drivers/iio/pressure/bmp280-core.c

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This source file includes following definitions.
bmp280_read_calib
bmp280_compensate_humidity
bmp280_compensate_temp
bmp280_compensate_press
bmp280_read_temp
bmp280_read_press
bmp280_read_humid
bmp280_read_raw
bmp280_write_oversampling_ratio_humid
bmp280_write_oversampling_ratio_temp
bmp280_write_oversampling_ratio_press
bmp280_write_raw
bmp280_show_avail
bmp280_show_temp_oversampling_avail
bmp280_show_press_oversampling_avail
bmp280_chip_config
bme280_chip_config
bmp180_measure
bmp180_read_adc_temp
bmp180_read_calib
bmp180_compensate_temp
bmp180_read_temp
bmp180_read_adc_press
bmp180_compensate_press
bmp180_read_press
bmp180_chip_config
bmp085_eoc_irq
bmp085_fetch_eoc_irq
bmp280_common_probe
bmp280_common_remove
bmp280_runtime_suspend
bmp280_runtime_resume
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>
   4  * Copyright (c) 2012 Bosch Sensortec GmbH
   5  * Copyright (c) 2012 Unixphere AB
   6  * Copyright (c) 2014 Intel Corporation
   7  * Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org>
   8  *
   9  * Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor.
  10  *
  11  * Datasheet:
  12  * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf
  13  * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf
  14  * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
  15  */
  16 
  17 #define pr_fmt(fmt) "bmp280: " fmt
  18 
  19 #include <linux/device.h>
  20 #include <linux/module.h>
  21 #include <linux/regmap.h>
  22 #include <linux/delay.h>
  23 #include <linux/iio/iio.h>
  24 #include <linux/iio/sysfs.h>
  25 #include <linux/gpio/consumer.h>
  26 #include <linux/regulator/consumer.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/irq.h> /* For irq_get_irq_data() */
  29 #include <linux/completion.h>
  30 #include <linux/pm_runtime.h>
  31 #include <linux/random.h>
  32 
  33 #include "bmp280.h"
  34 
  35 /*
  36  * These enums are used for indexing into the array of calibration
  37  * coefficients for BMP180.
  38  */
  39 enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD };
  40 
  41 struct bmp180_calib {
  42         s16 AC1;
  43         s16 AC2;
  44         s16 AC3;
  45         u16 AC4;
  46         u16 AC5;
  47         u16 AC6;
  48         s16 B1;
  49         s16 B2;
  50         s16 MB;
  51         s16 MC;
  52         s16 MD;
  53 };
  54 
  55 /* See datasheet Section 4.2.2. */
  56 struct bmp280_calib {
  57         u16 T1;
  58         s16 T2;
  59         s16 T3;
  60         u16 P1;
  61         s16 P2;
  62         s16 P3;
  63         s16 P4;
  64         s16 P5;
  65         s16 P6;
  66         s16 P7;
  67         s16 P8;
  68         s16 P9;
  69         u8  H1;
  70         s16 H2;
  71         u8  H3;
  72         s16 H4;
  73         s16 H5;
  74         s8  H6;
  75 };
  76 
  77 struct bmp280_data {
  78         struct device *dev;
  79         struct mutex lock;
  80         struct regmap *regmap;
  81         struct completion done;
  82         bool use_eoc;
  83         const struct bmp280_chip_info *chip_info;
  84         union {
  85                 struct bmp180_calib bmp180;
  86                 struct bmp280_calib bmp280;
  87         } calib;
  88         struct regulator *vddd;
  89         struct regulator *vdda;
  90         unsigned int start_up_time; /* in microseconds */
  91 
  92         /* log of base 2 of oversampling rate */
  93         u8 oversampling_press;
  94         u8 oversampling_temp;
  95         u8 oversampling_humid;
  96 
  97         /*
  98          * Carryover value from temperature conversion, used in pressure
  99          * calculation.
 100          */
 101         s32 t_fine;
 102 };
 103 
 104 struct bmp280_chip_info {
 105         const int *oversampling_temp_avail;
 106         int num_oversampling_temp_avail;
 107 
 108         const int *oversampling_press_avail;
 109         int num_oversampling_press_avail;
 110 
 111         const int *oversampling_humid_avail;
 112         int num_oversampling_humid_avail;
 113 
 114         int (*chip_config)(struct bmp280_data *);
 115         int (*read_temp)(struct bmp280_data *, int *);
 116         int (*read_press)(struct bmp280_data *, int *, int *);
 117         int (*read_humid)(struct bmp280_data *, int *, int *);
 118 };
 119 
 120 /*
 121  * These enums are used for indexing into the array of compensation
 122  * parameters for BMP280.
 123  */
 124 enum { T1, T2, T3 };
 125 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 };
 126 
 127 static const struct iio_chan_spec bmp280_channels[] = {
 128         {
 129                 .type = IIO_PRESSURE,
 130                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 131                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
 132         },
 133         {
 134                 .type = IIO_TEMP,
 135                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 136                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
 137         },
 138         {
 139                 .type = IIO_HUMIDITYRELATIVE,
 140                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 141                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
 142         },
 143 };
 144 
 145 static int bmp280_read_calib(struct bmp280_data *data,
 146                              struct bmp280_calib *calib,
 147                              unsigned int chip)
 148 {
 149         int ret;
 150         unsigned int tmp;
 151         struct device *dev = data->dev;
 152         __le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
 153         __le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
 154 
 155         /* Read temperature calibration values. */
 156         ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
 157                                t_buf, BMP280_COMP_TEMP_REG_COUNT);
 158         if (ret < 0) {
 159                 dev_err(data->dev,
 160                         "failed to read temperature calibration parameters\n");
 161                 return ret;
 162         }
 163 
 164         /* Toss the temperature calibration data into the entropy pool */
 165         add_device_randomness(t_buf, sizeof(t_buf));
 166 
 167         calib->T1 = le16_to_cpu(t_buf[T1]);
 168         calib->T2 = le16_to_cpu(t_buf[T2]);
 169         calib->T3 = le16_to_cpu(t_buf[T3]);
 170 
 171         /* Read pressure calibration values. */
 172         ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
 173                                p_buf, BMP280_COMP_PRESS_REG_COUNT);
 174         if (ret < 0) {
 175                 dev_err(data->dev,
 176                         "failed to read pressure calibration parameters\n");
 177                 return ret;
 178         }
 179 
 180         /* Toss the pressure calibration data into the entropy pool */
 181         add_device_randomness(p_buf, sizeof(p_buf));
 182 
 183         calib->P1 = le16_to_cpu(p_buf[P1]);
 184         calib->P2 = le16_to_cpu(p_buf[P2]);
 185         calib->P3 = le16_to_cpu(p_buf[P3]);
 186         calib->P4 = le16_to_cpu(p_buf[P4]);
 187         calib->P5 = le16_to_cpu(p_buf[P5]);
 188         calib->P6 = le16_to_cpu(p_buf[P6]);
 189         calib->P7 = le16_to_cpu(p_buf[P7]);
 190         calib->P8 = le16_to_cpu(p_buf[P8]);
 191         calib->P9 = le16_to_cpu(p_buf[P9]);
 192 
 193         /*
 194          * Read humidity calibration values.
 195          * Due to some odd register addressing we cannot just
 196          * do a big bulk read. Instead, we have to read each Hx
 197          * value separately and sometimes do some bit shifting...
 198          * Humidity data is only available on BME280.
 199          */
 200         if (chip != BME280_CHIP_ID)
 201                 return 0;
 202 
 203         ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp);
 204         if (ret < 0) {
 205                 dev_err(dev, "failed to read H1 comp value\n");
 206                 return ret;
 207         }
 208         calib->H1 = tmp;
 209 
 210         ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2);
 211         if (ret < 0) {
 212                 dev_err(dev, "failed to read H2 comp value\n");
 213                 return ret;
 214         }
 215         calib->H2 = sign_extend32(le16_to_cpu(tmp), 15);
 216 
 217         ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp);
 218         if (ret < 0) {
 219                 dev_err(dev, "failed to read H3 comp value\n");
 220                 return ret;
 221         }
 222         calib->H3 = tmp;
 223 
 224         ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2);
 225         if (ret < 0) {
 226                 dev_err(dev, "failed to read H4 comp value\n");
 227                 return ret;
 228         }
 229         calib->H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) |
 230                                   (be16_to_cpu(tmp) & 0xf), 11);
 231 
 232         ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2);
 233         if (ret < 0) {
 234                 dev_err(dev, "failed to read H5 comp value\n");
 235                 return ret;
 236         }
 237         calib->H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11);
 238 
 239         ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
 240         if (ret < 0) {
 241                 dev_err(dev, "failed to read H6 comp value\n");
 242                 return ret;
 243         }
 244         calib->H6 = sign_extend32(tmp, 7);
 245 
 246         return 0;
 247 }
 248 /*
 249  * Returns humidity in percent, resolution is 0.01 percent. Output value of
 250  * "47445" represents 47445/1024 = 46.333 %RH.
 251  *
 252  * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
 253  */
 254 static u32 bmp280_compensate_humidity(struct bmp280_data *data,
 255                                       s32 adc_humidity)
 256 {
 257         s32 var;
 258         struct bmp280_calib *calib = &data->calib.bmp280;
 259 
 260         var = ((s32)data->t_fine) - (s32)76800;
 261         var = ((((adc_humidity << 14) - (calib->H4 << 20) - (calib->H5 * var))
 262                 + (s32)16384) >> 15) * (((((((var * calib->H6) >> 10)
 263                 * (((var * (s32)calib->H3) >> 11) + (s32)32768)) >> 10)
 264                 + (s32)2097152) * calib->H2 + 8192) >> 14);
 265         var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4;
 266 
 267         return var >> 12;
 268 };
 269 
 270 /*
 271  * Returns temperature in DegC, resolution is 0.01 DegC.  Output value of
 272  * "5123" equals 51.23 DegC.  t_fine carries fine temperature as global
 273  * value.
 274  *
 275  * Taken from datasheet, Section 3.11.3, "Compensation formula".
 276  */
 277 static s32 bmp280_compensate_temp(struct bmp280_data *data,
 278                                   s32 adc_temp)
 279 {
 280         s32 var1, var2;
 281         struct bmp280_calib *calib = &data->calib.bmp280;
 282 
 283         var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) *
 284                 ((s32)calib->T2)) >> 11;
 285         var2 = (((((adc_temp >> 4) - ((s32)calib->T1)) *
 286                   ((adc_temp >> 4) - ((s32)calib->T1))) >> 12) *
 287                 ((s32)calib->T3)) >> 14;
 288         data->t_fine = var1 + var2;
 289 
 290         return (data->t_fine * 5 + 128) >> 8;
 291 }
 292 
 293 /*
 294  * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24
 295  * integer bits and 8 fractional bits).  Output value of "24674867"
 296  * represents 24674867/256 = 96386.2 Pa = 963.862 hPa
 297  *
 298  * Taken from datasheet, Section 3.11.3, "Compensation formula".
 299  */
 300 static u32 bmp280_compensate_press(struct bmp280_data *data,
 301                                    s32 adc_press)
 302 {
 303         s64 var1, var2, p;
 304         struct bmp280_calib *calib = &data->calib.bmp280;
 305 
 306         var1 = ((s64)data->t_fine) - 128000;
 307         var2 = var1 * var1 * (s64)calib->P6;
 308         var2 += (var1 * (s64)calib->P5) << 17;
 309         var2 += ((s64)calib->P4) << 35;
 310         var1 = ((var1 * var1 * (s64)calib->P3) >> 8) +
 311                 ((var1 * (s64)calib->P2) << 12);
 312         var1 = ((((s64)1) << 47) + var1) * ((s64)calib->P1) >> 33;
 313 
 314         if (var1 == 0)
 315                 return 0;
 316 
 317         p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
 318         p = div64_s64(p, var1);
 319         var1 = (((s64)calib->P9) * (p >> 13) * (p >> 13)) >> 25;
 320         var2 = ((s64)(calib->P8) * p) >> 19;
 321         p = ((p + var1 + var2) >> 8) + (((s64)calib->P7) << 4);
 322 
 323         return (u32)p;
 324 }
 325 
 326 static int bmp280_read_temp(struct bmp280_data *data,
 327                             int *val)
 328 {
 329         int ret;
 330         __be32 tmp = 0;
 331         s32 adc_temp, comp_temp;
 332 
 333         ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
 334                                (u8 *) &tmp, 3);
 335         if (ret < 0) {
 336                 dev_err(data->dev, "failed to read temperature\n");
 337                 return ret;
 338         }
 339 
 340         adc_temp = be32_to_cpu(tmp) >> 12;
 341         if (adc_temp == BMP280_TEMP_SKIPPED) {
 342                 /* reading was skipped */
 343                 dev_err(data->dev, "reading temperature skipped\n");
 344                 return -EIO;
 345         }
 346         comp_temp = bmp280_compensate_temp(data, adc_temp);
 347 
 348         /*
 349          * val might be NULL if we're called by the read_press routine,
 350          * who only cares about the carry over t_fine value.
 351          */
 352         if (val) {
 353                 *val = comp_temp * 10;
 354                 return IIO_VAL_INT;
 355         }
 356 
 357         return 0;
 358 }
 359 
 360 static int bmp280_read_press(struct bmp280_data *data,
 361                              int *val, int *val2)
 362 {
 363         int ret;
 364         __be32 tmp = 0;
 365         s32 adc_press;
 366         u32 comp_press;
 367 
 368         /* Read and compensate temperature so we get a reading of t_fine. */
 369         ret = bmp280_read_temp(data, NULL);
 370         if (ret < 0)
 371                 return ret;
 372 
 373         ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
 374                                (u8 *) &tmp, 3);
 375         if (ret < 0) {
 376                 dev_err(data->dev, "failed to read pressure\n");
 377                 return ret;
 378         }
 379 
 380         adc_press = be32_to_cpu(tmp) >> 12;
 381         if (adc_press == BMP280_PRESS_SKIPPED) {
 382                 /* reading was skipped */
 383                 dev_err(data->dev, "reading pressure skipped\n");
 384                 return -EIO;
 385         }
 386         comp_press = bmp280_compensate_press(data, adc_press);
 387 
 388         *val = comp_press;
 389         *val2 = 256000;
 390 
 391         return IIO_VAL_FRACTIONAL;
 392 }
 393 
 394 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 395 {
 396         int ret;
 397         __be16 tmp = 0;
 398         s32 adc_humidity;
 399         u32 comp_humidity;
 400 
 401         /* Read and compensate temperature so we get a reading of t_fine. */
 402         ret = bmp280_read_temp(data, NULL);
 403         if (ret < 0)
 404                 return ret;
 405 
 406         ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
 407                                (u8 *) &tmp, 2);
 408         if (ret < 0) {
 409                 dev_err(data->dev, "failed to read humidity\n");
 410                 return ret;
 411         }
 412 
 413         adc_humidity = be16_to_cpu(tmp);
 414         if (adc_humidity == BMP280_HUMIDITY_SKIPPED) {
 415                 /* reading was skipped */
 416                 dev_err(data->dev, "reading humidity skipped\n");
 417                 return -EIO;
 418         }
 419         comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
 420 
 421         *val = comp_humidity * 1000 / 1024;
 422 
 423         return IIO_VAL_INT;
 424 }
 425 
 426 static int bmp280_read_raw(struct iio_dev *indio_dev,
 427                            struct iio_chan_spec const *chan,
 428                            int *val, int *val2, long mask)
 429 {
 430         int ret;
 431         struct bmp280_data *data = iio_priv(indio_dev);
 432 
 433         pm_runtime_get_sync(data->dev);
 434         mutex_lock(&data->lock);
 435 
 436         switch (mask) {
 437         case IIO_CHAN_INFO_PROCESSED:
 438                 switch (chan->type) {
 439                 case IIO_HUMIDITYRELATIVE:
 440                         ret = data->chip_info->read_humid(data, val, val2);
 441                         break;
 442                 case IIO_PRESSURE:
 443                         ret = data->chip_info->read_press(data, val, val2);
 444                         break;
 445                 case IIO_TEMP:
 446                         ret = data->chip_info->read_temp(data, val);
 447                         break;
 448                 default:
 449                         ret = -EINVAL;
 450                         break;
 451                 }
 452                 break;
 453         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 454                 switch (chan->type) {
 455                 case IIO_HUMIDITYRELATIVE:
 456                         *val = 1 << data->oversampling_humid;
 457                         ret = IIO_VAL_INT;
 458                         break;
 459                 case IIO_PRESSURE:
 460                         *val = 1 << data->oversampling_press;
 461                         ret = IIO_VAL_INT;
 462                         break;
 463                 case IIO_TEMP:
 464                         *val = 1 << data->oversampling_temp;
 465                         ret = IIO_VAL_INT;
 466                         break;
 467                 default:
 468                         ret = -EINVAL;
 469                         break;
 470                 }
 471                 break;
 472         default:
 473                 ret = -EINVAL;
 474                 break;
 475         }
 476 
 477         mutex_unlock(&data->lock);
 478         pm_runtime_mark_last_busy(data->dev);
 479         pm_runtime_put_autosuspend(data->dev);
 480 
 481         return ret;
 482 }
 483 
 484 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
 485                                                int val)
 486 {
 487         int i;
 488         const int *avail = data->chip_info->oversampling_humid_avail;
 489         const int n = data->chip_info->num_oversampling_humid_avail;
 490 
 491         for (i = 0; i < n; i++) {
 492                 if (avail[i] == val) {
 493                         data->oversampling_humid = ilog2(val);
 494 
 495                         return data->chip_info->chip_config(data);
 496                 }
 497         }
 498         return -EINVAL;
 499 }
 500 
 501 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
 502                                                int val)
 503 {
 504         int i;
 505         const int *avail = data->chip_info->oversampling_temp_avail;
 506         const int n = data->chip_info->num_oversampling_temp_avail;
 507 
 508         for (i = 0; i < n; i++) {
 509                 if (avail[i] == val) {
 510                         data->oversampling_temp = ilog2(val);
 511 
 512                         return data->chip_info->chip_config(data);
 513                 }
 514         }
 515         return -EINVAL;
 516 }
 517 
 518 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
 519                                                int val)
 520 {
 521         int i;
 522         const int *avail = data->chip_info->oversampling_press_avail;
 523         const int n = data->chip_info->num_oversampling_press_avail;
 524 
 525         for (i = 0; i < n; i++) {
 526                 if (avail[i] == val) {
 527                         data->oversampling_press = ilog2(val);
 528 
 529                         return data->chip_info->chip_config(data);
 530                 }
 531         }
 532         return -EINVAL;
 533 }
 534 
 535 static int bmp280_write_raw(struct iio_dev *indio_dev,
 536                             struct iio_chan_spec const *chan,
 537                             int val, int val2, long mask)
 538 {
 539         int ret = 0;
 540         struct bmp280_data *data = iio_priv(indio_dev);
 541 
 542         switch (mask) {
 543         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 544                 pm_runtime_get_sync(data->dev);
 545                 mutex_lock(&data->lock);
 546                 switch (chan->type) {
 547                 case IIO_HUMIDITYRELATIVE:
 548                         ret = bmp280_write_oversampling_ratio_humid(data, val);
 549                         break;
 550                 case IIO_PRESSURE:
 551                         ret = bmp280_write_oversampling_ratio_press(data, val);
 552                         break;
 553                 case IIO_TEMP:
 554                         ret = bmp280_write_oversampling_ratio_temp(data, val);
 555                         break;
 556                 default:
 557                         ret = -EINVAL;
 558                         break;
 559                 }
 560                 mutex_unlock(&data->lock);
 561                 pm_runtime_mark_last_busy(data->dev);
 562                 pm_runtime_put_autosuspend(data->dev);
 563                 break;
 564         default:
 565                 return -EINVAL;
 566         }
 567 
 568         return ret;
 569 }
 570 
 571 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n)
 572 {
 573         size_t len = 0;
 574         int i;
 575 
 576         for (i = 0; i < n; i++)
 577                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]);
 578 
 579         buf[len - 1] = '\n';
 580 
 581         return len;
 582 }
 583 
 584 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev,
 585                                 struct device_attribute *attr, char *buf)
 586 {
 587         struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
 588 
 589         return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail,
 590                                  data->chip_info->num_oversampling_temp_avail);
 591 }
 592 
 593 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev,
 594                                 struct device_attribute *attr, char *buf)
 595 {
 596         struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
 597 
 598         return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail,
 599                                  data->chip_info->num_oversampling_press_avail);
 600 }
 601 
 602 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available,
 603         S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0);
 604 
 605 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available,
 606         S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0);
 607 
 608 static struct attribute *bmp280_attributes[] = {
 609         &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
 610         &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr,
 611         NULL,
 612 };
 613 
 614 static const struct attribute_group bmp280_attrs_group = {
 615         .attrs = bmp280_attributes,
 616 };
 617 
 618 static const struct iio_info bmp280_info = {
 619         .read_raw = &bmp280_read_raw,
 620         .write_raw = &bmp280_write_raw,
 621         .attrs = &bmp280_attrs_group,
 622 };
 623 
 624 static int bmp280_chip_config(struct bmp280_data *data)
 625 {
 626         int ret;
 627         u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
 628                   BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
 629 
 630         ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
 631                                  BMP280_OSRS_TEMP_MASK |
 632                                  BMP280_OSRS_PRESS_MASK |
 633                                  BMP280_MODE_MASK,
 634                                  osrs | BMP280_MODE_NORMAL);
 635         if (ret < 0) {
 636                 dev_err(data->dev,
 637                         "failed to write ctrl_meas register\n");
 638                 return ret;
 639         }
 640 
 641         ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG,
 642                                  BMP280_FILTER_MASK,
 643                                  BMP280_FILTER_4X);
 644         if (ret < 0) {
 645                 dev_err(data->dev,
 646                         "failed to write config register\n");
 647                 return ret;
 648         }
 649 
 650         return ret;
 651 }
 652 
 653 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 };
 654 
 655 static const struct bmp280_chip_info bmp280_chip_info = {
 656         .oversampling_temp_avail = bmp280_oversampling_avail,
 657         .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 658 
 659         .oversampling_press_avail = bmp280_oversampling_avail,
 660         .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 661 
 662         .chip_config = bmp280_chip_config,
 663         .read_temp = bmp280_read_temp,
 664         .read_press = bmp280_read_press,
 665 };
 666 
 667 static int bme280_chip_config(struct bmp280_data *data)
 668 {
 669         int ret;
 670         u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
 671 
 672         /*
 673          * Oversampling of humidity must be set before oversampling of
 674          * temperature/pressure is set to become effective.
 675          */
 676         ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
 677                                   BMP280_OSRS_HUMIDITY_MASK, osrs);
 678 
 679         if (ret < 0)
 680                 return ret;
 681 
 682         return bmp280_chip_config(data);
 683 }
 684 
 685 static const struct bmp280_chip_info bme280_chip_info = {
 686         .oversampling_temp_avail = bmp280_oversampling_avail,
 687         .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 688 
 689         .oversampling_press_avail = bmp280_oversampling_avail,
 690         .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 691 
 692         .oversampling_humid_avail = bmp280_oversampling_avail,
 693         .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 694 
 695         .chip_config = bme280_chip_config,
 696         .read_temp = bmp280_read_temp,
 697         .read_press = bmp280_read_press,
 698         .read_humid = bmp280_read_humid,
 699 };
 700 
 701 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
 702 {
 703         int ret;
 704         const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
 705         unsigned int delay_us;
 706         unsigned int ctrl;
 707 
 708         if (data->use_eoc)
 709                 init_completion(&data->done);
 710 
 711         ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas);
 712         if (ret)
 713                 return ret;
 714 
 715         if (data->use_eoc) {
 716                 /*
 717                  * If we have a completion interrupt, use it, wait up to
 718                  * 100ms. The longest conversion time listed is 76.5 ms for
 719                  * advanced resolution mode.
 720                  */
 721                 ret = wait_for_completion_timeout(&data->done,
 722                                                   1 + msecs_to_jiffies(100));
 723                 if (!ret)
 724                         dev_err(data->dev, "timeout waiting for completion\n");
 725         } else {
 726                 if (ctrl_meas == BMP180_MEAS_TEMP)
 727                         delay_us = 4500;
 728                 else
 729                         delay_us =
 730                                 conversion_time_max[data->oversampling_press];
 731 
 732                 usleep_range(delay_us, delay_us + 1000);
 733         }
 734 
 735         ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl);
 736         if (ret)
 737                 return ret;
 738 
 739         /* The value of this bit reset to "0" after conversion is complete */
 740         if (ctrl & BMP180_MEAS_SCO)
 741                 return -EIO;
 742 
 743         return 0;
 744 }
 745 
 746 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 747 {
 748         int ret;
 749         __be16 tmp = 0;
 750 
 751         ret = bmp180_measure(data, BMP180_MEAS_TEMP);
 752         if (ret)
 753                 return ret;
 754 
 755         ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2);
 756         if (ret)
 757                 return ret;
 758 
 759         *val = be16_to_cpu(tmp);
 760 
 761         return 0;
 762 }
 763 
 764 static int bmp180_read_calib(struct bmp280_data *data,
 765                              struct bmp180_calib *calib)
 766 {
 767         int ret;
 768         int i;
 769         __be16 buf[BMP180_REG_CALIB_COUNT / 2];
 770 
 771         ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
 772                                sizeof(buf));
 773 
 774         if (ret < 0)
 775                 return ret;
 776 
 777         /* None of the words has the value 0 or 0xFFFF */
 778         for (i = 0; i < ARRAY_SIZE(buf); i++) {
 779                 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff))
 780                         return -EIO;
 781         }
 782 
 783         /* Toss the calibration data into the entropy pool */
 784         add_device_randomness(buf, sizeof(buf));
 785 
 786         calib->AC1 = be16_to_cpu(buf[AC1]);
 787         calib->AC2 = be16_to_cpu(buf[AC2]);
 788         calib->AC3 = be16_to_cpu(buf[AC3]);
 789         calib->AC4 = be16_to_cpu(buf[AC4]);
 790         calib->AC5 = be16_to_cpu(buf[AC5]);
 791         calib->AC6 = be16_to_cpu(buf[AC6]);
 792         calib->B1 = be16_to_cpu(buf[B1]);
 793         calib->B2 = be16_to_cpu(buf[B2]);
 794         calib->MB = be16_to_cpu(buf[MB]);
 795         calib->MC = be16_to_cpu(buf[MC]);
 796         calib->MD = be16_to_cpu(buf[MD]);
 797 
 798         return 0;
 799 }
 800 
 801 /*
 802  * Returns temperature in DegC, resolution is 0.1 DegC.
 803  * t_fine carries fine temperature as global value.
 804  *
 805  * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
 806  */
 807 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
 808 {
 809         s32 x1, x2;
 810         struct bmp180_calib *calib = &data->calib.bmp180;
 811 
 812         x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15;
 813         x2 = (calib->MC << 11) / (x1 + calib->MD);
 814         data->t_fine = x1 + x2;
 815 
 816         return (data->t_fine + 8) >> 4;
 817 }
 818 
 819 static int bmp180_read_temp(struct bmp280_data *data, int *val)
 820 {
 821         int ret;
 822         s32 adc_temp, comp_temp;
 823 
 824         ret = bmp180_read_adc_temp(data, &adc_temp);
 825         if (ret)
 826                 return ret;
 827 
 828         comp_temp = bmp180_compensate_temp(data, adc_temp);
 829 
 830         /*
 831          * val might be NULL if we're called by the read_press routine,
 832          * who only cares about the carry over t_fine value.
 833          */
 834         if (val) {
 835                 *val = comp_temp * 100;
 836                 return IIO_VAL_INT;
 837         }
 838 
 839         return 0;
 840 }
 841 
 842 static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
 843 {
 844         int ret;
 845         __be32 tmp = 0;
 846         u8 oss = data->oversampling_press;
 847 
 848         ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
 849         if (ret)
 850                 return ret;
 851 
 852         ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3);
 853         if (ret)
 854                 return ret;
 855 
 856         *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
 857 
 858         return 0;
 859 }
 860 
 861 /*
 862  * Returns pressure in Pa, resolution is 1 Pa.
 863  *
 864  * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
 865  */
 866 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
 867 {
 868         s32 x1, x2, x3, p;
 869         s32 b3, b6;
 870         u32 b4, b7;
 871         s32 oss = data->oversampling_press;
 872         struct bmp180_calib *calib = &data->calib.bmp180;
 873 
 874         b6 = data->t_fine - 4000;
 875         x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
 876         x2 = calib->AC2 * b6 >> 11;
 877         x3 = x1 + x2;
 878         b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4;
 879         x1 = calib->AC3 * b6 >> 13;
 880         x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16;
 881         x3 = (x1 + x2 + 2) >> 2;
 882         b4 = calib->AC4 * (u32)(x3 + 32768) >> 15;
 883         b7 = ((u32)adc_press - b3) * (50000 >> oss);
 884         if (b7 < 0x80000000)
 885                 p = (b7 * 2) / b4;
 886         else
 887                 p = (b7 / b4) * 2;
 888 
 889         x1 = (p >> 8) * (p >> 8);
 890         x1 = (x1 * 3038) >> 16;
 891         x2 = (-7357 * p) >> 16;
 892 
 893         return p + ((x1 + x2 + 3791) >> 4);
 894 }
 895 
 896 static int bmp180_read_press(struct bmp280_data *data,
 897                              int *val, int *val2)
 898 {
 899         int ret;
 900         s32 adc_press;
 901         u32 comp_press;
 902 
 903         /* Read and compensate temperature so we get a reading of t_fine. */
 904         ret = bmp180_read_temp(data, NULL);
 905         if (ret)
 906                 return ret;
 907 
 908         ret = bmp180_read_adc_press(data, &adc_press);
 909         if (ret)
 910                 return ret;
 911 
 912         comp_press = bmp180_compensate_press(data, adc_press);
 913 
 914         *val = comp_press;
 915         *val2 = 1000;
 916 
 917         return IIO_VAL_FRACTIONAL;
 918 }
 919 
 920 static int bmp180_chip_config(struct bmp280_data *data)
 921 {
 922         return 0;
 923 }
 924 
 925 static const int bmp180_oversampling_temp_avail[] = { 1 };
 926 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 };
 927 
 928 static const struct bmp280_chip_info bmp180_chip_info = {
 929         .oversampling_temp_avail = bmp180_oversampling_temp_avail,
 930         .num_oversampling_temp_avail =
 931                 ARRAY_SIZE(bmp180_oversampling_temp_avail),
 932 
 933         .oversampling_press_avail = bmp180_oversampling_press_avail,
 934         .num_oversampling_press_avail =
 935                 ARRAY_SIZE(bmp180_oversampling_press_avail),
 936 
 937         .chip_config = bmp180_chip_config,
 938         .read_temp = bmp180_read_temp,
 939         .read_press = bmp180_read_press,
 940 };
 941 
 942 static irqreturn_t bmp085_eoc_irq(int irq, void *d)
 943 {
 944         struct bmp280_data *data = d;
 945 
 946         complete(&data->done);
 947 
 948         return IRQ_HANDLED;
 949 }
 950 
 951 static int bmp085_fetch_eoc_irq(struct device *dev,
 952                                 const char *name,
 953                                 int irq,
 954                                 struct bmp280_data *data)
 955 {
 956         unsigned long irq_trig;
 957         int ret;
 958 
 959         irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
 960         if (irq_trig != IRQF_TRIGGER_RISING) {
 961                 dev_err(dev, "non-rising trigger given for EOC interrupt, "
 962                         "trying to enforce it\n");
 963                 irq_trig = IRQF_TRIGGER_RISING;
 964         }
 965         ret = devm_request_threaded_irq(dev,
 966                         irq,
 967                         bmp085_eoc_irq,
 968                         NULL,
 969                         irq_trig,
 970                         name,
 971                         data);
 972         if (ret) {
 973                 /* Bail out without IRQ but keep the driver in place */
 974                 dev_err(dev, "unable to request DRDY IRQ\n");
 975                 return 0;
 976         }
 977 
 978         data->use_eoc = true;
 979         return 0;
 980 }
 981 
 982 int bmp280_common_probe(struct device *dev,
 983                         struct regmap *regmap,
 984                         unsigned int chip,
 985                         const char *name,
 986                         int irq)
 987 {
 988         int ret;
 989         struct iio_dev *indio_dev;
 990         struct bmp280_data *data;
 991         unsigned int chip_id;
 992         struct gpio_desc *gpiod;
 993 
 994         indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 995         if (!indio_dev)
 996                 return -ENOMEM;
 997 
 998         data = iio_priv(indio_dev);
 999         mutex_init(&data->lock);
1000         data->dev = dev;
1001 
1002         indio_dev->dev.parent = dev;
1003         indio_dev->name = name;
1004         indio_dev->channels = bmp280_channels;
1005         indio_dev->info = &bmp280_info;
1006         indio_dev->modes = INDIO_DIRECT_MODE;
1007 
1008         switch (chip) {
1009         case BMP180_CHIP_ID:
1010                 indio_dev->num_channels = 2;
1011                 data->chip_info = &bmp180_chip_info;
1012                 data->oversampling_press = ilog2(8);
1013                 data->oversampling_temp = ilog2(1);
1014                 data->start_up_time = 10000;
1015                 break;
1016         case BMP280_CHIP_ID:
1017                 indio_dev->num_channels = 2;
1018                 data->chip_info = &bmp280_chip_info;
1019                 data->oversampling_press = ilog2(16);
1020                 data->oversampling_temp = ilog2(2);
1021                 data->start_up_time = 2000;
1022                 break;
1023         case BME280_CHIP_ID:
1024                 indio_dev->num_channels = 3;
1025                 data->chip_info = &bme280_chip_info;
1026                 data->oversampling_press = ilog2(16);
1027                 data->oversampling_humid = ilog2(16);
1028                 data->oversampling_temp = ilog2(2);
1029                 data->start_up_time = 2000;
1030                 break;
1031         default:
1032                 return -EINVAL;
1033         }
1034 
1035         /* Bring up regulators */
1036         data->vddd = devm_regulator_get(dev, "vddd");
1037         if (IS_ERR(data->vddd)) {
1038                 dev_err(dev, "failed to get VDDD regulator\n");
1039                 return PTR_ERR(data->vddd);
1040         }
1041         ret = regulator_enable(data->vddd);
1042         if (ret) {
1043                 dev_err(dev, "failed to enable VDDD regulator\n");
1044                 return ret;
1045         }
1046         data->vdda = devm_regulator_get(dev, "vdda");
1047         if (IS_ERR(data->vdda)) {
1048                 dev_err(dev, "failed to get VDDA regulator\n");
1049                 ret = PTR_ERR(data->vdda);
1050                 goto out_disable_vddd;
1051         }
1052         ret = regulator_enable(data->vdda);
1053         if (ret) {
1054                 dev_err(dev, "failed to enable VDDA regulator\n");
1055                 goto out_disable_vddd;
1056         }
1057         /* Wait to make sure we started up properly */
1058         usleep_range(data->start_up_time, data->start_up_time + 100);
1059 
1060         /* Bring chip out of reset if there is an assigned GPIO line */
1061         gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
1062         /* Deassert the signal */
1063         if (!IS_ERR(gpiod)) {
1064                 dev_info(dev, "release reset\n");
1065                 gpiod_set_value(gpiod, 0);
1066         }
1067 
1068         data->regmap = regmap;
1069         ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
1070         if (ret < 0)
1071                 goto out_disable_vdda;
1072         if (chip_id != chip) {
1073                 dev_err(dev, "bad chip id: expected %x got %x\n",
1074                         chip, chip_id);
1075                 ret = -EINVAL;
1076                 goto out_disable_vdda;
1077         }
1078 
1079         ret = data->chip_info->chip_config(data);
1080         if (ret < 0)
1081                 goto out_disable_vdda;
1082 
1083         dev_set_drvdata(dev, indio_dev);
1084 
1085         /*
1086          * Some chips have calibration parameters "programmed into the devices'
1087          * non-volatile memory during production". Let's read them out at probe
1088          * time once. They will not change.
1089          */
1090         if (chip_id  == BMP180_CHIP_ID) {
1091                 ret = bmp180_read_calib(data, &data->calib.bmp180);
1092                 if (ret < 0) {
1093                         dev_err(data->dev,
1094                                 "failed to read calibration coefficients\n");
1095                         goto out_disable_vdda;
1096                 }
1097         } else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) {
1098                 ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id);
1099                 if (ret < 0) {
1100                         dev_err(data->dev,
1101                                 "failed to read calibration coefficients\n");
1102                         goto out_disable_vdda;
1103                 }
1104         }
1105 
1106         /*
1107          * Attempt to grab an optional EOC IRQ - only the BMP085 has this
1108          * however as it happens, the BMP085 shares the chip ID of BMP180
1109          * so we look for an IRQ if we have that.
1110          */
1111         if (irq > 0 || (chip_id  == BMP180_CHIP_ID)) {
1112                 ret = bmp085_fetch_eoc_irq(dev, name, irq, data);
1113                 if (ret)
1114                         goto out_disable_vdda;
1115         }
1116 
1117         /* Enable runtime PM */
1118         pm_runtime_get_noresume(dev);
1119         pm_runtime_set_active(dev);
1120         pm_runtime_enable(dev);
1121         /*
1122          * Set autosuspend to two orders of magnitude larger than the
1123          * start-up time.
1124          */
1125         pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10);
1126         pm_runtime_use_autosuspend(dev);
1127         pm_runtime_put(dev);
1128 
1129         ret = iio_device_register(indio_dev);
1130         if (ret)
1131                 goto out_runtime_pm_disable;
1132 
1133 
1134         return 0;
1135 
1136 out_runtime_pm_disable:
1137         pm_runtime_get_sync(data->dev);
1138         pm_runtime_put_noidle(data->dev);
1139         pm_runtime_disable(data->dev);
1140 out_disable_vdda:
1141         regulator_disable(data->vdda);
1142 out_disable_vddd:
1143         regulator_disable(data->vddd);
1144         return ret;
1145 }
1146 EXPORT_SYMBOL(bmp280_common_probe);
1147 
1148 int bmp280_common_remove(struct device *dev)
1149 {
1150         struct iio_dev *indio_dev = dev_get_drvdata(dev);
1151         struct bmp280_data *data = iio_priv(indio_dev);
1152 
1153         iio_device_unregister(indio_dev);
1154         pm_runtime_get_sync(data->dev);
1155         pm_runtime_put_noidle(data->dev);
1156         pm_runtime_disable(data->dev);
1157         regulator_disable(data->vdda);
1158         regulator_disable(data->vddd);
1159         return 0;
1160 }
1161 EXPORT_SYMBOL(bmp280_common_remove);
1162 
1163 #ifdef CONFIG_PM
1164 static int bmp280_runtime_suspend(struct device *dev)
1165 {
1166         struct iio_dev *indio_dev = dev_get_drvdata(dev);
1167         struct bmp280_data *data = iio_priv(indio_dev);
1168         int ret;
1169 
1170         ret = regulator_disable(data->vdda);
1171         if (ret)
1172                 return ret;
1173         return regulator_disable(data->vddd);
1174 }
1175 
1176 static int bmp280_runtime_resume(struct device *dev)
1177 {
1178         struct iio_dev *indio_dev = dev_get_drvdata(dev);
1179         struct bmp280_data *data = iio_priv(indio_dev);
1180         int ret;
1181 
1182         ret = regulator_enable(data->vddd);
1183         if (ret)
1184                 return ret;
1185         ret = regulator_enable(data->vdda);
1186         if (ret)
1187                 return ret;
1188         usleep_range(data->start_up_time, data->start_up_time + 100);
1189         return data->chip_info->chip_config(data);
1190 }
1191 #endif /* CONFIG_PM */
1192 
1193 const struct dev_pm_ops bmp280_dev_pm_ops = {
1194         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1195                                 pm_runtime_force_resume)
1196         SET_RUNTIME_PM_OPS(bmp280_runtime_suspend,
1197                            bmp280_runtime_resume, NULL)
1198 };
1199 EXPORT_SYMBOL(bmp280_dev_pm_ops);
1200 
1201 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1202 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
1203 MODULE_LICENSE("GPL v2");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/iio/pressure/bmp280-core.c

DEFINITIONS
