kernel/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 #define MCELSIUS_PER_CELSIUS                    1000
  32
  33 /* Default pressure sensitivity */
  34 #define ST_PRESS_LSB_PER_MBAR                   4096UL
  35 #define ST_PRESS_KPASCAL_NANO_SCALE             (100000000UL / \
  36                                                  ST_PRESS_LSB_PER_MBAR)
  37
  38 /* Default temperature sensitivity */
  39 #define ST_PRESS_LSB_PER_CELSIUS                480UL
  40 #define ST_PRESS_MILLI_CELSIUS_OFFSET           42500UL
  41
  42 #define ST_PRESS_NUMBER_DATA_CHANNELS           1
  43
  44 /* FULLSCALE */
  45 #define ST_PRESS_FS_AVL_1100MB                  1100
  46 #define ST_PRESS_FS_AVL_1260MB                  1260
  47
  48 #define ST_PRESS_1_OUT_XL_ADDR                  0x28
  49 #define ST_TEMP_1_OUT_L_ADDR                    0x2b
  50
  51 /* CUSTOM VALUES FOR LPS331AP SENSOR */
  52 #define ST_PRESS_LPS331AP_WAI_EXP               0xbb
  53 #define ST_PRESS_LPS331AP_ODR_ADDR              0x20
  54 #define ST_PRESS_LPS331AP_ODR_MASK              0x70
  55 #define ST_PRESS_LPS331AP_ODR_AVL_1HZ_VAL       0x01
  56 #define ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL       0x05
  57 #define ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL      0x06
  58 #define ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL      0x07
  59 #define ST_PRESS_LPS331AP_PW_ADDR               0x20
  60 #define ST_PRESS_LPS331AP_PW_MASK               0x80
  61 #define ST_PRESS_LPS331AP_FS_ADDR               0x23
  62 #define ST_PRESS_LPS331AP_FS_MASK               0x30
  63 #define ST_PRESS_LPS331AP_BDU_ADDR              0x20
  64 #define ST_PRESS_LPS331AP_BDU_MASK              0x04
  65 #define ST_PRESS_LPS331AP_DRDY_IRQ_ADDR         0x22
  66 #define ST_PRESS_LPS331AP_DRDY_IRQ_INT1_MASK    0x04
  67 #define ST_PRESS_LPS331AP_DRDY_IRQ_INT2_MASK    0x20
  68 #define ST_PRESS_LPS331AP_MULTIREAD_BIT         true
  69
  70 /* CUSTOM VALUES FOR LPS001WP SENSOR */
  71
  72 /* LPS001WP pressure resolution */
  73 #define ST_PRESS_LPS001WP_LSB_PER_MBAR          16UL
  74 /* LPS001WP temperature resolution */
  75 #define ST_PRESS_LPS001WP_LSB_PER_CELSIUS       64UL
  76
  77 #define ST_PRESS_LPS001WP_WAI_EXP               0xba
  78 #define ST_PRESS_LPS001WP_ODR_ADDR              0x20
  79 #define ST_PRESS_LPS001WP_ODR_MASK              0x30
  80 #define ST_PRESS_LPS001WP_ODR_AVL_1HZ_VAL       0x01
  81 #define ST_PRESS_LPS001WP_ODR_AVL_7HZ_VAL       0x02
  82 #define ST_PRESS_LPS001WP_ODR_AVL_13HZ_VAL      0x03
  83 #define ST_PRESS_LPS001WP_PW_ADDR               0x20
  84 #define ST_PRESS_LPS001WP_PW_MASK               0x40
  85 #define ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN \
  86         (100000000UL / ST_PRESS_LPS001WP_LSB_PER_MBAR)
  87 #define ST_PRESS_LPS001WP_BDU_ADDR              0x20
  88 #define ST_PRESS_LPS001WP_BDU_MASK              0x04
  89 #define ST_PRESS_LPS001WP_MULTIREAD_BIT         true
  90 #define ST_PRESS_LPS001WP_OUT_L_ADDR            0x28
  91 #define ST_TEMP_LPS001WP_OUT_L_ADDR             0x2a
  92
  93 /* CUSTOM VALUES FOR LPS25H SENSOR */
  94 #define ST_PRESS_LPS25H_WAI_EXP                 0xbd
  95 #define ST_PRESS_LPS25H_ODR_ADDR                0x20
  96 #define ST_PRESS_LPS25H_ODR_MASK                0x70
  97 #define ST_PRESS_LPS25H_ODR_AVL_1HZ_VAL         0x01
  98 #define ST_PRESS_LPS25H_ODR_AVL_7HZ_VAL         0x02
  99 #define ST_PRESS_LPS25H_ODR_AVL_13HZ_VAL        0x03
 100 #define ST_PRESS_LPS25H_ODR_AVL_25HZ_VAL        0x04
 101 #define ST_PRESS_LPS25H_PW_ADDR                 0x20
 102 #define ST_PRESS_LPS25H_PW_MASK                 0x80
 103 #define ST_PRESS_LPS25H_BDU_ADDR                0x20
 104 #define ST_PRESS_LPS25H_BDU_MASK                0x04
 105 #define ST_PRESS_LPS25H_DRDY_IRQ_ADDR           0x23
 106 #define ST_PRESS_LPS25H_DRDY_IRQ_INT1_MASK      0x01
 107 #define ST_PRESS_LPS25H_DRDY_IRQ_INT2_MASK      0x10
 108 #define ST_PRESS_LPS25H_MULTIREAD_BIT           true
 109 #define ST_PRESS_LPS25H_OUT_XL_ADDR             0x28
 110 #define ST_TEMP_LPS25H_OUT_L_ADDR               0x2b
 111
 112 static const struct iio_chan_spec st_press_1_channels[] = {
 113         {
 114                 .type = IIO_PRESSURE,
 115                 .channel2 = IIO_NO_MOD,
 116                 .address = ST_PRESS_1_OUT_XL_ADDR,
 117                 .scan_index = ST_SENSORS_SCAN_X,
 118                 .scan_type = {
 119                         .sign = 'u',
 120                         .realbits = 24,
 121                         .storagebits = 24,
 122                         .endianness = IIO_LE,
 123                 },
 124                 .info_mask_separate =
 125                         BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
 126                 .modified = 0,
 127         },
 128         {
 129                 .type = IIO_TEMP,
 130                 .channel2 = IIO_NO_MOD,
 131                 .address = ST_TEMP_1_OUT_L_ADDR,
 132                 .scan_index = -1,
 133                 .scan_type = {
 134                         .sign = 'u',
 135                         .realbits = 16,
 136                         .storagebits = 16,
 137                         .endianness = IIO_LE,
 138                 },
 139                 .info_mask_separate =
 140                         BIT(IIO_CHAN_INFO_RAW) |
 141                         BIT(IIO_CHAN_INFO_SCALE) |
 142                         BIT(IIO_CHAN_INFO_OFFSET),
 143                 .modified = 0,
 144         },
 145         IIO_CHAN_SOFT_TIMESTAMP(1)
 146 };
 147
 148 static const struct iio_chan_spec st_press_lps001wp_channels[] = {
 149         {
 150                 .type = IIO_PRESSURE,
 151                 .channel2 = IIO_NO_MOD,
 152                 .address = ST_PRESS_LPS001WP_OUT_L_ADDR,
 153                 .scan_index = ST_SENSORS_SCAN_X,
 154                 .scan_type = {
 155                         .sign = 'u',
 156                         .realbits = 16,
 157                         .storagebits = 16,
 158                         .endianness = IIO_LE,
 159                 },
 160                 .info_mask_separate =
 161                         BIT(IIO_CHAN_INFO_RAW) |
 162                         BIT(IIO_CHAN_INFO_SCALE),
 163                 .modified = 0,
 164         },
 165         {
 166                 .type = IIO_TEMP,
 167                 .channel2 = IIO_NO_MOD,
 168                 .address = ST_TEMP_LPS001WP_OUT_L_ADDR,
 169                 .scan_index = -1,
 170                 .scan_type = {
 171                         .sign = 'u',
 172                         .realbits = 16,
 173                         .storagebits = 16,
 174                         .endianness = IIO_LE,
 175                 },
 176                 .info_mask_separate =
 177                         BIT(IIO_CHAN_INFO_RAW) |
 178                         BIT(IIO_CHAN_INFO_SCALE),
 179                 .modified = 0,
 180         },
 181         IIO_CHAN_SOFT_TIMESTAMP(1)
 182 };
 183
 184 static const struct st_sensor_settings st_press_sensors_settings[] = {
 185         {
 186                 .wai = ST_PRESS_LPS331AP_WAI_EXP,
 187                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 188                 .sensors_supported = {
 189                         [0] = LPS331AP_PRESS_DEV_NAME,
 190                 },
 191                 .ch = (struct iio_chan_spec *)st_press_1_channels,
 192                 .num_ch = ARRAY_SIZE(st_press_1_channels),
 193                 .odr = {
 194                         .addr = ST_PRESS_LPS331AP_ODR_ADDR,
 195                         .mask = ST_PRESS_LPS331AP_ODR_MASK,
 196                         .odr_avl = {
 197                                 { 1, ST_PRESS_LPS331AP_ODR_AVL_1HZ_VAL, },
 198                                 { 7, ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL, },
 199                                 { 13, ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL, },
 200                                 { 25, ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL, },
 201                         },
 202                 },
 203                 .pw = {
 204                         .addr = ST_PRESS_LPS331AP_PW_ADDR,
 205                         .mask = ST_PRESS_LPS331AP_PW_MASK,
 206                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 207                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 208                 },
 209                 .fs = {
 210                         .addr = ST_PRESS_LPS331AP_FS_ADDR,
 211                         .mask = ST_PRESS_LPS331AP_FS_MASK,
 212                         .fs_avl = {
 213                                 /*
 214                                  * Pressure and temperature sensitivity values
 215                                  * as defined in table 3 of LPS331AP datasheet.
 216                                  */
 217                                 [0] = {
 218                                         .num = ST_PRESS_FS_AVL_1260MB,
 219                                         .gain = ST_PRESS_KPASCAL_NANO_SCALE,
 220                                         .gain2 = ST_PRESS_LSB_PER_CELSIUS,
 221                                 },
 222                         },
 223                 },
 224                 .bdu = {
 225                         .addr = ST_PRESS_LPS331AP_BDU_ADDR,
 226                         .mask = ST_PRESS_LPS331AP_BDU_MASK,
 227                 },
 228                 .drdy_irq = {
 229                         .addr = ST_PRESS_LPS331AP_DRDY_IRQ_ADDR,
 230                         .mask_int1 = ST_PRESS_LPS331AP_DRDY_IRQ_INT1_MASK,
 231                         .mask_int2 = ST_PRESS_LPS331AP_DRDY_IRQ_INT2_MASK,
 232                 },
 233                 .multi_read_bit = ST_PRESS_LPS331AP_MULTIREAD_BIT,
 234                 .bootime = 2,
 235         },
 236         {
 237                 .wai = ST_PRESS_LPS001WP_WAI_EXP,
 238                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 239                 .sensors_supported = {
 240                         [0] = LPS001WP_PRESS_DEV_NAME,
 241                 },
 242                 .ch = (struct iio_chan_spec *)st_press_lps001wp_channels,
 243                 .num_ch = ARRAY_SIZE(st_press_lps001wp_channels),
 244                 .odr = {
 245                         .addr = ST_PRESS_LPS001WP_ODR_ADDR,
 246                         .mask = ST_PRESS_LPS001WP_ODR_MASK,
 247                         .odr_avl = {
 248                                 { 1, ST_PRESS_LPS001WP_ODR_AVL_1HZ_VAL, },
 249                                 { 7, ST_PRESS_LPS001WP_ODR_AVL_7HZ_VAL, },
 250                                 { 13, ST_PRESS_LPS001WP_ODR_AVL_13HZ_VAL, },
 251                         },
 252                 },
 253                 .pw = {
 254                         .addr = ST_PRESS_LPS001WP_PW_ADDR,
 255                         .mask = ST_PRESS_LPS001WP_PW_MASK,
 256                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 257                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 258                 },
 259                 .fs = {
 260                         .fs_avl = {
 261                                 /*
 262                                  * Pressure and temperature resolution values
 263                                  * as defined in table 3 of LPS001WP datasheet.
 264                                  */
 265                                 [0] = {
 266                                         .num = ST_PRESS_FS_AVL_1100MB,
 267                                         .gain = ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN,
 268                                         .gain2 = ST_PRESS_LPS001WP_LSB_PER_CELSIUS,
 269                                 },
 270                         },
 271                 },
 272                 .bdu = {
 273                         .addr = ST_PRESS_LPS001WP_BDU_ADDR,
 274                         .mask = ST_PRESS_LPS001WP_BDU_MASK,
 275                 },
 276                 .drdy_irq = {
 277                         .addr = 0,
 278                 },
 279                 .multi_read_bit = ST_PRESS_LPS001WP_MULTIREAD_BIT,
 280                 .bootime = 2,
 281         },
 282         {
 283                 .wai = ST_PRESS_LPS25H_WAI_EXP,
 284                 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 285                 .sensors_supported = {
 286                         [0] = LPS25H_PRESS_DEV_NAME,
 287                 },
 288                 .ch = (struct iio_chan_spec *)st_press_1_channels,
 289                 .num_ch = ARRAY_SIZE(st_press_1_channels),
 290                 .odr = {
 291                         .addr = ST_PRESS_LPS25H_ODR_ADDR,
 292                         .mask = ST_PRESS_LPS25H_ODR_MASK,
 293                         .odr_avl = {
 294                                 { 1, ST_PRESS_LPS25H_ODR_AVL_1HZ_VAL, },
 295                                 { 7, ST_PRESS_LPS25H_ODR_AVL_7HZ_VAL, },
 296                                 { 13, ST_PRESS_LPS25H_ODR_AVL_13HZ_VAL, },
 297                                 { 25, ST_PRESS_LPS25H_ODR_AVL_25HZ_VAL, },
 298                         },
 299                 },
 300                 .pw = {
 301                         .addr = ST_PRESS_LPS25H_PW_ADDR,
 302                         .mask = ST_PRESS_LPS25H_PW_MASK,
 303                         .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
 304                         .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
 305                 },
 306                 .fs = {
 307                         .fs_avl = {
 308                                 /*
 309                                  * Pressure and temperature sensitivity values
 310                                  * as defined in table 3 of LPS25H datasheet.
 311                                  */
 312                                 [0] = {
 313                                         .num = ST_PRESS_FS_AVL_1260MB,
 314                                         .gain = ST_PRESS_KPASCAL_NANO_SCALE,
 315                                         .gain2 = ST_PRESS_LSB_PER_CELSIUS,
 316                                 },
 317                         },
 318                 },
 319                 .bdu = {
 320                         .addr = ST_PRESS_LPS25H_BDU_ADDR,
 321                         .mask = ST_PRESS_LPS25H_BDU_MASK,
 322                 },
 323                 .drdy_irq = {
 324                         .addr = ST_PRESS_LPS25H_DRDY_IRQ_ADDR,
 325                         .mask_int1 = ST_PRESS_LPS25H_DRDY_IRQ_INT1_MASK,
 326                         .mask_int2 = ST_PRESS_LPS25H_DRDY_IRQ_INT2_MASK,
 327                 },
 328                 .multi_read_bit = ST_PRESS_LPS25H_MULTIREAD_BIT,
 329                 .bootime = 2,
 330         },
 331 };
 332
 333 static int st_press_write_raw(struct iio_dev *indio_dev,
 334                               struct iio_chan_spec const *ch,
 335                               int val,
 336                               int val2,
 337                               long mask)
 338 {
 339         int err;
 340
 341         switch (mask) {
 342         case IIO_CHAN_INFO_SAMP_FREQ:
 343                 if (val2)
 344                         return -EINVAL;
 345                 mutex_lock(&indio_dev->mlock);
 346                 err = st_sensors_set_odr(indio_dev, val);
 347                 mutex_unlock(&indio_dev->mlock);
 348                 return err;
 349         default:
 350                 return -EINVAL;
 351         }
 352 }
 353
 354 static int st_press_read_raw(struct iio_dev *indio_dev,
 355                         struct iio_chan_spec const *ch, int *val,
 356                                                         int *val2, long mask)
 357 {
 358         int err;
 359         struct st_sensor_data *press_data = iio_priv(indio_dev);
 360
 361         switch (mask) {
 362         case IIO_CHAN_INFO_RAW:
 363                 err = st_sensors_read_info_raw(indio_dev, ch, val);
 364                 if (err < 0)
 365                         goto read_error;
 366
 367                 return IIO_VAL_INT;
 368         case IIO_CHAN_INFO_SCALE:
 369                 switch (ch->type) {
 370                 case IIO_PRESSURE:
 371                         *val = 0;
 372                         *val2 = press_data->current_fullscale->gain;
 373                         return IIO_VAL_INT_PLUS_NANO;
 374                 case IIO_TEMP:
 375                         *val = MCELSIUS_PER_CELSIUS;
 376                         *val2 = press_data->current_fullscale->gain2;
 377                         return IIO_VAL_FRACTIONAL;
 378                 default:
 379                         err = -EINVAL;
 380                         goto read_error;
 381                 }
 382
 383         case IIO_CHAN_INFO_OFFSET:
 384                 switch (ch->type) {
 385                 case IIO_TEMP:
 386                         *val = ST_PRESS_MILLI_CELSIUS_OFFSET *
 387                                press_data->current_fullscale->gain2;
 388                         *val2 = MCELSIUS_PER_CELSIUS;
 389                         break;
 390                 default:
 391                         err = -EINVAL;
 392                         goto read_error;
 393                 }
 394
 395                 return IIO_VAL_FRACTIONAL;
 396         case IIO_CHAN_INFO_SAMP_FREQ:
 397                 *val = press_data->odr;
 398                 return IIO_VAL_INT;
 399         default:
 400                 return -EINVAL;
 401         }
 402
 403 read_error:
 404         return err;
 405 }
 406
 407 static ST_SENSORS_DEV_ATTR_SAMP_FREQ_AVAIL();
 408
 409 static struct attribute *st_press_attributes[] = {
 410         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 411         NULL,
 412 };
 413
 414 static const struct attribute_group st_press_attribute_group = {
 415         .attrs = st_press_attributes,
 416 };
 417
 418 static const struct iio_info press_info = {
 419         .driver_module = THIS_MODULE,
 420         .attrs = &st_press_attribute_group,
 421         .read_raw = &st_press_read_raw,
 422         .write_raw = &st_press_write_raw,
 423         .debugfs_reg_access = &st_sensors_debugfs_reg_access,
 424 };
 425
 426 #ifdef CONFIG_IIO_TRIGGER
 427 static const struct iio_trigger_ops st_press_trigger_ops = {
 428         .owner = THIS_MODULE,
 429         .set_trigger_state = ST_PRESS_TRIGGER_SET_STATE,
 430 };
 431 #define ST_PRESS_TRIGGER_OPS (&st_press_trigger_ops)
 432 #else
 433 #define ST_PRESS_TRIGGER_OPS NULL
 434 #endif
 435
 436 int st_press_common_probe(struct iio_dev *indio_dev)
 437 {
 438         struct st_sensor_data *press_data = iio_priv(indio_dev);
 439         int irq = press_data->get_irq_data_ready(indio_dev);
 440         int err;
 441
 442         indio_dev->modes = INDIO_DIRECT_MODE;
 443         indio_dev->info = &press_info;
 444         mutex_init(&press_data->tb.buf_lock);
 445
 446         st_sensors_power_enable(indio_dev);
 447
 448         err = st_sensors_check_device_support(indio_dev,
 449                                         ARRAY_SIZE(st_press_sensors_settings),
 450                                         st_press_sensors_settings);
 451         if (err < 0)
 452                 return err;
 453
 454         press_data->num_data_channels = ST_PRESS_NUMBER_DATA_CHANNELS;
 455         press_data->multiread_bit = press_data->sensor_settings->multi_read_bit;
 456         indio_dev->channels = press_data->sensor_settings->ch;
 457         indio_dev->num_channels = press_data->sensor_settings->num_ch;
 458
 459         if (press_data->sensor_settings->fs.addr != 0)
 460                 press_data->current_fullscale =
 461                         (struct st_sensor_fullscale_avl *)
 462                                 &press_data->sensor_settings->fs.fs_avl[0];
 463
 464         press_data->odr = press_data->sensor_settings->odr.odr_avl[0].hz;
 465
 466         /* Some devices don't support a data ready pin. */
 467         if (!press_data->dev->platform_data &&
 468                                 press_data->sensor_settings->drdy_irq.addr)
 469                 press_data->dev->platform_data =
 470                         (struct st_sensors_platform_data *)&default_press_pdata;
 471
 472         err = st_sensors_init_sensor(indio_dev, press_data->dev->platform_data);
 473         if (err < 0)
 474                 return err;
 475
 476         err = st_press_allocate_ring(indio_dev);
 477         if (err < 0)
 478                 return err;
 479
 480         if (irq > 0) {
 481                 err = st_sensors_allocate_trigger(indio_dev,
 482                                                   ST_PRESS_TRIGGER_OPS);
 483                 if (err < 0)
 484                         goto st_press_probe_trigger_error;
 485         }
 486
 487         err = iio_device_register(indio_dev);
 488         if (err)
 489                 goto st_press_device_register_error;
 490
 491         dev_info(&indio_dev->dev, "registered pressure sensor %s\n",
 492                  indio_dev->name);
 493
 494         return err;
 495
 496 st_press_device_register_error:
 497         if (irq > 0)
 498                 st_sensors_deallocate_trigger(indio_dev);
 499 st_press_probe_trigger_error:
 500         st_press_deallocate_ring(indio_dev);
 501
 502         return err;
 503 }
 504 EXPORT_SYMBOL(st_press_common_probe);
 505
 506 void st_press_common_remove(struct iio_dev *indio_dev)
 507 {
 508         struct st_sensor_data *press_data = iio_priv(indio_dev);
 509
 510         st_sensors_power_disable(indio_dev);
 511
 512         iio_device_unregister(indio_dev);
 513         if (press_data->get_irq_data_ready(indio_dev) > 0)
 514                 st_sensors_deallocate_trigger(indio_dev);
 515
 516         st_press_deallocate_ring(indio_dev);
 517 }
 518 EXPORT_SYMBOL(st_press_common_remove);
 519
 520 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 521 MODULE_DESCRIPTION("STMicroelectronics pressures driver");
 522 MODULE_LICENSE("GPL v2");