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 struct bmp280_data { 59 struct device *dev; 60 struct mutex lock; 61 struct regmap *regmap; 62 struct completion done; 63 bool use_eoc; 64 const struct bmp280_chip_info *chip_info; 65 struct bmp180_calib calib; 66 struct regulator *vddd; 67 struct regulator *vdda; 68 unsigned int start_up_time; /* in microseconds */ 69 70 /* log of base 2 of oversampling rate */ 71 u8 oversampling_press; 72 u8 oversampling_temp; 73 u8 oversampling_humid; 74 75 /* 76 * Carryover value from temperature conversion, used in pressure 77 * calculation. 78 */ 79 s32 t_fine; 80 }; 81 82 struct bmp280_chip_info { 83 const int *oversampling_temp_avail; 84 int num_oversampling_temp_avail; 85 86 const int *oversampling_press_avail; 87 int num_oversampling_press_avail; 88 89 const int *oversampling_humid_avail; 90 int num_oversampling_humid_avail; 91 92 int (*chip_config)(struct bmp280_data *); 93 int (*read_temp)(struct bmp280_data *, int *); 94 int (*read_press)(struct bmp280_data *, int *, int *); 95 int (*read_humid)(struct bmp280_data *, int *, int *); 96 }; 97 98 /* 99 * These enums are used for indexing into the array of compensation 100 * parameters for BMP280. 101 */ 102 enum { T1, T2, T3 }; 103 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 }; 104 105 static const struct iio_chan_spec bmp280_channels[] = { 106 { 107 .type = IIO_PRESSURE, 108 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 109 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 110 }, 111 { 112 .type = IIO_TEMP, 113 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 114 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 115 }, 116 { 117 .type = IIO_HUMIDITYRELATIVE, 118 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 119 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 120 }, 121 }; 122 123 /* 124 * Returns humidity in percent, resolution is 0.01 percent. Output value of 125 * "47445" represents 47445/1024 = 46.333 %RH. 126 * 127 * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula". 128 */ 129 130 static u32 bmp280_compensate_humidity(struct bmp280_data *data, 131 s32 adc_humidity) 132 { 133 struct device *dev = data->dev; 134 unsigned int H1, H3, tmp; 135 int H2, H4, H5, H6, ret, var; 136 137 ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &H1); 138 if (ret < 0) { 139 dev_err(dev, "failed to read H1 comp value\n"); 140 return ret; 141 } 142 143 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2); 144 if (ret < 0) { 145 dev_err(dev, "failed to read H2 comp value\n"); 146 return ret; 147 } 148 H2 = sign_extend32(le16_to_cpu(tmp), 15); 149 150 ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &H3); 151 if (ret < 0) { 152 dev_err(dev, "failed to read H3 comp value\n"); 153 return ret; 154 } 155 156 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2); 157 if (ret < 0) { 158 dev_err(dev, "failed to read H4 comp value\n"); 159 return ret; 160 } 161 H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) | 162 (be16_to_cpu(tmp) & 0xf), 11); 163 164 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2); 165 if (ret < 0) { 166 dev_err(dev, "failed to read H5 comp value\n"); 167 return ret; 168 } 169 H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11); 170 171 ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp); 172 if (ret < 0) { 173 dev_err(dev, "failed to read H6 comp value\n"); 174 return ret; 175 } 176 H6 = sign_extend32(tmp, 7); 177 178 var = ((s32)data->t_fine) - (s32)76800; 179 var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var)) 180 + (s32)16384) >> 15) * (((((((var * H6) >> 10) 181 * (((var * (s32)H3) >> 11) + (s32)32768)) >> 10) 182 + (s32)2097152) * H2 + 8192) >> 14); 183 var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)H1) >> 4; 184 185 return var >> 12; 186 }; 187 188 /* 189 * Returns temperature in DegC, resolution is 0.01 DegC. Output value of 190 * "5123" equals 51.23 DegC. t_fine carries fine temperature as global 191 * value. 192 * 193 * Taken from datasheet, Section 3.11.3, "Compensation formula". 194 */ 195 static s32 bmp280_compensate_temp(struct bmp280_data *data, 196 s32 adc_temp) 197 { 198 int ret; 199 s32 var1, var2; 200 __le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2]; 201 202 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START, 203 buf, BMP280_COMP_TEMP_REG_COUNT); 204 if (ret < 0) { 205 dev_err(data->dev, 206 "failed to read temperature calibration parameters\n"); 207 return ret; 208 } 209 210 /* 211 * The double casts are necessary because le16_to_cpu returns an 212 * unsigned 16-bit value. Casting that value directly to a 213 * signed 32-bit will not do proper sign extension. 214 * 215 * Conversely, T1 and P1 are unsigned values, so they can be 216 * cast straight to the larger type. 217 */ 218 var1 = (((adc_temp >> 3) - ((s32)le16_to_cpu(buf[T1]) << 1)) * 219 ((s32)(s16)le16_to_cpu(buf[T2]))) >> 11; 220 var2 = (((((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1]))) * 221 ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) * 222 ((s32)(s16)le16_to_cpu(buf[T3]))) >> 14; 223 data->t_fine = var1 + var2; 224 225 return (data->t_fine * 5 + 128) >> 8; 226 } 227 228 /* 229 * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 230 * integer bits and 8 fractional bits). Output value of "24674867" 231 * represents 24674867/256 = 96386.2 Pa = 963.862 hPa 232 * 233 * Taken from datasheet, Section 3.11.3, "Compensation formula". 234 */ 235 static u32 bmp280_compensate_press(struct bmp280_data *data, 236 s32 adc_press) 237 { 238 int ret; 239 s64 var1, var2, p; 240 __le16 buf[BMP280_COMP_PRESS_REG_COUNT / 2]; 241 242 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START, 243 buf, BMP280_COMP_PRESS_REG_COUNT); 244 if (ret < 0) { 245 dev_err(data->dev, 246 "failed to read pressure calibration parameters\n"); 247 return ret; 248 } 249 250 var1 = ((s64)data->t_fine) - 128000; 251 var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]); 252 var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17; 253 var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35; 254 var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) + 255 ((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12); 256 var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33; 257 258 if (var1 == 0) 259 return 0; 260 261 p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125; 262 p = div64_s64(p, var1); 263 var1 = (((s64)(s16)le16_to_cpu(buf[P9])) * (p >> 13) * (p >> 13)) >> 25; 264 var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19; 265 p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4); 266 267 return (u32)p; 268 } 269 270 static int bmp280_read_temp(struct bmp280_data *data, 271 int *val) 272 { 273 int ret; 274 __be32 tmp = 0; 275 s32 adc_temp, comp_temp; 276 277 ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, 278 (u8 *) &tmp, 3); 279 if (ret < 0) { 280 dev_err(data->dev, "failed to read temperature\n"); 281 return ret; 282 } 283 284 adc_temp = be32_to_cpu(tmp) >> 12; 285 if (adc_temp == BMP280_TEMP_SKIPPED) { 286 /* reading was skipped */ 287 dev_err(data->dev, "reading temperature skipped\n"); 288 return -EIO; 289 } 290 comp_temp = bmp280_compensate_temp(data, adc_temp); 291 292 /* 293 * val might be NULL if we're called by the read_press routine, 294 * who only cares about the carry over t_fine value. 295 */ 296 if (val) { 297 *val = comp_temp * 10; 298 return IIO_VAL_INT; 299 } 300 301 return 0; 302 } 303 304 static int bmp280_read_press(struct bmp280_data *data, 305 int *val, int *val2) 306 { 307 int ret; 308 __be32 tmp = 0; 309 s32 adc_press; 310 u32 comp_press; 311 312 /* Read and compensate temperature so we get a reading of t_fine. */ 313 ret = bmp280_read_temp(data, NULL); 314 if (ret < 0) 315 return ret; 316 317 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, 318 (u8 *) &tmp, 3); 319 if (ret < 0) { 320 dev_err(data->dev, "failed to read pressure\n"); 321 return ret; 322 } 323 324 adc_press = be32_to_cpu(tmp) >> 12; 325 if (adc_press == BMP280_PRESS_SKIPPED) { 326 /* reading was skipped */ 327 dev_err(data->dev, "reading pressure skipped\n"); 328 return -EIO; 329 } 330 comp_press = bmp280_compensate_press(data, adc_press); 331 332 *val = comp_press; 333 *val2 = 256000; 334 335 return IIO_VAL_FRACTIONAL; 336 } 337 338 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2) 339 { 340 int ret; 341 __be16 tmp = 0; 342 s32 adc_humidity; 343 u32 comp_humidity; 344 345 /* Read and compensate temperature so we get a reading of t_fine. */ 346 ret = bmp280_read_temp(data, NULL); 347 if (ret < 0) 348 return ret; 349 350 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, 351 (u8 *) &tmp, 2); 352 if (ret < 0) { 353 dev_err(data->dev, "failed to read humidity\n"); 354 return ret; 355 } 356 357 adc_humidity = be16_to_cpu(tmp); 358 if (adc_humidity == BMP280_HUMIDITY_SKIPPED) { 359 /* reading was skipped */ 360 dev_err(data->dev, "reading humidity skipped\n"); 361 return -EIO; 362 } 363 comp_humidity = bmp280_compensate_humidity(data, adc_humidity); 364 365 *val = comp_humidity; 366 *val2 = 1024; 367 368 return IIO_VAL_FRACTIONAL; 369 } 370 371 static int bmp280_read_raw(struct iio_dev *indio_dev, 372 struct iio_chan_spec const *chan, 373 int *val, int *val2, long mask) 374 { 375 int ret; 376 struct bmp280_data *data = iio_priv(indio_dev); 377 378 pm_runtime_get_sync(data->dev); 379 mutex_lock(&data->lock); 380 381 switch (mask) { 382 case IIO_CHAN_INFO_PROCESSED: 383 switch (chan->type) { 384 case IIO_HUMIDITYRELATIVE: 385 ret = data->chip_info->read_humid(data, val, val2); 386 break; 387 case IIO_PRESSURE: 388 ret = data->chip_info->read_press(data, val, val2); 389 break; 390 case IIO_TEMP: 391 ret = data->chip_info->read_temp(data, val); 392 break; 393 default: 394 ret = -EINVAL; 395 break; 396 } 397 break; 398 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 399 switch (chan->type) { 400 case IIO_HUMIDITYRELATIVE: 401 *val = 1 << data->oversampling_humid; 402 ret = IIO_VAL_INT; 403 break; 404 case IIO_PRESSURE: 405 *val = 1 << data->oversampling_press; 406 ret = IIO_VAL_INT; 407 break; 408 case IIO_TEMP: 409 *val = 1 << data->oversampling_temp; 410 ret = IIO_VAL_INT; 411 break; 412 default: 413 ret = -EINVAL; 414 break; 415 } 416 break; 417 default: 418 ret = -EINVAL; 419 break; 420 } 421 422 mutex_unlock(&data->lock); 423 pm_runtime_mark_last_busy(data->dev); 424 pm_runtime_put_autosuspend(data->dev); 425 426 return ret; 427 } 428 429 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data, 430 int val) 431 { 432 int i; 433 const int *avail = data->chip_info->oversampling_humid_avail; 434 const int n = data->chip_info->num_oversampling_humid_avail; 435 436 for (i = 0; i < n; i++) { 437 if (avail[i] == val) { 438 data->oversampling_humid = ilog2(val); 439 440 return data->chip_info->chip_config(data); 441 } 442 } 443 return -EINVAL; 444 } 445 446 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data, 447 int val) 448 { 449 int i; 450 const int *avail = data->chip_info->oversampling_temp_avail; 451 const int n = data->chip_info->num_oversampling_temp_avail; 452 453 for (i = 0; i < n; i++) { 454 if (avail[i] == val) { 455 data->oversampling_temp = ilog2(val); 456 457 return data->chip_info->chip_config(data); 458 } 459 } 460 return -EINVAL; 461 } 462 463 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data, 464 int val) 465 { 466 int i; 467 const int *avail = data->chip_info->oversampling_press_avail; 468 const int n = data->chip_info->num_oversampling_press_avail; 469 470 for (i = 0; i < n; i++) { 471 if (avail[i] == val) { 472 data->oversampling_press = ilog2(val); 473 474 return data->chip_info->chip_config(data); 475 } 476 } 477 return -EINVAL; 478 } 479 480 static int bmp280_write_raw(struct iio_dev *indio_dev, 481 struct iio_chan_spec const *chan, 482 int val, int val2, long mask) 483 { 484 int ret = 0; 485 struct bmp280_data *data = iio_priv(indio_dev); 486 487 switch (mask) { 488 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 489 pm_runtime_get_sync(data->dev); 490 mutex_lock(&data->lock); 491 switch (chan->type) { 492 case IIO_HUMIDITYRELATIVE: 493 ret = bmp280_write_oversampling_ratio_humid(data, val); 494 break; 495 case IIO_PRESSURE: 496 ret = bmp280_write_oversampling_ratio_press(data, val); 497 break; 498 case IIO_TEMP: 499 ret = bmp280_write_oversampling_ratio_temp(data, val); 500 break; 501 default: 502 ret = -EINVAL; 503 break; 504 } 505 mutex_unlock(&data->lock); 506 pm_runtime_mark_last_busy(data->dev); 507 pm_runtime_put_autosuspend(data->dev); 508 break; 509 default: 510 return -EINVAL; 511 } 512 513 return ret; 514 } 515 516 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n) 517 { 518 size_t len = 0; 519 int i; 520 521 for (i = 0; i < n; i++) 522 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]); 523 524 buf[len - 1] = '\n'; 525 526 return len; 527 } 528 529 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev, 530 struct device_attribute *attr, char *buf) 531 { 532 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 533 534 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail, 535 data->chip_info->num_oversampling_temp_avail); 536 } 537 538 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev, 539 struct device_attribute *attr, char *buf) 540 { 541 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 542 543 return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail, 544 data->chip_info->num_oversampling_press_avail); 545 } 546 547 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, 548 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0); 549 550 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available, 551 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0); 552 553 static struct attribute *bmp280_attributes[] = { 554 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr, 555 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr, 556 NULL, 557 }; 558 559 static const struct attribute_group bmp280_attrs_group = { 560 .attrs = bmp280_attributes, 561 }; 562 563 static const struct iio_info bmp280_info = { 564 .driver_module = THIS_MODULE, 565 .read_raw = &bmp280_read_raw, 566 .write_raw = &bmp280_write_raw, 567 .attrs = &bmp280_attrs_group, 568 }; 569 570 static int bmp280_chip_config(struct bmp280_data *data) 571 { 572 int ret; 573 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) | 574 BMP280_OSRS_PRESS_X(data->oversampling_press + 1); 575 576 ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS, 577 BMP280_OSRS_TEMP_MASK | 578 BMP280_OSRS_PRESS_MASK | 579 BMP280_MODE_MASK, 580 osrs | BMP280_MODE_NORMAL); 581 if (ret < 0) { 582 dev_err(data->dev, 583 "failed to write ctrl_meas register\n"); 584 return ret; 585 } 586 587 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG, 588 BMP280_FILTER_MASK, 589 BMP280_FILTER_4X); 590 if (ret < 0) { 591 dev_err(data->dev, 592 "failed to write config register\n"); 593 return ret; 594 } 595 596 return ret; 597 } 598 599 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 }; 600 601 static const struct bmp280_chip_info bmp280_chip_info = { 602 .oversampling_temp_avail = bmp280_oversampling_avail, 603 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 604 605 .oversampling_press_avail = bmp280_oversampling_avail, 606 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 607 608 .chip_config = bmp280_chip_config, 609 .read_temp = bmp280_read_temp, 610 .read_press = bmp280_read_press, 611 }; 612 613 static int bme280_chip_config(struct bmp280_data *data) 614 { 615 int ret; 616 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1); 617 618 /* 619 * Oversampling of humidity must be set before oversampling of 620 * temperature/pressure is set to become effective. 621 */ 622 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, 623 BMP280_OSRS_HUMIDITY_MASK, osrs); 624 625 if (ret < 0) 626 return ret; 627 628 return bmp280_chip_config(data); 629 } 630 631 static const struct bmp280_chip_info bme280_chip_info = { 632 .oversampling_temp_avail = bmp280_oversampling_avail, 633 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 634 635 .oversampling_press_avail = bmp280_oversampling_avail, 636 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 637 638 .oversampling_humid_avail = bmp280_oversampling_avail, 639 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail), 640 641 .chip_config = bme280_chip_config, 642 .read_temp = bmp280_read_temp, 643 .read_press = bmp280_read_press, 644 .read_humid = bmp280_read_humid, 645 }; 646 647 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas) 648 { 649 int ret; 650 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 }; 651 unsigned int delay_us; 652 unsigned int ctrl; 653 654 if (data->use_eoc) 655 init_completion(&data->done); 656 657 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas); 658 if (ret) 659 return ret; 660 661 if (data->use_eoc) { 662 /* 663 * If we have a completion interrupt, use it, wait up to 664 * 100ms. The longest conversion time listed is 76.5 ms for 665 * advanced resolution mode. 666 */ 667 ret = wait_for_completion_timeout(&data->done, 668 1 + msecs_to_jiffies(100)); 669 if (!ret) 670 dev_err(data->dev, "timeout waiting for completion\n"); 671 } else { 672 if (ctrl_meas == BMP180_MEAS_TEMP) 673 delay_us = 4500; 674 else 675 delay_us = 676 conversion_time_max[data->oversampling_press]; 677 678 usleep_range(delay_us, delay_us + 1000); 679 } 680 681 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl); 682 if (ret) 683 return ret; 684 685 /* The value of this bit reset to "0" after conversion is complete */ 686 if (ctrl & BMP180_MEAS_SCO) 687 return -EIO; 688 689 return 0; 690 } 691 692 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val) 693 { 694 int ret; 695 __be16 tmp = 0; 696 697 ret = bmp180_measure(data, BMP180_MEAS_TEMP); 698 if (ret) 699 return ret; 700 701 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2); 702 if (ret) 703 return ret; 704 705 *val = be16_to_cpu(tmp); 706 707 return 0; 708 } 709 710 static int bmp180_read_calib(struct bmp280_data *data, 711 struct bmp180_calib *calib) 712 { 713 int ret; 714 int i; 715 __be16 buf[BMP180_REG_CALIB_COUNT / 2]; 716 717 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf, 718 sizeof(buf)); 719 720 if (ret < 0) 721 return ret; 722 723 /* None of the words has the value 0 or 0xFFFF */ 724 for (i = 0; i < ARRAY_SIZE(buf); i++) { 725 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff)) 726 return -EIO; 727 } 728 729 /* Toss the calibration data into the entropy pool */ 730 add_device_randomness(buf, sizeof(buf)); 731 732 calib->AC1 = be16_to_cpu(buf[AC1]); 733 calib->AC2 = be16_to_cpu(buf[AC2]); 734 calib->AC3 = be16_to_cpu(buf[AC3]); 735 calib->AC4 = be16_to_cpu(buf[AC4]); 736 calib->AC5 = be16_to_cpu(buf[AC5]); 737 calib->AC6 = be16_to_cpu(buf[AC6]); 738 calib->B1 = be16_to_cpu(buf[B1]); 739 calib->B2 = be16_to_cpu(buf[B2]); 740 calib->MB = be16_to_cpu(buf[MB]); 741 calib->MC = be16_to_cpu(buf[MC]); 742 calib->MD = be16_to_cpu(buf[MD]); 743 744 return 0; 745 } 746 747 /* 748 * Returns temperature in DegC, resolution is 0.1 DegC. 749 * t_fine carries fine temperature as global value. 750 * 751 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 752 */ 753 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp) 754 { 755 s32 x1, x2; 756 struct bmp180_calib *calib = &data->calib; 757 758 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15; 759 x2 = (calib->MC << 11) / (x1 + calib->MD); 760 data->t_fine = x1 + x2; 761 762 return (data->t_fine + 8) >> 4; 763 } 764 765 static int bmp180_read_temp(struct bmp280_data *data, int *val) 766 { 767 int ret; 768 s32 adc_temp, comp_temp; 769 770 ret = bmp180_read_adc_temp(data, &adc_temp); 771 if (ret) 772 return ret; 773 774 comp_temp = bmp180_compensate_temp(data, adc_temp); 775 776 /* 777 * val might be NULL if we're called by the read_press routine, 778 * who only cares about the carry over t_fine value. 779 */ 780 if (val) { 781 *val = comp_temp * 100; 782 return IIO_VAL_INT; 783 } 784 785 return 0; 786 } 787 788 static int bmp180_read_adc_press(struct bmp280_data *data, int *val) 789 { 790 int ret; 791 __be32 tmp = 0; 792 u8 oss = data->oversampling_press; 793 794 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss)); 795 if (ret) 796 return ret; 797 798 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3); 799 if (ret) 800 return ret; 801 802 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss); 803 804 return 0; 805 } 806 807 /* 808 * Returns pressure in Pa, resolution is 1 Pa. 809 * 810 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 811 */ 812 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press) 813 { 814 s32 x1, x2, x3, p; 815 s32 b3, b6; 816 u32 b4, b7; 817 s32 oss = data->oversampling_press; 818 struct bmp180_calib *calib = &data->calib; 819 820 b6 = data->t_fine - 4000; 821 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11; 822 x2 = calib->AC2 * b6 >> 11; 823 x3 = x1 + x2; 824 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4; 825 x1 = calib->AC3 * b6 >> 13; 826 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16; 827 x3 = (x1 + x2 + 2) >> 2; 828 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15; 829 b7 = ((u32)adc_press - b3) * (50000 >> oss); 830 if (b7 < 0x80000000) 831 p = (b7 * 2) / b4; 832 else 833 p = (b7 / b4) * 2; 834 835 x1 = (p >> 8) * (p >> 8); 836 x1 = (x1 * 3038) >> 16; 837 x2 = (-7357 * p) >> 16; 838 839 return p + ((x1 + x2 + 3791) >> 4); 840 } 841 842 static int bmp180_read_press(struct bmp280_data *data, 843 int *val, int *val2) 844 { 845 int ret; 846 s32 adc_press; 847 u32 comp_press; 848 849 /* Read and compensate temperature so we get a reading of t_fine. */ 850 ret = bmp180_read_temp(data, NULL); 851 if (ret) 852 return ret; 853 854 ret = bmp180_read_adc_press(data, &adc_press); 855 if (ret) 856 return ret; 857 858 comp_press = bmp180_compensate_press(data, adc_press); 859 860 *val = comp_press; 861 *val2 = 1000; 862 863 return IIO_VAL_FRACTIONAL; 864 } 865 866 static int bmp180_chip_config(struct bmp280_data *data) 867 { 868 return 0; 869 } 870 871 static const int bmp180_oversampling_temp_avail[] = { 1 }; 872 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 }; 873 874 static const struct bmp280_chip_info bmp180_chip_info = { 875 .oversampling_temp_avail = bmp180_oversampling_temp_avail, 876 .num_oversampling_temp_avail = 877 ARRAY_SIZE(bmp180_oversampling_temp_avail), 878 879 .oversampling_press_avail = bmp180_oversampling_press_avail, 880 .num_oversampling_press_avail = 881 ARRAY_SIZE(bmp180_oversampling_press_avail), 882 883 .chip_config = bmp180_chip_config, 884 .read_temp = bmp180_read_temp, 885 .read_press = bmp180_read_press, 886 }; 887 888 static irqreturn_t bmp085_eoc_irq(int irq, void *d) 889 { 890 struct bmp280_data *data = d; 891 892 complete(&data->done); 893 894 return IRQ_HANDLED; 895 } 896 897 static int bmp085_fetch_eoc_irq(struct device *dev, 898 const char *name, 899 int irq, 900 struct bmp280_data *data) 901 { 902 unsigned long irq_trig; 903 int ret; 904 905 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); 906 if (irq_trig != IRQF_TRIGGER_RISING) { 907 dev_err(dev, "non-rising trigger given for EOC interrupt, " 908 "trying to enforce it\n"); 909 irq_trig = IRQF_TRIGGER_RISING; 910 } 911 ret = devm_request_threaded_irq(dev, 912 irq, 913 bmp085_eoc_irq, 914 NULL, 915 irq_trig, 916 name, 917 data); 918 if (ret) { 919 /* Bail out without IRQ but keep the driver in place */ 920 dev_err(dev, "unable to request DRDY IRQ\n"); 921 return 0; 922 } 923 924 data->use_eoc = true; 925 return 0; 926 } 927 928 int bmp280_common_probe(struct device *dev, 929 struct regmap *regmap, 930 unsigned int chip, 931 const char *name, 932 int irq) 933 { 934 int ret; 935 struct iio_dev *indio_dev; 936 struct bmp280_data *data; 937 unsigned int chip_id; 938 struct gpio_desc *gpiod; 939 940 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 941 if (!indio_dev) 942 return -ENOMEM; 943 944 data = iio_priv(indio_dev); 945 mutex_init(&data->lock); 946 data->dev = dev; 947 948 indio_dev->dev.parent = dev; 949 indio_dev->name = name; 950 indio_dev->channels = bmp280_channels; 951 indio_dev->info = &bmp280_info; 952 indio_dev->modes = INDIO_DIRECT_MODE; 953 954 switch (chip) { 955 case BMP180_CHIP_ID: 956 indio_dev->num_channels = 2; 957 data->chip_info = &bmp180_chip_info; 958 data->oversampling_press = ilog2(8); 959 data->oversampling_temp = ilog2(1); 960 data->start_up_time = 10000; 961 break; 962 case BMP280_CHIP_ID: 963 indio_dev->num_channels = 2; 964 data->chip_info = &bmp280_chip_info; 965 data->oversampling_press = ilog2(16); 966 data->oversampling_temp = ilog2(2); 967 data->start_up_time = 2000; 968 break; 969 case BME280_CHIP_ID: 970 indio_dev->num_channels = 3; 971 data->chip_info = &bme280_chip_info; 972 data->oversampling_press = ilog2(16); 973 data->oversampling_humid = ilog2(16); 974 data->oversampling_temp = ilog2(2); 975 data->start_up_time = 2000; 976 break; 977 default: 978 return -EINVAL; 979 } 980 981 /* Bring up regulators */ 982 data->vddd = devm_regulator_get(dev, "vddd"); 983 if (IS_ERR(data->vddd)) { 984 dev_err(dev, "failed to get VDDD regulator\n"); 985 return PTR_ERR(data->vddd); 986 } 987 ret = regulator_enable(data->vddd); 988 if (ret) { 989 dev_err(dev, "failed to enable VDDD regulator\n"); 990 return ret; 991 } 992 data->vdda = devm_regulator_get(dev, "vdda"); 993 if (IS_ERR(data->vdda)) { 994 dev_err(dev, "failed to get VDDA regulator\n"); 995 ret = PTR_ERR(data->vdda); 996 goto out_disable_vddd; 997 } 998 ret = regulator_enable(data->vdda); 999 if (ret) { 1000 dev_err(dev, "failed to enable VDDA regulator\n"); 1001 goto out_disable_vddd; 1002 } 1003 /* Wait to make sure we started up properly */ 1004 usleep_range(data->start_up_time, data->start_up_time + 100); 1005 1006 /* Bring chip out of reset if there is an assigned GPIO line */ 1007 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 1008 /* Deassert the signal */ 1009 if (!IS_ERR(gpiod)) { 1010 dev_info(dev, "release reset\n"); 1011 gpiod_set_value(gpiod, 0); 1012 } 1013 1014 data->regmap = regmap; 1015 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id); 1016 if (ret < 0) 1017 goto out_disable_vdda; 1018 if (chip_id != chip) { 1019 dev_err(dev, "bad chip id: expected %x got %x\n", 1020 chip, chip_id); 1021 ret = -EINVAL; 1022 goto out_disable_vdda; 1023 } 1024 1025 ret = data->chip_info->chip_config(data); 1026 if (ret < 0) 1027 goto out_disable_vdda; 1028 1029 dev_set_drvdata(dev, indio_dev); 1030 1031 /* 1032 * The BMP085 and BMP180 has calibration in an E2PROM, read it out 1033 * at probe time. It will not change. 1034 */ 1035 if (chip_id == BMP180_CHIP_ID) { 1036 ret = bmp180_read_calib(data, &data->calib); 1037 if (ret < 0) { 1038 dev_err(data->dev, 1039 "failed to read calibration coefficients\n"); 1040 goto out_disable_vdda; 1041 } 1042 } 1043 1044 /* 1045 * Attempt to grab an optional EOC IRQ - only the BMP085 has this 1046 * however as it happens, the BMP085 shares the chip ID of BMP180 1047 * so we look for an IRQ if we have that. 1048 */ 1049 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) { 1050 ret = bmp085_fetch_eoc_irq(dev, name, irq, data); 1051 if (ret) 1052 goto out_disable_vdda; 1053 } 1054 1055 /* Enable runtime PM */ 1056 pm_runtime_get_noresume(dev); 1057 pm_runtime_set_active(dev); 1058 pm_runtime_enable(dev); 1059 /* 1060 * Set autosuspend to two orders of magnitude larger than the 1061 * start-up time. 1062 */ 1063 pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10); 1064 pm_runtime_use_autosuspend(dev); 1065 pm_runtime_put(dev); 1066 1067 ret = iio_device_register(indio_dev); 1068 if (ret) 1069 goto out_runtime_pm_disable; 1070 1071 1072 return 0; 1073 1074 out_runtime_pm_disable: 1075 pm_runtime_get_sync(data->dev); 1076 pm_runtime_put_noidle(data->dev); 1077 pm_runtime_disable(data->dev); 1078 out_disable_vdda: 1079 regulator_disable(data->vdda); 1080 out_disable_vddd: 1081 regulator_disable(data->vddd); 1082 return ret; 1083 } 1084 EXPORT_SYMBOL(bmp280_common_probe); 1085 1086 int bmp280_common_remove(struct device *dev) 1087 { 1088 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1089 struct bmp280_data *data = iio_priv(indio_dev); 1090 1091 iio_device_unregister(indio_dev); 1092 pm_runtime_get_sync(data->dev); 1093 pm_runtime_put_noidle(data->dev); 1094 pm_runtime_disable(data->dev); 1095 regulator_disable(data->vdda); 1096 regulator_disable(data->vddd); 1097 return 0; 1098 } 1099 EXPORT_SYMBOL(bmp280_common_remove); 1100 1101 #ifdef CONFIG_PM 1102 static int bmp280_runtime_suspend(struct device *dev) 1103 { 1104 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1105 struct bmp280_data *data = iio_priv(indio_dev); 1106 int ret; 1107 1108 ret = regulator_disable(data->vdda); 1109 if (ret) 1110 return ret; 1111 return regulator_disable(data->vddd); 1112 } 1113 1114 static int bmp280_runtime_resume(struct device *dev) 1115 { 1116 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1117 struct bmp280_data *data = iio_priv(indio_dev); 1118 int ret; 1119 1120 ret = regulator_enable(data->vddd); 1121 if (ret) 1122 return ret; 1123 ret = regulator_enable(data->vdda); 1124 if (ret) 1125 return ret; 1126 usleep_range(data->start_up_time, data->start_up_time + 100); 1127 return data->chip_info->chip_config(data); 1128 } 1129 #endif /* CONFIG_PM */ 1130 1131 const struct dev_pm_ops bmp280_dev_pm_ops = { 1132 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1133 pm_runtime_force_resume) 1134 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend, 1135 bmp280_runtime_resume, NULL) 1136 }; 1137 EXPORT_SYMBOL(bmp280_dev_pm_ops); 1138 1139 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>"); 1140 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor"); 1141 MODULE_LICENSE("GPL v2"); 1142