drivers/staging/iio/light/isl29018.c

   1 /*
   2  * A iio driver for the light sensor ISL 29018.
   3  *
   4  * IIO driver for monitoring ambient light intensity in luxi, proximity
   5  * sensing and infrared sensing.
   6  *
   7  * Copyright (c) 2010, NVIDIA Corporation.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/i2c.h>
  26 #include <linux/err.h>
  27 #include <linux/mutex.h>
  28 #include <linux/delay.h>
  29 #include <linux/regmap.h>
  30 #include <linux/slab.h>
  31 #include <linux/iio/iio.h>
  32 #include <linux/iio/sysfs.h>
  33
  34 #define CONVERSION_TIME_MS              100
  35
  36 #define ISL29018_REG_ADD_COMMAND1       0x00
  37 #define COMMMAND1_OPMODE_SHIFT          5
  38 #define COMMMAND1_OPMODE_MASK           (7 << COMMMAND1_OPMODE_SHIFT)
  39 #define COMMMAND1_OPMODE_POWER_DOWN     0
  40 #define COMMMAND1_OPMODE_ALS_ONCE       1
  41 #define COMMMAND1_OPMODE_IR_ONCE        2
  42 #define COMMMAND1_OPMODE_PROX_ONCE      3
  43
  44 #define ISL29018_REG_ADD_COMMANDII      0x01
  45 #define COMMANDII_RESOLUTION_SHIFT      2
  46 #define COMMANDII_RESOLUTION_MASK       (0x3 << COMMANDII_RESOLUTION_SHIFT)
  47
  48 #define COMMANDII_RANGE_SHIFT           0
  49 #define COMMANDII_RANGE_MASK            (0x3 << COMMANDII_RANGE_SHIFT)
  50
  51 #define COMMANDII_SCHEME_SHIFT          7
  52 #define COMMANDII_SCHEME_MASK           (0x1 << COMMANDII_SCHEME_SHIFT)
  53
  54 #define ISL29018_REG_ADD_DATA_LSB       0x02
  55 #define ISL29018_REG_ADD_DATA_MSB       0x03
  56
  57 #define ISL29018_REG_TEST               0x08
  58 #define ISL29018_TEST_SHIFT             0
  59 #define ISL29018_TEST_MASK              (0xFF << ISL29018_TEST_SHIFT)
  60
  61 struct isl29018_chip {
  62         struct device           *dev;
  63         struct regmap           *regmap;
  64         struct mutex            lock;
  65         unsigned int            lux_scale;
  66         unsigned int            lux_uscale;
  67         unsigned int            range;
  68         unsigned int            adc_bit;
  69         int                     prox_scheme;
  70         bool                    suspended;
  71 };
  72
  73 static int isl29018_set_range(struct isl29018_chip *chip, unsigned long range,
  74                 unsigned int *new_range)
  75 {
  76         static const unsigned long supp_ranges[] = {1000, 4000, 16000, 64000};
  77         int i;
  78
  79         for (i = 0; i < ARRAY_SIZE(supp_ranges); ++i) {
  80                 if (range <= supp_ranges[i]) {
  81                         *new_range = (unsigned int)supp_ranges[i];
  82                         break;
  83                 }
  84         }
  85
  86         if (i >= ARRAY_SIZE(supp_ranges))
  87                 return -EINVAL;
  88
  89         return regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMANDII,
  90                         COMMANDII_RANGE_MASK, i << COMMANDII_RANGE_SHIFT);
  91 }
  92
  93 static int isl29018_set_resolution(struct isl29018_chip *chip,
  94                         unsigned long adcbit, unsigned int *conf_adc_bit)
  95 {
  96         static const unsigned long supp_adcbit[] = {16, 12, 8, 4};
  97         int i;
  98
  99         for (i = 0; i < ARRAY_SIZE(supp_adcbit); ++i) {
 100                 if (adcbit >= supp_adcbit[i]) {
 101                         *conf_adc_bit = (unsigned int)supp_adcbit[i];
 102                         break;
 103                 }
 104         }
 105
 106         if (i >= ARRAY_SIZE(supp_adcbit))
 107                 return -EINVAL;
 108
 109         return regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMANDII,
 110                         COMMANDII_RESOLUTION_MASK,
 111                         i << COMMANDII_RESOLUTION_SHIFT);
 112 }
 113
 114 static int isl29018_read_sensor_input(struct isl29018_chip *chip, int mode)
 115 {
 116         int status;
 117         unsigned int lsb;
 118         unsigned int msb;
 119
 120         /* Set mode */
 121         status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1,
 122                         mode << COMMMAND1_OPMODE_SHIFT);
 123         if (status) {
 124                 dev_err(chip->dev,
 125                         "Error in setting operating mode err %d\n", status);
 126                 return status;
 127         }
 128         msleep(CONVERSION_TIME_MS);
 129         status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_LSB, &lsb);
 130         if (status < 0) {
 131                 dev_err(chip->dev,
 132                         "Error in reading LSB DATA with err %d\n", status);
 133                 return status;
 134         }
 135
 136         status = regmap_read(chip->regmap, ISL29018_REG_ADD_DATA_MSB, &msb);
 137         if (status < 0) {
 138                 dev_err(chip->dev,
 139                         "Error in reading MSB DATA with error %d\n", status);
 140                 return status;
 141         }
 142         dev_vdbg(chip->dev, "MSB 0x%x and LSB 0x%x\n", msb, lsb);
 143
 144         return (msb << 8) | lsb;
 145 }
 146
 147 static int isl29018_read_lux(struct isl29018_chip *chip, int *lux)
 148 {
 149         int lux_data;
 150         unsigned int data_x_range, lux_unshifted;
 151
 152         lux_data = isl29018_read_sensor_input(chip, COMMMAND1_OPMODE_ALS_ONCE);
 153
 154         if (lux_data < 0)
 155                 return lux_data;
 156
 157         /* To support fractional scaling, separate the unshifted lux
 158          * into two calculations: int scaling and micro-scaling.
 159          * lux_uscale ranges from 0-999999, so about 20 bits.  Split
 160          * the /1,000,000 in two to reduce the risk of over/underflow.
 161          */
 162         data_x_range = lux_data * chip->range;
 163         lux_unshifted = data_x_range * chip->lux_scale;
 164         lux_unshifted += data_x_range / 1000 * chip->lux_uscale / 1000;
 165         *lux = lux_unshifted >> chip->adc_bit;
 166
 167         return 0;
 168 }
 169
 170 static int isl29018_read_ir(struct isl29018_chip *chip, int *ir)
 171 {
 172         int ir_data;
 173
 174         ir_data = isl29018_read_sensor_input(chip, COMMMAND1_OPMODE_IR_ONCE);
 175
 176         if (ir_data < 0)
 177                 return ir_data;
 178
 179         *ir = ir_data;
 180
 181         return 0;
 182 }
 183
 184 static int isl29018_read_proximity_ir(struct isl29018_chip *chip, int scheme,
 185                 int *near_ir)
 186 {
 187         int status;
 188         int prox_data = -1;
 189         int ir_data = -1;
 190
 191         /* Do proximity sensing with required scheme */
 192         status = regmap_update_bits(chip->regmap, ISL29018_REG_ADD_COMMANDII,
 193                         COMMANDII_SCHEME_MASK,
 194                         scheme << COMMANDII_SCHEME_SHIFT);
 195         if (status) {
 196                 dev_err(chip->dev, "Error in setting operating mode\n");
 197                 return status;
 198         }
 199
 200         prox_data = isl29018_read_sensor_input(chip,
 201                                         COMMMAND1_OPMODE_PROX_ONCE);
 202         if (prox_data < 0)
 203                 return prox_data;
 204
 205         if (scheme == 1) {
 206                 *near_ir = prox_data;
 207                 return 0;
 208         }
 209
 210         ir_data = isl29018_read_sensor_input(chip, COMMMAND1_OPMODE_IR_ONCE);
 211
 212         if (ir_data < 0)
 213                 return ir_data;
 214
 215         if (prox_data >= ir_data)
 216                 *near_ir = prox_data - ir_data;
 217         else
 218                 *near_ir = 0;
 219
 220         return 0;
 221 }
 222
 223 /* Sysfs interface */
 224 /* range */
 225 static ssize_t show_range(struct device *dev,
 226                         struct device_attribute *attr, char *buf)
 227 {
 228         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 229         struct isl29018_chip *chip = iio_priv(indio_dev);
 230
 231         return sprintf(buf, "%u\n", chip->range);
 232 }
 233
 234 static ssize_t store_range(struct device *dev,
 235                 struct device_attribute *attr, const char *buf, size_t count)
 236 {
 237         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 238         struct isl29018_chip *chip = iio_priv(indio_dev);
 239         int status;
 240         unsigned long lval;
 241         unsigned int new_range;
 242
 243         if (strict_strtoul(buf, 10, &lval))
 244                 return -EINVAL;
 245
 246         if (!(lval == 1000UL || lval == 4000UL ||
 247                         lval == 16000UL || lval == 64000UL)) {
 248                 dev_err(dev, "The range is not supported\n");
 249                 return -EINVAL;
 250         }
 251
 252         mutex_lock(&chip->lock);
 253         status = isl29018_set_range(chip, lval, &new_range);
 254         if (status < 0) {
 255                 mutex_unlock(&chip->lock);
 256                 dev_err(dev,
 257                         "Error in setting max range with err %d\n", status);
 258                 return status;
 259         }
 260         chip->range = new_range;
 261         mutex_unlock(&chip->lock);
 262
 263         return count;
 264 }
 265
 266 /* resolution */
 267 static ssize_t show_resolution(struct device *dev,
 268                         struct device_attribute *attr, char *buf)
 269 {
 270         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 271         struct isl29018_chip *chip = iio_priv(indio_dev);
 272
 273         return sprintf(buf, "%u\n", chip->adc_bit);
 274 }
 275
 276 static ssize_t store_resolution(struct device *dev,
 277                 struct device_attribute *attr, const char *buf, size_t count)
 278 {
 279         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 280         struct isl29018_chip *chip = iio_priv(indio_dev);
 281         int status;
 282         unsigned long lval;
 283         unsigned int new_adc_bit;
 284
 285         if (strict_strtoul(buf, 10, &lval))
 286                 return -EINVAL;
 287         if (!(lval == 4 || lval == 8 || lval == 12 || lval == 16)) {
 288                 dev_err(dev, "The resolution is not supported\n");
 289                 return -EINVAL;
 290         }
 291
 292         mutex_lock(&chip->lock);
 293         status = isl29018_set_resolution(chip, lval, &new_adc_bit);
 294         if (status < 0) {
 295                 mutex_unlock(&chip->lock);
 296                 dev_err(dev, "Error in setting resolution\n");
 297                 return status;
 298         }
 299         chip->adc_bit = new_adc_bit;
 300         mutex_unlock(&chip->lock);
 301
 302         return count;
 303 }
 304
 305 /* proximity scheme */
 306 static ssize_t show_prox_infrared_suppression(struct device *dev,
 307                         struct device_attribute *attr, char *buf)
 308 {
 309         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 310         struct isl29018_chip *chip = iio_priv(indio_dev);
 311
 312         /* return the "proximity scheme" i.e. if the chip does on chip
 313         infrared suppression (1 means perform on chip suppression) */
 314         return sprintf(buf, "%d\n", chip->prox_scheme);
 315 }
 316
 317 static ssize_t store_prox_infrared_suppression(struct device *dev,
 318                 struct device_attribute *attr, const char *buf, size_t count)
 319 {
 320         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 321         struct isl29018_chip *chip = iio_priv(indio_dev);
 322         unsigned long lval;
 323
 324         if (strict_strtoul(buf, 10, &lval))
 325                 return -EINVAL;
 326         if (!(lval == 0UL || lval == 1UL)) {
 327                 dev_err(dev, "The mode is not supported\n");
 328                 return -EINVAL;
 329         }
 330
 331         /* get the  "proximity scheme" i.e. if the chip does on chip
 332         infrared suppression (1 means perform on chip suppression) */
 333         mutex_lock(&chip->lock);
 334         chip->prox_scheme = (int)lval;
 335         mutex_unlock(&chip->lock);
 336
 337         return count;
 338 }
 339
 340 /* Channel IO */
 341 static int isl29018_write_raw(struct iio_dev *indio_dev,
 342                               struct iio_chan_spec const *chan,
 343                               int val,
 344                               int val2,
 345                               long mask)
 346 {
 347         struct isl29018_chip *chip = iio_priv(indio_dev);
 348         int ret = -EINVAL;
 349
 350         mutex_lock(&chip->lock);
 351         if (mask == IIO_CHAN_INFO_CALIBSCALE && chan->type == IIO_LIGHT) {
 352                 chip->lux_scale = val;
 353                 /* With no write_raw_get_fmt(), val2 is a MICRO fraction. */
 354                 chip->lux_uscale = val2;
 355                 ret = 0;
 356         }
 357         mutex_unlock(&chip->lock);
 358
 359         return ret;
 360 }
 361
 362 static int isl29018_read_raw(struct iio_dev *indio_dev,
 363                              struct iio_chan_spec const *chan,
 364                              int *val,
 365                              int *val2,
 366                              long mask)
 367 {
 368         int ret = -EINVAL;
 369         struct isl29018_chip *chip = iio_priv(indio_dev);
 370
 371         mutex_lock(&chip->lock);
 372         if (chip->suspended) {
 373                 mutex_unlock(&chip->lock);
 374                 return -EBUSY;
 375         }
 376         switch (mask) {
 377         case IIO_CHAN_INFO_RAW:
 378         case IIO_CHAN_INFO_PROCESSED:
 379                 switch (chan->type) {
 380                 case IIO_LIGHT:
 381                         ret = isl29018_read_lux(chip, val);
 382                         break;
 383                 case IIO_INTENSITY:
 384                         ret = isl29018_read_ir(chip, val);
 385                         break;
 386                 case IIO_PROXIMITY:
 387                         ret = isl29018_read_proximity_ir(chip,
 388                                         chip->prox_scheme, val);
 389                         break;
 390                 default:
 391                         break;
 392                 }
 393                 if (!ret)
 394                         ret = IIO_VAL_INT;
 395                 break;
 396         case IIO_CHAN_INFO_CALIBSCALE:
 397                 if (chan->type == IIO_LIGHT) {
 398                         *val = chip->lux_scale;
 399                         *val2 = chip->lux_uscale;
 400                         ret = IIO_VAL_INT_PLUS_MICRO;
 401                 }
 402                 break;
 403         default:
 404                 break;
 405         }
 406         mutex_unlock(&chip->lock);
 407         return ret;
 408 }
 409
 410 static const struct iio_chan_spec isl29018_channels[] = {
 411         {
 412                 .type = IIO_LIGHT,
 413                 .indexed = 1,
 414                 .channel = 0,
 415                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 416                 BIT(IIO_CHAN_INFO_CALIBSCALE),
 417         }, {
 418                 .type = IIO_INTENSITY,
 419                 .modified = 1,
 420                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 421                 .channel2 = IIO_MOD_LIGHT_IR,
 422         }, {
 423                 /* Unindexed in current ABI.  But perhaps it should be. */
 424                 .type = IIO_PROXIMITY,
 425                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 426         }
 427 };
 428
 429 static IIO_DEVICE_ATTR(range, S_IRUGO | S_IWUSR, show_range, store_range, 0);
 430 static IIO_CONST_ATTR(range_available, "1000 4000 16000 64000");
 431 static IIO_CONST_ATTR(adc_resolution_available, "4 8 12 16");
 432 static IIO_DEVICE_ATTR(adc_resolution, S_IRUGO | S_IWUSR,
 433                                         show_resolution, store_resolution, 0);
 434 static IIO_DEVICE_ATTR(proximity_on_chip_ambient_infrared_suppression,
 435                                         S_IRUGO | S_IWUSR,
 436                                         show_prox_infrared_suppression,
 437                                         store_prox_infrared_suppression, 0);
 438
 439 #define ISL29018_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
 440 #define ISL29018_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
 441 static struct attribute *isl29018_attributes[] = {
 442         ISL29018_DEV_ATTR(range),
 443         ISL29018_CONST_ATTR(range_available),
 444         ISL29018_DEV_ATTR(adc_resolution),
 445         ISL29018_CONST_ATTR(adc_resolution_available),
 446         ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_suppression),
 447         NULL
 448 };
 449
 450 static const struct attribute_group isl29108_group = {
 451         .attrs = isl29018_attributes,
 452 };
 453
 454 static int isl29018_chip_init(struct isl29018_chip *chip)
 455 {
 456         int status;
 457         int new_adc_bit;
 458         unsigned int new_range;
 459
 460         /* Code added per Intersil Application Note 1534:
 461          *     When VDD sinks to approximately 1.8V or below, some of
 462          * the part's registers may change their state. When VDD
 463          * recovers to 2.25V (or greater), the part may thus be in an
 464          * unknown mode of operation. The user can return the part to
 465          * a known mode of operation either by (a) setting VDD = 0V for
 466          * 1 second or more and then powering back up with a slew rate
 467          * of 0.5V/ms or greater, or (b) via I2C disable all ALS/PROX
 468          * conversions, clear the test registers, and then rewrite all
 469          * registers to the desired values.
 470          * ...
 471          * FOR ISL29011, ISL29018, ISL29021, ISL29023
 472          * 1. Write 0x00 to register 0x08 (TEST)
 473          * 2. Write 0x00 to register 0x00 (CMD1)
 474          * 3. Rewrite all registers to the desired values
 475          *
 476          * ISL29018 Data Sheet (FN6619.1, Feb 11, 2010) essentially says
 477          * the same thing EXCEPT the data sheet asks for a 1ms delay after
 478          * writing the CMD1 register.
 479          */
 480         status = regmap_write(chip->regmap, ISL29018_REG_TEST, 0x0);
 481         if (status < 0) {
 482                 dev_err(chip->dev, "Failed to clear isl29018 TEST reg."
 483                                         "(%d)\n", status);
 484                 return status;
 485         }
 486
 487         /* See Intersil AN1534 comments above.
 488          * "Operating Mode" (COMMAND1) register is reprogrammed when
 489          * data is read from the device.
 490          */
 491         status = regmap_write(chip->regmap, ISL29018_REG_ADD_COMMAND1, 0);
 492         if (status < 0) {
 493                 dev_err(chip->dev, "Failed to clear isl29018 CMD1 reg."
 494                                         "(%d)\n", status);
 495                 return status;
 496         }
 497
 498         msleep(1);      /* per data sheet, page 10 */
 499
 500         /* set defaults */
 501         status = isl29018_set_range(chip, chip->range, &new_range);
 502         if (status < 0) {
 503                 dev_err(chip->dev, "Init of isl29018 fails\n");
 504                 return status;
 505         }
 506
 507         status = isl29018_set_resolution(chip, chip->adc_bit,
 508                                                 &new_adc_bit);
 509
 510         return 0;
 511 }
 512
 513 static const struct iio_info isl29108_info = {
 514         .attrs = &isl29108_group,
 515         .driver_module = THIS_MODULE,
 516         .read_raw = &isl29018_read_raw,
 517         .write_raw = &isl29018_write_raw,
 518 };
 519
 520 static bool is_volatile_reg(struct device *dev, unsigned int reg)
 521 {
 522         switch (reg) {
 523         case ISL29018_REG_ADD_DATA_LSB:
 524         case ISL29018_REG_ADD_DATA_MSB:
 525         case ISL29018_REG_ADD_COMMAND1:
 526         case ISL29018_REG_TEST:
 527                 return true;
 528         default:
 529                 return false;
 530         }
 531 }
 532
 533 /*
 534  * isl29018_regmap_config: regmap configuration.
 535  * Use RBTREE mechanism for caching.
 536  */
 537 static const struct regmap_config isl29018_regmap_config = {
 538         .reg_bits = 8,
 539         .val_bits = 8,
 540         .volatile_reg = is_volatile_reg,
 541         .max_register = ISL29018_REG_TEST,
 542         .num_reg_defaults_raw = ISL29018_REG_TEST + 1,
 543         .cache_type = REGCACHE_RBTREE,
 544 };
 545
 546 static int isl29018_probe(struct i2c_client *client,
 547                          const struct i2c_device_id *id)
 548 {
 549         struct isl29018_chip *chip;
 550         struct iio_dev *indio_dev;
 551         int err;
 552
 553         indio_dev = iio_device_alloc(sizeof(*chip));
 554         if (indio_dev == NULL) {
 555                 dev_err(&client->dev, "iio allocation fails\n");
 556                 err = -ENOMEM;
 557                 goto exit;
 558         }
 559         chip = iio_priv(indio_dev);
 560
 561         i2c_set_clientdata(client, indio_dev);
 562         chip->dev = &client->dev;
 563
 564         mutex_init(&chip->lock);
 565
 566         chip->lux_scale = 1;
 567         chip->range = 1000;
 568         chip->adc_bit = 16;
 569         chip->suspended = false;
 570
 571         chip->regmap = devm_regmap_init_i2c(client, &isl29018_regmap_config);
 572         if (IS_ERR(chip->regmap)) {
 573                 err = PTR_ERR(chip->regmap);
 574                 dev_err(chip->dev, "regmap initialization failed: %d\n", err);
 575                 goto exit;
 576         }
 577
 578         err = isl29018_chip_init(chip);
 579         if (err)
 580                 goto exit_iio_free;
 581
 582         indio_dev->info = &isl29108_info;
 583         indio_dev->channels = isl29018_channels;
 584         indio_dev->num_channels = ARRAY_SIZE(isl29018_channels);
 585         indio_dev->name = id->name;
 586         indio_dev->dev.parent = &client->dev;
 587         indio_dev->modes = INDIO_DIRECT_MODE;
 588         err = iio_device_register(indio_dev);
 589         if (err) {
 590                 dev_err(&client->dev, "iio registration fails\n");
 591                 goto exit_iio_free;
 592         }
 593
 594         return 0;
 595 exit_iio_free:
 596         iio_device_free(indio_dev);
 597 exit:
 598         return err;
 599 }
 600
 601 static int isl29018_remove(struct i2c_client *client)
 602 {
 603         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 604
 605         dev_dbg(&client->dev, "%s()\n", __func__);
 606         iio_device_unregister(indio_dev);
 607         iio_device_free(indio_dev);
 608
 609         return 0;
 610 }
 611
 612 #ifdef CONFIG_PM_SLEEP
 613 static int isl29018_suspend(struct device *dev)
 614 {
 615         struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
 616
 617         mutex_lock(&chip->lock);
 618
 619         /* Since this driver uses only polling commands, we are by default in
 620          * auto shutdown (ie, power-down) mode.
 621          * So we do not have much to do here.
 622          */
 623         chip->suspended = true;
 624
 625         mutex_unlock(&chip->lock);
 626         return 0;
 627 }
 628
 629 static int isl29018_resume(struct device *dev)
 630 {
 631         struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
 632         int err;
 633
 634         mutex_lock(&chip->lock);
 635
 636         err = isl29018_chip_init(chip);
 637         if (!err)
 638                 chip->suspended = false;
 639
 640         mutex_unlock(&chip->lock);
 641         return err;
 642 }
 643
 644 static SIMPLE_DEV_PM_OPS(isl29018_pm_ops, isl29018_suspend, isl29018_resume);
 645 #define ISL29018_PM_OPS (&isl29018_pm_ops)
 646 #else
 647 #define ISL29018_PM_OPS NULL
 648 #endif
 649
 650 static const struct i2c_device_id isl29018_id[] = {
 651         {"isl29018", 0},
 652         {}
 653 };
 654
 655 MODULE_DEVICE_TABLE(i2c, isl29018_id);
 656
 657 static const struct of_device_id isl29018_of_match[] = {
 658         { .compatible = "isil,isl29018", },
 659         { },
 660 };
 661 MODULE_DEVICE_TABLE(of, isl29018_of_match);
 662
 663 static struct i2c_driver isl29018_driver = {
 664         .class  = I2C_CLASS_HWMON,
 665         .driver  = {
 666                         .name = "isl29018",
 667                         .pm = ISL29018_PM_OPS,
 668                         .owner = THIS_MODULE,
 669                         .of_match_table = isl29018_of_match,
 670                     },
 671         .probe   = isl29018_probe,
 672         .remove  = isl29018_remove,
 673         .id_table = isl29018_id,
 674 };
 675 module_i2c_driver(isl29018_driver);
 676
 677 MODULE_DESCRIPTION("ISL29018 Ambient Light Sensor driver");
 678 MODULE_LICENSE("GPL");