xref: /linux/drivers/iio/temperature/mlx90614.c (revision f468cf53c5240bf5063d0c6fe620b5ae2de37801)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mlx90614.c - Support for Melexis MLX90614/MLX90615 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/MLX90615 I2C 16-bit IR thermopile sensor
10  *
11  * MLX90614 - 17-bit ADC + MLX90302 DSP
12  * MLX90615 - 16-bit ADC + MLX90325 DSP
13  *
14  * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
15  *
16  * To wake up from sleep mode, the SDA line must be held low while SCL is high
17  * for at least 33ms.  This is achieved with an extra GPIO that can be connected
18  * directly to the SDA line.  In normal operation, the GPIO is set as input and
19  * will not interfere in I2C communication.  While the GPIO is driven low, the
20  * i2c adapter is locked since it cannot be used by other clients.  The SCL line
21  * always has a pull-up so we do not need an extra GPIO to drive it high.  If
22  * the "wakeup" GPIO is not given, power management will be disabled.
23  */
24 
25 #include <linux/bitfield.h>
26 #include <linux/delay.h>
27 #include <linux/err.h>
28 #include <linux/gpio/consumer.h>
29 #include <linux/i2c.h>
30 #include <linux/jiffies.h>
31 #include <linux/mod_devicetable.h>
32 #include <linux/module.h>
33 #include <linux/pm_runtime.h>
34 
35 #include <linux/iio/iio.h>
36 #include <linux/iio/sysfs.h>
37 
38 #define MLX90614_OP_RAM		0x00
39 #define MLX90614_OP_EEPROM	0x20
40 #define MLX90614_OP_SLEEP	0xff
41 
42 #define MLX90615_OP_EEPROM	0x10
43 #define MLX90615_OP_RAM		0x20
44 #define MLX90615_OP_SLEEP	0xc6
45 
46 /* Control bits in configuration register */
47 #define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
48 #define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
49 #define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
50 #define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
51 #define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
52 #define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
53 
54 #define MLX90615_CONFIG_IIR_SHIFT 12 /* IIR coefficient */
55 #define MLX90615_CONFIG_IIR_MASK (0x7 << MLX90615_CONFIG_IIR_SHIFT)
56 
57 /* Timings (in ms) */
58 #define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
59 #define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
60 #define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
61 
62 #define MLX90615_TIMING_WAKEUP 22 /* time to hold SCL low for wake-up */
63 
64 #define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
65 
66 /* Magic constants */
67 #define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
68 #define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.15*50) */
69 #define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
70 #define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
71 
72 struct mlx_chip_info {
73 	/* EEPROM offsets with 16-bit data, MSB first */
74 	/* emissivity correction coefficient */
75 	u8			op_eeprom_emissivity;
76 	u8			op_eeprom_config1;
77 	/* RAM offsets with 16-bit data, MSB first */
78 	/* ambient temperature */
79 	u8			op_ram_ta;
80 	/* object 1 temperature */
81 	u8			op_ram_tobj1;
82 	/* object 2 temperature */
83 	u8			op_ram_tobj2;
84 	u8			op_sleep;
85 	/* support for two input channels (MLX90614 only) */
86 	u8			dual_channel;
87 	u8			wakeup_delay_ms;
88 	u16			emissivity_max;
89 	u16			fir_config_mask;
90 	u16			iir_config_mask;
91 	int			iir_valid_offset;
92 	u16			iir_values[8];
93 	int			iir_freqs[8][2];
94 };
95 
96 struct mlx90614_data {
97 	struct i2c_client *client;
98 	struct mutex lock; /* for EEPROM access only */
99 	struct gpio_desc *wakeup_gpio; /* NULL to disable sleep/wake-up */
100 	const struct mlx_chip_info *chip_info; /* Chip hardware details */
101 	unsigned long ready_timestamp; /* in jiffies */
102 };
103 
104 /*
105  * Erase an address and write word.
106  * The mutex must be locked before calling.
107  */
mlx90614_write_word(const struct i2c_client * client,u8 command,u16 value)108 static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
109 			       u16 value)
110 {
111 	/*
112 	 * Note: The mlx90614 requires a PEC on writing but does not send us a
113 	 * valid PEC on reading.  Hence, we cannot set I2C_CLIENT_PEC in
114 	 * i2c_client.flags.  As a workaround, we use i2c_smbus_xfer here.
115 	 */
116 	union i2c_smbus_data data;
117 	s32 ret;
118 
119 	dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
120 
121 	data.word = 0x0000; /* erase command */
122 	ret = i2c_smbus_xfer(client->adapter, client->addr,
123 			     client->flags | I2C_CLIENT_PEC,
124 			     I2C_SMBUS_WRITE, command,
125 			     I2C_SMBUS_WORD_DATA, &data);
126 	if (ret < 0)
127 		return ret;
128 
129 	msleep(MLX90614_TIMING_EEPROM);
130 
131 	data.word = value; /* actual write */
132 	ret = i2c_smbus_xfer(client->adapter, client->addr,
133 			     client->flags | I2C_CLIENT_PEC,
134 			     I2C_SMBUS_WRITE, command,
135 			     I2C_SMBUS_WORD_DATA, &data);
136 
137 	msleep(MLX90614_TIMING_EEPROM);
138 
139 	return ret;
140 }
141 
142 /*
143  * Find the IIR value inside iir_values array and return its position
144  * which is equivalent to the bit value in sensor register
145  */
mlx90614_iir_search(const struct i2c_client * client,int value)146 static inline s32 mlx90614_iir_search(const struct i2c_client *client,
147 				      int value)
148 {
149 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
150 	struct mlx90614_data *data = iio_priv(indio_dev);
151 	const struct mlx_chip_info *chip_info = data->chip_info;
152 	int i;
153 	s32 ret;
154 
155 	for (i = chip_info->iir_valid_offset;
156 	     i < ARRAY_SIZE(chip_info->iir_values);
157 	     i++) {
158 		if (value == chip_info->iir_values[i])
159 			break;
160 	}
161 
162 	if (i == ARRAY_SIZE(chip_info->iir_values))
163 		return -EINVAL;
164 
165 	/*
166 	 * CONFIG register values must not be changed so
167 	 * we must read them before we actually write
168 	 * changes
169 	 */
170 	ret = i2c_smbus_read_word_data(client, chip_info->op_eeprom_config1);
171 	if (ret < 0)
172 		return ret;
173 
174 	/* Modify FIR on parts which have configurable FIR filter */
175 	if (chip_info->fir_config_mask) {
176 		ret &= ~chip_info->fir_config_mask;
177 		ret |= field_prep(chip_info->fir_config_mask, MLX90614_CONST_FIR);
178 	}
179 
180 	ret &= ~chip_info->iir_config_mask;
181 	ret |= field_prep(chip_info->iir_config_mask, i);
182 
183 	/* Write changed values */
184 	ret = mlx90614_write_word(client, chip_info->op_eeprom_config1, ret);
185 	return ret;
186 }
187 
188 #ifdef CONFIG_PM
189 /*
190  * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
191  * the last wake-up.  This is normally only needed to get a valid temperature
192  * reading.  EEPROM access does not need such delay.
193  * Return 0 on success, <0 on error.
194  */
mlx90614_power_get(struct mlx90614_data * data,bool startup)195 static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
196 {
197 	unsigned long now;
198 	int ret;
199 
200 	if (!data->wakeup_gpio)
201 		return 0;
202 
203 	ret = pm_runtime_resume_and_get(&data->client->dev);
204 	if (ret < 0)
205 		return ret;
206 
207 	if (startup) {
208 		now = jiffies;
209 		if (time_before(now, data->ready_timestamp) &&
210 		    msleep_interruptible(jiffies_to_msecs(
211 				data->ready_timestamp - now)) != 0) {
212 			pm_runtime_put_autosuspend(&data->client->dev);
213 			return -EINTR;
214 		}
215 	}
216 
217 	return 0;
218 }
219 
mlx90614_power_put(struct mlx90614_data * data)220 static void mlx90614_power_put(struct mlx90614_data *data)
221 {
222 	if (!data->wakeup_gpio)
223 		return;
224 
225 	pm_runtime_put_autosuspend(&data->client->dev);
226 }
227 #else
mlx90614_power_get(struct mlx90614_data * data,bool startup)228 static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
229 {
230 	return 0;
231 }
232 
mlx90614_power_put(struct mlx90614_data * data)233 static inline void mlx90614_power_put(struct mlx90614_data *data)
234 {
235 }
236 #endif
237 
mlx90614_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int * val,int * val2,long mask)238 static int mlx90614_read_raw(struct iio_dev *indio_dev,
239 			    struct iio_chan_spec const *channel, int *val,
240 			    int *val2, long mask)
241 {
242 	struct mlx90614_data *data = iio_priv(indio_dev);
243 	const struct mlx_chip_info *chip_info = data->chip_info;
244 	u8 cmd, idx;
245 	s32 ret;
246 
247 	switch (mask) {
248 	case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
249 		switch (channel->channel2) {
250 		case IIO_MOD_TEMP_AMBIENT:
251 			cmd = chip_info->op_ram_ta;
252 			break;
253 		case IIO_MOD_TEMP_OBJECT:
254 			if (chip_info->dual_channel && channel->channel)
255 				return -EINVAL;
256 
257 			switch (channel->channel) {
258 			case 0:
259 				cmd = chip_info->op_ram_tobj1;
260 				break;
261 			case 1:
262 				cmd = chip_info->op_ram_tobj2;
263 				break;
264 			default:
265 				return -EINVAL;
266 			}
267 			break;
268 		default:
269 			return -EINVAL;
270 		}
271 
272 		ret = mlx90614_power_get(data, true);
273 		if (ret < 0)
274 			return ret;
275 		ret = i2c_smbus_read_word_data(data->client, cmd);
276 		mlx90614_power_put(data);
277 
278 		if (ret < 0)
279 			return ret;
280 
281 		/* MSB is an error flag */
282 		if (ret & 0x8000)
283 			return -EIO;
284 
285 		*val = ret;
286 		return IIO_VAL_INT;
287 	case IIO_CHAN_INFO_OFFSET:
288 		*val = MLX90614_CONST_OFFSET_DEC;
289 		*val2 = MLX90614_CONST_OFFSET_REM;
290 		return IIO_VAL_INT_PLUS_MICRO;
291 	case IIO_CHAN_INFO_SCALE:
292 		*val = MLX90614_CONST_SCALE;
293 		return IIO_VAL_INT;
294 	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/emissivity_max / LSB */
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,
301 					       chip_info->op_eeprom_emissivity);
302 		mutex_unlock(&data->lock);
303 		mlx90614_power_put(data);
304 
305 		if (ret < 0)
306 			return ret;
307 
308 		if (ret == chip_info->emissivity_max) {
309 			*val = 1;
310 			*val2 = 0;
311 		} else {
312 			*val = 0;
313 			*val2 = ret * NSEC_PER_SEC / chip_info->emissivity_max;
314 		}
315 		return IIO_VAL_INT_PLUS_NANO;
316 	/* IIR setting with FIR=1024 (MLX90614) or FIR=65536 (MLX90615) */
317 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
318 		ret = mlx90614_power_get(data, false);
319 		if (ret < 0)
320 			return ret;
321 
322 		mutex_lock(&data->lock);
323 		ret = i2c_smbus_read_word_data(data->client,
324 					       chip_info->op_eeprom_config1);
325 		mutex_unlock(&data->lock);
326 		mlx90614_power_put(data);
327 
328 		if (ret < 0)
329 			return ret;
330 
331 		idx = field_get(chip_info->iir_config_mask, ret) -
332 		      chip_info->iir_valid_offset;
333 
334 		*val = chip_info->iir_values[idx] / 100;
335 		*val2 = (chip_info->iir_values[idx] % 100) * 10000;
336 		return IIO_VAL_INT_PLUS_MICRO;
337 	default:
338 		return -EINVAL;
339 	}
340 }
341 
mlx90614_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int val,int val2,long mask)342 static int mlx90614_write_raw(struct iio_dev *indio_dev,
343 			     struct iio_chan_spec const *channel, int val,
344 			     int val2, long mask)
345 {
346 	struct mlx90614_data *data = iio_priv(indio_dev);
347 	const struct mlx_chip_info *chip_info = data->chip_info;
348 	s32 ret;
349 
350 	switch (mask) {
351 	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/emissivity_max / LSB */
352 		if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
353 			return -EINVAL;
354 		val = val * chip_info->emissivity_max +
355 		      val2 * chip_info->emissivity_max / NSEC_PER_SEC;
356 
357 		ret = mlx90614_power_get(data, false);
358 		if (ret < 0)
359 			return ret;
360 
361 		mutex_lock(&data->lock);
362 		ret = mlx90614_write_word(data->client,
363 					  chip_info->op_eeprom_emissivity, val);
364 		mutex_unlock(&data->lock);
365 		mlx90614_power_put(data);
366 
367 		return ret;
368 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
369 		if (val < 0 || val2 < 0)
370 			return -EINVAL;
371 
372 		ret = mlx90614_power_get(data, false);
373 		if (ret < 0)
374 			return ret;
375 
376 		mutex_lock(&data->lock);
377 		ret = mlx90614_iir_search(data->client,
378 					  val * 100 + val2 / 10000);
379 		mutex_unlock(&data->lock);
380 		mlx90614_power_put(data);
381 
382 		return ret;
383 	default:
384 		return -EINVAL;
385 	}
386 }
387 
mlx90614_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,long mask)388 static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
389 				     struct iio_chan_spec const *channel,
390 				     long mask)
391 {
392 	switch (mask) {
393 	case IIO_CHAN_INFO_CALIBEMISSIVITY:
394 		return IIO_VAL_INT_PLUS_NANO;
395 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
396 		return IIO_VAL_INT_PLUS_MICRO;
397 	default:
398 		return -EINVAL;
399 	}
400 }
401 
mlx90614_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)402 static int mlx90614_read_avail(struct iio_dev *indio_dev,
403 			       struct iio_chan_spec const *chan,
404 			       const int **vals, int *type, int *length,
405 			       long mask)
406 {
407 	struct mlx90614_data *data = iio_priv(indio_dev);
408 	const struct mlx_chip_info *chip_info = data->chip_info;
409 
410 	switch (mask) {
411 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
412 		*vals = (int *)chip_info->iir_freqs;
413 		*type = IIO_VAL_INT_PLUS_MICRO;
414 		*length = 2 * (ARRAY_SIZE(chip_info->iir_freqs) -
415 			       chip_info->iir_valid_offset);
416 		return IIO_AVAIL_LIST;
417 	default:
418 		return -EINVAL;
419 	}
420 }
421 
422 static const struct iio_chan_spec mlx90614_channels[] = {
423 	{
424 		.type = IIO_TEMP,
425 		.modified = 1,
426 		.channel2 = IIO_MOD_TEMP_AMBIENT,
427 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
428 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
429 		    BIT(IIO_CHAN_INFO_SCALE),
430 	},
431 	{
432 		.type = IIO_TEMP,
433 		.modified = 1,
434 		.channel2 = IIO_MOD_TEMP_OBJECT,
435 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
436 		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
437 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
438 		.info_mask_separate_available =
439 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
440 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
441 		    BIT(IIO_CHAN_INFO_SCALE),
442 	},
443 	{
444 		.type = IIO_TEMP,
445 		.indexed = 1,
446 		.modified = 1,
447 		.channel = 1,
448 		.channel2 = IIO_MOD_TEMP_OBJECT,
449 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
450 		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
451 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
452 		.info_mask_separate_available =
453 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
454 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
455 		    BIT(IIO_CHAN_INFO_SCALE),
456 	},
457 };
458 
459 static const struct iio_info mlx90614_info = {
460 	.read_raw = mlx90614_read_raw,
461 	.write_raw = mlx90614_write_raw,
462 	.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
463 	.read_avail = mlx90614_read_avail,
464 };
465 
466 #ifdef CONFIG_PM
mlx90614_sleep(struct mlx90614_data * data)467 static int mlx90614_sleep(struct mlx90614_data *data)
468 {
469 	const struct mlx_chip_info *chip_info = data->chip_info;
470 	s32 ret;
471 
472 	if (!data->wakeup_gpio) {
473 		dev_dbg(&data->client->dev, "Sleep disabled");
474 		return -ENOSYS;
475 	}
476 
477 	dev_dbg(&data->client->dev, "Requesting sleep");
478 
479 	mutex_lock(&data->lock);
480 	ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
481 			     data->client->flags | I2C_CLIENT_PEC,
482 			     I2C_SMBUS_WRITE, chip_info->op_sleep,
483 			     I2C_SMBUS_BYTE, NULL);
484 	mutex_unlock(&data->lock);
485 
486 	return ret;
487 }
488 
mlx90614_wakeup(struct mlx90614_data * data)489 static int mlx90614_wakeup(struct mlx90614_data *data)
490 {
491 	const struct mlx_chip_info *chip_info = data->chip_info;
492 
493 	if (!data->wakeup_gpio) {
494 		dev_dbg(&data->client->dev, "Wake-up disabled");
495 		return -ENOSYS;
496 	}
497 
498 	dev_dbg(&data->client->dev, "Requesting wake-up");
499 
500 	i2c_lock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
501 	gpiod_direction_output(data->wakeup_gpio, 0);
502 	msleep(chip_info->wakeup_delay_ms);
503 	gpiod_direction_input(data->wakeup_gpio);
504 	i2c_unlock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
505 
506 	data->ready_timestamp = jiffies +
507 			msecs_to_jiffies(MLX90614_TIMING_STARTUP);
508 
509 	/*
510 	 * Quirk: the i2c controller may get confused right after the
511 	 * wake-up signal has been sent.  As a workaround, do a dummy read.
512 	 * If the read fails, the controller will probably be reset so that
513 	 * further reads will work.
514 	 */
515 	i2c_smbus_read_word_data(data->client, chip_info->op_eeprom_config1);
516 
517 	return 0;
518 }
519 
520 /* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
mlx90614_probe_wakeup(struct i2c_client * client)521 static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
522 {
523 	struct gpio_desc *gpio;
524 
525 	if (!i2c_check_functionality(client->adapter,
526 						I2C_FUNC_SMBUS_WRITE_BYTE)) {
527 		dev_info(&client->dev,
528 			 "i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
529 		return NULL;
530 	}
531 
532 	gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
533 
534 	if (IS_ERR(gpio)) {
535 		dev_warn(&client->dev,
536 			 "gpio acquisition failed with error %ld, sleep disabled",
537 			 PTR_ERR(gpio));
538 		return NULL;
539 	} else if (!gpio) {
540 		dev_info(&client->dev,
541 			 "wakeup-gpio not found, sleep disabled");
542 	}
543 
544 	return gpio;
545 }
546 #else
mlx90614_sleep(struct mlx90614_data * data)547 static inline int mlx90614_sleep(struct mlx90614_data *data)
548 {
549 	return -ENOSYS;
550 }
mlx90614_wakeup(struct mlx90614_data * data)551 static inline int mlx90614_wakeup(struct mlx90614_data *data)
552 {
553 	return -ENOSYS;
554 }
mlx90614_probe_wakeup(struct i2c_client * client)555 static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
556 {
557 	return NULL;
558 }
559 #endif
560 
561 /* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
mlx90614_probe_num_ir_sensors(struct i2c_client * client)562 static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
563 {
564 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
565 	struct mlx90614_data *data = iio_priv(indio_dev);
566 	const struct mlx_chip_info *chip_info = data->chip_info;
567 	s32 ret;
568 
569 	if (chip_info->dual_channel)
570 		return 0;
571 
572 	ret = i2c_smbus_read_word_data(client, chip_info->op_eeprom_config1);
573 
574 	if (ret < 0)
575 		return ret;
576 
577 	return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
578 }
579 
mlx90614_probe(struct i2c_client * client)580 static int mlx90614_probe(struct i2c_client *client)
581 {
582 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
583 	struct iio_dev *indio_dev;
584 	struct mlx90614_data *data;
585 	int ret;
586 
587 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
588 		return -EOPNOTSUPP;
589 
590 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
591 	if (!indio_dev)
592 		return -ENOMEM;
593 
594 	data = iio_priv(indio_dev);
595 	i2c_set_clientdata(client, indio_dev);
596 	data->client = client;
597 	mutex_init(&data->lock);
598 	data->wakeup_gpio = mlx90614_probe_wakeup(client);
599 	data->chip_info = i2c_get_match_data(client);
600 
601 	mlx90614_wakeup(data);
602 
603 	indio_dev->name = id->name;
604 	indio_dev->modes = INDIO_DIRECT_MODE;
605 	indio_dev->info = &mlx90614_info;
606 
607 	ret = mlx90614_probe_num_ir_sensors(client);
608 	switch (ret) {
609 	case 0:
610 		dev_dbg(&client->dev, "Found single sensor");
611 		indio_dev->channels = mlx90614_channels;
612 		indio_dev->num_channels = 2;
613 		break;
614 	case 1:
615 		dev_dbg(&client->dev, "Found dual sensor");
616 		indio_dev->channels = mlx90614_channels;
617 		indio_dev->num_channels = 3;
618 		break;
619 	default:
620 		return ret;
621 	}
622 
623 	if (data->wakeup_gpio) {
624 		pm_runtime_set_autosuspend_delay(&client->dev,
625 						 MLX90614_AUTOSLEEP_DELAY);
626 		pm_runtime_use_autosuspend(&client->dev);
627 		pm_runtime_set_active(&client->dev);
628 		pm_runtime_enable(&client->dev);
629 	}
630 
631 	return iio_device_register(indio_dev);
632 }
633 
mlx90614_remove(struct i2c_client * client)634 static void mlx90614_remove(struct i2c_client *client)
635 {
636 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
637 	struct mlx90614_data *data = iio_priv(indio_dev);
638 
639 	iio_device_unregister(indio_dev);
640 
641 	if (data->wakeup_gpio) {
642 		pm_runtime_disable(&client->dev);
643 		if (!pm_runtime_status_suspended(&client->dev))
644 			mlx90614_sleep(data);
645 		pm_runtime_set_suspended(&client->dev);
646 	}
647 }
648 
649 static const struct mlx_chip_info mlx90614_chip_info = {
650 	.op_eeprom_emissivity		= MLX90614_OP_EEPROM | 0x04,
651 	.op_eeprom_config1		= MLX90614_OP_EEPROM | 0x05,
652 	.op_ram_ta			= MLX90614_OP_RAM | 0x06,
653 	.op_ram_tobj1			= MLX90614_OP_RAM | 0x07,
654 	.op_ram_tobj2			= MLX90614_OP_RAM | 0x08,
655 	.op_sleep			= MLX90614_OP_SLEEP,
656 	.dual_channel			= true,
657 	.wakeup_delay_ms		= MLX90614_TIMING_WAKEUP,
658 	.emissivity_max			= 65535,
659 	.fir_config_mask		= MLX90614_CONFIG_FIR_MASK,
660 	.iir_config_mask		= MLX90614_CONFIG_IIR_MASK,
661 	.iir_valid_offset		= 0,
662 	.iir_values			= { 77, 31, 20, 15, 723, 153, 110, 86 },
663 	.iir_freqs			= {
664 		{ 0, 150000 },	/* 13% ~= 0.15 Hz */
665 		{ 0, 200000 },	/* 17% ~= 0.20 Hz */
666 		{ 0, 310000 },	/* 25% ~= 0.31 Hz */
667 		{ 0, 770000 },	/* 50% ~= 0.77 Hz */
668 		{ 0, 860000 },	/* 57% ~= 0.86 Hz */
669 		{ 1, 100000 },	/* 67% ~= 1.10 Hz */
670 		{ 1, 530000 },	/* 80% ~= 1.53 Hz */
671 		{ 7, 230000 }	/* 100% ~= 7.23 Hz */
672 	},
673 };
674 
675 static const struct mlx_chip_info mlx90615_chip_info = {
676 	.op_eeprom_emissivity		= MLX90615_OP_EEPROM | 0x03,
677 	.op_eeprom_config1		= MLX90615_OP_EEPROM | 0x02,
678 	.op_ram_ta			= MLX90615_OP_RAM | 0x06,
679 	.op_ram_tobj1			= MLX90615_OP_RAM | 0x07,
680 	.op_ram_tobj2			= MLX90615_OP_RAM | 0x08,
681 	.op_sleep			= MLX90615_OP_SLEEP,
682 	.dual_channel			= false,
683 	.wakeup_delay_ms		= MLX90615_TIMING_WAKEUP,
684 	.emissivity_max			= 16383,
685 	.fir_config_mask		= 0,	/* MLX90615 FIR is fixed */
686 	.iir_config_mask		= MLX90615_CONFIG_IIR_MASK,
687 	/* IIR value 0 is FORBIDDEN COMBINATION on MLX90615 */
688 	.iir_valid_offset		= 1,
689 	.iir_values			= { 500, 50, 30, 20, 15, 13, 10 },
690 	.iir_freqs			= {
691 		{ 0, 100000 },	/* 14% ~= 0.10 Hz */
692 		{ 0, 130000 },	/* 17% ~= 0.13 Hz */
693 		{ 0, 150000 },	/* 20% ~= 0.15 Hz */
694 		{ 0, 200000 },	/* 25% ~= 0.20 Hz */
695 		{ 0, 300000 },	/* 33% ~= 0.30 Hz */
696 		{ 0, 500000 },	/* 50% ~= 0.50 Hz */
697 		{ 5, 000000 },	/* 100% ~= 5.00 Hz */
698 	},
699 };
700 
701 static const struct i2c_device_id mlx90614_id[] = {
702 	{ "mlx90614", .driver_data = (kernel_ulong_t)&mlx90614_chip_info },
703 	{ "mlx90615", .driver_data = (kernel_ulong_t)&mlx90615_chip_info },
704 	{ }
705 };
706 MODULE_DEVICE_TABLE(i2c, mlx90614_id);
707 
708 static const struct of_device_id mlx90614_of_match[] = {
709 	{ .compatible = "melexis,mlx90614", .data = &mlx90614_chip_info },
710 	{ .compatible = "melexis,mlx90615", .data = &mlx90615_chip_info },
711 	{ }
712 };
713 MODULE_DEVICE_TABLE(of, mlx90614_of_match);
714 
mlx90614_pm_suspend(struct device * dev)715 static int mlx90614_pm_suspend(struct device *dev)
716 {
717 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
718 	struct mlx90614_data *data = iio_priv(indio_dev);
719 
720 	if (data->wakeup_gpio && pm_runtime_active(dev))
721 		return mlx90614_sleep(data);
722 
723 	return 0;
724 }
725 
mlx90614_pm_resume(struct device * dev)726 static int mlx90614_pm_resume(struct device *dev)
727 {
728 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
729 	struct mlx90614_data *data = iio_priv(indio_dev);
730 	int err;
731 
732 	if (data->wakeup_gpio) {
733 		err = mlx90614_wakeup(data);
734 		if (err < 0)
735 			return err;
736 
737 		pm_runtime_disable(dev);
738 		pm_runtime_set_active(dev);
739 		pm_runtime_enable(dev);
740 	}
741 
742 	return 0;
743 }
744 
mlx90614_pm_runtime_suspend(struct device * dev)745 static int mlx90614_pm_runtime_suspend(struct device *dev)
746 {
747 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
748 	struct mlx90614_data *data = iio_priv(indio_dev);
749 
750 	return mlx90614_sleep(data);
751 }
752 
mlx90614_pm_runtime_resume(struct device * dev)753 static int mlx90614_pm_runtime_resume(struct device *dev)
754 {
755 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
756 	struct mlx90614_data *data = iio_priv(indio_dev);
757 
758 	return mlx90614_wakeup(data);
759 }
760 
761 static const struct dev_pm_ops mlx90614_pm_ops = {
762 	SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
763 	RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
764 		       mlx90614_pm_runtime_resume, NULL)
765 };
766 
767 static struct i2c_driver mlx90614_driver = {
768 	.driver = {
769 		.name	= "mlx90614",
770 		.of_match_table = mlx90614_of_match,
771 		.pm	= pm_ptr(&mlx90614_pm_ops),
772 	},
773 	.probe = mlx90614_probe,
774 	.remove = mlx90614_remove,
775 	.id_table = mlx90614_id,
776 };
777 module_i2c_driver(mlx90614_driver);
778 
779 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
780 MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
781 MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
782 MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
783 MODULE_LICENSE("GPL");
784