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 comp_temp = bmp280_compensate_temp(data, adc_temp); 286 287 /* 288 * val might be NULL if we're called by the read_press routine, 289 * who only cares about the carry over t_fine value. 290 */ 291 if (val) { 292 *val = comp_temp * 10; 293 return IIO_VAL_INT; 294 } 295 296 return 0; 297 } 298 299 static int bmp280_read_press(struct bmp280_data *data, 300 int *val, int *val2) 301 { 302 int ret; 303 __be32 tmp = 0; 304 s32 adc_press; 305 u32 comp_press; 306 307 /* Read and compensate temperature so we get a reading of t_fine. */ 308 ret = bmp280_read_temp(data, NULL); 309 if (ret < 0) 310 return ret; 311 312 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, 313 (u8 *) &tmp, 3); 314 if (ret < 0) { 315 dev_err(data->dev, "failed to read pressure\n"); 316 return ret; 317 } 318 319 adc_press = be32_to_cpu(tmp) >> 12; 320 comp_press = bmp280_compensate_press(data, adc_press); 321 322 *val = comp_press; 323 *val2 = 256000; 324 325 return IIO_VAL_FRACTIONAL; 326 } 327 328 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2) 329 { 330 int ret; 331 __be16 tmp = 0; 332 s32 adc_humidity; 333 u32 comp_humidity; 334 335 /* Read and compensate temperature so we get a reading of t_fine. */ 336 ret = bmp280_read_temp(data, NULL); 337 if (ret < 0) 338 return ret; 339 340 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, 341 (u8 *) &tmp, 2); 342 if (ret < 0) { 343 dev_err(data->dev, "failed to read humidity\n"); 344 return ret; 345 } 346 347 adc_humidity = be16_to_cpu(tmp); 348 comp_humidity = bmp280_compensate_humidity(data, adc_humidity); 349 350 *val = comp_humidity; 351 *val2 = 1024; 352 353 return IIO_VAL_FRACTIONAL; 354 } 355 356 static int bmp280_read_raw(struct iio_dev *indio_dev, 357 struct iio_chan_spec const *chan, 358 int *val, int *val2, long mask) 359 { 360 int ret; 361 struct bmp280_data *data = iio_priv(indio_dev); 362 363 pm_runtime_get_sync(data->dev); 364 mutex_lock(&data->lock); 365 366 switch (mask) { 367 case IIO_CHAN_INFO_PROCESSED: 368 switch (chan->type) { 369 case IIO_HUMIDITYRELATIVE: 370 ret = data->chip_info->read_humid(data, val, val2); 371 break; 372 case IIO_PRESSURE: 373 ret = data->chip_info->read_press(data, val, val2); 374 break; 375 case IIO_TEMP: 376 ret = data->chip_info->read_temp(data, val); 377 break; 378 default: 379 ret = -EINVAL; 380 break; 381 } 382 break; 383 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 384 switch (chan->type) { 385 case IIO_HUMIDITYRELATIVE: 386 *val = 1 << data->oversampling_humid; 387 ret = IIO_VAL_INT; 388 break; 389 case IIO_PRESSURE: 390 *val = 1 << data->oversampling_press; 391 ret = IIO_VAL_INT; 392 break; 393 case IIO_TEMP: 394 *val = 1 << data->oversampling_temp; 395 ret = IIO_VAL_INT; 396 break; 397 default: 398 ret = -EINVAL; 399 break; 400 } 401 break; 402 default: 403 ret = -EINVAL; 404 break; 405 } 406 407 mutex_unlock(&data->lock); 408 pm_runtime_mark_last_busy(data->dev); 409 pm_runtime_put_autosuspend(data->dev); 410 411 return ret; 412 } 413 414 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data, 415 int val) 416 { 417 int i; 418 const int *avail = data->chip_info->oversampling_humid_avail; 419 const int n = data->chip_info->num_oversampling_humid_avail; 420 421 for (i = 0; i < n; i++) { 422 if (avail[i] == val) { 423 data->oversampling_humid = ilog2(val); 424 425 return data->chip_info->chip_config(data); 426 } 427 } 428 return -EINVAL; 429 } 430 431 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data, 432 int val) 433 { 434 int i; 435 const int *avail = data->chip_info->oversampling_temp_avail; 436 const int n = data->chip_info->num_oversampling_temp_avail; 437 438 for (i = 0; i < n; i++) { 439 if (avail[i] == val) { 440 data->oversampling_temp = ilog2(val); 441 442 return data->chip_info->chip_config(data); 443 } 444 } 445 return -EINVAL; 446 } 447 448 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data, 449 int val) 450 { 451 int i; 452 const int *avail = data->chip_info->oversampling_press_avail; 453 const int n = data->chip_info->num_oversampling_press_avail; 454 455 for (i = 0; i < n; i++) { 456 if (avail[i] == val) { 457 data->oversampling_press = ilog2(val); 458 459 return data->chip_info->chip_config(data); 460 } 461 } 462 return -EINVAL; 463 } 464 465 static int bmp280_write_raw(struct iio_dev *indio_dev, 466 struct iio_chan_spec const *chan, 467 int val, int val2, long mask) 468 { 469 int ret = 0; 470 struct bmp280_data *data = iio_priv(indio_dev); 471 472 switch (mask) { 473 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 474 pm_runtime_get_sync(data->dev); 475 mutex_lock(&data->lock); 476 switch (chan->type) { 477 case IIO_HUMIDITYRELATIVE: 478 ret = bmp280_write_oversampling_ratio_humid(data, val); 479 break; 480 case IIO_PRESSURE: 481 ret = bmp280_write_oversampling_ratio_press(data, val); 482 break; 483 case IIO_TEMP: 484 ret = bmp280_write_oversampling_ratio_temp(data, val); 485 break; 486 default: 487 ret = -EINVAL; 488 break; 489 } 490 mutex_unlock(&data->lock); 491 pm_runtime_mark_last_busy(data->dev); 492 pm_runtime_put_autosuspend(data->dev); 493 break; 494 default: 495 return -EINVAL; 496 } 497 498 return ret; 499 } 500 501 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n) 502 { 503 size_t len = 0; 504 int i; 505 506 for (i = 0; i < n; i++) 507 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]); 508 509 buf[len - 1] = '\n'; 510 511 return len; 512 } 513 514 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev, 515 struct device_attribute *attr, char *buf) 516 { 517 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 518 519 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail, 520 data->chip_info->num_oversampling_temp_avail); 521 } 522 523 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev, 524 struct device_attribute *attr, char *buf) 525 { 526 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev)); 527 528 return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail, 529 data->chip_info->num_oversampling_press_avail); 530 } 531 532 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, 533 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0); 534 535 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available, 536 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0); 537 538 static struct attribute *bmp280_attributes[] = { 539 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr, 540 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr, 541 NULL, 542 }; 543 544 static const struct attribute_group bmp280_attrs_group = { 545 .attrs = bmp280_attributes, 546 }; 547 548 static const struct iio_info bmp280_info = { 549 .driver_module = THIS_MODULE, 550 .read_raw = &bmp280_read_raw, 551 .write_raw = &bmp280_write_raw, 552 .attrs = &bmp280_attrs_group, 553 }; 554 555 static int bmp280_chip_config(struct bmp280_data *data) 556 { 557 int ret; 558 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) | 559 BMP280_OSRS_PRESS_X(data->oversampling_press + 1); 560 561 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_MEAS, 562 BMP280_OSRS_TEMP_MASK | 563 BMP280_OSRS_PRESS_MASK | 564 BMP280_MODE_MASK, 565 osrs | BMP280_MODE_NORMAL); 566 if (ret < 0) { 567 dev_err(data->dev, 568 "failed to write ctrl_meas register\n"); 569 return ret; 570 } 571 572 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG, 573 BMP280_FILTER_MASK, 574 BMP280_FILTER_4X); 575 if (ret < 0) { 576 dev_err(data->dev, 577 "failed to write config register\n"); 578 return ret; 579 } 580 581 return ret; 582 } 583 584 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 }; 585 586 static const struct bmp280_chip_info bmp280_chip_info = { 587 .oversampling_temp_avail = bmp280_oversampling_avail, 588 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 589 590 .oversampling_press_avail = bmp280_oversampling_avail, 591 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 592 593 .chip_config = bmp280_chip_config, 594 .read_temp = bmp280_read_temp, 595 .read_press = bmp280_read_press, 596 }; 597 598 static int bme280_chip_config(struct bmp280_data *data) 599 { 600 int ret = bmp280_chip_config(data); 601 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1); 602 603 if (ret < 0) 604 return ret; 605 606 return regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, 607 BMP280_OSRS_HUMIDITY_MASK, osrs); 608 } 609 610 static const struct bmp280_chip_info bme280_chip_info = { 611 .oversampling_temp_avail = bmp280_oversampling_avail, 612 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail), 613 614 .oversampling_press_avail = bmp280_oversampling_avail, 615 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail), 616 617 .oversampling_humid_avail = bmp280_oversampling_avail, 618 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail), 619 620 .chip_config = bme280_chip_config, 621 .read_temp = bmp280_read_temp, 622 .read_press = bmp280_read_press, 623 .read_humid = bmp280_read_humid, 624 }; 625 626 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas) 627 { 628 int ret; 629 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 }; 630 unsigned int delay_us; 631 unsigned int ctrl; 632 633 if (data->use_eoc) 634 init_completion(&data->done); 635 636 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas); 637 if (ret) 638 return ret; 639 640 if (data->use_eoc) { 641 /* 642 * If we have a completion interrupt, use it, wait up to 643 * 100ms. The longest conversion time listed is 76.5 ms for 644 * advanced resolution mode. 645 */ 646 ret = wait_for_completion_timeout(&data->done, 647 1 + msecs_to_jiffies(100)); 648 if (!ret) 649 dev_err(data->dev, "timeout waiting for completion\n"); 650 } else { 651 if (ctrl_meas == BMP180_MEAS_TEMP) 652 delay_us = 4500; 653 else 654 delay_us = 655 conversion_time_max[data->oversampling_press]; 656 657 usleep_range(delay_us, delay_us + 1000); 658 } 659 660 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl); 661 if (ret) 662 return ret; 663 664 /* The value of this bit reset to "0" after conversion is complete */ 665 if (ctrl & BMP180_MEAS_SCO) 666 return -EIO; 667 668 return 0; 669 } 670 671 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val) 672 { 673 int ret; 674 __be16 tmp = 0; 675 676 ret = bmp180_measure(data, BMP180_MEAS_TEMP); 677 if (ret) 678 return ret; 679 680 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2); 681 if (ret) 682 return ret; 683 684 *val = be16_to_cpu(tmp); 685 686 return 0; 687 } 688 689 static int bmp180_read_calib(struct bmp280_data *data, 690 struct bmp180_calib *calib) 691 { 692 int ret; 693 int i; 694 __be16 buf[BMP180_REG_CALIB_COUNT / 2]; 695 696 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf, 697 sizeof(buf)); 698 699 if (ret < 0) 700 return ret; 701 702 /* None of the words has the value 0 or 0xFFFF */ 703 for (i = 0; i < ARRAY_SIZE(buf); i++) { 704 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff)) 705 return -EIO; 706 } 707 708 /* Toss the calibration data into the entropy pool */ 709 add_device_randomness(buf, sizeof(buf)); 710 711 calib->AC1 = be16_to_cpu(buf[AC1]); 712 calib->AC2 = be16_to_cpu(buf[AC2]); 713 calib->AC3 = be16_to_cpu(buf[AC3]); 714 calib->AC4 = be16_to_cpu(buf[AC4]); 715 calib->AC5 = be16_to_cpu(buf[AC5]); 716 calib->AC6 = be16_to_cpu(buf[AC6]); 717 calib->B1 = be16_to_cpu(buf[B1]); 718 calib->B2 = be16_to_cpu(buf[B2]); 719 calib->MB = be16_to_cpu(buf[MB]); 720 calib->MC = be16_to_cpu(buf[MC]); 721 calib->MD = be16_to_cpu(buf[MD]); 722 723 return 0; 724 } 725 726 /* 727 * Returns temperature in DegC, resolution is 0.1 DegC. 728 * t_fine carries fine temperature as global value. 729 * 730 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 731 */ 732 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp) 733 { 734 s32 x1, x2; 735 struct bmp180_calib *calib = &data->calib; 736 737 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15; 738 x2 = (calib->MC << 11) / (x1 + calib->MD); 739 data->t_fine = x1 + x2; 740 741 return (data->t_fine + 8) >> 4; 742 } 743 744 static int bmp180_read_temp(struct bmp280_data *data, int *val) 745 { 746 int ret; 747 s32 adc_temp, comp_temp; 748 749 ret = bmp180_read_adc_temp(data, &adc_temp); 750 if (ret) 751 return ret; 752 753 comp_temp = bmp180_compensate_temp(data, adc_temp); 754 755 /* 756 * val might be NULL if we're called by the read_press routine, 757 * who only cares about the carry over t_fine value. 758 */ 759 if (val) { 760 *val = comp_temp * 100; 761 return IIO_VAL_INT; 762 } 763 764 return 0; 765 } 766 767 static int bmp180_read_adc_press(struct bmp280_data *data, int *val) 768 { 769 int ret; 770 __be32 tmp = 0; 771 u8 oss = data->oversampling_press; 772 773 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss)); 774 if (ret) 775 return ret; 776 777 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3); 778 if (ret) 779 return ret; 780 781 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss); 782 783 return 0; 784 } 785 786 /* 787 * Returns pressure in Pa, resolution is 1 Pa. 788 * 789 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature". 790 */ 791 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press) 792 { 793 s32 x1, x2, x3, p; 794 s32 b3, b6; 795 u32 b4, b7; 796 s32 oss = data->oversampling_press; 797 struct bmp180_calib *calib = &data->calib; 798 799 b6 = data->t_fine - 4000; 800 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11; 801 x2 = calib->AC2 * b6 >> 11; 802 x3 = x1 + x2; 803 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4; 804 x1 = calib->AC3 * b6 >> 13; 805 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16; 806 x3 = (x1 + x2 + 2) >> 2; 807 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15; 808 b7 = ((u32)adc_press - b3) * (50000 >> oss); 809 if (b7 < 0x80000000) 810 p = (b7 * 2) / b4; 811 else 812 p = (b7 / b4) * 2; 813 814 x1 = (p >> 8) * (p >> 8); 815 x1 = (x1 * 3038) >> 16; 816 x2 = (-7357 * p) >> 16; 817 818 return p + ((x1 + x2 + 3791) >> 4); 819 } 820 821 static int bmp180_read_press(struct bmp280_data *data, 822 int *val, int *val2) 823 { 824 int ret; 825 s32 adc_press; 826 u32 comp_press; 827 828 /* Read and compensate temperature so we get a reading of t_fine. */ 829 ret = bmp180_read_temp(data, NULL); 830 if (ret) 831 return ret; 832 833 ret = bmp180_read_adc_press(data, &adc_press); 834 if (ret) 835 return ret; 836 837 comp_press = bmp180_compensate_press(data, adc_press); 838 839 *val = comp_press; 840 *val2 = 1000; 841 842 return IIO_VAL_FRACTIONAL; 843 } 844 845 static int bmp180_chip_config(struct bmp280_data *data) 846 { 847 return 0; 848 } 849 850 static const int bmp180_oversampling_temp_avail[] = { 1 }; 851 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 }; 852 853 static const struct bmp280_chip_info bmp180_chip_info = { 854 .oversampling_temp_avail = bmp180_oversampling_temp_avail, 855 .num_oversampling_temp_avail = 856 ARRAY_SIZE(bmp180_oversampling_temp_avail), 857 858 .oversampling_press_avail = bmp180_oversampling_press_avail, 859 .num_oversampling_press_avail = 860 ARRAY_SIZE(bmp180_oversampling_press_avail), 861 862 .chip_config = bmp180_chip_config, 863 .read_temp = bmp180_read_temp, 864 .read_press = bmp180_read_press, 865 }; 866 867 static irqreturn_t bmp085_eoc_irq(int irq, void *d) 868 { 869 struct bmp280_data *data = d; 870 871 complete(&data->done); 872 873 return IRQ_HANDLED; 874 } 875 876 static int bmp085_fetch_eoc_irq(struct device *dev, 877 const char *name, 878 int irq, 879 struct bmp280_data *data) 880 { 881 unsigned long irq_trig; 882 int ret; 883 884 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); 885 if (irq_trig != IRQF_TRIGGER_RISING) { 886 dev_err(dev, "non-rising trigger given for EOC interrupt, " 887 "trying to enforce it\n"); 888 irq_trig = IRQF_TRIGGER_RISING; 889 } 890 ret = devm_request_threaded_irq(dev, 891 irq, 892 bmp085_eoc_irq, 893 NULL, 894 irq_trig, 895 name, 896 data); 897 if (ret) { 898 /* Bail out without IRQ but keep the driver in place */ 899 dev_err(dev, "unable to request DRDY IRQ\n"); 900 return 0; 901 } 902 903 data->use_eoc = true; 904 return 0; 905 } 906 907 int bmp280_common_probe(struct device *dev, 908 struct regmap *regmap, 909 unsigned int chip, 910 const char *name, 911 int irq) 912 { 913 int ret; 914 struct iio_dev *indio_dev; 915 struct bmp280_data *data; 916 unsigned int chip_id; 917 struct gpio_desc *gpiod; 918 919 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 920 if (!indio_dev) 921 return -ENOMEM; 922 923 data = iio_priv(indio_dev); 924 mutex_init(&data->lock); 925 data->dev = dev; 926 927 indio_dev->dev.parent = dev; 928 indio_dev->name = name; 929 indio_dev->channels = bmp280_channels; 930 indio_dev->info = &bmp280_info; 931 indio_dev->modes = INDIO_DIRECT_MODE; 932 933 switch (chip) { 934 case BMP180_CHIP_ID: 935 indio_dev->num_channels = 2; 936 data->chip_info = &bmp180_chip_info; 937 data->oversampling_press = ilog2(8); 938 data->oversampling_temp = ilog2(1); 939 data->start_up_time = 10000; 940 break; 941 case BMP280_CHIP_ID: 942 indio_dev->num_channels = 2; 943 data->chip_info = &bmp280_chip_info; 944 data->oversampling_press = ilog2(16); 945 data->oversampling_temp = ilog2(2); 946 data->start_up_time = 2000; 947 break; 948 case BME280_CHIP_ID: 949 indio_dev->num_channels = 3; 950 data->chip_info = &bme280_chip_info; 951 data->oversampling_press = ilog2(16); 952 data->oversampling_humid = ilog2(16); 953 data->oversampling_temp = ilog2(2); 954 data->start_up_time = 2000; 955 break; 956 default: 957 return -EINVAL; 958 } 959 960 /* Bring up regulators */ 961 data->vddd = devm_regulator_get(dev, "vddd"); 962 if (IS_ERR(data->vddd)) { 963 dev_err(dev, "failed to get VDDD regulator\n"); 964 return PTR_ERR(data->vddd); 965 } 966 ret = regulator_enable(data->vddd); 967 if (ret) { 968 dev_err(dev, "failed to enable VDDD regulator\n"); 969 return ret; 970 } 971 data->vdda = devm_regulator_get(dev, "vdda"); 972 if (IS_ERR(data->vdda)) { 973 dev_err(dev, "failed to get VDDA regulator\n"); 974 ret = PTR_ERR(data->vdda); 975 goto out_disable_vddd; 976 } 977 ret = regulator_enable(data->vdda); 978 if (ret) { 979 dev_err(dev, "failed to enable VDDA regulator\n"); 980 goto out_disable_vddd; 981 } 982 /* Wait to make sure we started up properly */ 983 usleep_range(data->start_up_time, data->start_up_time + 100); 984 985 /* Bring chip out of reset if there is an assigned GPIO line */ 986 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 987 /* Deassert the signal */ 988 if (!IS_ERR(gpiod)) { 989 dev_info(dev, "release reset\n"); 990 gpiod_set_value(gpiod, 0); 991 } 992 993 data->regmap = regmap; 994 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id); 995 if (ret < 0) 996 goto out_disable_vdda; 997 if (chip_id != chip) { 998 dev_err(dev, "bad chip id: expected %x got %x\n", 999 chip, chip_id); 1000 ret = -EINVAL; 1001 goto out_disable_vdda; 1002 } 1003 1004 ret = data->chip_info->chip_config(data); 1005 if (ret < 0) 1006 goto out_disable_vdda; 1007 1008 dev_set_drvdata(dev, indio_dev); 1009 1010 /* 1011 * The BMP085 and BMP180 has calibration in an E2PROM, read it out 1012 * at probe time. It will not change. 1013 */ 1014 if (chip_id == BMP180_CHIP_ID) { 1015 ret = bmp180_read_calib(data, &data->calib); 1016 if (ret < 0) { 1017 dev_err(data->dev, 1018 "failed to read calibration coefficients\n"); 1019 goto out_disable_vdda; 1020 } 1021 } 1022 1023 /* 1024 * Attempt to grab an optional EOC IRQ - only the BMP085 has this 1025 * however as it happens, the BMP085 shares the chip ID of BMP180 1026 * so we look for an IRQ if we have that. 1027 */ 1028 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) { 1029 ret = bmp085_fetch_eoc_irq(dev, name, irq, data); 1030 if (ret) 1031 goto out_disable_vdda; 1032 } 1033 1034 /* Enable runtime PM */ 1035 pm_runtime_get_noresume(dev); 1036 pm_runtime_set_active(dev); 1037 pm_runtime_enable(dev); 1038 /* 1039 * Set autosuspend to two orders of magnitude larger than the 1040 * start-up time. 1041 */ 1042 pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10); 1043 pm_runtime_use_autosuspend(dev); 1044 pm_runtime_put(dev); 1045 1046 ret = iio_device_register(indio_dev); 1047 if (ret) 1048 goto out_runtime_pm_disable; 1049 1050 1051 return 0; 1052 1053 out_runtime_pm_disable: 1054 pm_runtime_get_sync(data->dev); 1055 pm_runtime_put_noidle(data->dev); 1056 pm_runtime_disable(data->dev); 1057 out_disable_vdda: 1058 regulator_disable(data->vdda); 1059 out_disable_vddd: 1060 regulator_disable(data->vddd); 1061 return ret; 1062 } 1063 EXPORT_SYMBOL(bmp280_common_probe); 1064 1065 int bmp280_common_remove(struct device *dev) 1066 { 1067 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1068 struct bmp280_data *data = iio_priv(indio_dev); 1069 1070 iio_device_unregister(indio_dev); 1071 pm_runtime_get_sync(data->dev); 1072 pm_runtime_put_noidle(data->dev); 1073 pm_runtime_disable(data->dev); 1074 regulator_disable(data->vdda); 1075 regulator_disable(data->vddd); 1076 return 0; 1077 } 1078 EXPORT_SYMBOL(bmp280_common_remove); 1079 1080 #ifdef CONFIG_PM 1081 static int bmp280_runtime_suspend(struct device *dev) 1082 { 1083 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1084 struct bmp280_data *data = iio_priv(indio_dev); 1085 int ret; 1086 1087 ret = regulator_disable(data->vdda); 1088 if (ret) 1089 return ret; 1090 return regulator_disable(data->vddd); 1091 } 1092 1093 static int bmp280_runtime_resume(struct device *dev) 1094 { 1095 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1096 struct bmp280_data *data = iio_priv(indio_dev); 1097 int ret; 1098 1099 ret = regulator_enable(data->vddd); 1100 if (ret) 1101 return ret; 1102 ret = regulator_enable(data->vdda); 1103 if (ret) 1104 return ret; 1105 usleep_range(data->start_up_time, data->start_up_time + 100); 1106 return data->chip_info->chip_config(data); 1107 } 1108 #endif /* CONFIG_PM */ 1109 1110 const struct dev_pm_ops bmp280_dev_pm_ops = { 1111 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1112 pm_runtime_force_resume) 1113 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend, 1114 bmp280_runtime_resume, NULL) 1115 }; 1116 EXPORT_SYMBOL(bmp280_dev_pm_ops); 1117 1118 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>"); 1119 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor"); 1120 MODULE_LICENSE("GPL v2"); 1121