root/drivers/iio/temperature/mlx90614.c

DEFINITIONS

1. mlx90614_write_word
2. mlx90614_iir_search
3. mlx90614_power_get
4. mlx90614_power_put
5. mlx90614_power_get
6. mlx90614_power_put
7. mlx90614_read_raw
8. mlx90614_write_raw
9. mlx90614_write_raw_get_fmt
10. mlx90614_sleep
11. mlx90614_wakeup
12. mlx90614_probe_wakeup
13. mlx90614_sleep
14. mlx90614_wakeup
15. mlx90614_probe_wakeup
16. mlx90614_probe_num_ir_sensors
17. mlx90614_probe
18. mlx90614_remove
19. mlx90614_pm_suspend
20. mlx90614_pm_resume
21. mlx90614_pm_runtime_suspend
22. mlx90614_pm_runtime_resume

   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 IIO_CONST_ATTR(in_temp_object_filter_low_pass_3db_frequency_available,
  83                       "0.15 0.20 0.31 0.77 0.86 1.10 1.53 7.23");
  84 
  85 static struct attribute *mlx90614_attributes[] = {
  86         &iio_const_attr_in_temp_object_filter_low_pass_3db_frequency_available.dev_attr.attr,
  87         NULL,
  88 };
  89 
  90 static const struct attribute_group mlx90614_attr_group = {
  91         .attrs = mlx90614_attributes,
  92 };
  93 
  94 /*
  95  * Erase an address and write word.
  96  * The mutex must be locked before calling.
  97  */
  98 static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
  99                                u16 value)
 100 {
 101         /*
 102          * Note: The mlx90614 requires a PEC on writing but does not send us a
 103          * valid PEC on reading.  Hence, we cannot set I2C_CLIENT_PEC in
 104          * i2c_client.flags.  As a workaround, we use i2c_smbus_xfer here.
 105          */
 106         union i2c_smbus_data data;
 107         s32 ret;
 108 
 109         dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
 110 
 111         data.word = 0x0000; /* erase command */
 112         ret = i2c_smbus_xfer(client->adapter, client->addr,
 113                              client->flags | I2C_CLIENT_PEC,
 114                              I2C_SMBUS_WRITE, command,
 115                              I2C_SMBUS_WORD_DATA, &data);
 116         if (ret < 0)
 117                 return ret;
 118 
 119         msleep(MLX90614_TIMING_EEPROM);
 120 
 121         data.word = value; /* actual write */
 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 
 127         msleep(MLX90614_TIMING_EEPROM);
 128 
 129         return ret;
 130 }
 131 
 132 /*
 133  * Find the IIR value inside mlx90614_iir_values array and return its position
 134  * which is equivalent to the bit value in sensor register
 135  */
 136 static inline s32 mlx90614_iir_search(const struct i2c_client *client,
 137                                       int value)
 138 {
 139         int i;
 140         s32 ret;
 141 
 142         for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
 143                 if (value == mlx90614_iir_values[i])
 144                         break;
 145         }
 146 
 147         if (i == ARRAY_SIZE(mlx90614_iir_values))
 148                 return -EINVAL;
 149 
 150         /*
 151          * CONFIG register values must not be changed so
 152          * we must read them before we actually write
 153          * changes
 154          */
 155         ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
 156         if (ret < 0)
 157                 return ret;
 158 
 159         ret &= ~MLX90614_CONFIG_FIR_MASK;
 160         ret |= MLX90614_CONST_FIR << MLX90614_CONFIG_FIR_SHIFT;
 161         ret &= ~MLX90614_CONFIG_IIR_MASK;
 162         ret |= i << MLX90614_CONFIG_IIR_SHIFT;
 163 
 164         /* Write changed values */
 165         ret = mlx90614_write_word(client, MLX90614_CONFIG, ret);
 166         return ret;
 167 }
 168 
 169 #ifdef CONFIG_PM
 170 /*
 171  * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
 172  * the last wake-up.  This is normally only needed to get a valid temperature
 173  * reading.  EEPROM access does not need such delay.
 174  * Return 0 on success, <0 on error.
 175  */
 176 static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
 177 {
 178         unsigned long now;
 179 
 180         if (!data->wakeup_gpio)
 181                 return 0;
 182 
 183         pm_runtime_get_sync(&data->client->dev);
 184 
 185         if (startup) {
 186                 now = jiffies;
 187                 if (time_before(now, data->ready_timestamp) &&
 188                     msleep_interruptible(jiffies_to_msecs(
 189                                 data->ready_timestamp - now)) != 0) {
 190                         pm_runtime_put_autosuspend(&data->client->dev);
 191                         return -EINTR;
 192                 }
 193         }
 194 
 195         return 0;
 196 }
 197 
 198 static void mlx90614_power_put(struct mlx90614_data *data)
 199 {
 200         if (!data->wakeup_gpio)
 201                 return;
 202 
 203         pm_runtime_mark_last_busy(&data->client->dev);
 204         pm_runtime_put_autosuspend(&data->client->dev);
 205 }
 206 #else
 207 static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
 208 {
 209         return 0;
 210 }
 211 
 212 static inline void mlx90614_power_put(struct mlx90614_data *data)
 213 {
 214 }
 215 #endif
 216 
 217 static int mlx90614_read_raw(struct iio_dev *indio_dev,
 218                             struct iio_chan_spec const *channel, int *val,
 219                             int *val2, long mask)
 220 {
 221         struct mlx90614_data *data = iio_priv(indio_dev);
 222         u8 cmd;
 223         s32 ret;
 224 
 225         switch (mask) {
 226         case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
 227                 switch (channel->channel2) {
 228                 case IIO_MOD_TEMP_AMBIENT:
 229                         cmd = MLX90614_TA;
 230                         break;
 231                 case IIO_MOD_TEMP_OBJECT:
 232                         switch (channel->channel) {
 233                         case 0:
 234                                 cmd = MLX90614_TOBJ1;
 235                                 break;
 236                         case 1:
 237                                 cmd = MLX90614_TOBJ2;
 238                                 break;
 239                         default:
 240                                 return -EINVAL;
 241                         }
 242                         break;
 243                 default:
 244                         return -EINVAL;
 245                 }
 246 
 247                 ret = mlx90614_power_get(data, true);
 248                 if (ret < 0)
 249                         return ret;
 250                 ret = i2c_smbus_read_word_data(data->client, cmd);
 251                 mlx90614_power_put(data);
 252 
 253                 if (ret < 0)
 254                         return ret;
 255 
 256                 /* MSB is an error flag */
 257                 if (ret & 0x8000)
 258                         return -EIO;
 259 
 260                 *val = ret;
 261                 return IIO_VAL_INT;
 262         case IIO_CHAN_INFO_OFFSET:
 263                 *val = MLX90614_CONST_OFFSET_DEC;
 264                 *val2 = MLX90614_CONST_OFFSET_REM;
 265                 return IIO_VAL_INT_PLUS_MICRO;
 266         case IIO_CHAN_INFO_SCALE:
 267                 *val = MLX90614_CONST_SCALE;
 268                 return IIO_VAL_INT;
 269         case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
 270                 mlx90614_power_get(data, false);
 271                 mutex_lock(&data->lock);
 272                 ret = i2c_smbus_read_word_data(data->client,
 273                                                MLX90614_EMISSIVITY);
 274                 mutex_unlock(&data->lock);
 275                 mlx90614_power_put(data);
 276 
 277                 if (ret < 0)
 278                         return ret;
 279 
 280                 if (ret == MLX90614_CONST_RAW_EMISSIVITY_MAX) {
 281                         *val = 1;
 282                         *val2 = 0;
 283                 } else {
 284                         *val = 0;
 285                         *val2 = ret * MLX90614_CONST_EMISSIVITY_RESOLUTION;
 286                 }
 287                 return IIO_VAL_INT_PLUS_NANO;
 288         case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
 289                                                              FIR = 1024 */
 290                 mlx90614_power_get(data, false);
 291                 mutex_lock(&data->lock);
 292                 ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
 293                 mutex_unlock(&data->lock);
 294                 mlx90614_power_put(data);
 295 
 296                 if (ret < 0)
 297                         return ret;
 298 
 299                 *val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
 300                 *val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100) *
 301                         10000;
 302                 return IIO_VAL_INT_PLUS_MICRO;
 303         default:
 304                 return -EINVAL;
 305         }
 306 }
 307 
 308 static int mlx90614_write_raw(struct iio_dev *indio_dev,
 309                              struct iio_chan_spec const *channel, int val,
 310                              int val2, long mask)
 311 {
 312         struct mlx90614_data *data = iio_priv(indio_dev);
 313         s32 ret;
 314 
 315         switch (mask) {
 316         case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
 317                 if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
 318                         return -EINVAL;
 319                 val = val * MLX90614_CONST_RAW_EMISSIVITY_MAX +
 320                         val2 / MLX90614_CONST_EMISSIVITY_RESOLUTION;
 321 
 322                 mlx90614_power_get(data, false);
 323                 mutex_lock(&data->lock);
 324                 ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,
 325                                           val);
 326                 mutex_unlock(&data->lock);
 327                 mlx90614_power_put(data);
 328 
 329                 return ret;
 330         case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
 331                 if (val < 0 || val2 < 0)
 332                         return -EINVAL;
 333 
 334                 mlx90614_power_get(data, false);
 335                 mutex_lock(&data->lock);
 336                 ret = mlx90614_iir_search(data->client,
 337                                           val * 100 + val2 / 10000);
 338                 mutex_unlock(&data->lock);
 339                 mlx90614_power_put(data);
 340 
 341                 return ret;
 342         default:
 343                 return -EINVAL;
 344         }
 345 }
 346 
 347 static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
 348                                      struct iio_chan_spec const *channel,
 349                                      long mask)
 350 {
 351         switch (mask) {
 352         case IIO_CHAN_INFO_CALIBEMISSIVITY:
 353                 return IIO_VAL_INT_PLUS_NANO;
 354         case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
 355                 return IIO_VAL_INT_PLUS_MICRO;
 356         default:
 357                 return -EINVAL;
 358         }
 359 }
 360 
 361 static const struct iio_chan_spec mlx90614_channels[] = {
 362         {
 363                 .type = IIO_TEMP,
 364                 .modified = 1,
 365                 .channel2 = IIO_MOD_TEMP_AMBIENT,
 366                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 367                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 368                     BIT(IIO_CHAN_INFO_SCALE),
 369         },
 370         {
 371                 .type = IIO_TEMP,
 372                 .modified = 1,
 373                 .channel2 = IIO_MOD_TEMP_OBJECT,
 374                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 375                     BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
 376                         BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
 377                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 378                     BIT(IIO_CHAN_INFO_SCALE),
 379         },
 380         {
 381                 .type = IIO_TEMP,
 382                 .indexed = 1,
 383                 .modified = 1,
 384                 .channel = 1,
 385                 .channel2 = IIO_MOD_TEMP_OBJECT,
 386                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 387                     BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
 388                         BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
 389                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 390                     BIT(IIO_CHAN_INFO_SCALE),
 391         },
 392 };
 393 
 394 static const struct iio_info mlx90614_info = {
 395         .read_raw = mlx90614_read_raw,
 396         .write_raw = mlx90614_write_raw,
 397         .write_raw_get_fmt = mlx90614_write_raw_get_fmt,
 398         .attrs = &mlx90614_attr_group,
 399 };
 400 
 401 #ifdef CONFIG_PM
 402 static int mlx90614_sleep(struct mlx90614_data *data)
 403 {
 404         s32 ret;
 405 
 406         if (!data->wakeup_gpio) {
 407                 dev_dbg(&data->client->dev, "Sleep disabled");
 408                 return -ENOSYS;
 409         }
 410 
 411         dev_dbg(&data->client->dev, "Requesting sleep");
 412 
 413         mutex_lock(&data->lock);
 414         ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
 415                              data->client->flags | I2C_CLIENT_PEC,
 416                              I2C_SMBUS_WRITE, MLX90614_OP_SLEEP,
 417                              I2C_SMBUS_BYTE, NULL);
 418         mutex_unlock(&data->lock);
 419 
 420         return ret;
 421 }
 422 
 423 static int mlx90614_wakeup(struct mlx90614_data *data)
 424 {
 425         if (!data->wakeup_gpio) {
 426                 dev_dbg(&data->client->dev, "Wake-up disabled");
 427                 return -ENOSYS;
 428         }
 429 
 430         dev_dbg(&data->client->dev, "Requesting wake-up");
 431 
 432         i2c_lock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
 433         gpiod_direction_output(data->wakeup_gpio, 0);
 434         msleep(MLX90614_TIMING_WAKEUP);
 435         gpiod_direction_input(data->wakeup_gpio);
 436         i2c_unlock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
 437 
 438         data->ready_timestamp = jiffies +
 439                         msecs_to_jiffies(MLX90614_TIMING_STARTUP);
 440 
 441         /*
 442          * Quirk: the i2c controller may get confused right after the
 443          * wake-up signal has been sent.  As a workaround, do a dummy read.
 444          * If the read fails, the controller will probably be reset so that
 445          * further reads will work.
 446          */
 447         i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
 448 
 449         return 0;
 450 }
 451 
 452 /* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
 453 static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
 454 {
 455         struct gpio_desc *gpio;
 456 
 457         if (!i2c_check_functionality(client->adapter,
 458                                                 I2C_FUNC_SMBUS_WRITE_BYTE)) {
 459                 dev_info(&client->dev,
 460                          "i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
 461                 return NULL;
 462         }
 463 
 464         gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
 465 
 466         if (IS_ERR(gpio)) {
 467                 dev_warn(&client->dev,
 468                          "gpio acquisition failed with error %ld, sleep disabled",
 469                          PTR_ERR(gpio));
 470                 return NULL;
 471         } else if (!gpio) {
 472                 dev_info(&client->dev,
 473                          "wakeup-gpio not found, sleep disabled");
 474         }
 475 
 476         return gpio;
 477 }
 478 #else
 479 static inline int mlx90614_sleep(struct mlx90614_data *data)
 480 {
 481         return -ENOSYS;
 482 }
 483 static inline int mlx90614_wakeup(struct mlx90614_data *data)
 484 {
 485         return -ENOSYS;
 486 }
 487 static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
 488 {
 489         return NULL;
 490 }
 491 #endif
 492 
 493 /* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
 494 static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
 495 {
 496         s32 ret;
 497 
 498         ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
 499 
 500         if (ret < 0)
 501                 return ret;
 502 
 503         return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
 504 }
 505 
 506 static int mlx90614_probe(struct i2c_client *client,
 507                          const struct i2c_device_id *id)
 508 {
 509         struct iio_dev *indio_dev;
 510         struct mlx90614_data *data;
 511         int ret;
 512 
 513         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 514                 return -EOPNOTSUPP;
 515 
 516         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 517         if (!indio_dev)
 518                 return -ENOMEM;
 519 
 520         data = iio_priv(indio_dev);
 521         i2c_set_clientdata(client, indio_dev);
 522         data->client = client;
 523         mutex_init(&data->lock);
 524         data->wakeup_gpio = mlx90614_probe_wakeup(client);
 525 
 526         mlx90614_wakeup(data);
 527 
 528         indio_dev->dev.parent = &client->dev;
 529         indio_dev->name = id->name;
 530         indio_dev->modes = INDIO_DIRECT_MODE;
 531         indio_dev->info = &mlx90614_info;
 532 
 533         ret = mlx90614_probe_num_ir_sensors(client);
 534         switch (ret) {
 535         case 0:
 536                 dev_dbg(&client->dev, "Found single sensor");
 537                 indio_dev->channels = mlx90614_channels;
 538                 indio_dev->num_channels = 2;
 539                 break;
 540         case 1:
 541                 dev_dbg(&client->dev, "Found dual sensor");
 542                 indio_dev->channels = mlx90614_channels;
 543                 indio_dev->num_channels = 3;
 544                 break;
 545         default:
 546                 return ret;
 547         }
 548 
 549         if (data->wakeup_gpio) {
 550                 pm_runtime_set_autosuspend_delay(&client->dev,
 551                                                  MLX90614_AUTOSLEEP_DELAY);
 552                 pm_runtime_use_autosuspend(&client->dev);
 553                 pm_runtime_set_active(&client->dev);
 554                 pm_runtime_enable(&client->dev);
 555         }
 556 
 557         return iio_device_register(indio_dev);
 558 }
 559 
 560 static int mlx90614_remove(struct i2c_client *client)
 561 {
 562         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 563         struct mlx90614_data *data = iio_priv(indio_dev);
 564 
 565         iio_device_unregister(indio_dev);
 566 
 567         if (data->wakeup_gpio) {
 568                 pm_runtime_disable(&client->dev);
 569                 if (!pm_runtime_status_suspended(&client->dev))
 570                         mlx90614_sleep(data);
 571                 pm_runtime_set_suspended(&client->dev);
 572         }
 573 
 574         return 0;
 575 }
 576 
 577 static const struct i2c_device_id mlx90614_id[] = {
 578         { "mlx90614", 0 },
 579         { }
 580 };
 581 MODULE_DEVICE_TABLE(i2c, mlx90614_id);
 582 
 583 static const struct of_device_id mlx90614_of_match[] = {
 584         { .compatible = "melexis,mlx90614" },
 585         { }
 586 };
 587 MODULE_DEVICE_TABLE(of, mlx90614_of_match);
 588 
 589 #ifdef CONFIG_PM_SLEEP
 590 static int mlx90614_pm_suspend(struct device *dev)
 591 {
 592         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 593         struct mlx90614_data *data = iio_priv(indio_dev);
 594 
 595         if (data->wakeup_gpio && pm_runtime_active(dev))
 596                 return mlx90614_sleep(data);
 597 
 598         return 0;
 599 }
 600 
 601 static int mlx90614_pm_resume(struct device *dev)
 602 {
 603         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 604         struct mlx90614_data *data = iio_priv(indio_dev);
 605         int err;
 606 
 607         if (data->wakeup_gpio) {
 608                 err = mlx90614_wakeup(data);
 609                 if (err < 0)
 610                         return err;
 611 
 612                 pm_runtime_disable(dev);
 613                 pm_runtime_set_active(dev);
 614                 pm_runtime_enable(dev);
 615         }
 616 
 617         return 0;
 618 }
 619 #endif
 620 
 621 #ifdef CONFIG_PM
 622 static int mlx90614_pm_runtime_suspend(struct device *dev)
 623 {
 624         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 625         struct mlx90614_data *data = iio_priv(indio_dev);
 626 
 627         return mlx90614_sleep(data);
 628 }
 629 
 630 static int mlx90614_pm_runtime_resume(struct device *dev)
 631 {
 632         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 633         struct mlx90614_data *data = iio_priv(indio_dev);
 634 
 635         return mlx90614_wakeup(data);
 636 }
 637 #endif
 638 
 639 static const struct dev_pm_ops mlx90614_pm_ops = {
 640         SET_SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
 641         SET_RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
 642                            mlx90614_pm_runtime_resume, NULL)
 643 };
 644 
 645 static struct i2c_driver mlx90614_driver = {
 646         .driver = {
 647                 .name   = "mlx90614",
 648                 .of_match_table = mlx90614_of_match,
 649                 .pm     = &mlx90614_pm_ops,
 650         },
 651         .probe = mlx90614_probe,
 652         .remove = mlx90614_remove,
 653         .id_table = mlx90614_id,
 654 };
 655 module_i2c_driver(mlx90614_driver);
 656 
 657 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 658 MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
 659 MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
 660 MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
 661 MODULE_LICENSE("GPL");