xref: /linux/drivers/iio/light/vcnl4035.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * VCNL4035 Ambient Light and Proximity Sensor - 7-bit I2C slave address 0x60
4  *
5  * Copyright (c) 2018, DENX Software Engineering GmbH
6  * Author: Parthiban Nallathambi <pn@denx.de>
7  *
8  * TODO: Proximity
9  */
10 #include <linux/bitops.h>
11 #include <linux/bitfield.h>
12 #include <linux/i2c.h>
13 #include <linux/module.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/regmap.h>
16 
17 #include <linux/iio/buffer.h>
18 #include <linux/iio/events.h>
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/trigger.h>
22 #include <linux/iio/trigger_consumer.h>
23 #include <linux/iio/triggered_buffer.h>
24 
25 #define VCNL4035_DRV_NAME	"vcnl4035"
26 #define VCNL4035_IRQ_NAME	"vcnl4035_event"
27 #define VCNL4035_REGMAP_NAME	"vcnl4035_regmap"
28 
29 /* Device registers */
30 #define VCNL4035_ALS_CONF	0x00
31 #define VCNL4035_ALS_THDH	0x01
32 #define VCNL4035_ALS_THDL	0x02
33 #define VCNL4035_ALS_DATA	0x0B
34 #define VCNL4035_WHITE_DATA	0x0C
35 #define VCNL4035_INT_FLAG	0x0D
36 #define VCNL4035_DEV_ID		0x0E
37 
38 /* Register masks */
39 #define VCNL4035_MODE_ALS_MASK		BIT(0)
40 #define VCNL4035_MODE_ALS_WHITE_CHAN	BIT(8)
41 #define VCNL4035_MODE_ALS_INT_MASK	BIT(1)
42 #define VCNL4035_ALS_IT_MASK		GENMASK(7, 5)
43 #define VCNL4035_ALS_PERS_MASK		GENMASK(3, 2)
44 #define VCNL4035_INT_ALS_IF_H_MASK	BIT(12)
45 #define VCNL4035_INT_ALS_IF_L_MASK	BIT(13)
46 #define VCNL4035_DEV_ID_MASK		GENMASK(7, 0)
47 
48 /* Default values */
49 #define VCNL4035_MODE_ALS_ENABLE	BIT(0)
50 #define VCNL4035_MODE_ALS_DISABLE	0x00
51 #define VCNL4035_MODE_ALS_INT_ENABLE	BIT(1)
52 #define VCNL4035_MODE_ALS_INT_DISABLE	0
53 #define VCNL4035_DEV_ID_VAL		0x80
54 #define VCNL4035_ALS_IT_DEFAULT		0x01
55 #define VCNL4035_ALS_PERS_DEFAULT	0x00
56 #define VCNL4035_ALS_THDH_DEFAULT	5000
57 #define VCNL4035_ALS_THDL_DEFAULT	100
58 #define VCNL4035_SLEEP_DELAY_MS		2000
59 
60 struct vcnl4035_data {
61 	struct i2c_client *client;
62 	struct regmap *regmap;
63 	unsigned int als_it_val;
64 	unsigned int als_persistence;
65 	unsigned int als_thresh_low;
66 	unsigned int als_thresh_high;
67 	struct iio_trigger *drdy_trigger0;
68 };
69 
70 static inline bool vcnl4035_is_triggered(struct vcnl4035_data *data)
71 {
72 	int ret;
73 	int reg;
74 
75 	ret = regmap_read(data->regmap, VCNL4035_INT_FLAG, &reg);
76 	if (ret < 0)
77 		return false;
78 
79 	return !!(reg &
80 		(VCNL4035_INT_ALS_IF_H_MASK | VCNL4035_INT_ALS_IF_L_MASK));
81 }
82 
83 static irqreturn_t vcnl4035_drdy_irq_thread(int irq, void *private)
84 {
85 	struct iio_dev *indio_dev = private;
86 	struct vcnl4035_data *data = iio_priv(indio_dev);
87 
88 	if (vcnl4035_is_triggered(data)) {
89 		iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_LIGHT,
90 							0,
91 							IIO_EV_TYPE_THRESH,
92 							IIO_EV_DIR_EITHER),
93 				iio_get_time_ns(indio_dev));
94 		iio_trigger_poll_nested(data->drdy_trigger0);
95 		return IRQ_HANDLED;
96 	}
97 
98 	return IRQ_NONE;
99 }
100 
101 /* Triggered buffer */
102 static irqreturn_t vcnl4035_trigger_consumer_handler(int irq, void *p)
103 {
104 	struct iio_poll_func *pf = p;
105 	struct iio_dev *indio_dev = pf->indio_dev;
106 	struct vcnl4035_data *data = iio_priv(indio_dev);
107 	/* Ensure naturally aligned timestamp */
108 	u8 buffer[ALIGN(sizeof(u16), sizeof(s64)) + sizeof(s64)]  __aligned(8);
109 	int ret;
110 
111 	ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, (int *)buffer);
112 	if (ret < 0) {
113 		dev_err(&data->client->dev,
114 			"Trigger consumer can't read from sensor.\n");
115 		goto fail_read;
116 	}
117 	iio_push_to_buffers_with_timestamp(indio_dev, buffer,
118 					iio_get_time_ns(indio_dev));
119 
120 fail_read:
121 	iio_trigger_notify_done(indio_dev->trig);
122 
123 	return IRQ_HANDLED;
124 }
125 
126 static int vcnl4035_als_drdy_set_state(struct iio_trigger *trigger,
127 					bool enable_drdy)
128 {
129 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trigger);
130 	struct vcnl4035_data *data = iio_priv(indio_dev);
131 	int val = enable_drdy ? VCNL4035_MODE_ALS_INT_ENABLE :
132 					VCNL4035_MODE_ALS_INT_DISABLE;
133 
134 	return regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
135 				 VCNL4035_MODE_ALS_INT_MASK,
136 				 val);
137 }
138 
139 static const struct iio_trigger_ops vcnl4035_trigger_ops = {
140 	.validate_device = iio_trigger_validate_own_device,
141 	.set_trigger_state = vcnl4035_als_drdy_set_state,
142 };
143 
144 static int vcnl4035_set_pm_runtime_state(struct vcnl4035_data *data, bool on)
145 {
146 	int ret;
147 	struct device *dev = &data->client->dev;
148 
149 	if (on) {
150 		ret = pm_runtime_resume_and_get(dev);
151 	} else {
152 		pm_runtime_mark_last_busy(dev);
153 		ret = pm_runtime_put_autosuspend(dev);
154 	}
155 
156 	return ret;
157 }
158 
159 /*
160  *	Device IT	INT Time (ms)	Scale (lux/step)
161  *	000		50		0.064
162  *	001		100		0.032
163  *	010		200		0.016
164  *	100		400		0.008
165  *	101 - 111	800		0.004
166  * Values are proportional, so ALS INT is selected for input due to
167  * simplicity reason. Integration time value and scaling is
168  * calculated based on device INT value
169  *
170  * Raw value needs to be scaled using ALS steps
171  */
172 static int vcnl4035_read_raw(struct iio_dev *indio_dev,
173 			    struct iio_chan_spec const *chan, int *val,
174 			    int *val2, long mask)
175 {
176 	struct vcnl4035_data *data = iio_priv(indio_dev);
177 	int ret;
178 	int raw_data;
179 	unsigned int reg;
180 
181 	switch (mask) {
182 	case IIO_CHAN_INFO_RAW:
183 		ret = vcnl4035_set_pm_runtime_state(data, true);
184 		if  (ret < 0)
185 			return ret;
186 
187 		ret = iio_device_claim_direct_mode(indio_dev);
188 		if (!ret) {
189 			if (chan->channel)
190 				reg = VCNL4035_ALS_DATA;
191 			else
192 				reg = VCNL4035_WHITE_DATA;
193 			ret = regmap_read(data->regmap, reg, &raw_data);
194 			iio_device_release_direct_mode(indio_dev);
195 			if (!ret) {
196 				*val = raw_data;
197 				ret = IIO_VAL_INT;
198 			}
199 		}
200 		vcnl4035_set_pm_runtime_state(data, false);
201 		return ret;
202 	case IIO_CHAN_INFO_INT_TIME:
203 		*val = 50;
204 		if (data->als_it_val)
205 			*val = data->als_it_val * 100;
206 		return IIO_VAL_INT;
207 	case IIO_CHAN_INFO_SCALE:
208 		*val = 64;
209 		if (!data->als_it_val)
210 			*val2 = 1000;
211 		else
212 			*val2 = data->als_it_val * 2 * 1000;
213 		return IIO_VAL_FRACTIONAL;
214 	default:
215 		return -EINVAL;
216 	}
217 }
218 
219 static int vcnl4035_write_raw(struct iio_dev *indio_dev,
220 				struct iio_chan_spec const *chan,
221 				int val, int val2, long mask)
222 {
223 	int ret;
224 	struct vcnl4035_data *data = iio_priv(indio_dev);
225 
226 	switch (mask) {
227 	case IIO_CHAN_INFO_INT_TIME:
228 		if (val <= 0 || val > 800)
229 			return -EINVAL;
230 
231 		ret = vcnl4035_set_pm_runtime_state(data, true);
232 		if  (ret < 0)
233 			return ret;
234 
235 		ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
236 					 VCNL4035_ALS_IT_MASK,
237 					 val / 100);
238 		if (!ret)
239 			data->als_it_val = val / 100;
240 
241 		vcnl4035_set_pm_runtime_state(data, false);
242 		return ret;
243 	default:
244 		return -EINVAL;
245 	}
246 }
247 
248 /* No direct ABI for persistence and threshold, so eventing */
249 static int vcnl4035_read_thresh(struct iio_dev *indio_dev,
250 		const struct iio_chan_spec *chan, enum iio_event_type type,
251 		enum iio_event_direction dir, enum iio_event_info info,
252 		int *val, int *val2)
253 {
254 	struct vcnl4035_data *data = iio_priv(indio_dev);
255 
256 	switch (info) {
257 	case IIO_EV_INFO_VALUE:
258 		switch (dir) {
259 		case IIO_EV_DIR_RISING:
260 			*val = data->als_thresh_high;
261 			return IIO_VAL_INT;
262 		case IIO_EV_DIR_FALLING:
263 			*val = data->als_thresh_low;
264 			return IIO_VAL_INT;
265 		default:
266 			return -EINVAL;
267 		}
268 		break;
269 	case IIO_EV_INFO_PERIOD:
270 		*val = data->als_persistence;
271 		return IIO_VAL_INT;
272 	default:
273 		return -EINVAL;
274 	}
275 
276 }
277 
278 static int vcnl4035_write_thresh(struct iio_dev *indio_dev,
279 		const struct iio_chan_spec *chan, enum iio_event_type type,
280 		enum iio_event_direction dir, enum iio_event_info info, int val,
281 		int val2)
282 {
283 	struct vcnl4035_data *data = iio_priv(indio_dev);
284 	int ret;
285 
286 	switch (info) {
287 	case IIO_EV_INFO_VALUE:
288 		/* 16 bit threshold range 0 - 65535 */
289 		if (val < 0 || val > 65535)
290 			return -EINVAL;
291 		if (dir == IIO_EV_DIR_RISING) {
292 			if (val < data->als_thresh_low)
293 				return -EINVAL;
294 			ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
295 					   val);
296 			if (ret)
297 				return ret;
298 			data->als_thresh_high = val;
299 		} else {
300 			if (val > data->als_thresh_high)
301 				return -EINVAL;
302 			ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
303 					   val);
304 			if (ret)
305 				return ret;
306 			data->als_thresh_low = val;
307 		}
308 		return ret;
309 	case IIO_EV_INFO_PERIOD:
310 		/* allow only 1 2 4 8 as persistence value */
311 		if (val < 0 || val > 8 || hweight8(val) != 1)
312 			return -EINVAL;
313 		ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
314 					 VCNL4035_ALS_PERS_MASK, val);
315 		if (!ret)
316 			data->als_persistence = val;
317 		return ret;
318 	default:
319 		return -EINVAL;
320 	}
321 }
322 
323 static IIO_CONST_ATTR_INT_TIME_AVAIL("50 100 200 400 800");
324 
325 static struct attribute *vcnl4035_attributes[] = {
326 	&iio_const_attr_integration_time_available.dev_attr.attr,
327 	NULL,
328 };
329 
330 static const struct attribute_group vcnl4035_attribute_group = {
331 	.attrs = vcnl4035_attributes,
332 };
333 
334 static const struct iio_info vcnl4035_info = {
335 	.read_raw		= vcnl4035_read_raw,
336 	.write_raw		= vcnl4035_write_raw,
337 	.read_event_value	= vcnl4035_read_thresh,
338 	.write_event_value	= vcnl4035_write_thresh,
339 	.attrs			= &vcnl4035_attribute_group,
340 };
341 
342 static const struct iio_event_spec vcnl4035_event_spec[] = {
343 	{
344 		.type = IIO_EV_TYPE_THRESH,
345 		.dir = IIO_EV_DIR_RISING,
346 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
347 	}, {
348 		.type = IIO_EV_TYPE_THRESH,
349 		.dir = IIO_EV_DIR_FALLING,
350 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
351 	}, {
352 		.type = IIO_EV_TYPE_THRESH,
353 		.dir = IIO_EV_DIR_EITHER,
354 		.mask_separate = BIT(IIO_EV_INFO_PERIOD),
355 	},
356 };
357 
358 enum vcnl4035_scan_index_order {
359 	VCNL4035_CHAN_INDEX_LIGHT,
360 	VCNL4035_CHAN_INDEX_WHITE_LED,
361 };
362 
363 static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
364 	.validate_scan_mask = &iio_validate_scan_mask_onehot,
365 };
366 
367 static const struct iio_chan_spec vcnl4035_channels[] = {
368 	{
369 		.type = IIO_LIGHT,
370 		.channel = 0,
371 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
372 				BIT(IIO_CHAN_INFO_INT_TIME) |
373 				BIT(IIO_CHAN_INFO_SCALE),
374 		.event_spec = vcnl4035_event_spec,
375 		.num_event_specs = ARRAY_SIZE(vcnl4035_event_spec),
376 		.scan_index = VCNL4035_CHAN_INDEX_LIGHT,
377 		.scan_type = {
378 			.sign = 'u',
379 			.realbits = 16,
380 			.storagebits = 16,
381 			.endianness = IIO_LE,
382 		},
383 	},
384 	{
385 		.type = IIO_INTENSITY,
386 		.channel = 1,
387 		.modified = 1,
388 		.channel2 = IIO_MOD_LIGHT_BOTH,
389 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
390 		.scan_index = VCNL4035_CHAN_INDEX_WHITE_LED,
391 		.scan_type = {
392 			.sign = 'u',
393 			.realbits = 16,
394 			.storagebits = 16,
395 			.endianness = IIO_LE,
396 		},
397 	},
398 };
399 
400 static int vcnl4035_set_als_power_state(struct vcnl4035_data *data, u8 status)
401 {
402 	return regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
403 					VCNL4035_MODE_ALS_MASK,
404 					status);
405 }
406 
407 static int vcnl4035_init(struct vcnl4035_data *data)
408 {
409 	int ret;
410 	int id;
411 
412 	ret = regmap_read(data->regmap, VCNL4035_DEV_ID, &id);
413 	if (ret < 0) {
414 		dev_err(&data->client->dev, "Failed to read DEV_ID register\n");
415 		return ret;
416 	}
417 
418 	id = FIELD_GET(VCNL4035_DEV_ID_MASK, id);
419 	if (id != VCNL4035_DEV_ID_VAL) {
420 		dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
421 			id, VCNL4035_DEV_ID_VAL);
422 		return -ENODEV;
423 	}
424 
425 	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
426 	if (ret < 0)
427 		return ret;
428 
429 	/* ALS white channel enable */
430 	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
431 				 VCNL4035_MODE_ALS_WHITE_CHAN,
432 				 1);
433 	if (ret) {
434 		dev_err(&data->client->dev, "set white channel enable %d\n",
435 			ret);
436 		return ret;
437 	}
438 
439 	/* set default integration time - 100 ms for ALS */
440 	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
441 				 VCNL4035_ALS_IT_MASK,
442 				 VCNL4035_ALS_IT_DEFAULT);
443 	if (ret) {
444 		dev_err(&data->client->dev, "set default ALS IT returned %d\n",
445 			ret);
446 		return ret;
447 	}
448 	data->als_it_val = VCNL4035_ALS_IT_DEFAULT;
449 
450 	/* set default persistence time - 1 for ALS */
451 	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
452 				 VCNL4035_ALS_PERS_MASK,
453 				 VCNL4035_ALS_PERS_DEFAULT);
454 	if (ret) {
455 		dev_err(&data->client->dev, "set default PERS returned %d\n",
456 			ret);
457 		return ret;
458 	}
459 	data->als_persistence = VCNL4035_ALS_PERS_DEFAULT;
460 
461 	/* set default HIGH threshold for ALS */
462 	ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
463 				VCNL4035_ALS_THDH_DEFAULT);
464 	if (ret) {
465 		dev_err(&data->client->dev, "set default THDH returned %d\n",
466 			ret);
467 		return ret;
468 	}
469 	data->als_thresh_high = VCNL4035_ALS_THDH_DEFAULT;
470 
471 	/* set default LOW threshold for ALS */
472 	ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
473 				VCNL4035_ALS_THDL_DEFAULT);
474 	if (ret) {
475 		dev_err(&data->client->dev, "set default THDL returned %d\n",
476 			ret);
477 		return ret;
478 	}
479 	data->als_thresh_low = VCNL4035_ALS_THDL_DEFAULT;
480 
481 	return 0;
482 }
483 
484 static bool vcnl4035_is_volatile_reg(struct device *dev, unsigned int reg)
485 {
486 	switch (reg) {
487 	case VCNL4035_ALS_CONF:
488 	case VCNL4035_DEV_ID:
489 		return false;
490 	default:
491 		return true;
492 	}
493 }
494 
495 static const struct regmap_config vcnl4035_regmap_config = {
496 	.name		= VCNL4035_REGMAP_NAME,
497 	.reg_bits	= 8,
498 	.val_bits	= 16,
499 	.max_register	= VCNL4035_DEV_ID,
500 	.cache_type	= REGCACHE_RBTREE,
501 	.volatile_reg	= vcnl4035_is_volatile_reg,
502 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
503 };
504 
505 static int vcnl4035_probe_trigger(struct iio_dev *indio_dev)
506 {
507 	int ret;
508 	struct vcnl4035_data *data = iio_priv(indio_dev);
509 
510 	data->drdy_trigger0 = devm_iio_trigger_alloc(
511 			indio_dev->dev.parent,
512 			"%s-dev%d", indio_dev->name, iio_device_id(indio_dev));
513 	if (!data->drdy_trigger0)
514 		return -ENOMEM;
515 
516 	data->drdy_trigger0->ops = &vcnl4035_trigger_ops;
517 	iio_trigger_set_drvdata(data->drdy_trigger0, indio_dev);
518 	ret = devm_iio_trigger_register(indio_dev->dev.parent,
519 					data->drdy_trigger0);
520 	if (ret) {
521 		dev_err(&data->client->dev, "iio trigger register failed\n");
522 		return ret;
523 	}
524 
525 	/* Trigger setup */
526 	ret = devm_iio_triggered_buffer_setup(indio_dev->dev.parent, indio_dev,
527 					NULL, vcnl4035_trigger_consumer_handler,
528 					&iio_triggered_buffer_setup_ops);
529 	if (ret < 0) {
530 		dev_err(&data->client->dev, "iio triggered buffer setup failed\n");
531 		return ret;
532 	}
533 
534 	/* IRQ to trigger mapping */
535 	ret = devm_request_threaded_irq(&data->client->dev, data->client->irq,
536 			NULL, vcnl4035_drdy_irq_thread,
537 			IRQF_TRIGGER_LOW | IRQF_ONESHOT,
538 			VCNL4035_IRQ_NAME, indio_dev);
539 	if (ret < 0)
540 		dev_err(&data->client->dev, "request irq %d for trigger0 failed\n",
541 				data->client->irq);
542 	return ret;
543 }
544 
545 static int vcnl4035_probe(struct i2c_client *client)
546 {
547 	struct vcnl4035_data *data;
548 	struct iio_dev *indio_dev;
549 	struct regmap *regmap;
550 	int ret;
551 
552 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
553 	if (!indio_dev)
554 		return -ENOMEM;
555 
556 	regmap = devm_regmap_init_i2c(client, &vcnl4035_regmap_config);
557 	if (IS_ERR(regmap)) {
558 		dev_err(&client->dev, "regmap_init failed!\n");
559 		return PTR_ERR(regmap);
560 	}
561 
562 	data = iio_priv(indio_dev);
563 	i2c_set_clientdata(client, indio_dev);
564 	data->client = client;
565 	data->regmap = regmap;
566 
567 	indio_dev->info = &vcnl4035_info;
568 	indio_dev->name = VCNL4035_DRV_NAME;
569 	indio_dev->channels = vcnl4035_channels;
570 	indio_dev->num_channels = ARRAY_SIZE(vcnl4035_channels);
571 	indio_dev->modes = INDIO_DIRECT_MODE;
572 
573 	ret = vcnl4035_init(data);
574 	if (ret < 0) {
575 		dev_err(&client->dev, "vcnl4035 chip init failed\n");
576 		return ret;
577 	}
578 
579 	if (client->irq > 0) {
580 		ret = vcnl4035_probe_trigger(indio_dev);
581 		if (ret < 0) {
582 			dev_err(&client->dev, "vcnl4035 unable init trigger\n");
583 			goto fail_poweroff;
584 		}
585 	}
586 
587 	ret = pm_runtime_set_active(&client->dev);
588 	if (ret < 0)
589 		goto fail_poweroff;
590 
591 	ret = iio_device_register(indio_dev);
592 	if (ret < 0)
593 		goto fail_poweroff;
594 
595 	pm_runtime_enable(&client->dev);
596 	pm_runtime_set_autosuspend_delay(&client->dev, VCNL4035_SLEEP_DELAY_MS);
597 	pm_runtime_use_autosuspend(&client->dev);
598 
599 	return 0;
600 
601 fail_poweroff:
602 	vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
603 	return ret;
604 }
605 
606 static void vcnl4035_remove(struct i2c_client *client)
607 {
608 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
609 	int ret;
610 
611 	pm_runtime_dont_use_autosuspend(&client->dev);
612 	pm_runtime_disable(&client->dev);
613 	iio_device_unregister(indio_dev);
614 	pm_runtime_set_suspended(&client->dev);
615 
616 	ret = vcnl4035_set_als_power_state(iio_priv(indio_dev),
617 					   VCNL4035_MODE_ALS_DISABLE);
618 	if (ret)
619 		dev_warn(&client->dev, "Failed to put device into standby (%pe)\n",
620 			 ERR_PTR(ret));
621 }
622 
623 static int vcnl4035_runtime_suspend(struct device *dev)
624 {
625 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
626 	struct vcnl4035_data *data = iio_priv(indio_dev);
627 	int ret;
628 
629 	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
630 	regcache_mark_dirty(data->regmap);
631 
632 	return ret;
633 }
634 
635 static int vcnl4035_runtime_resume(struct device *dev)
636 {
637 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
638 	struct vcnl4035_data *data = iio_priv(indio_dev);
639 	int ret;
640 
641 	regcache_sync(data->regmap);
642 	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
643 	if (ret < 0)
644 		return ret;
645 
646 	/* wait for 1 ALS integration cycle */
647 	msleep(data->als_it_val * 100);
648 
649 	return 0;
650 }
651 
652 static DEFINE_RUNTIME_DEV_PM_OPS(vcnl4035_pm_ops, vcnl4035_runtime_suspend,
653 				 vcnl4035_runtime_resume, NULL);
654 
655 static const struct i2c_device_id vcnl4035_id[] = {
656 	{ "vcnl4035", 0 },
657 	{ }
658 };
659 MODULE_DEVICE_TABLE(i2c, vcnl4035_id);
660 
661 static const struct of_device_id vcnl4035_of_match[] = {
662 	{ .compatible = "vishay,vcnl4035", },
663 	{ }
664 };
665 MODULE_DEVICE_TABLE(of, vcnl4035_of_match);
666 
667 static struct i2c_driver vcnl4035_driver = {
668 	.driver = {
669 		.name   = VCNL4035_DRV_NAME,
670 		.pm	= pm_ptr(&vcnl4035_pm_ops),
671 		.of_match_table = vcnl4035_of_match,
672 	},
673 	.probe = vcnl4035_probe,
674 	.remove	= vcnl4035_remove,
675 	.id_table = vcnl4035_id,
676 };
677 
678 module_i2c_driver(vcnl4035_driver);
679 
680 MODULE_AUTHOR("Parthiban Nallathambi <pn@denx.de>");
681 MODULE_DESCRIPTION("VCNL4035 Ambient Light Sensor driver");
682 MODULE_LICENSE("GPL v2");
683