1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Measurements Specialties driver common i2c functions 4 * 5 * Copyright (c) 2015 Measurement-Specialties 6 */ 7 8#include <linux/module.h> 9#include <linux/iio/iio.h> 10#include <linux/device.h> 11#include <linux/delay.h> 12 13#include "ms_sensors_i2c.h" 14 15/* Conversion times in us */ 16static const u16 ms_sensors_ht_t_conversion_time[] = { 50000, 25000, 17 13000, 7000 }; 18static const u16 ms_sensors_ht_h_conversion_time[] = { 16000, 5000, 19 3000, 8000 }; 20static const u16 ms_sensors_tp_conversion_time[] = { 500, 1100, 2100, 21 4100, 8220, 16440 }; 22 23#define MS_SENSORS_SERIAL_READ_MSB 0xFA0F 24#define MS_SENSORS_SERIAL_READ_LSB 0xFCC9 25#define MS_SENSORS_CONFIG_REG_WRITE 0xE6 26#define MS_SENSORS_CONFIG_REG_READ 0xE7 27#define MS_SENSORS_HT_T_CONVERSION_START 0xF3 28#define MS_SENSORS_HT_H_CONVERSION_START 0xF5 29 30#define MS_SENSORS_TP_PROM_READ 0xA0 31#define MS_SENSORS_TP_T_CONVERSION_START 0x50 32#define MS_SENSORS_TP_P_CONVERSION_START 0x40 33#define MS_SENSORS_TP_ADC_READ 0x00 34 35#define MS_SENSORS_NO_READ_CMD 0xFF 36 37/** 38 * ms_sensors_reset() - Reset function 39 * @cli: pointer to device client 40 * @cmd: reset cmd. Depends on device in use 41 * @delay: usleep minimal delay after reset command is issued 42 * 43 * Generic I2C reset function for Measurement Specialties devices. 44 * 45 * Return: 0 on success, negative errno otherwise. 46 */ 47int ms_sensors_reset(void *cli, u8 cmd, unsigned int delay) 48{ 49 int ret; 50 struct i2c_client *client = cli; 51 52 ret = i2c_smbus_write_byte(client, cmd); 53 if (ret) { 54 dev_err(&client->dev, "Failed to reset device\n"); 55 return ret; 56 } 57 usleep_range(delay, delay + 1000); 58 59 return 0; 60} 61EXPORT_SYMBOL_NS(ms_sensors_reset, IIO_MEAS_SPEC_SENSORS); 62 63/** 64 * ms_sensors_read_prom_word() - PROM word read function 65 * @cli: pointer to device client 66 * @cmd: PROM read cmd. Depends on device and prom id 67 * @word: pointer to word destination value 68 * 69 * Generic i2c prom word read function for Measurement Specialties devices. 70 * 71 * Return: 0 on success, negative errno otherwise. 72 */ 73int ms_sensors_read_prom_word(void *cli, int cmd, u16 *word) 74{ 75 int ret; 76 struct i2c_client *client = cli; 77 78 ret = i2c_smbus_read_word_swapped(client, cmd); 79 if (ret < 0) { 80 dev_err(&client->dev, "Failed to read prom word\n"); 81 return ret; 82 } 83 *word = ret; 84 85 return 0; 86} 87EXPORT_SYMBOL_NS(ms_sensors_read_prom_word, IIO_MEAS_SPEC_SENSORS); 88 89/** 90 * ms_sensors_convert_and_read() - ADC conversion & read function 91 * @cli: pointer to device client 92 * @conv: ADC conversion command. Depends on device in use 93 * @rd: ADC read command. Depends on device in use 94 * @delay: usleep minimal delay after conversion command is issued 95 * @adc: pointer to ADC destination value 96 * 97 * Generic ADC conversion & read function for Measurement Specialties 98 * devices. 99 * The function will issue conversion command, sleep appopriate delay, and 100 * issue command to read ADC. 101 * 102 * Return: 0 on success, negative errno otherwise. 103 */ 104int ms_sensors_convert_and_read(void *cli, u8 conv, u8 rd, 105 unsigned int delay, u32 *adc) 106{ 107 int ret; 108 __be32 buf = 0; 109 struct i2c_client *client = cli; 110 111 /* Trigger conversion */ 112 ret = i2c_smbus_write_byte(client, conv); 113 if (ret) 114 goto err; 115 usleep_range(delay, delay + 1000); 116 117 /* Retrieve ADC value */ 118 if (rd != MS_SENSORS_NO_READ_CMD) 119 ret = i2c_smbus_read_i2c_block_data(client, rd, 3, (u8 *)&buf); 120 else 121 ret = i2c_master_recv(client, (u8 *)&buf, 3); 122 if (ret < 0) 123 goto err; 124 125 dev_dbg(&client->dev, "ADC raw value : %x\n", be32_to_cpu(buf) >> 8); 126 *adc = be32_to_cpu(buf) >> 8; 127 128 return 0; 129err: 130 dev_err(&client->dev, "Unable to make sensor adc conversion\n"); 131 return ret; 132} 133EXPORT_SYMBOL_NS(ms_sensors_convert_and_read, IIO_MEAS_SPEC_SENSORS); 134 135/** 136 * ms_sensors_crc_valid() - CRC check function 137 * @value: input and CRC compare value 138 * 139 * Cyclic Redundancy Check function used in TSYS02D, HTU21, MS8607. 140 * This function performs a x^8 + x^5 + x^4 + 1 polynomial CRC. 141 * The argument contains CRC value in LSB byte while the bytes 1 and 2 142 * are used for CRC computation. 143 * 144 * Return: 1 if CRC is valid, 0 otherwise. 145 */ 146static bool ms_sensors_crc_valid(u32 value) 147{ 148 u32 polynom = 0x988000; /* x^8 + x^5 + x^4 + 1 */ 149 u32 msb = 0x800000; 150 u32 mask = 0xFF8000; 151 u32 result = value & 0xFFFF00; 152 u8 crc = value & 0xFF; 153 154 while (msb != 0x80) { 155 if (result & msb) 156 result = ((result ^ polynom) & mask) 157 | (result & ~mask); 158 msb >>= 1; 159 mask >>= 1; 160 polynom >>= 1; 161 } 162 163 return result == crc; 164} 165 166/** 167 * ms_sensors_read_serial() - Serial number read function 168 * @client: pointer to i2c client 169 * @sn: pointer to 64-bits destination value 170 * 171 * Generic i2c serial number read function for Measurement Specialties devices. 172 * This function is used for TSYS02d, HTU21, MS8607 chipset. 173 * Refer to datasheet: 174 * http://www.meas-spec.com/downloads/HTU2X_Serial_Number_Reading.pdf 175 * 176 * Sensor raw MSB serial number format is the following : 177 * [ SNB3, CRC, SNB2, CRC, SNB1, CRC, SNB0, CRC] 178 * Sensor raw LSB serial number format is the following : 179 * [ X, X, SNC1, SNC0, CRC, SNA1, SNA0, CRC] 180 * The resulting serial number is following : 181 * [ SNA1, SNA0, SNB3, SNB2, SNB1, SNB0, SNC1, SNC0] 182 * 183 * Return: 0 on success, negative errno otherwise. 184 */ 185int ms_sensors_read_serial(struct i2c_client *client, u64 *sn) 186{ 187 u8 i; 188 __be64 rcv_buf = 0; 189 u64 rcv_val; 190 __be16 send_buf; 191 int ret; 192 193 struct i2c_msg msg[2] = { 194 { 195 .addr = client->addr, 196 .flags = client->flags, 197 .len = 2, 198 .buf = (__u8 *)&send_buf, 199 }, 200 { 201 .addr = client->addr, 202 .flags = client->flags | I2C_M_RD, 203 .buf = (__u8 *)&rcv_buf, 204 }, 205 }; 206 207 /* Read MSB part of serial number */ 208 send_buf = cpu_to_be16(MS_SENSORS_SERIAL_READ_MSB); 209 msg[1].len = 8; 210 ret = i2c_transfer(client->adapter, msg, 2); 211 if (ret < 0) { 212 dev_err(&client->dev, "Unable to read device serial number"); 213 return ret; 214 } 215 216 rcv_val = be64_to_cpu(rcv_buf); 217 dev_dbg(&client->dev, "Serial MSB raw : %llx\n", rcv_val); 218 219 for (i = 0; i < 64; i += 16) { 220 if (!ms_sensors_crc_valid((rcv_val >> i) & 0xFFFF)) 221 return -ENODEV; 222 } 223 224 *sn = (((rcv_val >> 32) & 0xFF000000) | 225 ((rcv_val >> 24) & 0x00FF0000) | 226 ((rcv_val >> 16) & 0x0000FF00) | 227 ((rcv_val >> 8) & 0x000000FF)) << 16; 228 229 /* Read LSB part of serial number */ 230 send_buf = cpu_to_be16(MS_SENSORS_SERIAL_READ_LSB); 231 msg[1].len = 6; 232 rcv_buf = 0; 233 ret = i2c_transfer(client->adapter, msg, 2); 234 if (ret < 0) { 235 dev_err(&client->dev, "Unable to read device serial number"); 236 return ret; 237 } 238 239 rcv_val = be64_to_cpu(rcv_buf) >> 16; 240 dev_dbg(&client->dev, "Serial MSB raw : %llx\n", rcv_val); 241 242 for (i = 0; i < 48; i += 24) { 243 if (!ms_sensors_crc_valid((rcv_val >> i) & 0xFFFFFF)) 244 return -ENODEV; 245 } 246 247 *sn |= (rcv_val & 0xFFFF00) << 40 | (rcv_val >> 32); 248 249 return 0; 250} 251EXPORT_SYMBOL_NS(ms_sensors_read_serial, IIO_MEAS_SPEC_SENSORS); 252 253static int ms_sensors_read_config_reg(struct i2c_client *client, 254 u8 *config_reg) 255{ 256 int ret; 257 258 ret = i2c_smbus_write_byte(client, MS_SENSORS_CONFIG_REG_READ); 259 if (ret) { 260 dev_err(&client->dev, "Unable to read config register"); 261 return ret; 262 } 263 264 ret = i2c_master_recv(client, config_reg, 1); 265 if (ret < 0) { 266 dev_err(&client->dev, "Unable to read config register"); 267 return ret; 268 } 269 dev_dbg(&client->dev, "Config register :%x\n", *config_reg); 270 271 return 0; 272} 273 274/** 275 * ms_sensors_write_resolution() - Set resolution function 276 * @dev_data: pointer to temperature/humidity device data 277 * @i: resolution index to set 278 * 279 * This function will program the appropriate resolution based on the index 280 * provided when user space will set samp_freq channel. 281 * This function is used for TSYS02D, HTU21 and MS8607 chipsets. 282 * 283 * Return: 0 on success, negative errno otherwise. 284 */ 285ssize_t ms_sensors_write_resolution(struct ms_ht_dev *dev_data, 286 u8 i) 287{ 288 u8 config_reg; 289 int ret; 290 291 ret = ms_sensors_read_config_reg(dev_data->client, &config_reg); 292 if (ret) 293 return ret; 294 295 config_reg &= 0x7E; 296 config_reg |= ((i & 1) << 7) + ((i & 2) >> 1); 297 298 return i2c_smbus_write_byte_data(dev_data->client, 299 MS_SENSORS_CONFIG_REG_WRITE, 300 config_reg); 301} 302EXPORT_SYMBOL_NS(ms_sensors_write_resolution, IIO_MEAS_SPEC_SENSORS); 303 304/** 305 * ms_sensors_show_battery_low() - Show device battery low indicator 306 * @dev_data: pointer to temperature/humidity device data 307 * @buf: pointer to char buffer to write result 308 * 309 * This function will read battery indicator value in the device and 310 * return 1 if the device voltage is below 2.25V. 311 * This function is used for TSYS02D, HTU21 and MS8607 chipsets. 312 * 313 * Return: length of sprintf on success, negative errno otherwise. 314 */ 315ssize_t ms_sensors_show_battery_low(struct ms_ht_dev *dev_data, 316 char *buf) 317{ 318 int ret; 319 u8 config_reg; 320 321 mutex_lock(&dev_data->lock); 322 ret = ms_sensors_read_config_reg(dev_data->client, &config_reg); 323 mutex_unlock(&dev_data->lock); 324 if (ret) 325 return ret; 326 327 return sysfs_emit(buf, "%d\n", (config_reg & 0x40) >> 6); 328} 329EXPORT_SYMBOL_NS(ms_sensors_show_battery_low, IIO_MEAS_SPEC_SENSORS); 330 331/** 332 * ms_sensors_show_heater() - Show device heater 333 * @dev_data: pointer to temperature/humidity device data 334 * @buf: pointer to char buffer to write result 335 * 336 * This function will read heater enable value in the device and 337 * return 1 if the heater is enabled. 338 * This function is used for HTU21 and MS8607 chipsets. 339 * 340 * Return: length of sprintf on success, negative errno otherwise. 341 */ 342ssize_t ms_sensors_show_heater(struct ms_ht_dev *dev_data, 343 char *buf) 344{ 345 u8 config_reg; 346 int ret; 347 348 mutex_lock(&dev_data->lock); 349 ret = ms_sensors_read_config_reg(dev_data->client, &config_reg); 350 mutex_unlock(&dev_data->lock); 351 if (ret) 352 return ret; 353 354 return sysfs_emit(buf, "%d\n", (config_reg & 0x4) >> 2); 355} 356EXPORT_SYMBOL_NS(ms_sensors_show_heater, IIO_MEAS_SPEC_SENSORS); 357 358/** 359 * ms_sensors_write_heater() - Write device heater 360 * @dev_data: pointer to temperature/humidity device data 361 * @buf: pointer to char buffer from user space 362 * @len: length of buf 363 * 364 * This function will write 1 or 0 value in the device 365 * to enable or disable heater. 366 * This function is used for HTU21 and MS8607 chipsets. 367 * 368 * Return: length of buffer, negative errno otherwise. 369 */ 370ssize_t ms_sensors_write_heater(struct ms_ht_dev *dev_data, 371 const char *buf, size_t len) 372{ 373 u8 val, config_reg; 374 int ret; 375 376 ret = kstrtou8(buf, 10, &val); 377 if (ret) 378 return ret; 379 380 if (val > 1) 381 return -EINVAL; 382 383 mutex_lock(&dev_data->lock); 384 ret = ms_sensors_read_config_reg(dev_data->client, &config_reg); 385 if (ret) { 386 mutex_unlock(&dev_data->lock); 387 return ret; 388 } 389 390 config_reg &= 0xFB; 391 config_reg |= val << 2; 392 393 ret = i2c_smbus_write_byte_data(dev_data->client, 394 MS_SENSORS_CONFIG_REG_WRITE, 395 config_reg); 396 mutex_unlock(&dev_data->lock); 397 if (ret) { 398 dev_err(&dev_data->client->dev, "Unable to write config register\n"); 399 return ret; 400 } 401 402 return len; 403} 404EXPORT_SYMBOL_NS(ms_sensors_write_heater, IIO_MEAS_SPEC_SENSORS); 405 406/** 407 * ms_sensors_ht_read_temperature() - Read temperature 408 * @dev_data: pointer to temperature/humidity device data 409 * @temperature:pointer to temperature destination value 410 * 411 * This function will get temperature ADC value from the device, 412 * check the CRC and compute the temperature value. 413 * This function is used for TSYS02D, HTU21 and MS8607 chipsets. 414 * 415 * Return: 0 on success, negative errno otherwise. 416 */ 417int ms_sensors_ht_read_temperature(struct ms_ht_dev *dev_data, 418 s32 *temperature) 419{ 420 int ret; 421 u32 adc; 422 u16 delay; 423 424 mutex_lock(&dev_data->lock); 425 delay = ms_sensors_ht_t_conversion_time[dev_data->res_index]; 426 ret = ms_sensors_convert_and_read(dev_data->client, 427 MS_SENSORS_HT_T_CONVERSION_START, 428 MS_SENSORS_NO_READ_CMD, 429 delay, &adc); 430 mutex_unlock(&dev_data->lock); 431 if (ret) 432 return ret; 433 434 if (!ms_sensors_crc_valid(adc)) { 435 dev_err(&dev_data->client->dev, 436 "Temperature read crc check error\n"); 437 return -ENODEV; 438 } 439 440 /* Temperature algorithm */ 441 *temperature = (((s64)(adc >> 8) * 175720) >> 16) - 46850; 442 443 return 0; 444} 445EXPORT_SYMBOL_NS(ms_sensors_ht_read_temperature, IIO_MEAS_SPEC_SENSORS); 446 447/** 448 * ms_sensors_ht_read_humidity() - Read humidity 449 * @dev_data: pointer to temperature/humidity device data 450 * @humidity: pointer to humidity destination value 451 * 452 * This function will get humidity ADC value from the device, 453 * check the CRC and compute the temperature value. 454 * This function is used for HTU21 and MS8607 chipsets. 455 * 456 * Return: 0 on success, negative errno otherwise. 457 */ 458int ms_sensors_ht_read_humidity(struct ms_ht_dev *dev_data, 459 u32 *humidity) 460{ 461 int ret; 462 u32 adc; 463 u16 delay; 464 465 mutex_lock(&dev_data->lock); 466 delay = ms_sensors_ht_h_conversion_time[dev_data->res_index]; 467 ret = ms_sensors_convert_and_read(dev_data->client, 468 MS_SENSORS_HT_H_CONVERSION_START, 469 MS_SENSORS_NO_READ_CMD, 470 delay, &adc); 471 mutex_unlock(&dev_data->lock); 472 if (ret) 473 return ret; 474 475 if (!ms_sensors_crc_valid(adc)) { 476 dev_err(&dev_data->client->dev, 477 "Humidity read crc check error\n"); 478 return -ENODEV; 479 } 480 481 /* Humidity algorithm */ 482 *humidity = (((s32)(adc >> 8) * 12500) >> 16) * 10 - 6000; 483 if (*humidity >= 100000) 484 *humidity = 100000; 485 486 return 0; 487} 488EXPORT_SYMBOL_NS(ms_sensors_ht_read_humidity, IIO_MEAS_SPEC_SENSORS); 489 490/** 491 * ms_sensors_tp_crc4() - Calculate PROM CRC for 492 * Temperature and pressure devices. 493 * This function is only used when reading PROM coefficients 494 * 495 * @prom: pointer to PROM coefficients array 496 * 497 * Return: CRC. 498 */ 499static u8 ms_sensors_tp_crc4(u16 *prom) 500{ 501 unsigned int cnt, n_bit; 502 u16 n_rem = 0x0000; 503 504 for (cnt = 0; cnt < MS_SENSORS_TP_PROM_WORDS_NB * 2; cnt++) { 505 if (cnt % 2 == 1) 506 n_rem ^= prom[cnt >> 1] & 0x00FF; 507 else 508 n_rem ^= prom[cnt >> 1] >> 8; 509 510 for (n_bit = 8; n_bit > 0; n_bit--) { 511 if (n_rem & 0x8000) 512 n_rem = (n_rem << 1) ^ 0x3000; 513 else 514 n_rem <<= 1; 515 } 516 } 517 518 return n_rem >> 12; 519} 520 521/** 522 * ms_sensors_tp_crc_valid_112() - CRC check function for 523 * Temperature and pressure devices for 112bit PROM. 524 * This function is only used when reading PROM coefficients 525 * 526 * @prom: pointer to PROM coefficients array 527 * 528 * Return: True if CRC is ok. 529 */ 530static bool ms_sensors_tp_crc_valid_112(u16 *prom) 531{ 532 u16 w0 = prom[0], crc_read = (w0 & 0xF000) >> 12; 533 u8 crc; 534 535 prom[0] &= 0x0FFF; /* Clear the CRC computation part */ 536 prom[MS_SENSORS_TP_PROM_WORDS_NB - 1] = 0; 537 538 crc = ms_sensors_tp_crc4(prom); 539 540 prom[0] = w0; 541 542 return crc == crc_read; 543} 544 545/** 546 * ms_sensors_tp_crc_valid_128() - CRC check function for 547 * Temperature and pressure devices for 128bit PROM. 548 * This function is only used when reading PROM coefficients 549 * 550 * @prom: pointer to PROM coefficients array 551 * 552 * Return: True if CRC is ok. 553 */ 554static bool ms_sensors_tp_crc_valid_128(u16 *prom) 555{ 556 u16 w7 = prom[7], crc_read = w7 & 0x000F; 557 u8 crc; 558 559 prom[7] &= 0xFF00; /* Clear the CRC and LSB part */ 560 561 crc = ms_sensors_tp_crc4(prom); 562 563 prom[7] = w7; 564 565 return crc == crc_read; 566} 567 568/** 569 * ms_sensors_tp_read_prom() - prom coeff read function 570 * @dev_data: pointer to temperature/pressure device data 571 * 572 * This function will read prom coefficients and check CRC. 573 * This function is used for MS5637 and MS8607 chipsets. 574 * 575 * Return: 0 on success, negative errno otherwise. 576 */ 577int ms_sensors_tp_read_prom(struct ms_tp_dev *dev_data) 578{ 579 int i, ret; 580 bool valid; 581 582 for (i = 0; i < dev_data->hw->prom_len; i++) { 583 ret = ms_sensors_read_prom_word( 584 dev_data->client, 585 MS_SENSORS_TP_PROM_READ + (i << 1), 586 &dev_data->prom[i]); 587 588 if (ret) 589 return ret; 590 } 591 592 if (dev_data->hw->prom_len == 8) 593 valid = ms_sensors_tp_crc_valid_128(dev_data->prom); 594 else 595 valid = ms_sensors_tp_crc_valid_112(dev_data->prom); 596 597 if (!valid) { 598 dev_err(&dev_data->client->dev, 599 "Calibration coefficients crc check error\n"); 600 return -ENODEV; 601 } 602 603 return 0; 604} 605EXPORT_SYMBOL_NS(ms_sensors_tp_read_prom, IIO_MEAS_SPEC_SENSORS); 606 607/** 608 * ms_sensors_read_temp_and_pressure() - read temp and pressure 609 * @dev_data: pointer to temperature/pressure device data 610 * @temperature:pointer to temperature destination value 611 * @pressure: pointer to pressure destination value 612 * 613 * This function will read ADC and compute pressure and temperature value. 614 * This function is used for MS5637 and MS8607 chipsets. 615 * 616 * Return: 0 on success, negative errno otherwise. 617 */ 618int ms_sensors_read_temp_and_pressure(struct ms_tp_dev *dev_data, 619 int *temperature, 620 unsigned int *pressure) 621{ 622 int ret; 623 u32 t_adc, p_adc; 624 s32 dt, temp; 625 s64 off, sens, t2, off2, sens2; 626 u16 *prom = dev_data->prom, delay; 627 628 mutex_lock(&dev_data->lock); 629 delay = ms_sensors_tp_conversion_time[dev_data->res_index]; 630 631 ret = ms_sensors_convert_and_read( 632 dev_data->client, 633 MS_SENSORS_TP_T_CONVERSION_START + 634 dev_data->res_index * 2, 635 MS_SENSORS_TP_ADC_READ, 636 delay, &t_adc); 637 if (ret) { 638 mutex_unlock(&dev_data->lock); 639 return ret; 640 } 641 642 ret = ms_sensors_convert_and_read( 643 dev_data->client, 644 MS_SENSORS_TP_P_CONVERSION_START + 645 dev_data->res_index * 2, 646 MS_SENSORS_TP_ADC_READ, 647 delay, &p_adc); 648 mutex_unlock(&dev_data->lock); 649 if (ret) 650 return ret; 651 652 dt = (s32)t_adc - (prom[5] << 8); 653 654 /* Actual temperature = 2000 + dT * TEMPSENS */ 655 temp = 2000 + (((s64)dt * prom[6]) >> 23); 656 657 /* Second order temperature compensation */ 658 if (temp < 2000) { 659 s64 tmp = (s64)temp - 2000; 660 661 t2 = (3 * ((s64)dt * (s64)dt)) >> 33; 662 off2 = (61 * tmp * tmp) >> 4; 663 sens2 = (29 * tmp * tmp) >> 4; 664 665 if (temp < -1500) { 666 s64 tmp = (s64)temp + 1500; 667 668 off2 += 17 * tmp * tmp; 669 sens2 += 9 * tmp * tmp; 670 } 671 } else { 672 t2 = (5 * ((s64)dt * (s64)dt)) >> 38; 673 off2 = 0; 674 sens2 = 0; 675 } 676 677 /* OFF = OFF_T1 + TCO * dT */ 678 off = (((s64)prom[2]) << 17) + ((((s64)prom[4]) * (s64)dt) >> 6); 679 off -= off2; 680 681 /* Sensitivity at actual temperature = SENS_T1 + TCS * dT */ 682 sens = (((s64)prom[1]) << 16) + (((s64)prom[3] * dt) >> 7); 683 sens -= sens2; 684 685 /* Temperature compensated pressure = D1 * SENS - OFF */ 686 *temperature = (temp - t2) * 10; 687 *pressure = (u32)(((((s64)p_adc * sens) >> 21) - off) >> 15); 688 689 return 0; 690} 691EXPORT_SYMBOL_NS(ms_sensors_read_temp_and_pressure, IIO_MEAS_SPEC_SENSORS); 692 693MODULE_DESCRIPTION("Measurement-Specialties common i2c driver"); 694MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>"); 695MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>"); 696MODULE_LICENSE("GPL v2"); 697 698