1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com> 4 * Copyright (c) 2012 Bosch Sensortec GmbH 5 * Copyright (c) 2012 Unixphere AB 6 * Copyright (c) 2014 Intel Corporation 7 * Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org> 8 * 9 * Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor. 10 * 11 * Datasheet: 12 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf 13 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf 14 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf 15 */ 16 17 #define pr_fmt(fmt) "bmp280: " fmt 18 19 #include <linux/device.h> 20 #include <linux/module.h> 21 #include <linux/regmap.h> 22 #include <linux/delay.h> 23 #include <linux/iio/iio.h> 24 #include <linux/iio/sysfs.h> 25 #include <linux/gpio/consumer.h> 26 #include <linux/regulator/consumer.h> 27 #include <linux/interrupt.h> 28 #include <linux/irq.h> /* For irq_get_irq_data() */ 29 #include <linux/completion.h> 30 #include <linux/pm_runtime.h> 31 #include <linux/random.h> 32 33 #include "bmp280.h" 34 35 /* 36 * These enums are used for indexing into the array of calibration 37 * coefficients for BMP180. 38 */ 39 enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD }; 40 41 struct bmp180_calib { 42 s16 AC1; 43 s16 AC2; 44 s16 AC3; 45 u16 AC4; 46 u16 AC5; 47 u16 AC6; 48 s16 B1; 49 s16 B2; 50 s16 MB; 51 s16 MC; 52 s16 MD; 53 }; 54 55 /* See datasheet Section 4.2.2. */ 56 struct bmp280_calib { 57 u16 T1; 58 s16 T2; 59 s16 T3; 60 u16 P1; 61 s16 P2; 62 s16 P3; 63 s16 P4; 64 s16 P5; 65 s16 P6; 66 s16 P7; 67 s16 P8; 68 s16 P9; 69 u8 H1; 70 s16 H2; 71 u8 H3; 72 s16 H4; 73 s16 H5; 74 s8 H6; 75 }; 76 77 static const char *const bmp280_supply_names[] = { 78 "vddd", "vdda" 79 }; 80 81 #define BMP280_NUM_SUPPLIES ARRAY_SIZE(bmp280_supply_names) 82 83 struct bmp280_data { 84 struct device *dev; 85 struct mutex lock; 86 struct regmap *regmap; 87 struct completion done; 88 bool use_eoc; 89 const struct bmp280_chip_info *chip_info; 90 union { 91 struct bmp180_calib bmp180; 92 struct bmp280_calib bmp280; 93 } calib; 94 struct regulator_bulk_data supplies[BMP280_NUM_SUPPLIES]; 95 unsigned int start_up_time; /* in microseconds */ 96 97 /* log of base 2 of oversampling rate */ 98 u8 oversampling_press; 99 u8 oversampling_temp; 100 u8 oversampling_humid; 101 102 /* 103 * Carryover value from temperature conversion, used in pressure 104 * calculation. 105 */ 106 s32 t_fine; 107 }; 108 109 struct bmp280_chip_info { 110 const int *oversampling_temp_avail; 111 int num_oversampling_temp_avail; 112 113 const int *oversampling_press_avail; 114 int num_oversampling_press_avail; 115 116 const int *oversampling_humid_avail; 117 int num_oversampling_humid_avail; 118 119 int (*chip_config)(struct bmp280_data *); 120 int (*read_temp)(struct bmp280_data *, int *); 121 int (*read_press)(struct bmp280_data *, int *, int *); 122 int (*read_humid)(struct bmp280_data *, int *, int *); 123 }; 124 125 /* 126 * These enums are used for indexing into the array of compensation 127 * parameters for BMP280. 128 */ 129 enum { T1, T2, T3 }; 130 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 }; 131 132 static const struct iio_chan_spec bmp280_channels[] = { 133 { 134 .type = IIO_PRESSURE, 135 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 136 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 137 }, 138 { 139 .type = IIO_TEMP, 140 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 141 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 142 }, 143 { 144 .type = IIO_HUMIDITYRELATIVE, 145 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 146 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 147 }, 148 }; 149 150 static int bmp280_read_calib(struct bmp280_data *data, 151 struct bmp280_calib *calib, 152 unsigned int chip) 153 { 154 int ret; 155 unsigned int tmp; 156 __le16 l16; 157 __be16 b16; 158 struct device *dev = data->dev; 159 __le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2]; 160 __le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2]; 161 162 /* Read temperature calibration values. */ 163 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START, 164 t_buf, BMP280_COMP_TEMP_REG_COUNT); 165 if (ret < 0) { 166 dev_err(data->dev, 167 "failed to read temperature calibration parameters\n"); 168 return ret; 169 } 170 171 /* Toss the temperature calibration data into the entropy pool */ 172 add_device_randomness(t_buf, sizeof(t_buf)); 173 174 calib->T1 = le16_to_cpu(t_buf[T1]); 175 calib->T2 = le16_to_cpu(t_buf[T2]); 176 calib->T3 = le16_to_cpu(t_buf[T3]); 177 178 /* Read pressure calibration values. */ 179 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START, 180 p_buf, BMP280_COMP_PRESS_REG_COUNT); 181 if (ret < 0) { 182 dev_err(data->dev, 183 "failed to read pressure calibration parameters\n"); 184 return ret; 185 } 186 187 /* Toss the pressure calibration data into the entropy pool */ 188 add_device_randomness(p_buf, sizeof(p_buf)); 189 190 calib->P1 = le16_to_cpu(p_buf[P1]); 191 calib->P2 = le16_to_cpu(p_buf[P2]); 192 calib->P3 = le16_to_cpu(p_buf[P3]); 193 calib->P4 = le16_to_cpu(p_buf[P4]); 194 calib->P5 = le16_to_cpu(p_buf[P5]); 195 calib->P6 = le16_to_cpu(p_buf[P6]); 196 calib->P7 = le16_to_cpu(p_buf[P7]); 197 calib->P8 = le16_to_cpu(p_buf[P8]); 198 calib->P9 = le16_to_cpu(p_buf[P9]); 199 200 /* 201 * Read humidity calibration values. 202 * Due to some odd register addressing we cannot just 203 * do a big bulk read. Instead, we have to read each Hx 204 * value separately and sometimes do some bit shifting... 205 * Humidity data is only available on BME280. 206 */ 207 if (chip != BME280_CHIP_ID) 208 return 0; 209 210 ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp); 211 if (ret < 0) { 212 dev_err(dev, "failed to read H1 comp value\n"); 213 return ret; 214 } 215 calib->H1 = tmp; 216 217 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &l16, 2); 218 if (ret < 0) { 219 dev_err(dev, "failed to read H2 comp value\n"); 220 return ret; 221 } 222 calib->H2 = sign_extend32(le16_to_cpu(l16), 15); 223 224 ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp); 225 if (ret < 0) { 226 dev_err(dev, "failed to read H3 comp value\n"); 227 return ret; 228 } 229 calib->H3 = tmp; 230 231 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &b16, 2); 232 if (ret < 0) { 233 dev_err(dev, "failed to read H4 comp value\n"); 234 return ret; 235 } 236 calib->H4 = sign_extend32(((be16_to_cpu(b16) >> 4) & 0xff0) | 237 (be16_to_cpu(b16) & 0xf), 11); 238 239 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &l16, 2); 240 if (ret < 0) { 241 dev_err(dev, "failed to read H5 comp value\n"); 242 return ret; 243 } 244 calib->H5 = sign_extend32(((le16_to_cpu(l16) >> 4) & 0xfff), 11); 245 246 ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp); 247 if (ret < 0) { 248 dev_err(dev, "failed to read H6 comp value\n"); 249 return ret; 250 } 251 calib->H6 = sign_extend32(tmp, 7); 252 253 return 0; 254 } 255 /* 256 * Returns humidity in percent, resolution is 0.01 percent. Output value of 257 * "47445" represents 47445/1024 = 46.333 %RH. 258 * 259 * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula". 260 */ 261 static u32 bmp280_compensate_humidity(struct bmp280_data *data, 262 s32 adc_humidity) 263 { 264 s32 var; 265 struct bmp280_calib *calib = &data->calib.bmp280; 266 267 var = ((s32)data->t_fine) - (s32)76800; 268 var = ((((adc_humidity << 14) - (calib->H4 << 20) - (calib->H5 * var)) 269 + (s32)16384) >> 15) * (((((((var * calib->H6) >> 10) 270 * (((var * (s32)calib->H3) >> 11) + (s32)32768)) >> 10) 271 + (s32)2097152) * calib->H2 + 8192) >> 14); 272 var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4; 273 274 return var >> 12; 275 }; 276 277 /* 278 * Returns temperature in DegC, resolution is 0.01 DegC. Output value of 279 * "5123" equals 51.23 DegC. t_fine carries fine temperature as global 280 * value. 281 * 282 * Taken from datasheet, Section 3.11.3, "Compensation formula". 283 */ 284 static s32 bmp280_compensate_temp(struct bmp280_data *data, 285 s32 adc_temp) 286 { 287 s32 var1, var2; 288 struct bmp280_calib *calib = &data->calib.bmp280; 289 290 var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) * 291 ((s32)calib->T2)) >> 11; 292 var2 = (((((adc_temp >> 4) - ((s32)calib->T1)) * 293 ((adc_temp >> 4) - ((s32)calib->T1))) >> 12) * 294 ((s32)calib->T3)) >> 14; 295 data->t_fine = var1 + var2; 296 297 return (data->t_fine * 5 + 128) >> 8; 298 } 299 300 /* 301 * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 302 * integer bits and 8 fractional bits). Output value of "24674867" 303 * represents 24674867/256 = 96386.2 Pa = 963.862 hPa 304 * 305 * Taken from datasheet, Section 3.11.3, "Compensation formula". 306 */ 307 static u32 bmp280_compensate_press(struct bmp280_data *data, 308 s32 adc_press) 309 { 310 s64 var1, var2, p; 311 struct bmp280_calib *calib = &data->calib.bmp280; 312 313 var1 = ((s64)data->t_fine) - 128000; 314 var2 = var1 * var1 * (s64)calib->P6; 315 var2 += (var1 * (s64)calib->P5) << 17; 316 var2 += ((s64)calib->P4) << 35; 317 var1 = ((var1 * var1 * (s64)calib->P3) >> 8) + 318 ((var1 * (s64)calib->P2) << 12); 319 var1 = ((((s64)1) << 47) + var1) * ((s64)calib->P1) >> 33; 320 321 if (var1 == 0) 322 return 0; 323 324 p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125; 325 p = div64_s64(p, var1); 326 var1 = (((s64)calib->P9) * (p >> 13) * (p >> 13)) >> 25; 327 var2 = ((s64)(calib->P8) * p) >> 19; 328 p = ((p + var1 + var2) >> 8) + (((s64)calib->P7) << 4); 329 330 return (u32)p; 331 } 332 333 static int bmp280_read_temp(struct bmp280_data *data, 334 int *val) 335 { 336 int ret; 337 __be32 tmp = 0; 338 s32 adc_temp, comp_temp; 339 340 ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, 341 (u8 *) &tmp, 3); 342 if (ret < 0) { 343 dev_err(data->dev, "failed to read temperature\n"); 344 return ret; 345 } 346 347 adc_temp = be32_to_cpu(tmp) >> 12; 348 if (adc_temp == BMP280_TEMP_SKIPPED) { 349 /* reading was skipped */ 350 dev_err(data->dev, "reading temperature skipped\n"); 351 return -EIO; 352 } 353 comp_temp = bmp280_compensate_temp(data, adc_temp); 354 355 /* 356 * val might be NULL if we're called by the read_press routine, 357 * who only cares about the carry over t_fine value. 358 */ 359 if (val) { 360 *val = comp_temp * 10; 361 return IIO_VAL_INT; 362 } 363 364 return 0; 365 } 366 367 static int bmp280_read_press(struct bmp280_data *data, 368 int *val, int *val2) 369 { 370 int ret; 371 __be32 tmp = 0; 372 s32 adc_press; 373 u32 comp_press; 374 375 /* Read and compensate temperature so we get a reading of t_fine. */ 376 ret = bmp280_read_temp(data, NULL); 377 if (ret < 0) 378 return ret; 379 380 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, 381 (u8 *) &tmp, 3); 382 if (ret < 0) { 383 dev_err(data->dev, "failed to read pressure\n"); 384 return ret; 385 } 386 387 adc_press = be32_to_cpu(tmp) >> 12; 388 if (adc_press == BMP280_PRESS_SKIPPED) { 389 /* reading was skipped */ 390 dev_err(data->dev, "reading pressure skipped\n"); 391 return -EIO; 392 } 393 comp_press = bmp280_compensate_press(data, adc_press); 394 395 *val = comp_press; 396 *val2 = 256000; 397 398 return IIO_VAL_FRACTIONAL; 399 } 400 401 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2) 402 { 403 int ret; 404 __be16 tmp = 0; 405 s32 adc_humidity; 406 u32 comp_humidity; 407 408 /* Read and compensate temperature so we get a reading of t_fine. */ 409 ret = bmp280_read_temp(data, NULL); 410 if (ret < 0) 411 return ret; 412 413 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, 414 (u8 *) &tmp, 2); 415 if (ret < 0) { 416 dev_err(data->dev, "failed to read humidity\n"); 417 return ret; 418 } 419 420 adc_humidity = be16_to_cpu(tmp); 421 if (adc_humidity == BMP280_HUMIDITY_SKIPPED) { 422 /* reading was skipped */ 423 dev_err(data->dev, "reading humidity skipped\n"); 424 return -EIO; 425 } 426 comp_humidity = bmp280_compensate_humidity(data, adc_humidity); 427 428 *val = comp_humidity * 1000 / 1024; 429 430 return IIO_VAL_INT; 431 } 432 433 static int bmp280_read_raw(struct iio_dev *indio_dev, 434 struct iio_chan_spec const *chan, 435 int *val, int *val2, long mask) 436 { 437 int ret; 438 struct bmp280_data *data = iio_priv(indio_dev); 439 440 pm_runtime_get_sync(data->dev); 441 mutex_lock(&data->lock); 442 443 switch (mask) { 444 case IIO_CHAN_INFO_PROCESSED: 445 switch (chan->type) { 446 case IIO_HUMIDITYRELATIVE: 447 ret = data->chip_info->read_humid(data, val, val2); 448 break; 449 case IIO_PRESSURE: 450 ret = data->chip_info->read_press(data, val, val2); 451 break; 452 case IIO_TEMP: 453 ret = data->chip_info->read_temp(data, val); 454 break; 455 default: 456 ret = -EINVAL; 457 break; 458 } 459 break; 460 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 461 switch (chan->type) { 462 case IIO_HUMIDITYRELATIVE: 463 *val = 1 << data->oversampling_humid; 464 ret = IIO_VAL_INT; 465 break; 466 case IIO_PRESSURE: 467 *val = 1 << data->oversampling_press; 468 ret = IIO_VAL_INT; 469 break; 470 case IIO_TEMP: 471 *val = 1 << data->oversampling_temp; 472 ret = IIO_VAL_INT; 473 break; 474 default: 475 ret = -EINVAL; 476 break; 477 } 478 break; 479 default: 480 ret = -EINVAL; 481 break; 482 } 483 484 mutex_unlock(&data->lock); 485 pm_runtime_mark_last_busy(data->dev); 486 pm_runtime_put_autosuspend(data->dev); 487 488 return ret; 489 } 490 491 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data, 492 int val) 493 { 494 int i; 495 const int *avail = data->chip_info->oversampling_humid_avail; 496 const int n = data->chip_info->num_oversampling_humid_avail; 497 498 for (i = 0; i < n; i++) { 499 if (avail[i] == val) { 500 data->oversampling_humid = ilog2(val); 501 502 return data->chip_info->chip_config(data); 503 } 504 } 505 return -EINVAL; 506 } 507 508 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data, 509 int val) 510 { 511 int i; 512 const int *avail = data->chip_info->oversampling_temp_avail; 513 const int n = data->chip_info->num_oversampling_temp_avail; 514 515 for (i = 0; i < n; i++) { 516 if (avail[i] == val) { 517 data->oversampling_temp = ilog2(val); 518 519 return data->chip_info->chip_config(data); 520 } 521 } 522 return -EINVAL; 523 } 524 525 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data, 526 int val) 527 { 528 int i; 529 const int *avail = data->chip_info->oversampling_press_avail; 530 const int n = data->chip_info->num_oversampling_press_avail; 531 532 for (i = 0; i < n; i++) { 533 if (avail[i] == val) { 534 data->oversampling_press = ilog2(val); 535 536 return data->chip_info->chip_config(data); 537 } 538 } 539 return -EINVAL; 540 } 541 542 static int bmp280_write_raw(struct iio_dev *indio_dev, 543 struct iio_chan_spec const *chan, 544 int val, int val2, long mask) 545 { 546 int ret = 0; 547 struct bmp280_data *data = iio_priv(indio_dev); 548 549 switch (mask) { 550 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 551 pm_runtime_get_sync(data->dev); 552 mutex_lock(&data->lock); 553 switch (chan->type) { 554 case IIO_HUMIDITYRELATIVE: 555 ret = bmp280_write_oversampling_ratio_humid(data, val); 556 break; 557 case IIO_PRESSURE: 558 ret = bmp280_write_oversampling_ratio_press(data, val); 559 break; 560 case IIO_TEMP: 561 ret = bmp280_write_oversampling_ratio_temp(data, val); 562 break; 563 default: 564 ret = -EINVAL; 565 break; 566 } 567 mutex_unlock(&data->lock); 568 pm_runtime_mark_last_busy(data->dev); 569 pm_runtime_put_autosuspend(data->dev); 570 break; 571 default: 572 return -EINVAL; 573 } 574 575 return ret; 576 } 577 578 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n) 579 { 580 size_t len = 0; 581 int i; 582 583 for (i = 0; i < n; i++) 584 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]); 585 586 buf[len - 1] = '\n'; 587 588 return len; 589 } 590 591 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev, 592 struct device_attribute *attr, char *buf) 593 { 594 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 595 596 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail, 597 data->chip_info->num_oversampling_temp_avail); 598 } 599 600 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev, 601 struct device_attribute *attr, char *buf) 602 { 603 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 604 605 return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail, 606 data->chip_info->num_oversampling_press_avail); 607 } 608 609 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, 610 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0); 611 612 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available, 613 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0); 614 615 static struct attribute *bmp280_attributes[] = { 616 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr, 617 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr, 618 NULL, 619 }; 620 621 static const struct attribute_group bmp280_attrs_group = { 622 .attrs = bmp280_attributes, 623 }; 624 625 static const struct iio_info bmp280_info = { 626 .read_raw = &bmp280_read_raw, 627 .write_raw = &bmp280_write_raw, 628 .attrs = &bmp280_attrs_group, 629 }; 630 631 static int bmp280_chip_config(struct bmp280_data *data) 632 { 633 int ret; 634 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) | 635 BMP280_OSRS_PRESS_X(data->oversampling_press + 1); 636 637 ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS, 638 BMP280_OSRS_TEMP_MASK | 639 BMP280_OSRS_PRESS_MASK | 640 BMP280_MODE_MASK, 641 osrs | BMP280_MODE_NORMAL); 642 if (ret < 0) { 643 dev_err(data->dev, 644 "failed to write ctrl_meas register\n"); 645 return ret; 646 } 647 648 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG, 649 BMP280_FILTER_MASK, 650 BMP280_FILTER_4X); 651 if (ret < 0) { 652 dev_err(data->dev, 653 "failed to write config register\n"); 654 return ret; 655 } 656 657 return ret; 658 } 659 660 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 }; 661 662 static const struct bmp280_chip_info bmp280_chip_info = { 663 .oversampling_temp_avail = bmp280_oversampling_avail, 664 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 665 666 .oversampling_press_avail = bmp280_oversampling_avail, 667 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 668 669 .chip_config = bmp280_chip_config, 670 .read_temp = bmp280_read_temp, 671 .read_press = bmp280_read_press, 672 }; 673 674 static int bme280_chip_config(struct bmp280_data *data) 675 { 676 int ret; 677 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1); 678 679 /* 680 * Oversampling of humidity must be set before oversampling of 681 * temperature/pressure is set to become effective. 682 */ 683 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, 684 BMP280_OSRS_HUMIDITY_MASK, osrs); 685 686 if (ret < 0) 687 return ret; 688 689 return bmp280_chip_config(data); 690 } 691 692 static const struct bmp280_chip_info bme280_chip_info = { 693 .oversampling_temp_avail = bmp280_oversampling_avail, 694 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 695 696 .oversampling_press_avail = bmp280_oversampling_avail, 697 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 698 699 .oversampling_humid_avail = bmp280_oversampling_avail, 700 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail), 701 702 .chip_config = bme280_chip_config, 703 .read_temp = bmp280_read_temp, 704 .read_press = bmp280_read_press, 705 .read_humid = bmp280_read_humid, 706 }; 707 708 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas) 709 { 710 int ret; 711 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 }; 712 unsigned int delay_us; 713 unsigned int ctrl; 714 715 if (data->use_eoc) 716 init_completion(&data->done); 717 718 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas); 719 if (ret) 720 return ret; 721 722 if (data->use_eoc) { 723 /* 724 * If we have a completion interrupt, use it, wait up to 725 * 100ms. The longest conversion time listed is 76.5 ms for 726 * advanced resolution mode. 727 */ 728 ret = wait_for_completion_timeout(&data->done, 729 1 + msecs_to_jiffies(100)); 730 if (!ret) 731 dev_err(data->dev, "timeout waiting for completion\n"); 732 } else { 733 if (ctrl_meas == BMP180_MEAS_TEMP) 734 delay_us = 4500; 735 else 736 delay_us = 737 conversion_time_max[data->oversampling_press]; 738 739 usleep_range(delay_us, delay_us + 1000); 740 } 741 742 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl); 743 if (ret) 744 return ret; 745 746 /* The value of this bit reset to "0" after conversion is complete */ 747 if (ctrl & BMP180_MEAS_SCO) 748 return -EIO; 749 750 return 0; 751 } 752 753 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val) 754 { 755 int ret; 756 __be16 tmp = 0; 757 758 ret = bmp180_measure(data, BMP180_MEAS_TEMP); 759 if (ret) 760 return ret; 761 762 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2); 763 if (ret) 764 return ret; 765 766 *val = be16_to_cpu(tmp); 767 768 return 0; 769 } 770 771 static int bmp180_read_calib(struct bmp280_data *data, 772 struct bmp180_calib *calib) 773 { 774 int ret; 775 int i; 776 __be16 buf[BMP180_REG_CALIB_COUNT / 2]; 777 778 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf, 779 sizeof(buf)); 780 781 if (ret < 0) 782 return ret; 783 784 /* None of the words has the value 0 or 0xFFFF */ 785 for (i = 0; i < ARRAY_SIZE(buf); i++) { 786 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff)) 787 return -EIO; 788 } 789 790 /* Toss the calibration data into the entropy pool */ 791 add_device_randomness(buf, sizeof(buf)); 792 793 calib->AC1 = be16_to_cpu(buf[AC1]); 794 calib->AC2 = be16_to_cpu(buf[AC2]); 795 calib->AC3 = be16_to_cpu(buf[AC3]); 796 calib->AC4 = be16_to_cpu(buf[AC4]); 797 calib->AC5 = be16_to_cpu(buf[AC5]); 798 calib->AC6 = be16_to_cpu(buf[AC6]); 799 calib->B1 = be16_to_cpu(buf[B1]); 800 calib->B2 = be16_to_cpu(buf[B2]); 801 calib->MB = be16_to_cpu(buf[MB]); 802 calib->MC = be16_to_cpu(buf[MC]); 803 calib->MD = be16_to_cpu(buf[MD]); 804 805 return 0; 806 } 807 808 /* 809 * Returns temperature in DegC, resolution is 0.1 DegC. 810 * t_fine carries fine temperature as global value. 811 * 812 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 813 */ 814 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp) 815 { 816 s32 x1, x2; 817 struct bmp180_calib *calib = &data->calib.bmp180; 818 819 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15; 820 x2 = (calib->MC << 11) / (x1 + calib->MD); 821 data->t_fine = x1 + x2; 822 823 return (data->t_fine + 8) >> 4; 824 } 825 826 static int bmp180_read_temp(struct bmp280_data *data, int *val) 827 { 828 int ret; 829 s32 adc_temp, comp_temp; 830 831 ret = bmp180_read_adc_temp(data, &adc_temp); 832 if (ret) 833 return ret; 834 835 comp_temp = bmp180_compensate_temp(data, adc_temp); 836 837 /* 838 * val might be NULL if we're called by the read_press routine, 839 * who only cares about the carry over t_fine value. 840 */ 841 if (val) { 842 *val = comp_temp * 100; 843 return IIO_VAL_INT; 844 } 845 846 return 0; 847 } 848 849 static int bmp180_read_adc_press(struct bmp280_data *data, int *val) 850 { 851 int ret; 852 __be32 tmp = 0; 853 u8 oss = data->oversampling_press; 854 855 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss)); 856 if (ret) 857 return ret; 858 859 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3); 860 if (ret) 861 return ret; 862 863 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss); 864 865 return 0; 866 } 867 868 /* 869 * Returns pressure in Pa, resolution is 1 Pa. 870 * 871 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 872 */ 873 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press) 874 { 875 s32 x1, x2, x3, p; 876 s32 b3, b6; 877 u32 b4, b7; 878 s32 oss = data->oversampling_press; 879 struct bmp180_calib *calib = &data->calib.bmp180; 880 881 b6 = data->t_fine - 4000; 882 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11; 883 x2 = calib->AC2 * b6 >> 11; 884 x3 = x1 + x2; 885 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4; 886 x1 = calib->AC3 * b6 >> 13; 887 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16; 888 x3 = (x1 + x2 + 2) >> 2; 889 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15; 890 b7 = ((u32)adc_press - b3) * (50000 >> oss); 891 if (b7 < 0x80000000) 892 p = (b7 * 2) / b4; 893 else 894 p = (b7 / b4) * 2; 895 896 x1 = (p >> 8) * (p >> 8); 897 x1 = (x1 * 3038) >> 16; 898 x2 = (-7357 * p) >> 16; 899 900 return p + ((x1 + x2 + 3791) >> 4); 901 } 902 903 static int bmp180_read_press(struct bmp280_data *data, 904 int *val, int *val2) 905 { 906 int ret; 907 s32 adc_press; 908 u32 comp_press; 909 910 /* Read and compensate temperature so we get a reading of t_fine. */ 911 ret = bmp180_read_temp(data, NULL); 912 if (ret) 913 return ret; 914 915 ret = bmp180_read_adc_press(data, &adc_press); 916 if (ret) 917 return ret; 918 919 comp_press = bmp180_compensate_press(data, adc_press); 920 921 *val = comp_press; 922 *val2 = 1000; 923 924 return IIO_VAL_FRACTIONAL; 925 } 926 927 static int bmp180_chip_config(struct bmp280_data *data) 928 { 929 return 0; 930 } 931 932 static const int bmp180_oversampling_temp_avail[] = { 1 }; 933 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 }; 934 935 static const struct bmp280_chip_info bmp180_chip_info = { 936 .oversampling_temp_avail = bmp180_oversampling_temp_avail, 937 .num_oversampling_temp_avail = 938 ARRAY_SIZE(bmp180_oversampling_temp_avail), 939 940 .oversampling_press_avail = bmp180_oversampling_press_avail, 941 .num_oversampling_press_avail = 942 ARRAY_SIZE(bmp180_oversampling_press_avail), 943 944 .chip_config = bmp180_chip_config, 945 .read_temp = bmp180_read_temp, 946 .read_press = bmp180_read_press, 947 }; 948 949 static irqreturn_t bmp085_eoc_irq(int irq, void *d) 950 { 951 struct bmp280_data *data = d; 952 953 complete(&data->done); 954 955 return IRQ_HANDLED; 956 } 957 958 static int bmp085_fetch_eoc_irq(struct device *dev, 959 const char *name, 960 int irq, 961 struct bmp280_data *data) 962 { 963 unsigned long irq_trig; 964 int ret; 965 966 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); 967 if (irq_trig != IRQF_TRIGGER_RISING) { 968 dev_err(dev, "non-rising trigger given for EOC interrupt, " 969 "trying to enforce it\n"); 970 irq_trig = IRQF_TRIGGER_RISING; 971 } 972 ret = devm_request_threaded_irq(dev, 973 irq, 974 bmp085_eoc_irq, 975 NULL, 976 irq_trig, 977 name, 978 data); 979 if (ret) { 980 /* Bail out without IRQ but keep the driver in place */ 981 dev_err(dev, "unable to request DRDY IRQ\n"); 982 return 0; 983 } 984 985 data->use_eoc = true; 986 return 0; 987 } 988 989 static void bmp280_pm_disable(void *data) 990 { 991 struct device *dev = data; 992 993 pm_runtime_get_sync(dev); 994 pm_runtime_put_noidle(dev); 995 pm_runtime_disable(dev); 996 } 997 998 static void bmp280_regulators_disable(void *data) 999 { 1000 struct regulator_bulk_data *supplies = data; 1001 1002 regulator_bulk_disable(BMP280_NUM_SUPPLIES, supplies); 1003 } 1004 1005 int bmp280_common_probe(struct device *dev, 1006 struct regmap *regmap, 1007 unsigned int chip, 1008 const char *name, 1009 int irq) 1010 { 1011 int ret; 1012 struct iio_dev *indio_dev; 1013 struct bmp280_data *data; 1014 unsigned int chip_id; 1015 struct gpio_desc *gpiod; 1016 1017 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 1018 if (!indio_dev) 1019 return -ENOMEM; 1020 1021 data = iio_priv(indio_dev); 1022 mutex_init(&data->lock); 1023 data->dev = dev; 1024 1025 indio_dev->dev.parent = dev; 1026 indio_dev->name = name; 1027 indio_dev->channels = bmp280_channels; 1028 indio_dev->info = &bmp280_info; 1029 indio_dev->modes = INDIO_DIRECT_MODE; 1030 1031 switch (chip) { 1032 case BMP180_CHIP_ID: 1033 indio_dev->num_channels = 2; 1034 data->chip_info = &bmp180_chip_info; 1035 data->oversampling_press = ilog2(8); 1036 data->oversampling_temp = ilog2(1); 1037 data->start_up_time = 10000; 1038 break; 1039 case BMP280_CHIP_ID: 1040 indio_dev->num_channels = 2; 1041 data->chip_info = &bmp280_chip_info; 1042 data->oversampling_press = ilog2(16); 1043 data->oversampling_temp = ilog2(2); 1044 data->start_up_time = 2000; 1045 break; 1046 case BME280_CHIP_ID: 1047 indio_dev->num_channels = 3; 1048 data->chip_info = &bme280_chip_info; 1049 data->oversampling_press = ilog2(16); 1050 data->oversampling_humid = ilog2(16); 1051 data->oversampling_temp = ilog2(2); 1052 data->start_up_time = 2000; 1053 break; 1054 default: 1055 return -EINVAL; 1056 } 1057 1058 /* Bring up regulators */ 1059 regulator_bulk_set_supply_names(data->supplies, 1060 bmp280_supply_names, 1061 BMP280_NUM_SUPPLIES); 1062 1063 ret = devm_regulator_bulk_get(dev, 1064 BMP280_NUM_SUPPLIES, data->supplies); 1065 if (ret) { 1066 dev_err(dev, "failed to get regulators\n"); 1067 return ret; 1068 } 1069 1070 ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies); 1071 if (ret) { 1072 dev_err(dev, "failed to enable regulators\n"); 1073 return ret; 1074 } 1075 1076 ret = devm_add_action_or_reset(dev, bmp280_regulators_disable, 1077 data->supplies); 1078 if (ret) 1079 return ret; 1080 1081 /* Wait to make sure we started up properly */ 1082 usleep_range(data->start_up_time, data->start_up_time + 100); 1083 1084 /* Bring chip out of reset if there is an assigned GPIO line */ 1085 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 1086 /* Deassert the signal */ 1087 if (!IS_ERR(gpiod)) { 1088 dev_info(dev, "release reset\n"); 1089 gpiod_set_value(gpiod, 0); 1090 } 1091 1092 data->regmap = regmap; 1093 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id); 1094 if (ret < 0) 1095 return ret; 1096 if (chip_id != chip) { 1097 dev_err(dev, "bad chip id: expected %x got %x\n", 1098 chip, chip_id); 1099 return -EINVAL; 1100 } 1101 1102 ret = data->chip_info->chip_config(data); 1103 if (ret < 0) 1104 return ret; 1105 1106 dev_set_drvdata(dev, indio_dev); 1107 1108 /* 1109 * Some chips have calibration parameters "programmed into the devices' 1110 * non-volatile memory during production". Let's read them out at probe 1111 * time once. They will not change. 1112 */ 1113 if (chip_id == BMP180_CHIP_ID) { 1114 ret = bmp180_read_calib(data, &data->calib.bmp180); 1115 if (ret < 0) { 1116 dev_err(data->dev, 1117 "failed to read calibration coefficients\n"); 1118 return ret; 1119 } 1120 } else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) { 1121 ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id); 1122 if (ret < 0) { 1123 dev_err(data->dev, 1124 "failed to read calibration coefficients\n"); 1125 return ret; 1126 } 1127 } 1128 1129 /* 1130 * Attempt to grab an optional EOC IRQ - only the BMP085 has this 1131 * however as it happens, the BMP085 shares the chip ID of BMP180 1132 * so we look for an IRQ if we have that. 1133 */ 1134 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) { 1135 ret = bmp085_fetch_eoc_irq(dev, name, irq, data); 1136 if (ret) 1137 return ret; 1138 } 1139 1140 /* Enable runtime PM */ 1141 pm_runtime_get_noresume(dev); 1142 pm_runtime_set_active(dev); 1143 pm_runtime_enable(dev); 1144 /* 1145 * Set autosuspend to two orders of magnitude larger than the 1146 * start-up time. 1147 */ 1148 pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10); 1149 pm_runtime_use_autosuspend(dev); 1150 pm_runtime_put(dev); 1151 1152 ret = devm_add_action_or_reset(dev, bmp280_pm_disable, dev); 1153 if (ret) 1154 return ret; 1155 1156 return devm_iio_device_register(dev, indio_dev); 1157 } 1158 EXPORT_SYMBOL(bmp280_common_probe); 1159 1160 #ifdef CONFIG_PM 1161 static int bmp280_runtime_suspend(struct device *dev) 1162 { 1163 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1164 struct bmp280_data *data = iio_priv(indio_dev); 1165 1166 return regulator_bulk_disable(BMP280_NUM_SUPPLIES, data->supplies); 1167 } 1168 1169 static int bmp280_runtime_resume(struct device *dev) 1170 { 1171 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1172 struct bmp280_data *data = iio_priv(indio_dev); 1173 int ret; 1174 1175 ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies); 1176 if (ret) 1177 return ret; 1178 usleep_range(data->start_up_time, data->start_up_time + 100); 1179 return data->chip_info->chip_config(data); 1180 } 1181 #endif /* CONFIG_PM */ 1182 1183 const struct dev_pm_ops bmp280_dev_pm_ops = { 1184 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1185 pm_runtime_force_resume) 1186 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend, 1187 bmp280_runtime_resume, NULL) 1188 }; 1189 EXPORT_SYMBOL(bmp280_dev_pm_ops); 1190 1191 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>"); 1192 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor"); 1193 MODULE_LICENSE("GPL v2"); 1194