_utimes[chip->type][chip->int_time];
438 			ret = IIO_VAL_INT_PLUS_MICRO;
439 		}
440 		break;
441 	case IIO_CHAN_INFO_SCALE:
442 		if (chan->type == IIO_LIGHT) {
443 			*val = chip->scale.scale;
444 			*val2 = chip->scale.uscale;
445 			ret = IIO_VAL_INT_PLUS_MICRO;
446 		}
447 		break;
448 	case IIO_CHAN_INFO_CALIBSCALE:
449 		if (chan->type == IIO_LIGHT) {
450 			*val = chip->calibscale;
451 			*val2 = chip->ucalibscale;
452 			ret = IIO_VAL_INT_PLUS_MICRO;
453 		}
454 		break;
455 	default:
456 		break;
457 	}
458 
459 read_done:
460 	mutex_unlock(&chip->lock);
461 
462 	return ret;
463 }
464 
465 #define ISL29018_LIGHT_CHANNEL {					\
466 	.type = IIO_LIGHT,						\
467 	.indexed = 1,							\
468 	.channel = 0,							\
469 	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |		\
470 	BIT(IIO_CHAN_INFO_CALIBSCALE) |					\
471 	BIT(IIO_CHAN_INFO_SCALE) |					\
472 	BIT(IIO_CHAN_INFO_INT_TIME),					\
473 }
474 
475 #define ISL29018_IR_CHANNEL {						\
476 	.type = IIO_INTENSITY,						\
477 	.modified = 1,							\
478 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
479 	.channel2 = IIO_MOD_LIGHT_IR,					\
480 }
481 
482 #define ISL29018_PROXIMITY_CHANNEL {					\
483 	.type = IIO_PROXIMITY,						\
484 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
485 }
486 
487 static const struct iio_chan_spec isl29018_channels[] = {
488 	ISL29018_LIGHT_CHANNEL,
489 	ISL29018_IR_CHANNEL,
490 	ISL29018_PROXIMITY_CHANNEL,
491 };
492 
493 static const struct iio_chan_spec isl29023_channels[] = {
494 	ISL29018_LIGHT_CHANNEL,
495 	ISL29018_IR_CHANNEL,
496 };
497 
498 static IIO_DEVICE_ATTR_RO(in_illuminance_integration_time_available, 0);
499 static IIO_DEVICE_ATTR_RO(in_illuminance_scale_available, 0);
500 static IIO_DEVICE_ATTR_RW(proximity_on_chip_ambient_infrared_suppression, 0);
501 
502 #define ISL29018_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
503 
504 static struct attribute *isl29018_attributes[] = {
505 	ISL29018_DEV_ATTR(in_illuminance_scale_available),
506 	ISL29018_DEV_ATTR(in_illuminance_integration_time_available),
507 	ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_suppression),
508 	NULL
509 };
510 
511 static struct attribute *isl29023_attributes[] = {
512 	ISL29018_DEV_ATTR(in_illuminance_scale_available),
513 	ISL29018_DEV_ATTR(in_illuminance_integration_time_available),
514 	NULL
515 };
516 
517 static const struct attribute_group isl29018_group = {
518 	.attrs = isl29018_attributes,
519 };
520 
521 static const struct attribute_group isl29023_group = {
522 	.attrs = isl29023_attributes,
523 };
524 
525 enum {
526 	isl29018,
527 	isl29023,
528 	isl29035,
529 };
530 
531 static int isl29018_chip_init(struct isl29018_chip *chip)
532 {
533 	int status;
534 	struct device *dev = regmap_get_device(chip->regmap);
535 
536 	if (chip->type == isl29035) {
537 		unsigned int id;
538 
539 		status = regmap_read(chip->regmap, ISL29035_REG_DEVICE_ID, &id);
540 		if (status < 0) {
541 			dev_err(dev,
542 				"Error reading ID register with error %d\n",
543 				status);
544 			return status;
545 		}
546 
547 		id = (id & ISL29035_DEVICE_ID_MASK) >> ISL29035_DEVICE_ID_SHIFT;
548 
549 		if (id != ISL29035_DEVICE_ID)
550 			return -ENODEV;
551 
552 		/* Clear brownout bit */
553 		status = regmap_update_bits(chip->regmap,
554 					    ISL29035_REG_DEVICE_ID,
555 					    ISL29035_BOUT_MASK, 0);
556 		if (status < 0)
557 			return status;
558 	}
559 
560 	/*
561 	 * Code added per Intersil Application Note 1534:
562 	 *     When VDD sinks to approximately 1.8V or below, some of
563 	 * the part's registers may change their state. When VDD
564 	 * recovers to 2.25V (or greater), the part may thus be in an
565 	 * unknown mode of operation. The user can return the part to
566 	 * a known mode of operation either by (a) setting VDD = 0V for
567 	 * 1 second or more and then powering back up with a slew rate
568 	 * of 0.5V/ms or greater, or (b) via I2C disable all ALS/PROX
569 	 * conversions, clear the test registers, and then rewrite all
570 	 * registers to the desired values.
571 	 * ...
572 	 * For ISL29011, ISL29018, ISL29021, ISL29023
573 	 * 1. Write 0x00 to register 0x08 (TEST)
574 	 * 2. Write 0x00 to register 0x00 (CMD1)
575 	 * 3. Rewrite all registers to the desired values
576 	 *
577 	 * ISL29018 Data Sheet (FN6619.1, Feb 11, 2010) essentially says
578 	 * the same thing EXCEPT the data sheet asks for a 1ms delay after
579 	 * writing the CMD1 register.
580 	 */
581 	status = regmap_write(chip->regmap, ISL29018_REG_TEST, 0x0);
582 	if (status < 0) {
583 		dev_err(dev, "Failed to clear isl29018 TEST reg.(%d)\n",
584 			status);
585 		return status;
586 	}
587 
588 	/*
589 	 * See Intersil AN1534 comments above.
590 	 * "Operating Mode" (COMMAND1) register is reprogrammed when
591 	 * data is read from the device.
592 	 */
593 	status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1, 0);
594 	if (status < 0) {
595 		dev_err(dev, "Failed to clear isl29018 CMD1 reg.(%d)\n",
596 			status);
597 		return status;
598 	}
599 
600 	usleep_range(1000, 2000);	/* per data sheet, page 10 */
601 
602 	/* Set defaults */
603 	status = isl29018_set_scale(chip, chip->scale.scale,
604 				    chip->scale.uscale);
605 	if (status < 0) {
606 		dev_err(dev, "Init of isl29018 fails\n");
607 		return status;
608 	}
609 
610 	status = isl29018_set_integration_time(chip,
611 			isl29018_int_utimes[chip->type][chip->int_time]);
612 	if (status < 0)
613 		dev_err(dev, "Init of isl29018 fails\n");
614 
615 	return status;
616 }
617 
618 static const struct iio_info isl29018_info = {
619 	.attrs = &isl29018_group,
620 	.read_raw = isl29018_read_raw,
621 	.write_raw = isl29018_write_raw,
622 };
623 
624 static const struct iio_info isl29023_info = {
625 	.attrs = &isl29023_group,
626 	.read_raw = isl29018_read_raw,
627 	.write_raw = isl29018_write_raw,
628 };
629 
630 static bool isl29018_is_volatile_reg(struct device *dev, unsigned int reg)
631 {
632 	switch (reg) {
633 	case ISL29018_REG_ADD_DATA_LSB:
634 	case ISL29018_REG_ADD_DATA_MSB:
635 	case ISL29018_REG_ADD_COMMAND1:
636 	case ISL29018_REG_TEST:
637 	case ISL29035_REG_DEVICE_ID:
638 		return true;
639 	default:
640 		return false;
641 	}
642 }
643 
644 static const struct regmap_config isl29018_regmap_config = {
645 	.reg_bits = 8,
646 	.val_bits = 8,
647 	.volatile_reg = isl29018_is_volatile_reg,
648 	.max_register = ISL29018_REG_TEST,
649 	.num_reg_defaults_raw = ISL29018_REG_TEST + 1,
650 	.cache_type = REGCACHE_RBTREE,
651 };
652 
653 static const struct regmap_config isl29035_regmap_config = {
654 	.reg_bits = 8,
655 	.val_bits = 8,
656 	.volatile_reg = isl29018_is_volatile_reg,
657 	.max_register = ISL29035_REG_DEVICE_ID,
658 	.num_reg_defaults_raw = ISL29035_REG_DEVICE_ID + 1,
659 	.cache_type = REGCACHE_RBTREE,
660 };
661 
662 struct isl29018_chip_info {
663 	const struct iio_chan_spec *channels;
664 	int num_channels;
665 	const struct iio_info *indio_info;
666 	const struct regmap_config *regmap_cfg;
667 };
668 
669 static const struct isl29018_chip_info isl29018_chip_info_tbl[] = {
670 	[isl29018] = {
671 		.channels = isl29018_channels,
672 		.num_channels = ARRAY_SIZE(isl29018_channels),
673 		.indio_info = &isl29018_info,
674 		.regmap_cfg = &isl29018_regmap_config,
675 	},
676 	[isl29023] = {
677 		.channels = isl29023_channels,
678 		.num_channels = ARRAY_SIZE(isl29023_channels),
679 		.indio_info = &isl29023_info,
680 		.regmap_cfg = &isl29018_regmap_config,
681 	},
682 	[isl29035] = {
683 		.channels = isl29023_channels,
684 		.num_channels = ARRAY_SIZE(isl29023_channels),
685 		.indio_info = &isl29023_info,
686 		.regmap_cfg = &isl29035_regmap_config,
687 	},
688 };
689 
690 static const char *isl29018_match_acpi_device(struct device *dev, int *data)
691 {
692 	const struct acpi_device_id *id;
693 
694 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
695 
696 	if (!id)
697 		return NULL;
698 
699 	*data = (int)id->driver_data;
700 
701 	return dev_name(dev);
702 }
703 
704 static void isl29018_disable_regulator_action(void *_data)
705 {
706 	struct isl29018_chip *chip = _data;
707 	int err;
708 
709 	err = regulator_disable(chip->vcc_reg);
710 	if (err)
711 		pr_err("failed to disable isl29018's VCC regulator!\n");
712 }
713 
714 static int isl29018_probe(struct i2c_client *client,
715 			  const struct i2c_device_id *id)
716 {
717 	struct isl29018_chip *chip;
718 	struct iio_dev *indio_dev;
719 	int err;
720 	const char *name = NULL;
721 	int dev_id = 0;
722 
723 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
724 	if (!indio_dev)
725 		return -ENOMEM;
726 
727 	chip = iio_priv(indio_dev);
728 
729 	i2c_set_clientdata(client, indio_dev);
730 
731 	if (id) {
732 		name = id->name;
733 		dev_id = id->driver_data;
734 	}
735 
736 	if (ACPI_HANDLE(&client->dev))
737 		name = isl29018_match_acpi_device(&client->dev, &dev_id);
738 
739 	mutex_init(&chip->lock);
740 
741 	chip->type = dev_id;
742 	chip->calibscale = 1;
743 	chip->ucalibscale = 0;
744 	chip->int_time = ISL29018_INT_TIME_16;
745 	chip->scale = isl29018_scales[chip->int_time][0];
746 	chip->suspended = false;
747 
748 	chip->vcc_reg = devm_regulator_get(&client->dev, "vcc");
749 	if (IS_ERR(chip->vcc_reg))
750 		return dev_err_probe(&client->dev, PTR_ERR(chip->vcc_reg),
751 				     "failed to get VCC regulator!\n");
752 
753 	err = regulator_enable(chip->vcc_reg);
754 	if (err) {
755 		dev_err(&client->dev, "failed to enable VCC regulator!\n");
756 		return err;
757 	}
758 
759 	err = devm_add_action_or_reset(&client->dev, isl29018_disable_regulator_action,
760 				 chip);
761 	if (err) {
762 		dev_err(&client->dev, "failed to setup regulator cleanup action!\n");
763 		return err;
764 	}
765 
766 	chip->regmap = devm_regmap_init_i2c(client,
767 				isl29018_chip_info_tbl[dev_id].regmap_cfg);
768 	if (IS_ERR(chip->regmap)) {
769 		err = PTR_ERR(chip->regmap);
770 		dev_err(&client->dev, "regmap initialization fails: %d\n", err);
771 		return err;
772 	}
773 
774 	err = isl29018_chip_init(chip);
775 	if (err)
776 		return err;
777 
778 	indio_dev->info = isl29018_chip_info_tbl[dev_id].indio_info;
779 	indio_dev->channels = isl29018_chip_info_tbl[dev_id].channels;
780 	indio_dev->num_channels = isl29018_chip_info_tbl[dev_id].num_channels;
781 	indio_dev->name = name;
782 	indio_dev->modes = INDIO_DIRECT_MODE;
783 
784 	return devm_iio_device_register(&client->dev, indio_dev);
785 }
786 
787 #ifdef CONFIG_PM_SLEEP
788 static int isl29018_suspend(struct device *dev)
789 {
790 	struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
791 	int ret;
792 
793 	mutex_lock(&chip->lock);
794 
795 	/*
796 	 * Since this driver uses only polling commands, we are by default in
797 	 * auto shutdown (ie, power-down) mode.
798 	 * So we do not have much to do here.
799 	 */
800 	chip->suspended = true;
801 	ret = regulator_disable(chip->vcc_reg);
802 	if (ret)
803 		dev_err(dev, "failed to disable VCC regulator\n");
804 
805 	mutex_unlock(&chip->lock);
806 
807 	return ret;
808 }
809 
810 static int isl29018_resume(struct device *dev)
811 {
812 	struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
813 	int err;
814 
815 	mutex_lock(&chip->lock);
816 
817 	err = regulator_enable(chip->vcc_reg);
818 	if (err) {
819 		dev_err(dev, "failed to enable VCC regulator\n");
820 		mutex_unlock(&chip->lock);
821 		return err;
822 	}
823 
824 	err = isl29018_chip_init(chip);
825 	if (!err)
826 		chip->suspended = false;
827 
828 	mutex_unlock(&chip->lock);
829 
830 	return err;
831 }
832 
833 static SIMPLE_DEV_PM_OPS(isl29018_pm_ops, isl29018_suspend, isl29018_resume);
834 #define ISL29018_PM_OPS (&isl29018_pm_ops)
835 #else
836 #define ISL29018_PM_OPS NULL
837 #endif
838 
839 #ifdef CONFIG_ACPI
840 static const struct acpi_device_id isl29018_acpi_match[] = {
841 	{"ISL29018", isl29018},
842 	{"ISL29023", isl29023},
843 	{"ISL29035", isl29035},
844 	{},
845 };
846 MODULE_DEVICE_TABLE(acpi, isl29018_acpi_match);
847 #endif
848 
849 static const struct i2c_device_id isl29018_id[] = {
850 	{"isl29018", isl29018},
851 	{"isl29023", isl29023},
852 	{"isl29035", isl29035},
853 	{}
854 };
855 MODULE_DEVICE_TABLE(i2c, isl29018_id);
856 
857 static const struct of_device_id isl29018_of_match[] = {
858 	{ .compatible = "isil,isl29018", },
859 	{ .compatible = "isil,isl29023", },
860 	{ .compatible = "isil,isl29035", },
861 	{ },
862 };
863 MODULE_DEVICE_TABLE(of, isl29018_of_match);
864 
865 static struct i2c_driver isl29018_driver = {
866 	.driver	 = {
867 			.name = "isl29018",
868 			.acpi_match_table = ACPI_PTR(isl29018_acpi_match),
869 			.pm = ISL29018_PM_OPS,
870 			.of_match_table = isl29018_of_match,
871 		    },
872 	.probe	 = isl29018_probe,
873 	.id_table = isl29018_id,
874 };
875 module_i2c_driver(isl29018_driver);
876 
877 MODULE_DESCRIPTION("ISL29018 Ambient Light Sensor driver");
878 MODULE_LICENSE("GPL");
879