drivers/iio/pressure/st_pressure_core.c

   1 /*
   2  * STMicroelectronics pressures driver
   3  *
   4  * Copyright 2013 STMicroelectronics Inc.
   5  *
   6  * Denis Ciocca <denis.ciocca@st.com>
   7  *
   8  * Licensed under the GPL-2.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/errno.h>
  15 #include <linux/types.h>
  16 #include <linux/mutex.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/i2c.h>
  19 #include <linux/gpio.h>
  20 #include <linux/irq.h>
  21 #include <linux/delay.h>
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/sysfs.h>
  24 #include <linux/iio/trigger.h>
  25 #include <linux/iio/buffer.h>
  26 #include <asm/unaligned.h>
  27
  28 #include <linux/iio/common/st_sensors.h>
  29 #include "st_pressure.h"
  30
  31 /*
  32  * About determining pressure scaling factors
  33  * ------------------------------------------
  34  *
  35  * Datasheets specify typical pressure sensitivity so that pressure is computed
  36  * according to the following equation :
  37  *     pressure[mBar] = raw / sensitivity
  38  * where :
  39  *     raw          the 24 bits long raw sampled pressure
  40  *     sensitivity  a scaling factor specified by the datasheet in LSB/mBar
  41  *
  42  * IIO ABI expects pressure to be expressed as kPascal, hence pressure should be
  43  * computed according to :
  44  *     pressure[kPascal] = pressure[mBar] / 10
  45  *                       = raw / (sensitivity * 10)                          (1)
  46  *
  47  * Finally, st_press_read_raw() returns pressure scaling factor as an
  48  * IIO_VAL_INT_PLUS_NANO with a zero integral part and "gain" as decimal part.
  49  * Therefore, from (1), "gain" becomes :
  50  *     gain = 10^9 / (sensitivity * 10)
  51  *          = 10^8 / sensitivity
  52  *
  53  * About determining temperature scaling factors and offsets
  54  * ---------------------------------------------------------
  55  *
  56  * Datasheets specify typical temperature sensitivity and offset so that
  57  * temperature is computed according to the following equation :
  58  *     temp[Celsius] = offset[Celsius] + (raw / sensitivity)
  59  * where :
  60  *     raw          the 16 bits long raw sampled temperature
  61  *     offset       a constant specified by the datasheet in degree Celsius
  62  *                  (sometimes zero)
  63  *     sensitivity  a scaling factor specified by the datasheet in LSB/Celsius
  64  *
  65  * IIO ABI expects temperature to be expressed as milli degree Celsius such as
  66  * user space should compute temperature according to :
  67  *     temp[mCelsius] = temp[Celsius] * 10^3
  68  *                    = (offset[Celsius] + (raw / sensitivity)) * 10^3
  69  *                    = ((offset[Celsius] * sensitivity) + raw) *
  70  *                      (10^3 / sensitivity)                                 (2)
  71  *
  72  * IIO ABI expects user space to apply offset and scaling factors to raw samples
  73  * according to :
  74  *     temp[mCelsius] = (OFFSET + raw) * SCALE
  75  * where :
  76  *     OFFSET an arbitrary constant exposed by device
  77  *     SCALE  an arbitrary scaling factor exposed by device
  78  *
  79  * Matching OFFSET and SCALE with members of (2) gives :
  80  *     OFFSET = offset[Celsius] * sensitivity                                (3)
  81  *     SCALE  = 10^3 / sensitivity                                           (4)
  82  *
  83  * st_press_read_raw() returns temperature scaling factor as an
  84  * IIO_VAL_FRACTIONAL with a 10^3 numerator and "gain2" as denominator.
  85  * Therefore, from (3), "gain2" becomes :
  86  *     gain2 = sensitivity
  87  *
  88  * When declared within channel, i.e. for a non zero specified offset,
  89  * st_press_read_raw() will return the latter as an IIO_VAL_FRACTIONAL such as :
  90  *     numerator = OFFSET * 10^3
  91  *     denominator = 10^3
  92  * giving from (4):
  93  *     numerator = offset[Celsius] * 10^3 * sensitivity
  94  *               = offset[mCelsius] * gain2
  95  */
  96
  97 #define MCELSIUS_PER_CELSIUS                    1000
  98
  99 /* Default pressure sensitivity */
 100 #define ST_PRESS_LSB_PER_MBAR                   4096UL
 101 #define ST_PRESS_KPASCAL_NANO_SCALE             (100000000UL / \
 102                                                  ST_PRESS_LSB_PER_MBAR)
 103
 104 /* Default temperature sensitivity */
 105 #define ST_PRESS_LSB_PER_CELSIUS                480UL
 106 #define ST_PRESS_MILLI_CELSIUS_OFFSET           42500UL
 107
 108 /* FULLSCALE */
 109 #define ST_PRESS_FS_AVL_1100MB                  1100
 110 #define ST_PRESS_FS_AVL_1260MB                  1260
 111
 112 #define ST_PRESS_1_OUT_XL_ADDR                  0x28
 113 #define ST_TEMP_1_OUT_L_ADDR                    0x2b
 114
 115 /* LPS001WP pressure resolution */
 116 #define ST_PRESS_LPS001WP_LSB_PER_MBAR          16UL
 117 /* LPS001WP temperature resolution */
 118 #define ST_PRESS_LPS001WP_LSB_PER_CELSIUS       64UL
 119 /* LPS001WP pressure gain */
 120 #define ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN \
 121         (100000000UL / ST_PRESS_LPS001WP_LSB_PER_MBAR)
 122 /* LPS001WP pressure and temp L addresses */
 123 #define ST_PRESS_LPS001WP_OUT_L_ADDR            0x28
 124 #define ST_TEMP_LPS001WP_OUT_L_ADDR             0x2a
 125
 126 /* LPS25H pressure and temp L addresses */
 127 #define ST_PRESS_LPS25H_OUT_XL_ADDR             0x28
 128 #define ST_TEMP_LPS25H_OUT_L_ADDR               0x2b
 129
 130 /* LPS22HB temperature sensitivity */
 131 #define ST_PRESS_LPS22HB_LSB_PER_CELSIUS        100UL
 132
 133 static const struct iio_chan_spec st_press_1_channels[] = {
 134         {
 135                 .type = IIO_PRESSURE,
 136                 .address = ST_PRESS_1_OUT_XL_ADDR,
 137                 .scan_index = 0,
 138                 .scan_type = {
 139                         .sign = 's',
 140                         .realbits = 24,
 141                         .storagebits = 32,
 142                         .endianness = IIO_LE,
 143                 },
 144                 .info_mask_separate =
 145                         BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
 146                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 147         },
 148         {
 149                 .type = IIO_TEMP,
 150                 .address = ST_TEMP_1_OUT_L_ADDR,
 151                 .scan_index = 1,
 152                 .scan_type = {
 153                         .sign = 's',
 154                         .realbits = 16,
 155                         .storagebits = 16,
 156                         .endianness = IIO_LE,
 157                 },
 158                 .info_mask_separate =
 159                         BIT(IIO_CHAN_INFO_RAW) |
 160                         BIT(IIO_CHAN_INFO_SCALE) |
 161                         BIT(IIO_CHAN_INFO_OFFSET),
 162                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 163         },
 164         IIO_CHAN_SOFT_TIMESTAMP(2)
 165 };
 166
 167 static const struct iio_chan_spec st_press_lps001wp_channels[] = {
 168         {
 169                 .type = IIO_PRESSURE,
 170                 .address = ST_PRESS_LPS001WP_OUT_L_ADDR,
 171                 .scan_index = 0,
 172                 .scan_type = {
 173                         .sign = 's',
 174                         .realbits = 16,
 175                         .storagebits = 16,
 176                         .endianness = IIO_LE,
 177                 },
 178                 .info_mask_separate =
 179                         BIT(IIO_CHAN_INFO_RAW) |
 180                         BIT(IIO_CHAN_INFO_SCALE),
 181         },
 182         {
 183                 .type = IIO_TEMP,
 184                 .address = ST_TEMP_LPS001WP_OUT_L_ADDR,
 185                 .scan_index = 1,
 186                 .scan_type = {
 187                         .sign = 's',
 188                         .realbits = 16,
 189                         .storagebits = 16,
 190                         .endianness = IIO_LE,
 191                 },
 192                 .info_mask_separate =
 193                         BIT(IIO_CHAN_INFO_RAW) |
 194                         BIT(IIO_CHAN_INFO_SCALE),
 195         },
 196         IIO_CHAN_SOFT_TIMESTAMP(2)
 197 };
 198
 199 static const struct iio_chan_spec st_press_lps22hb_channels[] = {
 200         {
 201                 .type = IIO_PRESSURE,
 202                 .address = ST_PRESS_1_OUT_XL_ADDR,
 203                 .scan_index = 0,
 204                 .scan_type = {
 205                         .sign = 's',
 206                         .realbits = 24,
 207                         .storagebits = 32,
 208                         .endianness = IIO_LE,
 209                 },
 210                 .info_mask_separate =
 211                         BIT(IIO_CHAN_INFO_RAW) |
 212                         BIT(IIO_CHAN_INFO_SCALE),
 213                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 214         },
 215         {
 216                 .type = IIO_TEMP,
 217                 .address = ST_TEMP_1_OUT_L_ADDR,
 218                 .scan_index = 1,
 219                 .scan_type = {
 220                         .sign = 's',
 221                         .realbits = 16,
 222                         .storagebits = 16,
 223                         .endianness = IIO_LE,
 224                 },
 225                 .info_mask_separate =
 226                         BIT(IIO_CHAN_INFO_RAW) |
 227                         BIT(IIO_CHAN_INFO_SCALE),
 228                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 229         },
 230         IIO_CHAN_SOFT_TIMESTAMP(2)
 231 };
 232
 233 static const struct st_sensor_settings st_press_sensors_settings[] = {
 234         {
 235                 /*
 236                  * CUSTOM VALUES FOR LPS331AP SENSOR
 237                  * See LPS331AP datasheet:
 238                  * http://www2.st.com/resource/en/datasheet/lps331ap.pdf
 239                  */
 240                 .wai = 0xbb,
 241                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 242                 .sensors_supported = {
 243                         [0] = LPS331AP_PRESS_DEV_NAME,
 244                 },
 245                 .ch = (struct iio_chan_spec *)st_press_1_channels,
 246                 .num_ch = ARRAY_SIZE(st_press_1_channels),
 247                 .odr = {
 248                         .addr = 0x20,
 249                         .mask = 0x70,
 250                         .odr_avl = {
 251                                 { .hz = 1, .value = 0x01 },
 252                                 { .hz = 7, .value = 0x05 },
 253                                 { .hz = 13, .value = 0x06 },
 254                                 { .hz = 25, .value = 0x07 },
 255                         },
 256                 },
 257                 .pw = {
 258                         .addr = 0x20,
 259                         .mask = 0x80,
 260                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 261                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 262                 },
 263                 .fs = {
 264                         .addr = 0x23,
 265                         .mask = 0x30,
 266                         .fs_avl = {
 267                                 /*
 268                                  * Pressure and temperature sensitivity values
 269                                  * as defined in table 3 of LPS331AP datasheet.
 270                                  */
 271                                 [0] = {
 272                                         .num = ST_PRESS_FS_AVL_1260MB,
 273                                         .gain = ST_PRESS_KPASCAL_NANO_SCALE,
 274                                         .gain2 = ST_PRESS_LSB_PER_CELSIUS,
 275                                 },
 276                         },
 277                 },
 278                 .bdu = {
 279                         .addr = 0x20,
 280                         .mask = 0x04,
 281                 },
 282                 .drdy_irq = {
 283                         .addr = 0x22,
 284                         .mask_int1 = 0x04,
 285                         .mask_int2 = 0x20,
 286                         .addr_ihl = 0x22,
 287                         .mask_ihl = 0x80,
 288                         .addr_od = 0x22,
 289                         .mask_od = 0x40,
 290                         .stat_drdy = {
 291                                 .addr = ST_SENSORS_DEFAULT_STAT_ADDR,
 292                                 .mask = 0x03,
 293                         },
 294                 },
 295                 .multi_read_bit = true,
 296                 .bootime = 2,
 297         },
 298         {
 299                 /*
 300                  * CUSTOM VALUES FOR LPS001WP SENSOR
 301                  */
 302                 .wai = 0xba,
 303                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 304                 .sensors_supported = {
 305                         [0] = LPS001WP_PRESS_DEV_NAME,
 306                 },
 307                 .ch = (struct iio_chan_spec *)st_press_lps001wp_channels,
 308                 .num_ch = ARRAY_SIZE(st_press_lps001wp_channels),
 309                 .odr = {
 310                         .addr = 0x20,
 311                         .mask = 0x30,
 312                         .odr_avl = {
 313                                 { .hz = 1, .value = 0x01 },
 314                                 { .hz = 7, .value = 0x02 },
 315                                 { .hz = 13, .value = 0x03 },
 316                         },
 317                 },
 318                 .pw = {
 319                         .addr = 0x20,
 320                         .mask = 0x40,
 321                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 322                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 323                 },
 324                 .fs = {
 325                         .fs_avl = {
 326                                 /*
 327                                  * Pressure and temperature resolution values
 328                                  * as defined in table 3 of LPS001WP datasheet.
 329                                  */
 330                                 [0] = {
 331                                         .num = ST_PRESS_FS_AVL_1100MB,
 332                                         .gain = ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN,
 333                                         .gain2 = ST_PRESS_LPS001WP_LSB_PER_CELSIUS,
 334                                 },
 335                         },
 336                 },
 337                 .bdu = {
 338                         .addr = 0x20,
 339                         .mask = 0x04,
 340                 },
 341                 .drdy_irq = {
 342                         .addr = 0,
 343                 },
 344                 .multi_read_bit = true,
 345                 .bootime = 2,
 346         },
 347         {
 348                 /*
 349                  * CUSTOM VALUES FOR LPS25H SENSOR
 350                  * See LPS25H datasheet:
 351                  * http://www2.st.com/resource/en/datasheet/lps25h.pdf
 352                  */
 353                 .wai = 0xbd,
 354                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 355                 .sensors_supported = {
 356                         [0] = LPS25H_PRESS_DEV_NAME,
 357                 },
 358                 .ch = (struct iio_chan_spec *)st_press_1_channels,
 359                 .num_ch = ARRAY_SIZE(st_press_1_channels),
 360                 .odr = {
 361                         .addr = 0x20,
 362                         .mask = 0x70,
 363                         .odr_avl = {
 364                                 { .hz = 1, .value = 0x01 },
 365                                 { .hz = 7, .value = 0x02 },
 366                                 { .hz = 13, .value = 0x03 },
 367                                 { .hz = 25, .value = 0x04 },
 368                         },
 369                 },
 370                 .pw = {
 371                         .addr = 0x20,
 372                         .mask = 0x80,
 373                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 374                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 375                 },
 376                 .fs = {
 377                         .fs_avl = {
 378                                 /*
 379                                  * Pressure and temperature sensitivity values
 380                                  * as defined in table 3 of LPS25H datasheet.
 381                                  */
 382                                 [0] = {
 383                                         .num = ST_PRESS_FS_AVL_1260MB,
 384                                         .gain = ST_PRESS_KPASCAL_NANO_SCALE,
 385                                         .gain2 = ST_PRESS_LSB_PER_CELSIUS,
 386                                 },
 387                         },
 388                 },
 389                 .bdu = {
 390                         .addr = 0x20,
 391                         .mask = 0x04,
 392                 },
 393                 .drdy_irq = {
 394                         .addr = 0x23,
 395                         .mask_int1 = 0x01,
 396                         .mask_int2 = 0x00,
 397                         .addr_ihl = 0x22,
 398                         .mask_ihl = 0x80,
 399                         .addr_od = 0x22,
 400                         .mask_od = 0x40,
 401                         .stat_drdy = {
 402                                 .addr = ST_SENSORS_DEFAULT_STAT_ADDR,
 403                                 .mask = 0x03,
 404                         },
 405                 },
 406                 .multi_read_bit = true,
 407                 .bootime = 2,
 408         },
 409         {
 410                 /*
 411                  * CUSTOM VALUES FOR LPS22HB SENSOR
 412                  * See LPS22HB datasheet:
 413                  * http://www2.st.com/resource/en/datasheet/lps22hb.pdf
 414                  */
 415                 .wai = 0xb1,
 416                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 417                 .sensors_supported = {
 418                         [0] = LPS22HB_PRESS_DEV_NAME,
 419                 },
 420                 .ch = (struct iio_chan_spec *)st_press_lps22hb_channels,
 421                 .num_ch = ARRAY_SIZE(st_press_lps22hb_channels),
 422                 .odr = {
 423                         .addr = 0x10,
 424                         .mask = 0x70,
 425                         .odr_avl = {
 426                                 { .hz = 1, .value = 0x01 },
 427                                 { .hz = 10, .value = 0x02 },
 428                                 { .hz = 25, .value = 0x03 },
 429                                 { .hz = 50, .value = 0x04 },
 430                                 { .hz = 75, .value = 0x05 },
 431                         },
 432                 },
 433                 .pw = {
 434                         .addr = 0x10,
 435                         .mask = 0x70,
 436                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 437                 },
 438                 .fs = {
 439                         .fs_avl = {
 440                                 /*
 441                                  * Pressure and temperature sensitivity values
 442                                  * as defined in table 3 of LPS22HB datasheet.
 443                                  */
 444                                 [0] = {
 445                                         .num = ST_PRESS_FS_AVL_1260MB,
 446                                         .gain = ST_PRESS_KPASCAL_NANO_SCALE,
 447                                         .gain2 = ST_PRESS_LPS22HB_LSB_PER_CELSIUS,
 448                                 },
 449                         },
 450                 },
 451                 .bdu = {
 452                         .addr = 0x10,
 453                         .mask = 0x02,
 454                 },
 455                 .drdy_irq = {
 456                         .addr = 0x12,
 457                         .mask_int1 = 0x04,
 458                         .mask_int2 = 0x00,
 459                         .addr_ihl = 0x12,
 460                         .mask_ihl = 0x80,
 461                         .addr_od = 0x12,
 462                         .mask_od = 0x40,
 463                         .stat_drdy = {
 464                                 .addr = ST_SENSORS_DEFAULT_STAT_ADDR,
 465                                 .mask = 0x03,
 466                         },
 467                 },
 468                 .multi_read_bit = false,
 469                 .bootime = 2,
 470         },
 471 };
 472
 473 static int st_press_write_raw(struct iio_dev *indio_dev,
 474                               struct iio_chan_spec const *ch,
 475                               int val,
 476                               int val2,
 477                               long mask)
 478 {
 479         int err;
 480
 481         switch (mask) {
 482         case IIO_CHAN_INFO_SAMP_FREQ:
 483                 if (val2)
 484                         return -EINVAL;
 485                 mutex_lock(&indio_dev->mlock);
 486                 err = st_sensors_set_odr(indio_dev, val);
 487                 mutex_unlock(&indio_dev->mlock);
 488                 return err;
 489         default:
 490                 return -EINVAL;
 491         }
 492 }
 493
 494 static int st_press_read_raw(struct iio_dev *indio_dev,
 495                         struct iio_chan_spec const *ch, int *val,
 496                                                         int *val2, long mask)
 497 {
 498         int err;
 499         struct st_sensor_data *press_data = iio_priv(indio_dev);
 500
 501         switch (mask) {
 502         case IIO_CHAN_INFO_RAW:
 503                 err = st_sensors_read_info_raw(indio_dev, ch, val);
 504                 if (err < 0)
 505                         goto read_error;
 506
 507                 return IIO_VAL_INT;
 508         case IIO_CHAN_INFO_SCALE:
 509                 switch (ch->type) {
 510                 case IIO_PRESSURE:
 511                         *val = 0;
 512                         *val2 = press_data->current_fullscale->gain;
 513                         return IIO_VAL_INT_PLUS_NANO;
 514                 case IIO_TEMP:
 515                         *val = MCELSIUS_PER_CELSIUS;
 516                         *val2 = press_data->current_fullscale->gain2;
 517                         return IIO_VAL_FRACTIONAL;
 518                 default:
 519                         err = -EINVAL;
 520                         goto read_error;
 521                 }
 522
 523         case IIO_CHAN_INFO_OFFSET:
 524                 switch (ch->type) {
 525                 case IIO_TEMP:
 526                         *val = ST_PRESS_MILLI_CELSIUS_OFFSET *
 527                                press_data->current_fullscale->gain2;
 528                         *val2 = MCELSIUS_PER_CELSIUS;
 529                         break;
 530                 default:
 531                         err = -EINVAL;
 532                         goto read_error;
 533                 }
 534
 535                 return IIO_VAL_FRACTIONAL;
 536         case IIO_CHAN_INFO_SAMP_FREQ:
 537                 *val = press_data->odr;
 538                 return IIO_VAL_INT;
 539         default:
 540                 return -EINVAL;
 541         }
 542
 543 read_error:
 544         return err;
 545 }
 546
 547 static ST_SENSORS_DEV_ATTR_SAMP_FREQ_AVAIL();
 548
 549 static struct attribute *st_press_attributes[] = {
 550         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 551         NULL,
 552 };
 553
 554 static const struct attribute_group st_press_attribute_group = {
 555         .attrs = st_press_attributes,
 556 };
 557
 558 static const struct iio_info press_info = {
 559         .driver_module = THIS_MODULE,
 560         .attrs = &st_press_attribute_group,
 561         .read_raw = &st_press_read_raw,
 562         .write_raw = &st_press_write_raw,
 563         .debugfs_reg_access = &st_sensors_debugfs_reg_access,
 564 };
 565
 566 #ifdef CONFIG_IIO_TRIGGER
 567 static const struct iio_trigger_ops st_press_trigger_ops = {
 568         .owner = THIS_MODULE,
 569         .set_trigger_state = ST_PRESS_TRIGGER_SET_STATE,
 570         .validate_device = st_sensors_validate_device,
 571 };
 572 #define ST_PRESS_TRIGGER_OPS (&st_press_trigger_ops)
 573 #else
 574 #define ST_PRESS_TRIGGER_OPS NULL
 575 #endif
 576
 577 int st_press_common_probe(struct iio_dev *indio_dev)
 578 {
 579         struct st_sensor_data *press_data = iio_priv(indio_dev);
 580         struct st_sensors_platform_data *pdata =
 581                 (struct st_sensors_platform_data *)press_data->dev->platform_data;
 582         int irq = press_data->get_irq_data_ready(indio_dev);
 583         int err;
 584
 585         indio_dev->modes = INDIO_DIRECT_MODE;
 586         indio_dev->info = &press_info;
 587         mutex_init(&press_data->tb.buf_lock);
 588
 589         err = st_sensors_power_enable(indio_dev);
 590         if (err)
 591                 return err;
 592
 593         err = st_sensors_check_device_support(indio_dev,
 594                                         ARRAY_SIZE(st_press_sensors_settings),
 595                                         st_press_sensors_settings);
 596         if (err < 0)
 597                 goto st_press_power_off;
 598
 599         /*
 600          * Skip timestamping channel while declaring available channels to
 601          * common st_sensor layer. Look at st_sensors_get_buffer_element() to
 602          * see how timestamps are explicitly pushed as last samples block
 603          * element.
 604          */
 605         press_data->num_data_channels = press_data->sensor_settings->num_ch - 1;
 606         press_data->multiread_bit = press_data->sensor_settings->multi_read_bit;
 607         indio_dev->channels = press_data->sensor_settings->ch;
 608         indio_dev->num_channels = press_data->sensor_settings->num_ch;
 609
 610         press_data->current_fullscale =
 611                 (struct st_sensor_fullscale_avl *)
 612                         &press_data->sensor_settings->fs.fs_avl[0];
 613
 614         press_data->odr = press_data->sensor_settings->odr.odr_avl[0].hz;
 615
 616         /* Some devices don't support a data ready pin. */
 617         if (!pdata && press_data->sensor_settings->drdy_irq.addr)
 618                 pdata = (struct st_sensors_platform_data *)&default_press_pdata;
 619
 620         err = st_sensors_init_sensor(indio_dev, pdata);
 621         if (err < 0)
 622                 goto st_press_power_off;
 623
 624         err = st_press_allocate_ring(indio_dev);
 625         if (err < 0)
 626                 goto st_press_power_off;
 627
 628         if (irq > 0) {
 629                 err = st_sensors_allocate_trigger(indio_dev,
 630                                                   ST_PRESS_TRIGGER_OPS);
 631                 if (err < 0)
 632                         goto st_press_probe_trigger_error;
 633         }
 634
 635         err = iio_device_register(indio_dev);
 636         if (err)
 637                 goto st_press_device_register_error;
 638
 639         dev_info(&indio_dev->dev, "registered pressure sensor %s\n",
 640                  indio_dev->name);
 641
 642         return err;
 643
 644 st_press_device_register_error:
 645         if (irq > 0)
 646                 st_sensors_deallocate_trigger(indio_dev);
 647 st_press_probe_trigger_error:
 648         st_press_deallocate_ring(indio_dev);
 649 st_press_power_off:
 650         st_sensors_power_disable(indio_dev);
 651
 652         return err;
 653 }
 654 EXPORT_SYMBOL(st_press_common_probe);
 655
 656 void st_press_common_remove(struct iio_dev *indio_dev)
 657 {
 658         struct st_sensor_data *press_data = iio_priv(indio_dev);
 659
 660         st_sensors_power_disable(indio_dev);
 661
 662         iio_device_unregister(indio_dev);
 663         if (press_data->get_irq_data_ready(indio_dev) > 0)
 664                 st_sensors_deallocate_trigger(indio_dev);
 665
 666         st_press_deallocate_ring(indio_dev);
 667 }
 668 EXPORT_SYMBOL(st_press_common_remove);
 669
 670 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 671 MODULE_DESCRIPTION("STMicroelectronics pressures driver");
 672 MODULE_LICENSE("GPL v2");