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 .addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR, 291 }, 292 .multi_read_bit = true, 293 .bootime = 2, 294 }, 295 { 296 /* 297 * CUSTOM VALUES FOR LPS001WP SENSOR 298 */ 299 .wai = 0xba, 300 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, 301 .sensors_supported = { 302 [0] = LPS001WP_PRESS_DEV_NAME, 303 }, 304 .ch = (struct iio_chan_spec *)st_press_lps001wp_channels, 305 .num_ch = ARRAY_SIZE(st_press_lps001wp_channels), 306 .odr = { 307 .addr = 0x20, 308 .mask = 0x30, 309 .odr_avl = { 310 { .hz = 1, .value = 0x01 }, 311 { .hz = 7, .value = 0x02 }, 312 { .hz = 13, .value = 0x03 }, 313 }, 314 }, 315 .pw = { 316 .addr = 0x20, 317 .mask = 0x40, 318 .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE, 319 .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, 320 }, 321 .fs = { 322 .fs_avl = { 323 /* 324 * Pressure and temperature resolution values 325 * as defined in table 3 of LPS001WP datasheet. 326 */ 327 [0] = { 328 .num = ST_PRESS_FS_AVL_1100MB, 329 .gain = ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN, 330 .gain2 = ST_PRESS_LPS001WP_LSB_PER_CELSIUS, 331 }, 332 }, 333 }, 334 .bdu = { 335 .addr = 0x20, 336 .mask = 0x04, 337 }, 338 .drdy_irq = { 339 .addr = 0, 340 }, 341 .multi_read_bit = true, 342 .bootime = 2, 343 }, 344 { 345 /* 346 * CUSTOM VALUES FOR LPS25H SENSOR 347 * See LPS25H datasheet: 348 * http://www2.st.com/resource/en/datasheet/lps25h.pdf 349 */ 350 .wai = 0xbd, 351 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, 352 .sensors_supported = { 353 [0] = LPS25H_PRESS_DEV_NAME, 354 }, 355 .ch = (struct iio_chan_spec *)st_press_1_channels, 356 .num_ch = ARRAY_SIZE(st_press_1_channels), 357 .odr = { 358 .addr = 0x20, 359 .mask = 0x70, 360 .odr_avl = { 361 { .hz = 1, .value = 0x01 }, 362 { .hz = 7, .value = 0x02 }, 363 { .hz = 13, .value = 0x03 }, 364 { .hz = 25, .value = 0x04 }, 365 }, 366 }, 367 .pw = { 368 .addr = 0x20, 369 .mask = 0x80, 370 .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE, 371 .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, 372 }, 373 .fs = { 374 .fs_avl = { 375 /* 376 * Pressure and temperature sensitivity values 377 * as defined in table 3 of LPS25H datasheet. 378 */ 379 [0] = { 380 .num = ST_PRESS_FS_AVL_1260MB, 381 .gain = ST_PRESS_KPASCAL_NANO_SCALE, 382 .gain2 = ST_PRESS_LSB_PER_CELSIUS, 383 }, 384 }, 385 }, 386 .bdu = { 387 .addr = 0x20, 388 .mask = 0x04, 389 }, 390 .drdy_irq = { 391 .addr = 0x23, 392 .mask_int1 = 0x01, 393 .mask_int2 = 0x10, 394 .addr_ihl = 0x22, 395 .mask_ihl = 0x80, 396 .addr_od = 0x22, 397 .mask_od = 0x40, 398 .addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR, 399 }, 400 .multi_read_bit = true, 401 .bootime = 2, 402 }, 403 { 404 /* 405 * CUSTOM VALUES FOR LPS22HB SENSOR 406 * See LPS22HB datasheet: 407 * http://www2.st.com/resource/en/datasheet/lps22hb.pdf 408 */ 409 .wai = 0xb1, 410 .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, 411 .sensors_supported = { 412 [0] = LPS22HB_PRESS_DEV_NAME, 413 }, 414 .ch = (struct iio_chan_spec *)st_press_lps22hb_channels, 415 .num_ch = ARRAY_SIZE(st_press_lps22hb_channels), 416 .odr = { 417 .addr = 0x10, 418 .mask = 0x70, 419 .odr_avl = { 420 { .hz = 1, .value = 0x01 }, 421 { .hz = 10, .value = 0x02 }, 422 { .hz = 25, .value = 0x03 }, 423 { .hz = 50, .value = 0x04 }, 424 { .hz = 75, .value = 0x05 }, 425 }, 426 }, 427 .pw = { 428 .addr = 0x10, 429 .mask = 0x70, 430 .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, 431 }, 432 .fs = { 433 .fs_avl = { 434 /* 435 * Pressure and temperature sensitivity values 436 * as defined in table 3 of LPS22HB datasheet. 437 */ 438 [0] = { 439 .num = ST_PRESS_FS_AVL_1260MB, 440 .gain = ST_PRESS_KPASCAL_NANO_SCALE, 441 .gain2 = ST_PRESS_LPS22HB_LSB_PER_CELSIUS, 442 }, 443 }, 444 }, 445 .bdu = { 446 .addr = 0x10, 447 .mask = 0x02, 448 }, 449 .drdy_irq = { 450 .addr = 0x12, 451 .mask_int1 = 0x04, 452 .mask_int2 = 0x08, 453 .addr_ihl = 0x12, 454 .mask_ihl = 0x80, 455 .addr_od = 0x12, 456 .mask_od = 0x40, 457 .addr_stat_drdy = ST_SENSORS_DEFAULT_STAT_ADDR, 458 }, 459 .multi_read_bit = true, 460 .bootime = 2, 461 }, 462 }; 463 464 static int st_press_write_raw(struct iio_dev *indio_dev, 465 struct iio_chan_spec const *ch, 466 int val, 467 int val2, 468 long mask) 469 { 470 int err; 471 472 switch (mask) { 473 case IIO_CHAN_INFO_SAMP_FREQ: 474 if (val2) 475 return -EINVAL; 476 mutex_lock(&indio_dev->mlock); 477 err = st_sensors_set_odr(indio_dev, val); 478 mutex_unlock(&indio_dev->mlock); 479 return err; 480 default: 481 return -EINVAL; 482 } 483 } 484 485 static int st_press_read_raw(struct iio_dev *indio_dev, 486 struct iio_chan_spec const *ch, int *val, 487 int *val2, long mask) 488 { 489 int err; 490 struct st_sensor_data *press_data = iio_priv(indio_dev); 491 492 switch (mask) { 493 case IIO_CHAN_INFO_RAW: 494 err = st_sensors_read_info_raw(indio_dev, ch, val); 495 if (err < 0) 496 goto read_error; 497 498 return IIO_VAL_INT; 499 case IIO_CHAN_INFO_SCALE: 500 switch (ch->type) { 501 case IIO_PRESSURE: 502 *val = 0; 503 *val2 = press_data->current_fullscale->gain; 504 return IIO_VAL_INT_PLUS_NANO; 505 case IIO_TEMP: 506 *val = MCELSIUS_PER_CELSIUS; 507 *val2 = press_data->current_fullscale->gain2; 508 return IIO_VAL_FRACTIONAL; 509 default: 510 err = -EINVAL; 511 goto read_error; 512 } 513 514 case IIO_CHAN_INFO_OFFSET: 515 switch (ch->type) { 516 case IIO_TEMP: 517 *val = ST_PRESS_MILLI_CELSIUS_OFFSET * 518 press_data->current_fullscale->gain2; 519 *val2 = MCELSIUS_PER_CELSIUS; 520 break; 521 default: 522 err = -EINVAL; 523 goto read_error; 524 } 525 526 return IIO_VAL_FRACTIONAL; 527 case IIO_CHAN_INFO_SAMP_FREQ: 528 *val = press_data->odr; 529 return IIO_VAL_INT; 530 default: 531 return -EINVAL; 532 } 533 534 read_error: 535 return err; 536 } 537 538 static ST_SENSORS_DEV_ATTR_SAMP_FREQ_AVAIL(); 539 540 static struct attribute *st_press_attributes[] = { 541 &iio_dev_attr_sampling_frequency_available.dev_attr.attr, 542 NULL, 543 }; 544 545 static const struct attribute_group st_press_attribute_group = { 546 .attrs = st_press_attributes, 547 }; 548 549 static const struct iio_info press_info = { 550 .driver_module = THIS_MODULE, 551 .attrs = &st_press_attribute_group, 552 .read_raw = &st_press_read_raw, 553 .write_raw = &st_press_write_raw, 554 .debugfs_reg_access = &st_sensors_debugfs_reg_access, 555 }; 556 557 #ifdef CONFIG_IIO_TRIGGER 558 static const struct iio_trigger_ops st_press_trigger_ops = { 559 .owner = THIS_MODULE, 560 .set_trigger_state = ST_PRESS_TRIGGER_SET_STATE, 561 .validate_device = st_sensors_validate_device, 562 }; 563 #define ST_PRESS_TRIGGER_OPS (&st_press_trigger_ops) 564 #else 565 #define ST_PRESS_TRIGGER_OPS NULL 566 #endif 567 568 int st_press_common_probe(struct iio_dev *indio_dev) 569 { 570 struct st_sensor_data *press_data = iio_priv(indio_dev); 571 int irq = press_data->get_irq_data_ready(indio_dev); 572 int err; 573 574 indio_dev->modes = INDIO_DIRECT_MODE; 575 indio_dev->info = &press_info; 576 mutex_init(&press_data->tb.buf_lock); 577 578 err = st_sensors_power_enable(indio_dev); 579 if (err) 580 return err; 581 582 err = st_sensors_check_device_support(indio_dev, 583 ARRAY_SIZE(st_press_sensors_settings), 584 st_press_sensors_settings); 585 if (err < 0) 586 goto st_press_power_off; 587 588 /* 589 * Skip timestamping channel while declaring available channels to 590 * common st_sensor layer. Look at st_sensors_get_buffer_element() to 591 * see how timestamps are explicitly pushed as last samples block 592 * element. 593 */ 594 press_data->num_data_channels = press_data->sensor_settings->num_ch - 1; 595 press_data->multiread_bit = press_data->sensor_settings->multi_read_bit; 596 indio_dev->channels = press_data->sensor_settings->ch; 597 indio_dev->num_channels = press_data->sensor_settings->num_ch; 598 599 press_data->current_fullscale = 600 (struct st_sensor_fullscale_avl *) 601 &press_data->sensor_settings->fs.fs_avl[0]; 602 603 press_data->odr = press_data->sensor_settings->odr.odr_avl[0].hz; 604 605 /* Some devices don't support a data ready pin. */ 606 if (!press_data->dev->platform_data && 607 press_data->sensor_settings->drdy_irq.addr) 608 press_data->dev->platform_data = 609 (struct st_sensors_platform_data *)&default_press_pdata; 610 611 err = st_sensors_init_sensor(indio_dev, press_data->dev->platform_data); 612 if (err < 0) 613 goto st_press_power_off; 614 615 err = st_press_allocate_ring(indio_dev); 616 if (err < 0) 617 goto st_press_power_off; 618 619 if (irq > 0) { 620 err = st_sensors_allocate_trigger(indio_dev, 621 ST_PRESS_TRIGGER_OPS); 622 if (err < 0) 623 goto st_press_probe_trigger_error; 624 } 625 626 err = iio_device_register(indio_dev); 627 if (err) 628 goto st_press_device_register_error; 629 630 dev_info(&indio_dev->dev, "registered pressure sensor %s\n", 631 indio_dev->name); 632 633 return err; 634 635 st_press_device_register_error: 636 if (irq > 0) 637 st_sensors_deallocate_trigger(indio_dev); 638 st_press_probe_trigger_error: 639 st_press_deallocate_ring(indio_dev); 640 st_press_power_off: 641 st_sensors_power_disable(indio_dev); 642 643 return err; 644 } 645 EXPORT_SYMBOL(st_press_common_probe); 646 647 void st_press_common_remove(struct iio_dev *indio_dev) 648 { 649 struct st_sensor_data *press_data = iio_priv(indio_dev); 650 651 st_sensors_power_disable(indio_dev); 652 653 iio_device_unregister(indio_dev); 654 if (press_data->get_irq_data_ready(indio_dev) > 0) 655 st_sensors_deallocate_trigger(indio_dev); 656 657 st_press_deallocate_ring(indio_dev); 658 } 659 EXPORT_SYMBOL(st_press_common_remove); 660 661 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>"); 662 MODULE_DESCRIPTION("STMicroelectronics pressures driver"); 663 MODULE_LICENSE("GPL v2"); 664