1 /* 2 * Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com> 3 * Copyright (c) 2012 Bosch Sensortec GmbH 4 * Copyright (c) 2012 Unixphere AB 5 * Copyright (c) 2014 Intel Corporation 6 * Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org> 7 * 8 * Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 * 14 * Datasheet: 15 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf 16 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf 17 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf 18 */ 19 20 #define pr_fmt(fmt) "bmp280: " fmt 21 22 #include <linux/device.h> 23 #include <linux/module.h> 24 #include <linux/regmap.h> 25 #include <linux/delay.h> 26 #include <linux/iio/iio.h> 27 #include <linux/iio/sysfs.h> 28 #include <linux/gpio/consumer.h> 29 #include <linux/regulator/consumer.h> 30 #include <linux/interrupt.h> 31 #include <linux/irq.h> /* For irq_get_irq_data() */ 32 #include <linux/completion.h> 33 #include <linux/pm_runtime.h> 34 #include <linux/random.h> 35 36 #include "bmp280.h" 37 38 /* 39 * These enums are used for indexing into the array of calibration 40 * coefficients for BMP180. 41 */ 42 enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD }; 43 44 struct bmp180_calib { 45 s16 AC1; 46 s16 AC2; 47 s16 AC3; 48 u16 AC4; 49 u16 AC5; 50 u16 AC6; 51 s16 B1; 52 s16 B2; 53 s16 MB; 54 s16 MC; 55 s16 MD; 56 }; 57 58 /* See datasheet Section 4.2.2. */ 59 struct bmp280_calib { 60 u16 T1; 61 s16 T2; 62 s16 T3; 63 u16 P1; 64 s16 P2; 65 s16 P3; 66 s16 P4; 67 s16 P5; 68 s16 P6; 69 s16 P7; 70 s16 P8; 71 s16 P9; 72 u8 H1; 73 s16 H2; 74 u8 H3; 75 s16 H4; 76 s16 H5; 77 s8 H6; 78 }; 79 80 struct bmp280_data { 81 struct device *dev; 82 struct mutex lock; 83 struct regmap *regmap; 84 struct completion done; 85 bool use_eoc; 86 const struct bmp280_chip_info *chip_info; 87 union { 88 struct bmp180_calib bmp180; 89 struct bmp280_calib bmp280; 90 } calib; 91 struct regulator *vddd; 92 struct regulator *vdda; 93 unsigned int start_up_time; /* in microseconds */ 94 95 /* log of base 2 of oversampling rate */ 96 u8 oversampling_press; 97 u8 oversampling_temp; 98 u8 oversampling_humid; 99 100 /* 101 * Carryover value from temperature conversion, used in pressure 102 * calculation. 103 */ 104 s32 t_fine; 105 }; 106 107 struct bmp280_chip_info { 108 const int *oversampling_temp_avail; 109 int num_oversampling_temp_avail; 110 111 const int *oversampling_press_avail; 112 int num_oversampling_press_avail; 113 114 const int *oversampling_humid_avail; 115 int num_oversampling_humid_avail; 116 117 int (*chip_config)(struct bmp280_data *); 118 int (*read_temp)(struct bmp280_data *, int *); 119 int (*read_press)(struct bmp280_data *, int *, int *); 120 int (*read_humid)(struct bmp280_data *, int *, int *); 121 }; 122 123 /* 124 * These enums are used for indexing into the array of compensation 125 * parameters for BMP280. 126 */ 127 enum { T1, T2, T3 }; 128 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 }; 129 130 static const struct iio_chan_spec bmp280_channels[] = { 131 { 132 .type = IIO_PRESSURE, 133 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 134 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 135 }, 136 { 137 .type = IIO_TEMP, 138 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 139 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 140 }, 141 { 142 .type = IIO_HUMIDITYRELATIVE, 143 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 144 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 145 }, 146 }; 147 148 static int bmp280_read_calib(struct bmp280_data *data, 149 struct bmp280_calib *calib, 150 unsigned int chip) 151 { 152 int ret; 153 unsigned int tmp; 154 struct device *dev = data->dev; 155 __le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2]; 156 __le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2]; 157 158 /* Read temperature calibration values. */ 159 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START, 160 t_buf, BMP280_COMP_TEMP_REG_COUNT); 161 if (ret < 0) { 162 dev_err(data->dev, 163 "failed to read temperature calibration parameters\n"); 164 return ret; 165 } 166 167 calib->T1 = le16_to_cpu(t_buf[T1]); 168 calib->T2 = le16_to_cpu(t_buf[T2]); 169 calib->T3 = le16_to_cpu(t_buf[T3]); 170 171 /* Read pressure calibration values. */ 172 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START, 173 p_buf, BMP280_COMP_PRESS_REG_COUNT); 174 if (ret < 0) { 175 dev_err(data->dev, 176 "failed to read pressure calibration parameters\n"); 177 return ret; 178 } 179 180 calib->P1 = le16_to_cpu(p_buf[P1]); 181 calib->P2 = le16_to_cpu(p_buf[P2]); 182 calib->P3 = le16_to_cpu(p_buf[P3]); 183 calib->P4 = le16_to_cpu(p_buf[P4]); 184 calib->P5 = le16_to_cpu(p_buf[P5]); 185 calib->P6 = le16_to_cpu(p_buf[P6]); 186 calib->P7 = le16_to_cpu(p_buf[P7]); 187 calib->P8 = le16_to_cpu(p_buf[P8]); 188 calib->P9 = le16_to_cpu(p_buf[P9]); 189 190 /* 191 * Read humidity calibration values. 192 * Due to some odd register addressing we cannot just 193 * do a big bulk read. Instead, we have to read each Hx 194 * value separately and sometimes do some bit shifting... 195 * Humidity data is only available on BME280. 196 */ 197 if (chip != BME280_CHIP_ID) 198 return 0; 199 200 ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp); 201 if (ret < 0) { 202 dev_err(dev, "failed to read H1 comp value\n"); 203 return ret; 204 } 205 calib->H1 = tmp; 206 207 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2); 208 if (ret < 0) { 209 dev_err(dev, "failed to read H2 comp value\n"); 210 return ret; 211 } 212 calib->H2 = sign_extend32(le16_to_cpu(tmp), 15); 213 214 ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp); 215 if (ret < 0) { 216 dev_err(dev, "failed to read H3 comp value\n"); 217 return ret; 218 } 219 calib->H3 = tmp; 220 221 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2); 222 if (ret < 0) { 223 dev_err(dev, "failed to read H4 comp value\n"); 224 return ret; 225 } 226 calib->H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) | 227 (be16_to_cpu(tmp) & 0xf), 11); 228 229 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2); 230 if (ret < 0) { 231 dev_err(dev, "failed to read H5 comp value\n"); 232 return ret; 233 } 234 calib->H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11); 235 236 ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp); 237 if (ret < 0) { 238 dev_err(dev, "failed to read H6 comp value\n"); 239 return ret; 240 } 241 calib->H6 = sign_extend32(tmp, 7); 242 243 return 0; 244 } 245 /* 246 * Returns humidity in percent, resolution is 0.01 percent. Output value of 247 * "47445" represents 47445/1024 = 46.333 %RH. 248 * 249 * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula". 250 */ 251 static u32 bmp280_compensate_humidity(struct bmp280_data *data, 252 s32 adc_humidity) 253 { 254 s32 var; 255 struct bmp280_calib *calib = &data->calib.bmp280; 256 257 var = ((s32)data->t_fine) - (s32)76800; 258 var = ((((adc_humidity << 14) - (calib->H4 << 20) - (calib->H5 * var)) 259 + (s32)16384) >> 15) * (((((((var * calib->H6) >> 10) 260 * (((var * (s32)calib->H3) >> 11) + (s32)32768)) >> 10) 261 + (s32)2097152) * calib->H2 + 8192) >> 14); 262 var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4; 263 264 return var >> 12; 265 }; 266 267 /* 268 * Returns temperature in DegC, resolution is 0.01 DegC. Output value of 269 * "5123" equals 51.23 DegC. t_fine carries fine temperature as global 270 * value. 271 * 272 * Taken from datasheet, Section 3.11.3, "Compensation formula". 273 */ 274 static s32 bmp280_compensate_temp(struct bmp280_data *data, 275 s32 adc_temp) 276 { 277 s32 var1, var2; 278 struct bmp280_calib *calib = &data->calib.bmp280; 279 280 var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) * 281 ((s32)calib->T2)) >> 11; 282 var2 = (((((adc_temp >> 4) - ((s32)calib->T1)) * 283 ((adc_temp >> 4) - ((s32)calib->T1))) >> 12) * 284 ((s32)calib->T3)) >> 14; 285 data->t_fine = var1 + var2; 286 287 return (data->t_fine * 5 + 128) >> 8; 288 } 289 290 /* 291 * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 292 * integer bits and 8 fractional bits). Output value of "24674867" 293 * represents 24674867/256 = 96386.2 Pa = 963.862 hPa 294 * 295 * Taken from datasheet, Section 3.11.3, "Compensation formula". 296 */ 297 static u32 bmp280_compensate_press(struct bmp280_data *data, 298 s32 adc_press) 299 { 300 s64 var1, var2, p; 301 struct bmp280_calib *calib = &data->calib.bmp280; 302 303 var1 = ((s64)data->t_fine) - 128000; 304 var2 = var1 * var1 * (s64)calib->P6; 305 var2 += (var1 * (s64)calib->P5) << 17; 306 var2 += ((s64)calib->P4) << 35; 307 var1 = ((var1 * var1 * (s64)calib->P3) >> 8) + 308 ((var1 * (s64)calib->P2) << 12); 309 var1 = ((((s64)1) << 47) + var1) * ((s64)calib->P1) >> 33; 310 311 if (var1 == 0) 312 return 0; 313 314 p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125; 315 p = div64_s64(p, var1); 316 var1 = (((s64)calib->P9) * (p >> 13) * (p >> 13)) >> 25; 317 var2 = ((s64)(calib->P8) * p) >> 19; 318 p = ((p + var1 + var2) >> 8) + (((s64)calib->P7) << 4); 319 320 return (u32)p; 321 } 322 323 static int bmp280_read_temp(struct bmp280_data *data, 324 int *val) 325 { 326 int ret; 327 __be32 tmp = 0; 328 s32 adc_temp, comp_temp; 329 330 ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, 331 (u8 *) &tmp, 3); 332 if (ret < 0) { 333 dev_err(data->dev, "failed to read temperature\n"); 334 return ret; 335 } 336 337 adc_temp = be32_to_cpu(tmp) >> 12; 338 if (adc_temp == BMP280_TEMP_SKIPPED) { 339 /* reading was skipped */ 340 dev_err(data->dev, "reading temperature skipped\n"); 341 return -EIO; 342 } 343 comp_temp = bmp280_compensate_temp(data, adc_temp); 344 345 /* 346 * val might be NULL if we're called by the read_press routine, 347 * who only cares about the carry over t_fine value. 348 */ 349 if (val) { 350 *val = comp_temp * 10; 351 return IIO_VAL_INT; 352 } 353 354 return 0; 355 } 356 357 static int bmp280_read_press(struct bmp280_data *data, 358 int *val, int *val2) 359 { 360 int ret; 361 __be32 tmp = 0; 362 s32 adc_press; 363 u32 comp_press; 364 365 /* Read and compensate temperature so we get a reading of t_fine. */ 366 ret = bmp280_read_temp(data, NULL); 367 if (ret < 0) 368 return ret; 369 370 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, 371 (u8 *) &tmp, 3); 372 if (ret < 0) { 373 dev_err(data->dev, "failed to read pressure\n"); 374 return ret; 375 } 376 377 adc_press = be32_to_cpu(tmp) >> 12; 378 if (adc_press == BMP280_PRESS_SKIPPED) { 379 /* reading was skipped */ 380 dev_err(data->dev, "reading pressure skipped\n"); 381 return -EIO; 382 } 383 comp_press = bmp280_compensate_press(data, adc_press); 384 385 *val = comp_press; 386 *val2 = 256000; 387 388 return IIO_VAL_FRACTIONAL; 389 } 390 391 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2) 392 { 393 int ret; 394 __be16 tmp = 0; 395 s32 adc_humidity; 396 u32 comp_humidity; 397 398 /* Read and compensate temperature so we get a reading of t_fine. */ 399 ret = bmp280_read_temp(data, NULL); 400 if (ret < 0) 401 return ret; 402 403 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, 404 (u8 *) &tmp, 2); 405 if (ret < 0) { 406 dev_err(data->dev, "failed to read humidity\n"); 407 return ret; 408 } 409 410 adc_humidity = be16_to_cpu(tmp); 411 if (adc_humidity == BMP280_HUMIDITY_SKIPPED) { 412 /* reading was skipped */ 413 dev_err(data->dev, "reading humidity skipped\n"); 414 return -EIO; 415 } 416 comp_humidity = bmp280_compensate_humidity(data, adc_humidity); 417 418 *val = comp_humidity; 419 *val2 = 1024; 420 421 return IIO_VAL_FRACTIONAL; 422 } 423 424 static int bmp280_read_raw(struct iio_dev *indio_dev, 425 struct iio_chan_spec const *chan, 426 int *val, int *val2, long mask) 427 { 428 int ret; 429 struct bmp280_data *data = iio_priv(indio_dev); 430 431 pm_runtime_get_sync(data->dev); 432 mutex_lock(&data->lock); 433 434 switch (mask) { 435 case IIO_CHAN_INFO_PROCESSED: 436 switch (chan->type) { 437 case IIO_HUMIDITYRELATIVE: 438 ret = data->chip_info->read_humid(data, val, val2); 439 break; 440 case IIO_PRESSURE: 441 ret = data->chip_info->read_press(data, val, val2); 442 break; 443 case IIO_TEMP: 444 ret = data->chip_info->read_temp(data, val); 445 break; 446 default: 447 ret = -EINVAL; 448 break; 449 } 450 break; 451 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 452 switch (chan->type) { 453 case IIO_HUMIDITYRELATIVE: 454 *val = 1 << data->oversampling_humid; 455 ret = IIO_VAL_INT; 456 break; 457 case IIO_PRESSURE: 458 *val = 1 << data->oversampling_press; 459 ret = IIO_VAL_INT; 460 break; 461 case IIO_TEMP: 462 *val = 1 << data->oversampling_temp; 463 ret = IIO_VAL_INT; 464 break; 465 default: 466 ret = -EINVAL; 467 break; 468 } 469 break; 470 default: 471 ret = -EINVAL; 472 break; 473 } 474 475 mutex_unlock(&data->lock); 476 pm_runtime_mark_last_busy(data->dev); 477 pm_runtime_put_autosuspend(data->dev); 478 479 return ret; 480 } 481 482 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data, 483 int val) 484 { 485 int i; 486 const int *avail = data->chip_info->oversampling_humid_avail; 487 const int n = data->chip_info->num_oversampling_humid_avail; 488 489 for (i = 0; i < n; i++) { 490 if (avail[i] == val) { 491 data->oversampling_humid = ilog2(val); 492 493 return data->chip_info->chip_config(data); 494 } 495 } 496 return -EINVAL; 497 } 498 499 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data, 500 int val) 501 { 502 int i; 503 const int *avail = data->chip_info->oversampling_temp_avail; 504 const int n = data->chip_info->num_oversampling_temp_avail; 505 506 for (i = 0; i < n; i++) { 507 if (avail[i] == val) { 508 data->oversampling_temp = ilog2(val); 509 510 return data->chip_info->chip_config(data); 511 } 512 } 513 return -EINVAL; 514 } 515 516 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data, 517 int val) 518 { 519 int i; 520 const int *avail = data->chip_info->oversampling_press_avail; 521 const int n = data->chip_info->num_oversampling_press_avail; 522 523 for (i = 0; i < n; i++) { 524 if (avail[i] == val) { 525 data->oversampling_press = ilog2(val); 526 527 return data->chip_info->chip_config(data); 528 } 529 } 530 return -EINVAL; 531 } 532 533 static int bmp280_write_raw(struct iio_dev *indio_dev, 534 struct iio_chan_spec const *chan, 535 int val, int val2, long mask) 536 { 537 int ret = 0; 538 struct bmp280_data *data = iio_priv(indio_dev); 539 540 switch (mask) { 541 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 542 pm_runtime_get_sync(data->dev); 543 mutex_lock(&data->lock); 544 switch (chan->type) { 545 case IIO_HUMIDITYRELATIVE: 546 ret = bmp280_write_oversampling_ratio_humid(data, val); 547 break; 548 case IIO_PRESSURE: 549 ret = bmp280_write_oversampling_ratio_press(data, val); 550 break; 551 case IIO_TEMP: 552 ret = bmp280_write_oversampling_ratio_temp(data, val); 553 break; 554 default: 555 ret = -EINVAL; 556 break; 557 } 558 mutex_unlock(&data->lock); 559 pm_runtime_mark_last_busy(data->dev); 560 pm_runtime_put_autosuspend(data->dev); 561 break; 562 default: 563 return -EINVAL; 564 } 565 566 return ret; 567 } 568 569 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n) 570 { 571 size_t len = 0; 572 int i; 573 574 for (i = 0; i < n; i++) 575 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]); 576 577 buf[len - 1] = '\n'; 578 579 return len; 580 } 581 582 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev, 583 struct device_attribute *attr, char *buf) 584 { 585 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 586 587 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail, 588 data->chip_info->num_oversampling_temp_avail); 589 } 590 591 static ssize_t bmp280_show_press_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_press_avail, 597 data->chip_info->num_oversampling_press_avail); 598 } 599 600 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, 601 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0); 602 603 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available, 604 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0); 605 606 static struct attribute *bmp280_attributes[] = { 607 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr, 608 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr, 609 NULL, 610 }; 611 612 static const struct attribute_group bmp280_attrs_group = { 613 .attrs = bmp280_attributes, 614 }; 615 616 static const struct iio_info bmp280_info = { 617 .read_raw = &bmp280_read_raw, 618 .write_raw = &bmp280_write_raw, 619 .attrs = &bmp280_attrs_group, 620 }; 621 622 static int bmp280_chip_config(struct bmp280_data *data) 623 { 624 int ret; 625 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) | 626 BMP280_OSRS_PRESS_X(data->oversampling_press + 1); 627 628 ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS, 629 BMP280_OSRS_TEMP_MASK | 630 BMP280_OSRS_PRESS_MASK | 631 BMP280_MODE_MASK, 632 osrs | BMP280_MODE_NORMAL); 633 if (ret < 0) { 634 dev_err(data->dev, 635 "failed to write ctrl_meas register\n"); 636 return ret; 637 } 638 639 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG, 640 BMP280_FILTER_MASK, 641 BMP280_FILTER_4X); 642 if (ret < 0) { 643 dev_err(data->dev, 644 "failed to write config register\n"); 645 return ret; 646 } 647 648 return ret; 649 } 650 651 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 }; 652 653 static const struct bmp280_chip_info bmp280_chip_info = { 654 .oversampling_temp_avail = bmp280_oversampling_avail, 655 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 656 657 .oversampling_press_avail = bmp280_oversampling_avail, 658 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 659 660 .chip_config = bmp280_chip_config, 661 .read_temp = bmp280_read_temp, 662 .read_press = bmp280_read_press, 663 }; 664 665 static int bme280_chip_config(struct bmp280_data *data) 666 { 667 int ret; 668 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1); 669 670 /* 671 * Oversampling of humidity must be set before oversampling of 672 * temperature/pressure is set to become effective. 673 */ 674 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, 675 BMP280_OSRS_HUMIDITY_MASK, osrs); 676 677 if (ret < 0) 678 return ret; 679 680 return bmp280_chip_config(data); 681 } 682 683 static const struct bmp280_chip_info bme280_chip_info = { 684 .oversampling_temp_avail = bmp280_oversampling_avail, 685 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 686 687 .oversampling_press_avail = bmp280_oversampling_avail, 688 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 689 690 .oversampling_humid_avail = bmp280_oversampling_avail, 691 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail), 692 693 .chip_config = bme280_chip_config, 694 .read_temp = bmp280_read_temp, 695 .read_press = bmp280_read_press, 696 .read_humid = bmp280_read_humid, 697 }; 698 699 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas) 700 { 701 int ret; 702 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 }; 703 unsigned int delay_us; 704 unsigned int ctrl; 705 706 if (data->use_eoc) 707 init_completion(&data->done); 708 709 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas); 710 if (ret) 711 return ret; 712 713 if (data->use_eoc) { 714 /* 715 * If we have a completion interrupt, use it, wait up to 716 * 100ms. The longest conversion time listed is 76.5 ms for 717 * advanced resolution mode. 718 */ 719 ret = wait_for_completion_timeout(&data->done, 720 1 + msecs_to_jiffies(100)); 721 if (!ret) 722 dev_err(data->dev, "timeout waiting for completion\n"); 723 } else { 724 if (ctrl_meas == BMP180_MEAS_TEMP) 725 delay_us = 4500; 726 else 727 delay_us = 728 conversion_time_max[data->oversampling_press]; 729 730 usleep_range(delay_us, delay_us + 1000); 731 } 732 733 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl); 734 if (ret) 735 return ret; 736 737 /* The value of this bit reset to "0" after conversion is complete */ 738 if (ctrl & BMP180_MEAS_SCO) 739 return -EIO; 740 741 return 0; 742 } 743 744 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val) 745 { 746 int ret; 747 __be16 tmp = 0; 748 749 ret = bmp180_measure(data, BMP180_MEAS_TEMP); 750 if (ret) 751 return ret; 752 753 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2); 754 if (ret) 755 return ret; 756 757 *val = be16_to_cpu(tmp); 758 759 return 0; 760 } 761 762 static int bmp180_read_calib(struct bmp280_data *data, 763 struct bmp180_calib *calib) 764 { 765 int ret; 766 int i; 767 __be16 buf[BMP180_REG_CALIB_COUNT / 2]; 768 769 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf, 770 sizeof(buf)); 771 772 if (ret < 0) 773 return ret; 774 775 /* None of the words has the value 0 or 0xFFFF */ 776 for (i = 0; i < ARRAY_SIZE(buf); i++) { 777 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff)) 778 return -EIO; 779 } 780 781 /* Toss the calibration data into the entropy pool */ 782 add_device_randomness(buf, sizeof(buf)); 783 784 calib->AC1 = be16_to_cpu(buf[AC1]); 785 calib->AC2 = be16_to_cpu(buf[AC2]); 786 calib->AC3 = be16_to_cpu(buf[AC3]); 787 calib->AC4 = be16_to_cpu(buf[AC4]); 788 calib->AC5 = be16_to_cpu(buf[AC5]); 789 calib->AC6 = be16_to_cpu(buf[AC6]); 790 calib->B1 = be16_to_cpu(buf[B1]); 791 calib->B2 = be16_to_cpu(buf[B2]); 792 calib->MB = be16_to_cpu(buf[MB]); 793 calib->MC = be16_to_cpu(buf[MC]); 794 calib->MD = be16_to_cpu(buf[MD]); 795 796 return 0; 797 } 798 799 /* 800 * Returns temperature in DegC, resolution is 0.1 DegC. 801 * t_fine carries fine temperature as global value. 802 * 803 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 804 */ 805 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp) 806 { 807 s32 x1, x2; 808 struct bmp180_calib *calib = &data->calib.bmp180; 809 810 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15; 811 x2 = (calib->MC << 11) / (x1 + calib->MD); 812 data->t_fine = x1 + x2; 813 814 return (data->t_fine + 8) >> 4; 815 } 816 817 static int bmp180_read_temp(struct bmp280_data *data, int *val) 818 { 819 int ret; 820 s32 adc_temp, comp_temp; 821 822 ret = bmp180_read_adc_temp(data, &adc_temp); 823 if (ret) 824 return ret; 825 826 comp_temp = bmp180_compensate_temp(data, adc_temp); 827 828 /* 829 * val might be NULL if we're called by the read_press routine, 830 * who only cares about the carry over t_fine value. 831 */ 832 if (val) { 833 *val = comp_temp * 100; 834 return IIO_VAL_INT; 835 } 836 837 return 0; 838 } 839 840 static int bmp180_read_adc_press(struct bmp280_data *data, int *val) 841 { 842 int ret; 843 __be32 tmp = 0; 844 u8 oss = data->oversampling_press; 845 846 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss)); 847 if (ret) 848 return ret; 849 850 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3); 851 if (ret) 852 return ret; 853 854 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss); 855 856 return 0; 857 } 858 859 /* 860 * Returns pressure in Pa, resolution is 1 Pa. 861 * 862 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 863 */ 864 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press) 865 { 866 s32 x1, x2, x3, p; 867 s32 b3, b6; 868 u32 b4, b7; 869 s32 oss = data->oversampling_press; 870 struct bmp180_calib *calib = &data->calib.bmp180; 871 872 b6 = data->t_fine - 4000; 873 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11; 874 x2 = calib->AC2 * b6 >> 11; 875 x3 = x1 + x2; 876 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4; 877 x1 = calib->AC3 * b6 >> 13; 878 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16; 879 x3 = (x1 + x2 + 2) >> 2; 880 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15; 881 b7 = ((u32)adc_press - b3) * (50000 >> oss); 882 if (b7 < 0x80000000) 883 p = (b7 * 2) / b4; 884 else 885 p = (b7 / b4) * 2; 886 887 x1 = (p >> 8) * (p >> 8); 888 x1 = (x1 * 3038) >> 16; 889 x2 = (-7357 * p) >> 16; 890 891 return p + ((x1 + x2 + 3791) >> 4); 892 } 893 894 static int bmp180_read_press(struct bmp280_data *data, 895 int *val, int *val2) 896 { 897 int ret; 898 s32 adc_press; 899 u32 comp_press; 900 901 /* Read and compensate temperature so we get a reading of t_fine. */ 902 ret = bmp180_read_temp(data, NULL); 903 if (ret) 904 return ret; 905 906 ret = bmp180_read_adc_press(data, &adc_press); 907 if (ret) 908 return ret; 909 910 comp_press = bmp180_compensate_press(data, adc_press); 911 912 *val = comp_press; 913 *val2 = 1000; 914 915 return IIO_VAL_FRACTIONAL; 916 } 917 918 static int bmp180_chip_config(struct bmp280_data *data) 919 { 920 return 0; 921 } 922 923 static const int bmp180_oversampling_temp_avail[] = { 1 }; 924 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 }; 925 926 static const struct bmp280_chip_info bmp180_chip_info = { 927 .oversampling_temp_avail = bmp180_oversampling_temp_avail, 928 .num_oversampling_temp_avail = 929 ARRAY_SIZE(bmp180_oversampling_temp_avail), 930 931 .oversampling_press_avail = bmp180_oversampling_press_avail, 932 .num_oversampling_press_avail = 933 ARRAY_SIZE(bmp180_oversampling_press_avail), 934 935 .chip_config = bmp180_chip_config, 936 .read_temp = bmp180_read_temp, 937 .read_press = bmp180_read_press, 938 }; 939 940 static irqreturn_t bmp085_eoc_irq(int irq, void *d) 941 { 942 struct bmp280_data *data = d; 943 944 complete(&data->done); 945 946 return IRQ_HANDLED; 947 } 948 949 static int bmp085_fetch_eoc_irq(struct device *dev, 950 const char *name, 951 int irq, 952 struct bmp280_data *data) 953 { 954 unsigned long irq_trig; 955 int ret; 956 957 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); 958 if (irq_trig != IRQF_TRIGGER_RISING) { 959 dev_err(dev, "non-rising trigger given for EOC interrupt, " 960 "trying to enforce it\n"); 961 irq_trig = IRQF_TRIGGER_RISING; 962 } 963 ret = devm_request_threaded_irq(dev, 964 irq, 965 bmp085_eoc_irq, 966 NULL, 967 irq_trig, 968 name, 969 data); 970 if (ret) { 971 /* Bail out without IRQ but keep the driver in place */ 972 dev_err(dev, "unable to request DRDY IRQ\n"); 973 return 0; 974 } 975 976 data->use_eoc = true; 977 return 0; 978 } 979 980 int bmp280_common_probe(struct device *dev, 981 struct regmap *regmap, 982 unsigned int chip, 983 const char *name, 984 int irq) 985 { 986 int ret; 987 struct iio_dev *indio_dev; 988 struct bmp280_data *data; 989 unsigned int chip_id; 990 struct gpio_desc *gpiod; 991 992 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 993 if (!indio_dev) 994 return -ENOMEM; 995 996 data = iio_priv(indio_dev); 997 mutex_init(&data->lock); 998 data->dev = dev; 999 1000 indio_dev->dev.parent = dev; 1001 indio_dev->name = name; 1002 indio_dev->channels = bmp280_channels; 1003 indio_dev->info = &bmp280_info; 1004 indio_dev->modes = INDIO_DIRECT_MODE; 1005 1006 switch (chip) { 1007 case BMP180_CHIP_ID: 1008 indio_dev->num_channels = 2; 1009 data->chip_info = &bmp180_chip_info; 1010 data->oversampling_press = ilog2(8); 1011 data->oversampling_temp = ilog2(1); 1012 data->start_up_time = 10000; 1013 break; 1014 case BMP280_CHIP_ID: 1015 indio_dev->num_channels = 2; 1016 data->chip_info = &bmp280_chip_info; 1017 data->oversampling_press = ilog2(16); 1018 data->oversampling_temp = ilog2(2); 1019 data->start_up_time = 2000; 1020 break; 1021 case BME280_CHIP_ID: 1022 indio_dev->num_channels = 3; 1023 data->chip_info = &bme280_chip_info; 1024 data->oversampling_press = ilog2(16); 1025 data->oversampling_humid = ilog2(16); 1026 data->oversampling_temp = ilog2(2); 1027 data->start_up_time = 2000; 1028 break; 1029 default: 1030 return -EINVAL; 1031 } 1032 1033 /* Bring up regulators */ 1034 data->vddd = devm_regulator_get(dev, "vddd"); 1035 if (IS_ERR(data->vddd)) { 1036 dev_err(dev, "failed to get VDDD regulator\n"); 1037 return PTR_ERR(data->vddd); 1038 } 1039 ret = regulator_enable(data->vddd); 1040 if (ret) { 1041 dev_err(dev, "failed to enable VDDD regulator\n"); 1042 return ret; 1043 } 1044 data->vdda = devm_regulator_get(dev, "vdda"); 1045 if (IS_ERR(data->vdda)) { 1046 dev_err(dev, "failed to get VDDA regulator\n"); 1047 ret = PTR_ERR(data->vdda); 1048 goto out_disable_vddd; 1049 } 1050 ret = regulator_enable(data->vdda); 1051 if (ret) { 1052 dev_err(dev, "failed to enable VDDA regulator\n"); 1053 goto out_disable_vddd; 1054 } 1055 /* Wait to make sure we started up properly */ 1056 usleep_range(data->start_up_time, data->start_up_time + 100); 1057 1058 /* Bring chip out of reset if there is an assigned GPIO line */ 1059 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 1060 /* Deassert the signal */ 1061 if (!IS_ERR(gpiod)) { 1062 dev_info(dev, "release reset\n"); 1063 gpiod_set_value(gpiod, 0); 1064 } 1065 1066 data->regmap = regmap; 1067 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id); 1068 if (ret < 0) 1069 goto out_disable_vdda; 1070 if (chip_id != chip) { 1071 dev_err(dev, "bad chip id: expected %x got %x\n", 1072 chip, chip_id); 1073 ret = -EINVAL; 1074 goto out_disable_vdda; 1075 } 1076 1077 ret = data->chip_info->chip_config(data); 1078 if (ret < 0) 1079 goto out_disable_vdda; 1080 1081 dev_set_drvdata(dev, indio_dev); 1082 1083 /* 1084 * Some chips have calibration parameters "programmed into the devices' 1085 * non-volatile memory during production". Let's read them out at probe 1086 * time once. They will not change. 1087 */ 1088 if (chip_id == BMP180_CHIP_ID) { 1089 ret = bmp180_read_calib(data, &data->calib.bmp180); 1090 if (ret < 0) { 1091 dev_err(data->dev, 1092 "failed to read calibration coefficients\n"); 1093 goto out_disable_vdda; 1094 } 1095 } else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) { 1096 ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id); 1097 if (ret < 0) { 1098 dev_err(data->dev, 1099 "failed to read calibration coefficients\n"); 1100 goto out_disable_vdda; 1101 } 1102 } 1103 1104 /* 1105 * Attempt to grab an optional EOC IRQ - only the BMP085 has this 1106 * however as it happens, the BMP085 shares the chip ID of BMP180 1107 * so we look for an IRQ if we have that. 1108 */ 1109 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) { 1110 ret = bmp085_fetch_eoc_irq(dev, name, irq, data); 1111 if (ret) 1112 goto out_disable_vdda; 1113 } 1114 1115 /* Enable runtime PM */ 1116 pm_runtime_get_noresume(dev); 1117 pm_runtime_set_active(dev); 1118 pm_runtime_enable(dev); 1119 /* 1120 * Set autosuspend to two orders of magnitude larger than the 1121 * start-up time. 1122 */ 1123 pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10); 1124 pm_runtime_use_autosuspend(dev); 1125 pm_runtime_put(dev); 1126 1127 ret = iio_device_register(indio_dev); 1128 if (ret) 1129 goto out_runtime_pm_disable; 1130 1131 1132 return 0; 1133 1134 out_runtime_pm_disable: 1135 pm_runtime_get_sync(data->dev); 1136 pm_runtime_put_noidle(data->dev); 1137 pm_runtime_disable(data->dev); 1138 out_disable_vdda: 1139 regulator_disable(data->vdda); 1140 out_disable_vddd: 1141 regulator_disable(data->vddd); 1142 return ret; 1143 } 1144 EXPORT_SYMBOL(bmp280_common_probe); 1145 1146 int bmp280_common_remove(struct device *dev) 1147 { 1148 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1149 struct bmp280_data *data = iio_priv(indio_dev); 1150 1151 iio_device_unregister(indio_dev); 1152 pm_runtime_get_sync(data->dev); 1153 pm_runtime_put_noidle(data->dev); 1154 pm_runtime_disable(data->dev); 1155 regulator_disable(data->vdda); 1156 regulator_disable(data->vddd); 1157 return 0; 1158 } 1159 EXPORT_SYMBOL(bmp280_common_remove); 1160 1161 #ifdef CONFIG_PM 1162 static int bmp280_runtime_suspend(struct device *dev) 1163 { 1164 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1165 struct bmp280_data *data = iio_priv(indio_dev); 1166 int ret; 1167 1168 ret = regulator_disable(data->vdda); 1169 if (ret) 1170 return ret; 1171 return regulator_disable(data->vddd); 1172 } 1173 1174 static int bmp280_runtime_resume(struct device *dev) 1175 { 1176 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1177 struct bmp280_data *data = iio_priv(indio_dev); 1178 int ret; 1179 1180 ret = regulator_enable(data->vddd); 1181 if (ret) 1182 return ret; 1183 ret = regulator_enable(data->vdda); 1184 if (ret) 1185 return ret; 1186 usleep_range(data->start_up_time, data->start_up_time + 100); 1187 return data->chip_info->chip_config(data); 1188 } 1189 #endif /* CONFIG_PM */ 1190 1191 const struct dev_pm_ops bmp280_dev_pm_ops = { 1192 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1193 pm_runtime_force_resume) 1194 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend, 1195 bmp280_runtime_resume, NULL) 1196 }; 1197 EXPORT_SYMBOL(bmp280_dev_pm_ops); 1198 1199 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>"); 1200 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor"); 1201 MODULE_LICENSE("GPL v2"); 1202