xref: /linux/drivers/iio/light/stk3310.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /**
2  * Sensortek STK3310/STK3311 Ambient Light and Proximity Sensor
3  *
4  * Copyright (c) 2015, Intel Corporation.
5  *
6  * This file is subject to the terms and conditions of version 2 of
7  * the GNU General Public License. See the file COPYING in the main
8  * directory of this archive for more details.
9  *
10  * IIO driver for STK3310/STK3311. 7-bit I2C address: 0x48.
11  */
12 
13 #include <linux/acpi.h>
14 #include <linux/i2c.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/regmap.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/iio/events.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 
24 #define STK3310_REG_STATE			0x00
25 #define STK3310_REG_PSCTRL			0x01
26 #define STK3310_REG_ALSCTRL			0x02
27 #define STK3310_REG_INT				0x04
28 #define STK3310_REG_THDH_PS			0x06
29 #define STK3310_REG_THDL_PS			0x08
30 #define STK3310_REG_FLAG			0x10
31 #define STK3310_REG_PS_DATA_MSB			0x11
32 #define STK3310_REG_PS_DATA_LSB			0x12
33 #define STK3310_REG_ALS_DATA_MSB		0x13
34 #define STK3310_REG_ALS_DATA_LSB		0x14
35 #define STK3310_REG_ID				0x3E
36 #define STK3310_MAX_REG				0x80
37 
38 #define STK3310_STATE_EN_PS			0x01
39 #define STK3310_STATE_EN_ALS			0x02
40 #define STK3310_STATE_STANDBY			0x00
41 
42 #define STK3310_CHIP_ID_VAL			0x13
43 #define STK3311_CHIP_ID_VAL			0x1D
44 #define STK3310_PSINT_EN			0x01
45 #define STK3310_PS_MAX_VAL			0xFFFF
46 
47 #define STK3310_DRIVER_NAME			"stk3310"
48 #define STK3310_REGMAP_NAME			"stk3310_regmap"
49 #define STK3310_EVENT				"stk3310_event"
50 #define STK3310_GPIO				"stk3310_gpio"
51 
52 #define STK3310_SCALE_AVAILABLE			"6.4 1.6 0.4 0.1"
53 
54 #define STK3310_IT_AVAILABLE \
55 	"0.000185 0.000370 0.000741 0.001480 0.002960 0.005920 0.011840 " \
56 	"0.023680 0.047360 0.094720 0.189440 0.378880 0.757760 1.515520 " \
57 	"3.031040 6.062080"
58 
59 #define STK3310_REGFIELD(name)						    \
60 	do {								    \
61 		data->reg_##name =					    \
62 			devm_regmap_field_alloc(&client->dev, regmap,	    \
63 				stk3310_reg_field_##name);		    \
64 		if (IS_ERR(data->reg_##name)) {				    \
65 			dev_err(&client->dev, "reg field alloc failed.\n"); \
66 			return PTR_ERR(data->reg_##name);		    \
67 		}							    \
68 	} while (0)
69 
70 static const struct reg_field stk3310_reg_field_state =
71 				REG_FIELD(STK3310_REG_STATE, 0, 2);
72 static const struct reg_field stk3310_reg_field_als_gain =
73 				REG_FIELD(STK3310_REG_ALSCTRL, 4, 5);
74 static const struct reg_field stk3310_reg_field_ps_gain =
75 				REG_FIELD(STK3310_REG_PSCTRL, 4, 5);
76 static const struct reg_field stk3310_reg_field_als_it =
77 				REG_FIELD(STK3310_REG_ALSCTRL, 0, 3);
78 static const struct reg_field stk3310_reg_field_ps_it =
79 				REG_FIELD(STK3310_REG_PSCTRL, 0, 3);
80 static const struct reg_field stk3310_reg_field_int_ps =
81 				REG_FIELD(STK3310_REG_INT, 0, 2);
82 static const struct reg_field stk3310_reg_field_flag_psint =
83 				REG_FIELD(STK3310_REG_FLAG, 4, 4);
84 static const struct reg_field stk3310_reg_field_flag_nf =
85 				REG_FIELD(STK3310_REG_FLAG, 0, 0);
86 
87 /* Estimate maximum proximity values with regard to measurement scale. */
88 static const int stk3310_ps_max[4] = {
89 	STK3310_PS_MAX_VAL / 640,
90 	STK3310_PS_MAX_VAL / 160,
91 	STK3310_PS_MAX_VAL /  40,
92 	STK3310_PS_MAX_VAL /  10
93 };
94 
95 static const int stk3310_scale_table[][2] = {
96 	{6, 400000}, {1, 600000}, {0, 400000}, {0, 100000}
97 };
98 
99 /* Integration time in seconds, microseconds */
100 static const int stk3310_it_table[][2] = {
101 	{0, 185},	{0, 370},	{0, 741},	{0, 1480},
102 	{0, 2960},	{0, 5920},	{0, 11840},	{0, 23680},
103 	{0, 47360},	{0, 94720},	{0, 189440},	{0, 378880},
104 	{0, 757760},	{1, 515520},	{3, 31040},	{6, 62080},
105 };
106 
107 struct stk3310_data {
108 	struct i2c_client *client;
109 	struct mutex lock;
110 	bool als_enabled;
111 	bool ps_enabled;
112 	u64 timestamp;
113 	struct regmap *regmap;
114 	struct regmap_field *reg_state;
115 	struct regmap_field *reg_als_gain;
116 	struct regmap_field *reg_ps_gain;
117 	struct regmap_field *reg_als_it;
118 	struct regmap_field *reg_ps_it;
119 	struct regmap_field *reg_int_ps;
120 	struct regmap_field *reg_flag_psint;
121 	struct regmap_field *reg_flag_nf;
122 };
123 
124 static const struct iio_event_spec stk3310_events[] = {
125 	/* Proximity event */
126 	{
127 		.type = IIO_EV_TYPE_THRESH,
128 		.dir = IIO_EV_DIR_RISING,
129 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
130 				 BIT(IIO_EV_INFO_ENABLE),
131 	},
132 	/* Out-of-proximity event */
133 	{
134 		.type = IIO_EV_TYPE_THRESH,
135 		.dir = IIO_EV_DIR_FALLING,
136 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
137 				 BIT(IIO_EV_INFO_ENABLE),
138 	},
139 };
140 
141 static const struct iio_chan_spec stk3310_channels[] = {
142 	{
143 		.type = IIO_LIGHT,
144 		.info_mask_separate =
145 			BIT(IIO_CHAN_INFO_RAW) |
146 			BIT(IIO_CHAN_INFO_SCALE) |
147 			BIT(IIO_CHAN_INFO_INT_TIME),
148 	},
149 	{
150 		.type = IIO_PROXIMITY,
151 		.info_mask_separate =
152 			BIT(IIO_CHAN_INFO_RAW) |
153 			BIT(IIO_CHAN_INFO_SCALE) |
154 			BIT(IIO_CHAN_INFO_INT_TIME),
155 		.event_spec = stk3310_events,
156 		.num_event_specs = ARRAY_SIZE(stk3310_events),
157 	}
158 };
159 
160 static IIO_CONST_ATTR(in_illuminance_scale_available, STK3310_SCALE_AVAILABLE);
161 
162 static IIO_CONST_ATTR(in_proximity_scale_available, STK3310_SCALE_AVAILABLE);
163 
164 static IIO_CONST_ATTR(in_illuminance_integration_time_available,
165 		      STK3310_IT_AVAILABLE);
166 
167 static IIO_CONST_ATTR(in_proximity_integration_time_available,
168 		      STK3310_IT_AVAILABLE);
169 
170 static struct attribute *stk3310_attributes[] = {
171 	&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
172 	&iio_const_attr_in_proximity_scale_available.dev_attr.attr,
173 	&iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
174 	&iio_const_attr_in_proximity_integration_time_available.dev_attr.attr,
175 	NULL,
176 };
177 
178 static const struct attribute_group stk3310_attribute_group = {
179 	.attrs = stk3310_attributes
180 };
181 
182 static int stk3310_get_index(const int table[][2], int table_size,
183 			     int val, int val2)
184 {
185 	int i;
186 
187 	for (i = 0; i < table_size; i++) {
188 		if (val == table[i][0] && val2 == table[i][1])
189 			return i;
190 	}
191 
192 	return -EINVAL;
193 }
194 
195 static int stk3310_read_event(struct iio_dev *indio_dev,
196 			      const struct iio_chan_spec *chan,
197 			      enum iio_event_type type,
198 			      enum iio_event_direction dir,
199 			      enum iio_event_info info,
200 			      int *val, int *val2)
201 {
202 	u8 reg;
203 	__be16 buf;
204 	int ret;
205 	struct stk3310_data *data = iio_priv(indio_dev);
206 
207 	if (info != IIO_EV_INFO_VALUE)
208 		return -EINVAL;
209 
210 	/* Only proximity interrupts are implemented at the moment. */
211 	if (dir == IIO_EV_DIR_RISING)
212 		reg = STK3310_REG_THDH_PS;
213 	else if (dir == IIO_EV_DIR_FALLING)
214 		reg = STK3310_REG_THDL_PS;
215 	else
216 		return -EINVAL;
217 
218 	mutex_lock(&data->lock);
219 	ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
220 	mutex_unlock(&data->lock);
221 	if (ret < 0) {
222 		dev_err(&data->client->dev, "register read failed\n");
223 		return ret;
224 	}
225 	*val = be16_to_cpu(buf);
226 
227 	return IIO_VAL_INT;
228 }
229 
230 static int stk3310_write_event(struct iio_dev *indio_dev,
231 			       const struct iio_chan_spec *chan,
232 			       enum iio_event_type type,
233 			       enum iio_event_direction dir,
234 			       enum iio_event_info info,
235 			       int val, int val2)
236 {
237 	u8 reg;
238 	__be16 buf;
239 	int ret;
240 	unsigned int index;
241 	struct stk3310_data *data = iio_priv(indio_dev);
242 	struct i2c_client *client = data->client;
243 
244 	regmap_field_read(data->reg_ps_gain, &index);
245 	if (val > stk3310_ps_max[index])
246 		return -EINVAL;
247 
248 	if (dir == IIO_EV_DIR_RISING)
249 		reg = STK3310_REG_THDH_PS;
250 	else if (dir == IIO_EV_DIR_FALLING)
251 		reg = STK3310_REG_THDL_PS;
252 	else
253 		return -EINVAL;
254 
255 	buf = cpu_to_be16(val);
256 	ret = regmap_bulk_write(data->regmap, reg, &buf, 2);
257 	if (ret < 0)
258 		dev_err(&client->dev, "failed to set PS threshold!\n");
259 
260 	return ret;
261 }
262 
263 static int stk3310_read_event_config(struct iio_dev *indio_dev,
264 				     const struct iio_chan_spec *chan,
265 				     enum iio_event_type type,
266 				     enum iio_event_direction dir)
267 {
268 	unsigned int event_val;
269 	struct stk3310_data *data = iio_priv(indio_dev);
270 
271 	regmap_field_read(data->reg_int_ps, &event_val);
272 
273 	return event_val;
274 }
275 
276 static int stk3310_write_event_config(struct iio_dev *indio_dev,
277 				      const struct iio_chan_spec *chan,
278 				      enum iio_event_type type,
279 				      enum iio_event_direction dir,
280 				      int state)
281 {
282 	int ret;
283 	struct stk3310_data *data = iio_priv(indio_dev);
284 	struct i2c_client *client = data->client;
285 
286 	if (state < 0 || state > 7)
287 		return -EINVAL;
288 
289 	/* Set INT_PS value */
290 	mutex_lock(&data->lock);
291 	ret = regmap_field_write(data->reg_int_ps, state);
292 	if (ret < 0)
293 		dev_err(&client->dev, "failed to set interrupt mode\n");
294 	mutex_unlock(&data->lock);
295 
296 	return ret;
297 }
298 
299 static int stk3310_read_raw(struct iio_dev *indio_dev,
300 			    struct iio_chan_spec const *chan,
301 			    int *val, int *val2, long mask)
302 {
303 	u8 reg;
304 	__be16 buf;
305 	int ret;
306 	unsigned int index;
307 	struct stk3310_data *data = iio_priv(indio_dev);
308 	struct i2c_client *client = data->client;
309 
310 	switch (mask) {
311 	case IIO_CHAN_INFO_RAW:
312 		if (chan->type == IIO_LIGHT)
313 			reg = STK3310_REG_ALS_DATA_MSB;
314 		else if (chan->type == IIO_PROXIMITY)
315 			reg = STK3310_REG_PS_DATA_MSB;
316 		else
317 			return -EINVAL;
318 		mutex_lock(&data->lock);
319 		ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
320 		if (ret < 0) {
321 			dev_err(&client->dev, "register read failed\n");
322 			mutex_unlock(&data->lock);
323 			return ret;
324 		}
325 		*val = be16_to_cpu(buf);
326 		mutex_unlock(&data->lock);
327 		return IIO_VAL_INT;
328 	case IIO_CHAN_INFO_INT_TIME:
329 		if (chan->type == IIO_LIGHT)
330 			regmap_field_read(data->reg_als_it, &index);
331 		else
332 			regmap_field_read(data->reg_ps_it, &index);
333 		*val = stk3310_it_table[index][0];
334 		*val2 = stk3310_it_table[index][1];
335 		return IIO_VAL_INT_PLUS_MICRO;
336 	case IIO_CHAN_INFO_SCALE:
337 		if (chan->type == IIO_LIGHT)
338 			regmap_field_read(data->reg_als_gain, &index);
339 		else
340 			regmap_field_read(data->reg_ps_gain, &index);
341 		*val = stk3310_scale_table[index][0];
342 		*val2 = stk3310_scale_table[index][1];
343 		return IIO_VAL_INT_PLUS_MICRO;
344 	}
345 
346 	return -EINVAL;
347 }
348 
349 static int stk3310_write_raw(struct iio_dev *indio_dev,
350 			     struct iio_chan_spec const *chan,
351 			     int val, int val2, long mask)
352 {
353 	int ret;
354 	int index;
355 	struct stk3310_data *data = iio_priv(indio_dev);
356 
357 	switch (mask) {
358 	case IIO_CHAN_INFO_INT_TIME:
359 		index = stk3310_get_index(stk3310_it_table,
360 					  ARRAY_SIZE(stk3310_it_table),
361 					  val, val2);
362 		if (index < 0)
363 			return -EINVAL;
364 		mutex_lock(&data->lock);
365 		if (chan->type == IIO_LIGHT)
366 			ret = regmap_field_write(data->reg_als_it, index);
367 		else
368 			ret = regmap_field_write(data->reg_ps_it, index);
369 		if (ret < 0)
370 			dev_err(&data->client->dev,
371 					"sensor configuration failed\n");
372 		mutex_unlock(&data->lock);
373 		return ret;
374 
375 	case IIO_CHAN_INFO_SCALE:
376 		index = stk3310_get_index(stk3310_scale_table,
377 					  ARRAY_SIZE(stk3310_scale_table),
378 					  val, val2);
379 		if (index < 0)
380 			return -EINVAL;
381 		mutex_lock(&data->lock);
382 		if (chan->type == IIO_LIGHT)
383 			ret = regmap_field_write(data->reg_als_gain, index);
384 		else
385 			ret = regmap_field_write(data->reg_ps_gain, index);
386 		if (ret < 0)
387 			dev_err(&data->client->dev,
388 					"sensor configuration failed\n");
389 		mutex_unlock(&data->lock);
390 		return ret;
391 	}
392 
393 	return -EINVAL;
394 }
395 
396 static const struct iio_info stk3310_info = {
397 	.driver_module		= THIS_MODULE,
398 	.read_raw		= stk3310_read_raw,
399 	.write_raw		= stk3310_write_raw,
400 	.attrs			= &stk3310_attribute_group,
401 	.read_event_value	= stk3310_read_event,
402 	.write_event_value	= stk3310_write_event,
403 	.read_event_config	= stk3310_read_event_config,
404 	.write_event_config	= stk3310_write_event_config,
405 };
406 
407 static int stk3310_set_state(struct stk3310_data *data, u8 state)
408 {
409 	int ret;
410 	struct i2c_client *client = data->client;
411 
412 	/* 3-bit state; 0b100 is not supported. */
413 	if (state > 7 || state == 4)
414 		return -EINVAL;
415 
416 	mutex_lock(&data->lock);
417 	ret = regmap_field_write(data->reg_state, state);
418 	if (ret < 0) {
419 		dev_err(&client->dev, "failed to change sensor state\n");
420 	} else if (state != STK3310_STATE_STANDBY) {
421 		/* Don't reset the 'enabled' flags if we're going in standby */
422 		data->ps_enabled  = !!(state & 0x01);
423 		data->als_enabled = !!(state & 0x02);
424 	}
425 	mutex_unlock(&data->lock);
426 
427 	return ret;
428 }
429 
430 static int stk3310_init(struct iio_dev *indio_dev)
431 {
432 	int ret;
433 	int chipid;
434 	u8 state;
435 	struct stk3310_data *data = iio_priv(indio_dev);
436 	struct i2c_client *client = data->client;
437 
438 	regmap_read(data->regmap, STK3310_REG_ID, &chipid);
439 	if (chipid != STK3310_CHIP_ID_VAL &&
440 	    chipid != STK3311_CHIP_ID_VAL) {
441 		dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
442 		return -ENODEV;
443 	}
444 
445 	state = STK3310_STATE_EN_ALS | STK3310_STATE_EN_PS;
446 	ret = stk3310_set_state(data, state);
447 	if (ret < 0) {
448 		dev_err(&client->dev, "failed to enable sensor");
449 		return ret;
450 	}
451 
452 	/* Enable PS interrupts */
453 	ret = regmap_field_write(data->reg_int_ps, STK3310_PSINT_EN);
454 	if (ret < 0)
455 		dev_err(&client->dev, "failed to enable interrupts!\n");
456 
457 	return ret;
458 }
459 
460 static int stk3310_gpio_probe(struct i2c_client *client)
461 {
462 	struct device *dev;
463 	struct gpio_desc *gpio;
464 	int ret;
465 
466 	if (!client)
467 		return -EINVAL;
468 
469 	dev = &client->dev;
470 
471 	/* gpio interrupt pin */
472 	gpio = devm_gpiod_get_index(dev, STK3310_GPIO, 0);
473 	if (IS_ERR(gpio)) {
474 		dev_err(dev, "acpi gpio get index failed\n");
475 		return PTR_ERR(gpio);
476 	}
477 
478 	ret = gpiod_direction_input(gpio);
479 	if (ret)
480 		return ret;
481 
482 	ret = gpiod_to_irq(gpio);
483 	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
484 
485 	return ret;
486 }
487 
488 static bool stk3310_is_volatile_reg(struct device *dev, unsigned int reg)
489 {
490 	switch (reg) {
491 	case STK3310_REG_ALS_DATA_MSB:
492 	case STK3310_REG_ALS_DATA_LSB:
493 	case STK3310_REG_PS_DATA_LSB:
494 	case STK3310_REG_PS_DATA_MSB:
495 	case STK3310_REG_FLAG:
496 		return true;
497 	default:
498 		return false;
499 	}
500 }
501 
502 static struct regmap_config stk3310_regmap_config = {
503 	.name = STK3310_REGMAP_NAME,
504 	.reg_bits = 8,
505 	.val_bits = 8,
506 	.max_register = STK3310_MAX_REG,
507 	.cache_type = REGCACHE_RBTREE,
508 	.volatile_reg = stk3310_is_volatile_reg,
509 };
510 
511 static int stk3310_regmap_init(struct stk3310_data *data)
512 {
513 	struct regmap *regmap;
514 	struct i2c_client *client;
515 
516 	client = data->client;
517 	regmap = devm_regmap_init_i2c(client, &stk3310_regmap_config);
518 	if (IS_ERR(regmap)) {
519 		dev_err(&client->dev, "regmap initialization failed.\n");
520 		return PTR_ERR(regmap);
521 	}
522 	data->regmap = regmap;
523 
524 	STK3310_REGFIELD(state);
525 	STK3310_REGFIELD(als_gain);
526 	STK3310_REGFIELD(ps_gain);
527 	STK3310_REGFIELD(als_it);
528 	STK3310_REGFIELD(ps_it);
529 	STK3310_REGFIELD(int_ps);
530 	STK3310_REGFIELD(flag_psint);
531 	STK3310_REGFIELD(flag_nf);
532 
533 	return 0;
534 }
535 
536 static irqreturn_t stk3310_irq_handler(int irq, void *private)
537 {
538 	struct iio_dev *indio_dev = private;
539 	struct stk3310_data *data = iio_priv(indio_dev);
540 
541 	data->timestamp = iio_get_time_ns();
542 
543 	return IRQ_WAKE_THREAD;
544 }
545 
546 static irqreturn_t stk3310_irq_event_handler(int irq, void *private)
547 {
548 	int ret;
549 	unsigned int dir;
550 	u64 event;
551 
552 	struct iio_dev *indio_dev = private;
553 	struct stk3310_data *data = iio_priv(indio_dev);
554 
555 	/* Read FLAG_NF to figure out what threshold has been met. */
556 	mutex_lock(&data->lock);
557 	ret = regmap_field_read(data->reg_flag_nf, &dir);
558 	if (ret < 0) {
559 		dev_err(&data->client->dev, "register read failed\n");
560 		mutex_unlock(&data->lock);
561 		return ret;
562 	}
563 	event = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 1,
564 				     IIO_EV_TYPE_THRESH,
565 				     (dir ? IIO_EV_DIR_FALLING :
566 					    IIO_EV_DIR_RISING));
567 	iio_push_event(indio_dev, event, data->timestamp);
568 
569 	/* Reset the interrupt flag */
570 	ret = regmap_field_write(data->reg_flag_psint, 0);
571 	if (ret < 0)
572 		dev_err(&data->client->dev, "failed to reset interrupts\n");
573 	mutex_unlock(&data->lock);
574 
575 	return IRQ_HANDLED;
576 }
577 
578 static int stk3310_probe(struct i2c_client *client,
579 			 const struct i2c_device_id *id)
580 {
581 	int ret;
582 	struct iio_dev *indio_dev;
583 	struct stk3310_data *data;
584 
585 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
586 	if (!indio_dev) {
587 		dev_err(&client->dev, "iio allocation failed!\n");
588 		return -ENOMEM;
589 	}
590 
591 	data = iio_priv(indio_dev);
592 	data->client = client;
593 	i2c_set_clientdata(client, indio_dev);
594 	mutex_init(&data->lock);
595 
596 	ret = stk3310_regmap_init(data);
597 	if (ret < 0)
598 		return ret;
599 
600 	indio_dev->dev.parent = &client->dev;
601 	indio_dev->info = &stk3310_info;
602 	indio_dev->name = STK3310_DRIVER_NAME;
603 	indio_dev->modes = INDIO_DIRECT_MODE;
604 	indio_dev->channels = stk3310_channels;
605 	indio_dev->num_channels = ARRAY_SIZE(stk3310_channels);
606 
607 	ret = stk3310_init(indio_dev);
608 	if (ret < 0)
609 		return ret;
610 
611 	if (client->irq < 0)
612 		client->irq = stk3310_gpio_probe(client);
613 
614 	if (client->irq >= 0) {
615 		ret = devm_request_threaded_irq(&client->dev, client->irq,
616 						stk3310_irq_handler,
617 						stk3310_irq_event_handler,
618 						IRQF_TRIGGER_FALLING |
619 						IRQF_ONESHOT,
620 						STK3310_EVENT, indio_dev);
621 		if (ret < 0)
622 			dev_err(&client->dev, "request irq %d failed\n",
623 					client->irq);
624 	}
625 
626 	ret = iio_device_register(indio_dev);
627 	if (ret < 0) {
628 		dev_err(&client->dev, "device_register failed\n");
629 		stk3310_set_state(data, STK3310_STATE_STANDBY);
630 	}
631 
632 	return ret;
633 }
634 
635 static int stk3310_remove(struct i2c_client *client)
636 {
637 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
638 
639 	iio_device_unregister(indio_dev);
640 	return stk3310_set_state(iio_priv(indio_dev), STK3310_STATE_STANDBY);
641 }
642 
643 #ifdef CONFIG_PM_SLEEP
644 static int stk3310_suspend(struct device *dev)
645 {
646 	struct stk3310_data *data;
647 
648 	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
649 
650 	return stk3310_set_state(data, STK3310_STATE_STANDBY);
651 }
652 
653 static int stk3310_resume(struct device *dev)
654 {
655 	int state = 0;
656 	struct stk3310_data *data;
657 
658 	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
659 	if (data->ps_enabled)
660 		state |= STK3310_STATE_EN_PS;
661 	if (data->als_enabled)
662 		state |= STK3310_STATE_EN_ALS;
663 
664 	return stk3310_set_state(data, state);
665 }
666 
667 static SIMPLE_DEV_PM_OPS(stk3310_pm_ops, stk3310_suspend, stk3310_resume);
668 
669 #define STK3310_PM_OPS (&stk3310_pm_ops)
670 #else
671 #define STK3310_PM_OPS NULL
672 #endif
673 
674 static const struct i2c_device_id stk3310_i2c_id[] = {
675 	{"STK3310", 0},
676 	{"STK3311", 0},
677 	{}
678 };
679 
680 static const struct acpi_device_id stk3310_acpi_id[] = {
681 	{"STK3310", 0},
682 	{"STK3311", 0},
683 	{}
684 };
685 
686 MODULE_DEVICE_TABLE(acpi, stk3310_acpi_id);
687 
688 static struct i2c_driver stk3310_driver = {
689 	.driver = {
690 		.name = "stk3310",
691 		.pm = STK3310_PM_OPS,
692 		.acpi_match_table = ACPI_PTR(stk3310_acpi_id),
693 	},
694 	.probe =            stk3310_probe,
695 	.remove =           stk3310_remove,
696 	.id_table =         stk3310_i2c_id,
697 };
698 
699 module_i2c_driver(stk3310_driver);
700 
701 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
702 MODULE_DESCRIPTION("STK3310 Ambient Light and Proximity Sensor driver");
703 MODULE_LICENSE("GPL v2");
704