drivers/iio/chemical/scd30_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Sensirion SCD30 carbon dioxide sensor core driver
   4  *
   5  * Copyright (c) 2020 Tomasz Duszynski <tomasz.duszynski@octakon.com>
   6  */
   7 #include <linux/bits.h>
   8 #include <linux/completion.h>
   9 #include <linux/delay.h>
  10 #include <linux/device.h>
  11 #include <linux/errno.h>
  12 #include <linux/export.h>
  13 #include <linux/iio/buffer.h>
  14 #include <linux/iio/iio.h>
  15 #include <linux/iio/sysfs.h>
  16 #include <linux/iio/trigger.h>
  17 #include <linux/iio/trigger_consumer.h>
  18 #include <linux/iio/triggered_buffer.h>
  19 #include <linux/iio/types.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/irqreturn.h>
  22 #include <linux/jiffies.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/mutex.h>
  26 #include <linux/regulator/consumer.h>
  27 #include <linux/string.h>
  28 #include <linux/sysfs.h>
  29 #include <linux/types.h>
  30 #include <asm/byteorder.h>
  31
  32 #include "scd30.h"
  33
  34 #define SCD30_PRESSURE_COMP_MIN_MBAR 700
  35 #define SCD30_PRESSURE_COMP_MAX_MBAR 1400
  36 #define SCD30_PRESSURE_COMP_DEFAULT 1013
  37 #define SCD30_MEAS_INTERVAL_MIN_S 2
  38 #define SCD30_MEAS_INTERVAL_MAX_S 1800
  39 #define SCD30_MEAS_INTERVAL_DEFAULT SCD30_MEAS_INTERVAL_MIN_S
  40 #define SCD30_FRC_MIN_PPM 400
  41 #define SCD30_FRC_MAX_PPM 2000
  42 #define SCD30_TEMP_OFFSET_MAX 655360
  43 #define SCD30_EXTRA_TIMEOUT_PER_S 250
  44
  45 enum {
  46         SCD30_CONC,
  47         SCD30_TEMP,
  48         SCD30_HR,
  49 };
  50
  51 static int scd30_command_write(struct scd30_state *state, enum scd30_cmd cmd, u16 arg)
  52 {
  53         return state->command(state, cmd, arg, NULL, 0);
  54 }
  55
  56 static int scd30_command_read(struct scd30_state *state, enum scd30_cmd cmd, u16 *val)
  57 {
  58         __be16 tmp;
  59         int ret;
  60
  61         ret = state->command(state, cmd, 0, &tmp, sizeof(tmp));
  62         *val = be16_to_cpup(&tmp);
  63
  64         return ret;
  65 }
  66
  67 static int scd30_reset(struct scd30_state *state)
  68 {
  69         int ret;
  70         u16 val;
  71
  72         ret = scd30_command_write(state, CMD_RESET, 0);
  73         if (ret)
  74                 return ret;
  75
  76         /* sensor boots up within 2 secs */
  77         msleep(2000);
  78         /*
  79          * Power-on-reset causes sensor to produce some glitch on i2c bus and
  80          * some controllers end up in error state. Try to recover by placing
  81          * any data on the bus.
  82          */
  83         scd30_command_read(state, CMD_MEAS_READY, &val);
  84
  85         return 0;
  86 }
  87
  88 /* simplified float to fixed point conversion with a scaling factor of 0.01 */
  89 static int scd30_float_to_fp(int float32)
  90 {
  91         int fraction, shift,
  92             mantissa = float32 & GENMASK(22, 0),
  93             sign = (float32 & BIT(31)) ? -1 : 1,
  94             exp = (float32 & ~BIT(31)) >> 23;
  95
  96         /* special case 0 */
  97         if (!exp && !mantissa)
  98                 return 0;
  99
 100         exp -= 127;
 101         if (exp < 0) {
 102                 exp = -exp;
 103                 /* return values ranging from 1 to 99 */
 104                 return sign * ((((BIT(23) + mantissa) * 100) >> 23) >> exp);
 105         }
 106
 107         /* return values starting at 100 */
 108         shift = 23 - exp;
 109         float32 = BIT(exp) + (mantissa >> shift);
 110         fraction = mantissa & GENMASK(shift - 1, 0);
 111
 112         return sign * (float32 * 100 + ((fraction * 100) >> shift));
 113 }
 114
 115 static int scd30_read_meas(struct scd30_state *state)
 116 {
 117         int i, ret;
 118
 119         ret = state->command(state, CMD_READ_MEAS, 0, state->meas, sizeof(state->meas));
 120         if (ret)
 121                 return ret;
 122
 123         be32_to_cpu_array(state->meas, (__be32 *)state->meas, ARRAY_SIZE(state->meas));
 124
 125         for (i = 0; i < ARRAY_SIZE(state->meas); i++)
 126                 state->meas[i] = scd30_float_to_fp(state->meas[i]);
 127
 128         /*
 129          * co2 is left unprocessed while temperature and humidity are scaled
 130          * to milli deg C and milli percent respectively.
 131          */
 132         state->meas[SCD30_TEMP] *= 10;
 133         state->meas[SCD30_HR] *= 10;
 134
 135         return 0;
 136 }
 137
 138 static int scd30_wait_meas_irq(struct scd30_state *state)
 139 {
 140         int ret, timeout;
 141
 142         reinit_completion(&state->meas_ready);
 143         enable_irq(state->irq);
 144         timeout = msecs_to_jiffies(state->meas_interval * (1000 + SCD30_EXTRA_TIMEOUT_PER_S));
 145         ret = wait_for_completion_interruptible_timeout(&state->meas_ready, timeout);
 146         if (ret > 0)
 147                 ret = 0;
 148         else if (!ret)
 149                 ret = -ETIMEDOUT;
 150
 151         disable_irq(state->irq);
 152
 153         return ret;
 154 }
 155
 156 static int scd30_wait_meas_poll(struct scd30_state *state)
 157 {
 158         int timeout = state->meas_interval * SCD30_EXTRA_TIMEOUT_PER_S, tries = 5;
 159
 160         do {
 161                 int ret;
 162                 u16 val;
 163
 164                 ret = scd30_command_read(state, CMD_MEAS_READY, &val);
 165                 if (ret)
 166                         return -EIO;
 167
 168                 /* new measurement available */
 169                 if (val)
 170                         break;
 171
 172                 msleep_interruptible(timeout);
 173         } while (--tries);
 174
 175         return tries ? 0 : -ETIMEDOUT;
 176 }
 177
 178 static int scd30_read_poll(struct scd30_state *state)
 179 {
 180         int ret;
 181
 182         ret = scd30_wait_meas_poll(state);
 183         if (ret)
 184                 return ret;
 185
 186         return scd30_read_meas(state);
 187 }
 188
 189 static int scd30_read(struct scd30_state *state)
 190 {
 191         if (state->irq > 0)
 192                 return scd30_wait_meas_irq(state);
 193
 194         return scd30_read_poll(state);
 195 }
 196
 197 static int scd30_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
 198                           int *val, int *val2, long mask)
 199 {
 200         struct scd30_state *state = iio_priv(indio_dev);
 201         int ret = -EINVAL;
 202         u16 tmp;
 203
 204         mutex_lock(&state->lock);
 205         switch (mask) {
 206         case IIO_CHAN_INFO_RAW:
 207         case IIO_CHAN_INFO_PROCESSED:
 208                 if (chan->output) {
 209                         *val = state->pressure_comp;
 210                         ret = IIO_VAL_INT;
 211                         break;
 212                 }
 213
 214                 ret = iio_device_claim_direct_mode(indio_dev);
 215                 if (ret)
 216                         break;
 217
 218                 ret = scd30_read(state);
 219                 if (ret) {
 220                         iio_device_release_direct_mode(indio_dev);
 221                         break;
 222                 }
 223
 224                 *val = state->meas[chan->address];
 225                 iio_device_release_direct_mode(indio_dev);
 226                 ret = IIO_VAL_INT;
 227                 break;
 228         case IIO_CHAN_INFO_SCALE:
 229                 *val = 0;
 230                 *val2 = 1;
 231                 ret = IIO_VAL_INT_PLUS_MICRO;
 232                 break;
 233         case IIO_CHAN_INFO_SAMP_FREQ:
 234                 ret = scd30_command_read(state, CMD_MEAS_INTERVAL, &tmp);
 235                 if (ret)
 236                         break;
 237
 238                 *val = 0;
 239                 *val2 = 1000000000 / tmp;
 240                 ret = IIO_VAL_INT_PLUS_NANO;
 241                 break;
 242         case IIO_CHAN_INFO_CALIBBIAS:
 243                 ret = scd30_command_read(state, CMD_TEMP_OFFSET, &tmp);
 244                 if (ret)
 245                         break;
 246
 247                 *val = tmp;
 248                 ret = IIO_VAL_INT;
 249                 break;
 250         }
 251         mutex_unlock(&state->lock);
 252
 253         return ret;
 254 }
 255
 256 static int scd30_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
 257                            int val, int val2, long mask)
 258 {
 259         struct scd30_state *state = iio_priv(indio_dev);
 260         int ret = -EINVAL;
 261
 262         mutex_lock(&state->lock);
 263         switch (mask) {
 264         case IIO_CHAN_INFO_SAMP_FREQ:
 265                 if (val)
 266                         break;
 267
 268                 val = 1000000000 / val2;
 269                 if (val < SCD30_MEAS_INTERVAL_MIN_S || val > SCD30_MEAS_INTERVAL_MAX_S)
 270                         break;
 271
 272                 ret = scd30_command_write(state, CMD_MEAS_INTERVAL, val);
 273                 if (ret)
 274                         break;
 275
 276                 state->meas_interval = val;
 277                 break;
 278         case IIO_CHAN_INFO_RAW:
 279                 switch (chan->type) {
 280                 case IIO_PRESSURE:
 281                         if (val < SCD30_PRESSURE_COMP_MIN_MBAR ||
 282                             val > SCD30_PRESSURE_COMP_MAX_MBAR)
 283                                 break;
 284
 285                         ret = scd30_command_write(state, CMD_START_MEAS, val);
 286                         if (ret)
 287                                 break;
 288
 289                         state->pressure_comp = val;
 290                         break;
 291                 default:
 292                         break;
 293                 }
 294                 break;
 295         case IIO_CHAN_INFO_CALIBBIAS:
 296                 if (val < 0 || val > SCD30_TEMP_OFFSET_MAX)
 297                         break;
 298                 /*
 299                  * Manufacturer does not explicitly specify min/max sensible
 300                  * values hence check is omitted for simplicity.
 301                  */
 302                 ret = scd30_command_write(state, CMD_TEMP_OFFSET / 10, val);
 303         }
 304         mutex_unlock(&state->lock);
 305
 306         return ret;
 307 }
 308
 309 static int scd30_write_raw_get_fmt(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
 310                                    long mask)
 311 {
 312         switch (mask) {
 313         case IIO_CHAN_INFO_SAMP_FREQ:
 314                 return IIO_VAL_INT_PLUS_NANO;
 315         case IIO_CHAN_INFO_RAW:
 316         case IIO_CHAN_INFO_CALIBBIAS:
 317                 return IIO_VAL_INT;
 318         }
 319
 320         return -EINVAL;
 321 }
 322
 323 static const int scd30_pressure_raw_available[] = {
 324         SCD30_PRESSURE_COMP_MIN_MBAR, 1, SCD30_PRESSURE_COMP_MAX_MBAR,
 325 };
 326
 327 static const int scd30_temp_calibbias_available[] = {
 328         0, 10, SCD30_TEMP_OFFSET_MAX,
 329 };
 330
 331 static int scd30_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
 332                             const int **vals, int *type, int *length, long mask)
 333 {
 334         switch (mask) {
 335         case IIO_CHAN_INFO_RAW:
 336                 *vals = scd30_pressure_raw_available;
 337                 *type = IIO_VAL_INT;
 338
 339                 return IIO_AVAIL_RANGE;
 340         case IIO_CHAN_INFO_CALIBBIAS:
 341                 *vals = scd30_temp_calibbias_available;
 342                 *type = IIO_VAL_INT;
 343
 344                 return IIO_AVAIL_RANGE;
 345         }
 346
 347         return -EINVAL;
 348 }
 349
 350 static ssize_t sampling_frequency_available_show(struct device *dev, struct device_attribute *attr,
 351                                                  char *buf)
 352 {
 353         int i = SCD30_MEAS_INTERVAL_MIN_S;
 354         ssize_t len = 0;
 355
 356         do {
 357                 len += sysfs_emit_at(buf, len, "0.%09u ", 1000000000 / i);
 358                 /*
 359                  * Not all values fit PAGE_SIZE buffer hence print every 6th
 360                  * (each frequency differs by 6s in time domain from the
 361                  * adjacent). Unlisted but valid ones are still accepted.
 362                  */
 363                 i += 6;
 364         } while (i <= SCD30_MEAS_INTERVAL_MAX_S);
 365
 366         buf[len - 1] = '\n';
 367
 368         return len;
 369 }
 370
 371 static ssize_t calibration_auto_enable_show(struct device *dev, struct device_attribute *attr,
 372                                             char *buf)
 373 {
 374         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 375         struct scd30_state *state = iio_priv(indio_dev);
 376         int ret;
 377         u16 val;
 378
 379         mutex_lock(&state->lock);
 380         ret = scd30_command_read(state, CMD_ASC, &val);
 381         mutex_unlock(&state->lock);
 382
 383         return ret ?: sysfs_emit(buf, "%d\n", val);
 384 }
 385
 386 static ssize_t calibration_auto_enable_store(struct device *dev, struct device_attribute *attr,
 387                                              const char *buf, size_t len)
 388 {
 389         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 390         struct scd30_state *state = iio_priv(indio_dev);
 391         bool val;
 392         int ret;
 393
 394         ret = kstrtobool(buf, &val);
 395         if (ret)
 396                 return ret;
 397
 398         mutex_lock(&state->lock);
 399         ret = scd30_command_write(state, CMD_ASC, val);
 400         mutex_unlock(&state->lock);
 401
 402         return ret ?: len;
 403 }
 404
 405 static ssize_t calibration_forced_value_show(struct device *dev, struct device_attribute *attr,
 406                                              char *buf)
 407 {
 408         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 409         struct scd30_state *state = iio_priv(indio_dev);
 410         int ret;
 411         u16 val;
 412
 413         mutex_lock(&state->lock);
 414         ret = scd30_command_read(state, CMD_FRC, &val);
 415         mutex_unlock(&state->lock);
 416
 417         return ret ?: sysfs_emit(buf, "%d\n", val);
 418 }
 419
 420 static ssize_t calibration_forced_value_store(struct device *dev, struct device_attribute *attr,
 421                                               const char *buf, size_t len)
 422 {
 423         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 424         struct scd30_state *state = iio_priv(indio_dev);
 425         int ret;
 426         u16 val;
 427
 428         ret = kstrtou16(buf, 0, &val);
 429         if (ret)
 430                 return ret;
 431
 432         if (val < SCD30_FRC_MIN_PPM || val > SCD30_FRC_MAX_PPM)
 433                 return -EINVAL;
 434
 435         mutex_lock(&state->lock);
 436         ret = scd30_command_write(state, CMD_FRC, val);
 437         mutex_unlock(&state->lock);
 438
 439         return ret ?: len;
 440 }
 441
 442 static IIO_DEVICE_ATTR_RO(sampling_frequency_available, 0);
 443 static IIO_DEVICE_ATTR_RW(calibration_auto_enable, 0);
 444 static IIO_DEVICE_ATTR_RW(calibration_forced_value, 0);
 445
 446 static struct attribute *scd30_attrs[] = {
 447         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 448         &iio_dev_attr_calibration_auto_enable.dev_attr.attr,
 449         &iio_dev_attr_calibration_forced_value.dev_attr.attr,
 450         NULL
 451 };
 452
 453 static const struct attribute_group scd30_attr_group = {
 454         .attrs = scd30_attrs,
 455 };
 456
 457 static const struct iio_info scd30_info = {
 458         .attrs = &scd30_attr_group,
 459         .read_raw = scd30_read_raw,
 460         .write_raw = scd30_write_raw,
 461         .write_raw_get_fmt = scd30_write_raw_get_fmt,
 462         .read_avail = scd30_read_avail,
 463 };
 464
 465 #define SCD30_CHAN_SCAN_TYPE(_sign, _realbits) .scan_type = { \
 466         .sign = _sign, \
 467         .realbits = _realbits, \
 468         .storagebits = 32, \
 469         .endianness = IIO_CPU, \
 470 }
 471
 472 static const struct iio_chan_spec scd30_channels[] = {
 473         {
 474                 /*
 475                  * this channel is special in a sense we are pretending that
 476                  * sensor is able to change measurement chamber pressure but in
 477                  * fact we're just setting pressure compensation value
 478                  */
 479                 .type = IIO_PRESSURE,
 480                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 481                 .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW),
 482                 .output = 1,
 483                 .scan_index = -1,
 484         },
 485         {
 486                 .type = IIO_CONCENTRATION,
 487                 .channel2 = IIO_MOD_CO2,
 488                 .address = SCD30_CONC,
 489                 .scan_index = SCD30_CONC,
 490                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 491                                       BIT(IIO_CHAN_INFO_SCALE),
 492                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 493                 .modified = 1,
 494
 495                 SCD30_CHAN_SCAN_TYPE('u', 20),
 496         },
 497         {
 498                 .type = IIO_TEMP,
 499                 .address = SCD30_TEMP,
 500                 .scan_index = SCD30_TEMP,
 501                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 502                                       BIT(IIO_CHAN_INFO_CALIBBIAS),
 503                 .info_mask_separate_available = BIT(IIO_CHAN_INFO_CALIBBIAS),
 504                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 505
 506                 SCD30_CHAN_SCAN_TYPE('s', 18),
 507         },
 508         {
 509                 .type = IIO_HUMIDITYRELATIVE,
 510                 .address = SCD30_HR,
 511                 .scan_index = SCD30_HR,
 512                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
 513                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 514
 515                 SCD30_CHAN_SCAN_TYPE('u', 17),
 516         },
 517         IIO_CHAN_SOFT_TIMESTAMP(3),
 518 };
 519
 520 static int scd30_suspend(struct device *dev)
 521 {
 522         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 523         struct scd30_state *state  = iio_priv(indio_dev);
 524         int ret;
 525
 526         ret = scd30_command_write(state, CMD_STOP_MEAS, 0);
 527         if (ret)
 528                 return ret;
 529
 530         return regulator_disable(state->vdd);
 531 }
 532
 533 static int scd30_resume(struct device *dev)
 534 {
 535         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 536         struct scd30_state *state = iio_priv(indio_dev);
 537         int ret;
 538
 539         ret = regulator_enable(state->vdd);
 540         if (ret)
 541                 return ret;
 542
 543         return scd30_command_write(state, CMD_START_MEAS, state->pressure_comp);
 544 }
 545
 546 EXPORT_NS_SIMPLE_DEV_PM_OPS(scd30_pm_ops, scd30_suspend, scd30_resume, IIO_SCD30);
 547
 548 static void scd30_stop_meas(void *data)
 549 {
 550         struct scd30_state *state = data;
 551
 552         scd30_command_write(state, CMD_STOP_MEAS, 0);
 553 }
 554
 555 static void scd30_disable_regulator(void *data)
 556 {
 557         struct scd30_state *state = data;
 558
 559         regulator_disable(state->vdd);
 560 }
 561
 562 static irqreturn_t scd30_irq_handler(int irq, void *priv)
 563 {
 564         struct iio_dev *indio_dev = priv;
 565
 566         if (iio_buffer_enabled(indio_dev)) {
 567                 iio_trigger_poll(indio_dev->trig);
 568
 569                 return IRQ_HANDLED;
 570         }
 571
 572         return IRQ_WAKE_THREAD;
 573 }
 574
 575 static irqreturn_t scd30_irq_thread_handler(int irq, void *priv)
 576 {
 577         struct iio_dev *indio_dev = priv;
 578         struct scd30_state *state = iio_priv(indio_dev);
 579         int ret;
 580
 581         ret = scd30_read_meas(state);
 582         if (ret)
 583                 goto out;
 584
 585         complete_all(&state->meas_ready);
 586 out:
 587         return IRQ_HANDLED;
 588 }
 589
 590 static irqreturn_t scd30_trigger_handler(int irq, void *p)
 591 {
 592         struct iio_poll_func *pf = p;
 593         struct iio_dev *indio_dev = pf->indio_dev;
 594         struct scd30_state *state = iio_priv(indio_dev);
 595         struct {
 596                 int data[SCD30_MEAS_COUNT];
 597                 s64 ts __aligned(8);
 598         } scan;
 599         int ret;
 600
 601         mutex_lock(&state->lock);
 602         if (!iio_trigger_using_own(indio_dev))
 603                 ret = scd30_read_poll(state);
 604         else
 605                 ret = scd30_read_meas(state);
 606         memset(&scan, 0, sizeof(scan));
 607         memcpy(scan.data, state->meas, sizeof(state->meas));
 608         mutex_unlock(&state->lock);
 609         if (ret)
 610                 goto out;
 611
 612         iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
 613 out:
 614         iio_trigger_notify_done(indio_dev->trig);
 615         return IRQ_HANDLED;
 616 }
 617
 618 static int scd30_set_trigger_state(struct iio_trigger *trig, bool state)
 619 {
 620         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 621         struct scd30_state *st = iio_priv(indio_dev);
 622
 623         if (state)
 624                 enable_irq(st->irq);
 625         else
 626                 disable_irq(st->irq);
 627
 628         return 0;
 629 }
 630
 631 static const struct iio_trigger_ops scd30_trigger_ops = {
 632         .set_trigger_state = scd30_set_trigger_state,
 633         .validate_device = iio_trigger_validate_own_device,
 634 };
 635
 636 static int scd30_setup_trigger(struct iio_dev *indio_dev)
 637 {
 638         struct scd30_state *state = iio_priv(indio_dev);
 639         struct device *dev = indio_dev->dev.parent;
 640         struct iio_trigger *trig;
 641         int ret;
 642
 643         trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
 644                                       iio_device_id(indio_dev));
 645         if (!trig)
 646                 return dev_err_probe(dev, -ENOMEM, "failed to allocate trigger\n");
 647
 648         trig->ops = &scd30_trigger_ops;
 649         iio_trigger_set_drvdata(trig, indio_dev);
 650
 651         ret = devm_iio_trigger_register(dev, trig);
 652         if (ret)
 653                 return ret;
 654
 655         indio_dev->trig = iio_trigger_get(trig);
 656
 657         /*
 658          * Interrupt is enabled just before taking a fresh measurement
 659          * and disabled afterwards. This means we need to ensure it is not
 660          * enabled here to keep calls to enable/disable balanced.
 661          */
 662         ret = devm_request_threaded_irq(dev, state->irq, scd30_irq_handler,
 663                                         scd30_irq_thread_handler,
 664                                         IRQF_TRIGGER_HIGH | IRQF_ONESHOT |
 665                                         IRQF_NO_AUTOEN,
 666                                         indio_dev->name, indio_dev);
 667         if (ret)
 668                 return dev_err_probe(dev, ret, "failed to request irq\n");
 669
 670         return 0;
 671 }
 672
 673 int scd30_probe(struct device *dev, int irq, const char *name, void *priv,
 674                 scd30_command_t command)
 675 {
 676         static const unsigned long scd30_scan_masks[] = { 0x07, 0x00 };
 677         struct scd30_state *state;
 678         struct iio_dev *indio_dev;
 679         int ret;
 680         u16 val;
 681
 682         indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
 683         if (!indio_dev)
 684                 return -ENOMEM;
 685
 686         state = iio_priv(indio_dev);
 687         state->dev = dev;
 688         state->priv = priv;
 689         state->irq = irq;
 690         state->pressure_comp = SCD30_PRESSURE_COMP_DEFAULT;
 691         state->meas_interval = SCD30_MEAS_INTERVAL_DEFAULT;
 692         state->command = command;
 693         mutex_init(&state->lock);
 694         init_completion(&state->meas_ready);
 695
 696         dev_set_drvdata(dev, indio_dev);
 697
 698         indio_dev->info = &scd30_info;
 699         indio_dev->name = name;
 700         indio_dev->channels = scd30_channels;
 701         indio_dev->num_channels = ARRAY_SIZE(scd30_channels);
 702         indio_dev->modes = INDIO_DIRECT_MODE;
 703         indio_dev->available_scan_masks = scd30_scan_masks;
 704
 705         state->vdd = devm_regulator_get(dev, "vdd");
 706         if (IS_ERR(state->vdd))
 707                 return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
 708
 709         ret = regulator_enable(state->vdd);
 710         if (ret)
 711                 return ret;
 712
 713         ret = devm_add_action_or_reset(dev, scd30_disable_regulator, state);
 714         if (ret)
 715                 return ret;
 716
 717         ret = scd30_reset(state);
 718         if (ret)
 719                 return dev_err_probe(dev, ret, "failed to reset device\n");
 720
 721         if (state->irq > 0) {
 722                 ret = scd30_setup_trigger(indio_dev);
 723                 if (ret)
 724                         return dev_err_probe(dev, ret, "failed to setup trigger\n");
 725         }
 726
 727         ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd30_trigger_handler, NULL);
 728         if (ret)
 729                 return ret;
 730
 731         ret = scd30_command_read(state, CMD_FW_VERSION, &val);
 732         if (ret)
 733                 return dev_err_probe(dev, ret, "failed to read firmware version\n");
 734         dev_info(dev, "firmware version: %d.%d\n", val >> 8, (char)val);
 735
 736         ret = scd30_command_write(state, CMD_MEAS_INTERVAL, state->meas_interval);
 737         if (ret)
 738                 return dev_err_probe(dev, ret, "failed to set measurement interval\n");
 739
 740         ret = scd30_command_write(state, CMD_START_MEAS, state->pressure_comp);
 741         if (ret)
 742                 return dev_err_probe(dev, ret, "failed to start measurement\n");
 743
 744         ret = devm_add_action_or_reset(dev, scd30_stop_meas, state);
 745         if (ret)
 746                 return ret;
 747
 748         return devm_iio_device_register(dev, indio_dev);
 749 }
 750 EXPORT_SYMBOL_NS(scd30_probe, "IIO_SCD30");
 751
 752 MODULE_AUTHOR("Tomasz Duszynski <tomasz.duszynski@octakon.com>");
 753 MODULE_DESCRIPTION("Sensirion SCD30 carbon dioxide sensor core driver");
 754 MODULE_LICENSE("GPL v2");