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