1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
4  *
5  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
6  * Copyright (c) 2015 Essensium NV
7  * Copyright (c) 2015 Melexis
8  *
9  * Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
10  *
11  * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
12  *
13  * To wake up from sleep mode, the SDA line must be held low while SCL is high
14  * for at least 33ms.  This is achieved with an extra GPIO that can be connected
15  * directly to the SDA line.  In normal operation, the GPIO is set as input and
16  * will not interfere in I2C communication.  While the GPIO is driven low, the
17  * i2c adapter is locked since it cannot be used by other clients.  The SCL line
18  * always has a pull-up so we do not need an extra GPIO to drive it high.  If
19  * the "wakeup" GPIO is not given, power management will be disabled.
20  */
21 
22 #include <linux/err.h>
23 #include <linux/i2c.h>
24 #include <linux/module.h>
25 #include <linux/delay.h>
26 #include <linux/jiffies.h>
27 #include <linux/gpio/consumer.h>
28 #include <linux/pm_runtime.h>
29 
30 #include <linux/iio/iio.h>
31 #include <linux/iio/sysfs.h>
32 
33 #define MLX90614_OP_RAM		0x00
34 #define MLX90614_OP_EEPROM	0x20
35 #define MLX90614_OP_SLEEP	0xff
36 
37 /* RAM offsets with 16-bit data, MSB first */
38 #define MLX90614_RAW1	(MLX90614_OP_RAM | 0x04) /* raw data IR channel 1 */
39 #define MLX90614_RAW2	(MLX90614_OP_RAM | 0x05) /* raw data IR channel 2 */
40 #define MLX90614_TA	(MLX90614_OP_RAM | 0x06) /* ambient temperature */
41 #define MLX90614_TOBJ1	(MLX90614_OP_RAM | 0x07) /* object 1 temperature */
42 #define MLX90614_TOBJ2	(MLX90614_OP_RAM | 0x08) /* object 2 temperature */
43 
44 /* EEPROM offsets with 16-bit data, MSB first */
45 #define MLX90614_EMISSIVITY	(MLX90614_OP_EEPROM | 0x04) /* emissivity correction coefficient */
46 #define MLX90614_CONFIG		(MLX90614_OP_EEPROM | 0x05) /* configuration register */
47 
48 /* Control bits in configuration register */
49 #define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
50 #define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
51 #define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
52 #define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
53 #define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
54 #define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
55 #define MLX90614_CONFIG_GAIN_SHIFT 11 /* gain */
56 #define MLX90614_CONFIG_GAIN_MASK (0x7 << MLX90614_CONFIG_GAIN_SHIFT)
57 
58 /* Timings (in ms) */
59 #define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
60 #define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
61 #define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
62 
63 #define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
64 
65 /* Magic constants */
66 #define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
67 #define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.15*50) */
68 #define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
69 #define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
70 #define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */
71 #define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
72 
73 struct mlx90614_data {
74 	struct i2c_client *client;
75 	struct mutex lock; /* for EEPROM access only */
76 	struct gpio_desc *wakeup_gpio; /* NULL to disable sleep/wake-up */
77 	unsigned long ready_timestamp; /* in jiffies */
78 };
79 
80 /* Bandwidth values for IIR filtering */
81 static const int mlx90614_iir_values[] = {77, 31, 20, 15, 723, 153, 110, 86};
82 static const int mlx90614_freqs[][2] = {
83 	{0, 150000},
84 	{0, 200000},
85 	{0, 310000},
86 	{0, 770000},
87 	{0, 860000},
88 	{1, 100000},
89 	{1, 530000},
90 	{7, 230000}
91 };
92 
93 /*
94  * Erase an address and write word.
95  * The mutex must be locked before calling.
96  */
97 static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
98 			       u16 value)
99 {
100 	/*
101 	 * Note: The mlx90614 requires a PEC on writing but does not send us a
102 	 * valid PEC on reading.  Hence, we cannot set I2C_CLIENT_PEC in
103 	 * i2c_client.flags.  As a workaround, we use i2c_smbus_xfer here.
104 	 */
105 	union i2c_smbus_data data;
106 	s32 ret;
107 
108 	dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
109 
110 	data.word = 0x0000; /* erase command */
111 	ret = i2c_smbus_xfer(client->adapter, client->addr,
112 			     client->flags | I2C_CLIENT_PEC,
113 			     I2C_SMBUS_WRITE, command,
114 			     I2C_SMBUS_WORD_DATA, &data);
115 	if (ret < 0)
116 		return ret;
117 
118 	msleep(MLX90614_TIMING_EEPROM);
119 
120 	data.word = value; /* actual write */
121 	ret = i2c_smbus_xfer(client->adapter, client->addr,
122 			     client->flags | I2C_CLIENT_PEC,
123 			     I2C_SMBUS_WRITE, command,
124 			     I2C_SMBUS_WORD_DATA, &data);
125 
126 	msleep(MLX90614_TIMING_EEPROM);
127 
128 	return ret;
129 }
130 
131 /*
132  * Find the IIR value inside mlx90614_iir_values array and return its position
133  * which is equivalent to the bit value in sensor register
134  */
135 static inline s32 mlx90614_iir_search(const struct i2c_client *client,
136 				      int value)
137 {
138 	int i;
139 	s32 ret;
140 
141 	for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
142 		if (value == mlx90614_iir_values[i])
143 			break;
144 	}
145 
146 	if (i == ARRAY_SIZE(mlx90614_iir_values))
147 		return -EINVAL;
148 
149 	/*
150 	 * CONFIG register values must not be changed so
151 	 * we must read them before we actually write
152 	 * changes
153 	 */
154 	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
155 	if (ret < 0)
156 		return ret;
157 
158 	ret &= ~MLX90614_CONFIG_FIR_MASK;
159 	ret |= MLX90614_CONST_FIR << MLX90614_CONFIG_FIR_SHIFT;
160 	ret &= ~MLX90614_CONFIG_IIR_MASK;
161 	ret |= i << MLX90614_CONFIG_IIR_SHIFT;
162 
163 	/* Write changed values */
164 	ret = mlx90614_write_word(client, MLX90614_CONFIG, ret);
165 	return ret;
166 }
167 
168 #ifdef CONFIG_PM
169 /*
170  * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
171  * the last wake-up.  This is normally only needed to get a valid temperature
172  * reading.  EEPROM access does not need such delay.
173  * Return 0 on success, <0 on error.
174  */
175 static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
176 {
177 	unsigned long now;
178 	int ret;
179 
180 	if (!data->wakeup_gpio)
181 		return 0;
182 
183 	ret = pm_runtime_resume_and_get(&data->client->dev);
184 	if (ret < 0)
185 		return ret;
186 
187 	if (startup) {
188 		now = jiffies;
189 		if (time_before(now, data->ready_timestamp) &&
190 		    msleep_interruptible(jiffies_to_msecs(
191 				data->ready_timestamp - now)) != 0) {
192 			pm_runtime_put_autosuspend(&data->client->dev);
193 			return -EINTR;
194 		}
195 	}
196 
197 	return 0;
198 }
199 
200 static void mlx90614_power_put(struct mlx90614_data *data)
201 {
202 	if (!data->wakeup_gpio)
203 		return;
204 
205 	pm_runtime_mark_last_busy(&data->client->dev);
206 	pm_runtime_put_autosuspend(&data->client->dev);
207 }
208 #else
209 static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
210 {
211 	return 0;
212 }
213 
214 static inline void mlx90614_power_put(struct mlx90614_data *data)
215 {
216 }
217 #endif
218 
219 static int mlx90614_read_raw(struct iio_dev *indio_dev,
220 			    struct iio_chan_spec const *channel, int *val,
221 			    int *val2, long mask)
222 {
223 	struct mlx90614_data *data = iio_priv(indio_dev);
224 	u8 cmd;
225 	s32 ret;
226 
227 	switch (mask) {
228 	case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
229 		switch (channel->channel2) {
230 		case IIO_MOD_TEMP_AMBIENT:
231 			cmd = MLX90614_TA;
232 			break;
233 		case IIO_MOD_TEMP_OBJECT:
234 			switch (channel->channel) {
235 			case 0:
236 				cmd = MLX90614_TOBJ1;
237 				break;
238 			case 1:
239 				cmd = MLX90614_TOBJ2;
240 				break;
241 			default:
242 				return -EINVAL;
243 			}
244 			break;
245 		default:
246 			return -EINVAL;
247 		}
248 
249 		ret = mlx90614_power_get(data, true);
250 		if (ret < 0)
251 			return ret;
252 		ret = i2c_smbus_read_word_data(data->client, cmd);
253 		mlx90614_power_put(data);
254 
255 		if (ret < 0)
256 			return ret;
257 
258 		/* MSB is an error flag */
259 		if (ret & 0x8000)
260 			return -EIO;
261 
262 		*val = ret;
263 		return IIO_VAL_INT;
264 	case IIO_CHAN_INFO_OFFSET:
265 		*val = MLX90614_CONST_OFFSET_DEC;
266 		*val2 = MLX90614_CONST_OFFSET_REM;
267 		return IIO_VAL_INT_PLUS_MICRO;
268 	case IIO_CHAN_INFO_SCALE:
269 		*val = MLX90614_CONST_SCALE;
270 		return IIO_VAL_INT;
271 	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
272 		ret = mlx90614_power_get(data, false);
273 		if (ret < 0)
274 			return ret;
275 
276 		mutex_lock(&data->lock);
277 		ret = i2c_smbus_read_word_data(data->client,
278 					       MLX90614_EMISSIVITY);
279 		mutex_unlock(&data->lock);
280 		mlx90614_power_put(data);
281 
282 		if (ret < 0)
283 			return ret;
284 
285 		if (ret == MLX90614_CONST_RAW_EMISSIVITY_MAX) {
286 			*val = 1;
287 			*val2 = 0;
288 		} else {
289 			*val = 0;
290 			*val2 = ret * MLX90614_CONST_EMISSIVITY_RESOLUTION;
291 		}
292 		return IIO_VAL_INT_PLUS_NANO;
293 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
294 							     FIR = 1024 */
295 		ret = mlx90614_power_get(data, false);
296 		if (ret < 0)
297 			return ret;
298 
299 		mutex_lock(&data->lock);
300 		ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
301 		mutex_unlock(&data->lock);
302 		mlx90614_power_put(data);
303 
304 		if (ret < 0)
305 			return ret;
306 
307 		*val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
308 		*val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100) *
309 			10000;
310 		return IIO_VAL_INT_PLUS_MICRO;
311 	default:
312 		return -EINVAL;
313 	}
314 }
315 
316 static int mlx90614_write_raw(struct iio_dev *indio_dev,
317 			     struct iio_chan_spec const *channel, int val,
318 			     int val2, long mask)
319 {
320 	struct mlx90614_data *data = iio_priv(indio_dev);
321 	s32 ret;
322 
323 	switch (mask) {
324 	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
325 		if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
326 			return -EINVAL;
327 		val = val * MLX90614_CONST_RAW_EMISSIVITY_MAX +
328 			val2 / MLX90614_CONST_EMISSIVITY_RESOLUTION;
329 
330 		ret = mlx90614_power_get(data, false);
331 		if (ret < 0)
332 			return ret;
333 
334 		mutex_lock(&data->lock);
335 		ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,
336 					  val);
337 		mutex_unlock(&data->lock);
338 		mlx90614_power_put(data);
339 
340 		return ret;
341 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
342 		if (val < 0 || val2 < 0)
343 			return -EINVAL;
344 
345 		ret = mlx90614_power_get(data, false);
346 		if (ret < 0)
347 			return ret;
348 
349 		mutex_lock(&data->lock);
350 		ret = mlx90614_iir_search(data->client,
351 					  val * 100 + val2 / 10000);
352 		mutex_unlock(&data->lock);
353 		mlx90614_power_put(data);
354 
355 		return ret;
356 	default:
357 		return -EINVAL;
358 	}
359 }
360 
361 static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
362 				     struct iio_chan_spec const *channel,
363 				     long mask)
364 {
365 	switch (mask) {
366 	case IIO_CHAN_INFO_CALIBEMISSIVITY:
367 		return IIO_VAL_INT_PLUS_NANO;
368 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
369 		return IIO_VAL_INT_PLUS_MICRO;
370 	default:
371 		return -EINVAL;
372 	}
373 }
374 
375 static int mlx90614_read_avail(struct iio_dev *indio_dev,
376 			       struct iio_chan_spec const *chan,
377 			       const int **vals, int *type, int *length,
378 			       long mask)
379 {
380 	switch (mask) {
381 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
382 		*vals = (int *)mlx90614_freqs;
383 		*type = IIO_VAL_INT_PLUS_MICRO;
384 		*length = 2 * ARRAY_SIZE(mlx90614_freqs);
385 		return IIO_AVAIL_LIST;
386 	default:
387 		return -EINVAL;
388 	}
389 }
390 
391 static const struct iio_chan_spec mlx90614_channels[] = {
392 	{
393 		.type = IIO_TEMP,
394 		.modified = 1,
395 		.channel2 = IIO_MOD_TEMP_AMBIENT,
396 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
397 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
398 		    BIT(IIO_CHAN_INFO_SCALE),
399 	},
400 	{
401 		.type = IIO_TEMP,
402 		.modified = 1,
403 		.channel2 = IIO_MOD_TEMP_OBJECT,
404 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
405 		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
406 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
407 		.info_mask_separate_available =
408 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
409 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
410 		    BIT(IIO_CHAN_INFO_SCALE),
411 	},
412 	{
413 		.type = IIO_TEMP,
414 		.indexed = 1,
415 		.modified = 1,
416 		.channel = 1,
417 		.channel2 = IIO_MOD_TEMP_OBJECT,
418 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
419 		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
420 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
421 		.info_mask_separate_available =
422 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
423 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
424 		    BIT(IIO_CHAN_INFO_SCALE),
425 	},
426 };
427 
428 static const struct iio_info mlx90614_info = {
429 	.read_raw = mlx90614_read_raw,
430 	.write_raw = mlx90614_write_raw,
431 	.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
432 	.read_avail = mlx90614_read_avail,
433 };
434 
435 #ifdef CONFIG_PM
436 static int mlx90614_sleep(struct mlx90614_data *data)
437 {
438 	s32 ret;
439 
440 	if (!data->wakeup_gpio) {
441 		dev_dbg(&data->client->dev, "Sleep disabled");
442 		return -ENOSYS;
443 	}
444 
445 	dev_dbg(&data->client->dev, "Requesting sleep");
446 
447 	mutex_lock(&data->lock);
448 	ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
449 			     data->client->flags | I2C_CLIENT_PEC,
450 			     I2C_SMBUS_WRITE, MLX90614_OP_SLEEP,
451 			     I2C_SMBUS_BYTE, NULL);
452 	mutex_unlock(&data->lock);
453 
454 	return ret;
455 }
456 
457 static int mlx90614_wakeup(struct mlx90614_data *data)
458 {
459 	if (!data->wakeup_gpio) {
460 		dev_dbg(&data->client->dev, "Wake-up disabled");
461 		return -ENOSYS;
462 	}
463 
464 	dev_dbg(&data->client->dev, "Requesting wake-up");
465 
466 	i2c_lock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
467 	gpiod_direction_output(data->wakeup_gpio, 0);
468 	msleep(MLX90614_TIMING_WAKEUP);
469 	gpiod_direction_input(data->wakeup_gpio);
470 	i2c_unlock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
471 
472 	data->ready_timestamp = jiffies +
473 			msecs_to_jiffies(MLX90614_TIMING_STARTUP);
474 
475 	/*
476 	 * Quirk: the i2c controller may get confused right after the
477 	 * wake-up signal has been sent.  As a workaround, do a dummy read.
478 	 * If the read fails, the controller will probably be reset so that
479 	 * further reads will work.
480 	 */
481 	i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
482 
483 	return 0;
484 }
485 
486 /* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
487 static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
488 {
489 	struct gpio_desc *gpio;
490 
491 	if (!i2c_check_functionality(client->adapter,
492 						I2C_FUNC_SMBUS_WRITE_BYTE)) {
493 		dev_info(&client->dev,
494 			 "i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
495 		return NULL;
496 	}
497 
498 	gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
499 
500 	if (IS_ERR(gpio)) {
501 		dev_warn(&client->dev,
502 			 "gpio acquisition failed with error %ld, sleep disabled",
503 			 PTR_ERR(gpio));
504 		return NULL;
505 	} else if (!gpio) {
506 		dev_info(&client->dev,
507 			 "wakeup-gpio not found, sleep disabled");
508 	}
509 
510 	return gpio;
511 }
512 #else
513 static inline int mlx90614_sleep(struct mlx90614_data *data)
514 {
515 	return -ENOSYS;
516 }
517 static inline int mlx90614_wakeup(struct mlx90614_data *data)
518 {
519 	return -ENOSYS;
520 }
521 static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
522 {
523 	return NULL;
524 }
525 #endif
526 
527 /* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
528 static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
529 {
530 	s32 ret;
531 
532 	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
533 
534 	if (ret < 0)
535 		return ret;
536 
537 	return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
538 }
539 
540 static int mlx90614_probe(struct i2c_client *client)
541 {
542 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
543 	struct iio_dev *indio_dev;
544 	struct mlx90614_data *data;
545 	int ret;
546 
547 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
548 		return -EOPNOTSUPP;
549 
550 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
551 	if (!indio_dev)
552 		return -ENOMEM;
553 
554 	data = iio_priv(indio_dev);
555 	i2c_set_clientdata(client, indio_dev);
556 	data->client = client;
557 	mutex_init(&data->lock);
558 	data->wakeup_gpio = mlx90614_probe_wakeup(client);
559 
560 	mlx90614_wakeup(data);
561 
562 	indio_dev->name = id->name;
563 	indio_dev->modes = INDIO_DIRECT_MODE;
564 	indio_dev->info = &mlx90614_info;
565 
566 	ret = mlx90614_probe_num_ir_sensors(client);
567 	switch (ret) {
568 	case 0:
569 		dev_dbg(&client->dev, "Found single sensor");
570 		indio_dev->channels = mlx90614_channels;
571 		indio_dev->num_channels = 2;
572 		break;
573 	case 1:
574 		dev_dbg(&client->dev, "Found dual sensor");
575 		indio_dev->channels = mlx90614_channels;
576 		indio_dev->num_channels = 3;
577 		break;
578 	default:
579 		return ret;
580 	}
581 
582 	if (data->wakeup_gpio) {
583 		pm_runtime_set_autosuspend_delay(&client->dev,
584 						 MLX90614_AUTOSLEEP_DELAY);
585 		pm_runtime_use_autosuspend(&client->dev);
586 		pm_runtime_set_active(&client->dev);
587 		pm_runtime_enable(&client->dev);
588 	}
589 
590 	return iio_device_register(indio_dev);
591 }
592 
593 static void mlx90614_remove(struct i2c_client *client)
594 {
595 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
596 	struct mlx90614_data *data = iio_priv(indio_dev);
597 
598 	iio_device_unregister(indio_dev);
599 
600 	if (data->wakeup_gpio) {
601 		pm_runtime_disable(&client->dev);
602 		if (!pm_runtime_status_suspended(&client->dev))
603 			mlx90614_sleep(data);
604 		pm_runtime_set_suspended(&client->dev);
605 	}
606 }
607 
608 static const struct i2c_device_id mlx90614_id[] = {
609 	{ "mlx90614", 0 },
610 	{ }
611 };
612 MODULE_DEVICE_TABLE(i2c, mlx90614_id);
613 
614 static const struct of_device_id mlx90614_of_match[] = {
615 	{ .compatible = "melexis,mlx90614" },
616 	{ }
617 };
618 MODULE_DEVICE_TABLE(of, mlx90614_of_match);
619 
620 static int mlx90614_pm_suspend(struct device *dev)
621 {
622 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
623 	struct mlx90614_data *data = iio_priv(indio_dev);
624 
625 	if (data->wakeup_gpio && pm_runtime_active(dev))
626 		return mlx90614_sleep(data);
627 
628 	return 0;
629 }
630 
631 static int mlx90614_pm_resume(struct device *dev)
632 {
633 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
634 	struct mlx90614_data *data = iio_priv(indio_dev);
635 	int err;
636 
637 	if (data->wakeup_gpio) {
638 		err = mlx90614_wakeup(data);
639 		if (err < 0)
640 			return err;
641 
642 		pm_runtime_disable(dev);
643 		pm_runtime_set_active(dev);
644 		pm_runtime_enable(dev);
645 	}
646 
647 	return 0;
648 }
649 
650 static int mlx90614_pm_runtime_suspend(struct device *dev)
651 {
652 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
653 	struct mlx90614_data *data = iio_priv(indio_dev);
654 
655 	return mlx90614_sleep(data);
656 }
657 
658 static int mlx90614_pm_runtime_resume(struct device *dev)
659 {
660 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
661 	struct mlx90614_data *data = iio_priv(indio_dev);
662 
663 	return mlx90614_wakeup(data);
664 }
665 
666 static const struct dev_pm_ops mlx90614_pm_ops = {
667 	SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
668 	RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
669 		       mlx90614_pm_runtime_resume, NULL)
670 };
671 
672 static struct i2c_driver mlx90614_driver = {
673 	.driver = {
674 		.name	= "mlx90614",
675 		.of_match_table = mlx90614_of_match,
676 		.pm	= pm_ptr(&mlx90614_pm_ops),
677 	},
678 	.probe_new = mlx90614_probe,
679 	.remove = mlx90614_remove,
680 	.id_table = mlx90614_id,
681 };
682 module_i2c_driver(mlx90614_driver);
683 
684 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
685 MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
686 MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
687 MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
688 MODULE_LICENSE("GPL");
689