?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / iio / pressure / bmp280-core.c
blob29c209cc1108e2e573fb446a5aa60bcb0b379f22
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 static const char *const bmp280_supply_names[] = {
78 "vddd", "vdda"
79 };
80
81 #define BMP280_NUM_SUPPLIES ARRAY_SIZE(bmp280_supply_names)
82
83 struct bmp280_data {
84 struct device *dev;
85 struct mutex lock;
86 struct regmap *regmap;
87 struct completion done;
88 bool use_eoc;
89 const struct bmp280_chip_info *chip_info;
90 union {
91 struct bmp180_calib bmp180;
92 struct bmp280_calib bmp280;
93 } calib;
94 struct regulator_bulk_data supplies[BMP280_NUM_SUPPLIES];
95 unsigned int start_up_time; /* in microseconds */
96
97 /* log of base 2 of oversampling rate */
98 u8 oversampling_press;
99 u8 oversampling_temp;
100 u8 oversampling_humid;
101
102 /*
103 * Carryover value from temperature conversion, used in pressure
104 * calculation.
105 */
106 s32 t_fine;
107 };
108
109 struct bmp280_chip_info {
110 const int *oversampling_temp_avail;
111 int num_oversampling_temp_avail;
112
113 const int *oversampling_press_avail;
114 int num_oversampling_press_avail;
115
116 const int *oversampling_humid_avail;
117 int num_oversampling_humid_avail;
118
119 int (*chip_config)(struct bmp280_data *);
120 int (*read_temp)(struct bmp280_data *, int *);
121 int (*read_press)(struct bmp280_data *, int *, int *);
122 int (*read_humid)(struct bmp280_data *, int *, int *);
123 };
124
125 /*
126 * These enums are used for indexing into the array of compensation
127 * parameters for BMP280.
128 */
129 enum { T1, T2, T3 };
130 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 };
131
132 static const struct iio_chan_spec bmp280_channels[] = {
133 {
134 .type = IIO_PRESSURE,
135 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
136 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
137 },
138 {
139 .type = IIO_TEMP,
140 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
141 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
142 },
143 {
144 .type = IIO_HUMIDITYRELATIVE,
145 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
146 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
147 },
148 };
149
150 static int bmp280_read_calib(struct bmp280_data *data,
151 struct bmp280_calib *calib,
152 unsigned int chip)
153 {
154 int ret;
155 unsigned int tmp;
156 __le16 l16;
157 __be16 b16;
158 struct device *dev = data->dev;
159 __le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
160 __le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
161
162 /* Read temperature calibration values. */
163 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
164 t_buf, BMP280_COMP_TEMP_REG_COUNT);
165 if (ret < 0) {
166 dev_err(data->dev,
167 "failed to read temperature calibration parameters\n");
168 return ret;
169 }
170
171 /* Toss the temperature calibration data into the entropy pool */
172 add_device_randomness(t_buf, sizeof(t_buf));
173
174 calib->T1 = le16_to_cpu(t_buf[T1]);
175 calib->T2 = le16_to_cpu(t_buf[T2]);
176 calib->T3 = le16_to_cpu(t_buf[T3]);
177
178 /* Read pressure calibration values. */
179 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
180 p_buf, BMP280_COMP_PRESS_REG_COUNT);
181 if (ret < 0) {
182 dev_err(data->dev,
183 "failed to read pressure calibration parameters\n");
184 return ret;
185 }
186
187 /* Toss the pressure calibration data into the entropy pool */
188 add_device_randomness(p_buf, sizeof(p_buf));
189
190 calib->P1 = le16_to_cpu(p_buf[P1]);
191 calib->P2 = le16_to_cpu(p_buf[P2]);
192 calib->P3 = le16_to_cpu(p_buf[P3]);
193 calib->P4 = le16_to_cpu(p_buf[P4]);
194 calib->P5 = le16_to_cpu(p_buf[P5]);
195 calib->P6 = le16_to_cpu(p_buf[P6]);
196 calib->P7 = le16_to_cpu(p_buf[P7]);
197 calib->P8 = le16_to_cpu(p_buf[P8]);
198 calib->P9 = le16_to_cpu(p_buf[P9]);
199
200 /*
201 * Read humidity calibration values.
202 * Due to some odd register addressing we cannot just
203 * do a big bulk read. Instead, we have to read each Hx
204 * value separately and sometimes do some bit shifting...
205 * Humidity data is only available on BME280.
206 */
207 if (chip != BME280_CHIP_ID)
208 return 0;
209
210 ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp);
211 if (ret < 0) {
212 dev_err(dev, "failed to read H1 comp value\n");
213 return ret;
214 }
215 calib->H1 = tmp;
216
217 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &l16, 2);
218 if (ret < 0) {
219 dev_err(dev, "failed to read H2 comp value\n");
220 return ret;
221 }
222 calib->H2 = sign_extend32(le16_to_cpu(l16), 15);
223
224 ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp);
225 if (ret < 0) {
226 dev_err(dev, "failed to read H3 comp value\n");
227 return ret;
228 }
229 calib->H3 = tmp;
230
231 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &b16, 2);
232 if (ret < 0) {
233 dev_err(dev, "failed to read H4 comp value\n");
234 return ret;
235 }
236 calib->H4 = sign_extend32(((be16_to_cpu(b16) >> 4) & 0xff0) |
237 (be16_to_cpu(b16) & 0xf), 11);
238
239 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &l16, 2);
240 if (ret < 0) {
241 dev_err(dev, "failed to read H5 comp value\n");
242 return ret;
243 }
244 calib->H5 = sign_extend32(((le16_to_cpu(l16) >> 4) & 0xfff), 11);
245
246 ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
247 if (ret < 0) {
248 dev_err(dev, "failed to read H6 comp value\n");
249 return ret;
250 }
251 calib->H6 = sign_extend32(tmp, 7);
252
253 return 0;
254 }
255 /*
256 * Returns humidity in percent, resolution is 0.01 percent. Output value of
257 * "47445" represents 47445/1024 = 46.333 %RH.
258 *
259 * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
260 */
261 static u32 bmp280_compensate_humidity(struct bmp280_data *data,
262 s32 adc_humidity)
263 {
264 s32 var;
265 struct bmp280_calib *calib = &data->calib.bmp280;
266
267 var = ((s32)data->t_fine) - (s32)76800;
268 var = ((((adc_humidity << 14) - (calib->H4 << 20) - (calib->H5 * var))
269 + (s32)16384) >> 15) * (((((((var * calib->H6) >> 10)
270 * (((var * (s32)calib->H3) >> 11) + (s32)32768)) >> 10)
271 + (s32)2097152) * calib->H2 + 8192) >> 14);
272 var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4;
273
274 return var >> 12;
275 };
276
277 /*
278 * Returns temperature in DegC, resolution is 0.01 DegC. Output value of
279 * "5123" equals 51.23 DegC. t_fine carries fine temperature as global
280 * value.
281 *
282 * Taken from datasheet, Section 3.11.3, "Compensation formula".
283 */
284 static s32 bmp280_compensate_temp(struct bmp280_data *data,
285 s32 adc_temp)
286 {
287 s32 var1, var2;
288 struct bmp280_calib *calib = &data->calib.bmp280;
289
290 var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) *
291 ((s32)calib->T2)) >> 11;
292 var2 = (((((adc_temp >> 4) - ((s32)calib->T1)) *
293 ((adc_temp >> 4) - ((s32)calib->T1))) >> 12) *
294 ((s32)calib->T3)) >> 14;
295 data->t_fine = var1 + var2;
296
297 return (data->t_fine * 5 + 128) >> 8;
298 }
299
300 /*
301 * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24
302 * integer bits and 8 fractional bits). Output value of "24674867"
303 * represents 24674867/256 = 96386.2 Pa = 963.862 hPa
304 *
305 * Taken from datasheet, Section 3.11.3, "Compensation formula".
306 */
307 static u32 bmp280_compensate_press(struct bmp280_data *data,
308 s32 adc_press)
309 {
310 s64 var1, var2, p;
311 struct bmp280_calib *calib = &data->calib.bmp280;
312
313 var1 = ((s64)data->t_fine) - 128000;
314 var2 = var1 * var1 * (s64)calib->P6;
315 var2 += (var1 * (s64)calib->P5) << 17;
316 var2 += ((s64)calib->P4) << 35;
317 var1 = ((var1 * var1 * (s64)calib->P3) >> 8) +
318 ((var1 * (s64)calib->P2) << 12);
319 var1 = ((((s64)1) << 47) + var1) * ((s64)calib->P1) >> 33;
320
321 if (var1 == 0)
322 return 0;
323
324 p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
325 p = div64_s64(p, var1);
326 var1 = (((s64)calib->P9) * (p >> 13) * (p >> 13)) >> 25;
327 var2 = ((s64)(calib->P8) * p) >> 19;
328 p = ((p + var1 + var2) >> 8) + (((s64)calib->P7) << 4);
329
330 return (u32)p;
331 }
332
333 static int bmp280_read_temp(struct bmp280_data *data,
334 int *val)
335 {
336 int ret;
337 __be32 tmp = 0;
338 s32 adc_temp, comp_temp;
339
340 ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
341 (u8 *) &tmp, 3);
342 if (ret < 0) {
343 dev_err(data->dev, "failed to read temperature\n");
344 return ret;
345 }
346
347 adc_temp = be32_to_cpu(tmp) >> 12;
348 if (adc_temp == BMP280_TEMP_SKIPPED) {
349 /* reading was skipped */
350 dev_err(data->dev, "reading temperature skipped\n");
351 return -EIO;
352 }
353 comp_temp = bmp280_compensate_temp(data, adc_temp);
354
355 /*
356 * val might be NULL if we're called by the read_press routine,
357 * who only cares about the carry over t_fine value.
358 */
359 if (val) {
360 *val = comp_temp * 10;
361 return IIO_VAL_INT;
362 }
363
364 return 0;
365 }
366
367 static int bmp280_read_press(struct bmp280_data *data,
368 int *val, int *val2)
369 {
370 int ret;
371 __be32 tmp = 0;
372 s32 adc_press;
373 u32 comp_press;
374
375 /* Read and compensate temperature so we get a reading of t_fine. */
376 ret = bmp280_read_temp(data, NULL);
377 if (ret < 0)
378 return ret;
379
380 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
381 (u8 *) &tmp, 3);
382 if (ret < 0) {
383 dev_err(data->dev, "failed to read pressure\n");
384 return ret;
385 }
386
387 adc_press = be32_to_cpu(tmp) >> 12;
388 if (adc_press == BMP280_PRESS_SKIPPED) {
389 /* reading was skipped */
390 dev_err(data->dev, "reading pressure skipped\n");
391 return -EIO;
392 }
393 comp_press = bmp280_compensate_press(data, adc_press);
394
395 *val = comp_press;
396 *val2 = 256000;
397
398 return IIO_VAL_FRACTIONAL;
399 }
400
401 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
402 {
403 int ret;
404 __be16 tmp = 0;
405 s32 adc_humidity;
406 u32 comp_humidity;
407
408 /* Read and compensate temperature so we get a reading of t_fine. */
409 ret = bmp280_read_temp(data, NULL);
410 if (ret < 0)
411 return ret;
412
413 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
414 (u8 *) &tmp, 2);
415 if (ret < 0) {
416 dev_err(data->dev, "failed to read humidity\n");
417 return ret;
418 }
419
420 adc_humidity = be16_to_cpu(tmp);
421 if (adc_humidity == BMP280_HUMIDITY_SKIPPED) {
422 /* reading was skipped */
423 dev_err(data->dev, "reading humidity skipped\n");
424 return -EIO;
425 }
426 comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
427
428 *val = comp_humidity * 1000 / 1024;
429
430 return IIO_VAL_INT;
431 }
432
433 static int bmp280_read_raw(struct iio_dev *indio_dev,
434 struct iio_chan_spec const *chan,
435 int *val, int *val2, long mask)
436 {
437 int ret;
438 struct bmp280_data *data = iio_priv(indio_dev);
439
440 pm_runtime_get_sync(data->dev);
441 mutex_lock(&data->lock);
442
443 switch (mask) {
444 case IIO_CHAN_INFO_PROCESSED:
445 switch (chan->type) {
446 case IIO_HUMIDITYRELATIVE:
447 ret = data->chip_info->read_humid(data, val, val2);
448 break;
449 case IIO_PRESSURE:
450 ret = data->chip_info->read_press(data, val, val2);
451 break;
452 case IIO_TEMP:
453 ret = data->chip_info->read_temp(data, val);
454 break;
455 default:
456 ret = -EINVAL;
457 break;
458 }
459 break;
460 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
461 switch (chan->type) {
462 case IIO_HUMIDITYRELATIVE:
463 *val = 1 << data->oversampling_humid;
464 ret = IIO_VAL_INT;
465 break;
466 case IIO_PRESSURE:
467 *val = 1 << data->oversampling_press;
468 ret = IIO_VAL_INT;
469 break;
470 case IIO_TEMP:
471 *val = 1 << data->oversampling_temp;
472 ret = IIO_VAL_INT;
473 break;
474 default:
475 ret = -EINVAL;
476 break;
477 }
478 break;
479 default:
480 ret = -EINVAL;
481 break;
482 }
483
484 mutex_unlock(&data->lock);
485 pm_runtime_mark_last_busy(data->dev);
486 pm_runtime_put_autosuspend(data->dev);
487
488 return ret;
489 }
490
491 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
492 int val)
493 {
494 int i;
495 const int *avail = data->chip_info->oversampling_humid_avail;
496 const int n = data->chip_info->num_oversampling_humid_avail;
497
498 for (i = 0; i < n; i++) {
499 if (avail[i] == val) {
500 data->oversampling_humid = ilog2(val);
501
502 return data->chip_info->chip_config(data);
503 }
504 }
505 return -EINVAL;
506 }
507
508 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
509 int val)
510 {
511 int i;
512 const int *avail = data->chip_info->oversampling_temp_avail;
513 const int n = data->chip_info->num_oversampling_temp_avail;
514
515 for (i = 0; i < n; i++) {
516 if (avail[i] == val) {
517 data->oversampling_temp = ilog2(val);
518
519 return data->chip_info->chip_config(data);
520 }
521 }
522 return -EINVAL;
523 }
524
525 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
526 int val)
527 {
528 int i;
529 const int *avail = data->chip_info->oversampling_press_avail;
530 const int n = data->chip_info->num_oversampling_press_avail;
531
532 for (i = 0; i < n; i++) {
533 if (avail[i] == val) {
534 data->oversampling_press = ilog2(val);
535
536 return data->chip_info->chip_config(data);
537 }
538 }
539 return -EINVAL;
540 }
541
542 static int bmp280_write_raw(struct iio_dev *indio_dev,
543 struct iio_chan_spec const *chan,
544 int val, int val2, long mask)
545 {
546 int ret = 0;
547 struct bmp280_data *data = iio_priv(indio_dev);
548
549 switch (mask) {
550 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
551 pm_runtime_get_sync(data->dev);
552 mutex_lock(&data->lock);
553 switch (chan->type) {
554 case IIO_HUMIDITYRELATIVE:
555 ret = bmp280_write_oversampling_ratio_humid(data, val);
556 break;
557 case IIO_PRESSURE:
558 ret = bmp280_write_oversampling_ratio_press(data, val);
559 break;
560 case IIO_TEMP:
561 ret = bmp280_write_oversampling_ratio_temp(data, val);
562 break;
563 default:
564 ret = -EINVAL;
565 break;
566 }
567 mutex_unlock(&data->lock);
568 pm_runtime_mark_last_busy(data->dev);
569 pm_runtime_put_autosuspend(data->dev);
570 break;
571 default:
572 return -EINVAL;
573 }
574
575 return ret;
576 }
577
578 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n)
579 {
580 size_t len = 0;
581 int i;
582
583 for (i = 0; i < n; i++)
584 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]);
585
586 buf[len - 1] = '\n';
587
588 return len;
589 }
590
591 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev,
592 struct device_attribute *attr, char *buf)
593 {
594 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
595
596 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail,
597 data->chip_info->num_oversampling_temp_avail);
598 }
599
600 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev,
601 struct device_attribute *attr, char *buf)
602 {
603 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
604
605 return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail,
606 data->chip_info->num_oversampling_press_avail);
607 }
608
609 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available,
610 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0);
611
612 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available,
613 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0);
614
615 static struct attribute *bmp280_attributes[] = {
616 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
617 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr,
618 NULL,
619 };
620
621 static const struct attribute_group bmp280_attrs_group = {
622 .attrs = bmp280_attributes,
623 };
624
625 static const struct iio_info bmp280_info = {
626 .read_raw = &bmp280_read_raw,
627 .write_raw = &bmp280_write_raw,
628 .attrs = &bmp280_attrs_group,
629 };
630
631 static int bmp280_chip_config(struct bmp280_data *data)
632 {
633 int ret;
634 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
635 BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
636
637 ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
638 BMP280_OSRS_TEMP_MASK |
639 BMP280_OSRS_PRESS_MASK |
640 BMP280_MODE_MASK,
641 osrs | BMP280_MODE_NORMAL);
642 if (ret < 0) {
643 dev_err(data->dev,
644 "failed to write ctrl_meas register\n");
645 return ret;
646 }
647
648 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG,
649 BMP280_FILTER_MASK,
650 BMP280_FILTER_4X);
651 if (ret < 0) {
652 dev_err(data->dev,
653 "failed to write config register\n");
654 return ret;
655 }
656
657 return ret;
658 }
659
660 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 };
661
662 static const struct bmp280_chip_info bmp280_chip_info = {
663 .oversampling_temp_avail = bmp280_oversampling_avail,
664 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
665
666 .oversampling_press_avail = bmp280_oversampling_avail,
667 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
668
669 .chip_config = bmp280_chip_config,
670 .read_temp = bmp280_read_temp,
671 .read_press = bmp280_read_press,
672 };
673
674 static int bme280_chip_config(struct bmp280_data *data)
675 {
676 int ret;
677 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
678
679 /*
680 * Oversampling of humidity must be set before oversampling of
681 * temperature/pressure is set to become effective.
682 */
683 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
684 BMP280_OSRS_HUMIDITY_MASK, osrs);
685
686 if (ret < 0)
687 return ret;
688
689 return bmp280_chip_config(data);
690 }
691
692 static const struct bmp280_chip_info bme280_chip_info = {
693 .oversampling_temp_avail = bmp280_oversampling_avail,
694 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
695
696 .oversampling_press_avail = bmp280_oversampling_avail,
697 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
698
699 .oversampling_humid_avail = bmp280_oversampling_avail,
700 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
701
702 .chip_config = bme280_chip_config,
703 .read_temp = bmp280_read_temp,
704 .read_press = bmp280_read_press,
705 .read_humid = bmp280_read_humid,
706 };
707
708 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
709 {
710 int ret;
711 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
712 unsigned int delay_us;
713 unsigned int ctrl;
714
715 if (data->use_eoc)
716 init_completion(&data->done);
717
718 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas);
719 if (ret)
720 return ret;
721
722 if (data->use_eoc) {
723 /*
724 * If we have a completion interrupt, use it, wait up to
725 * 100ms. The longest conversion time listed is 76.5 ms for
726 * advanced resolution mode.
727 */
728 ret = wait_for_completion_timeout(&data->done,
729 1 + msecs_to_jiffies(100));
730 if (!ret)
731 dev_err(data->dev, "timeout waiting for completion\n");
732 } else {
733 if (ctrl_meas == BMP180_MEAS_TEMP)
734 delay_us = 4500;
735 else
736 delay_us =
737 conversion_time_max[data->oversampling_press];
738
739 usleep_range(delay_us, delay_us + 1000);
740 }
741
742 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl);
743 if (ret)
744 return ret;
745
746 /* The value of this bit reset to "0" after conversion is complete */
747 if (ctrl & BMP180_MEAS_SCO)
748 return -EIO;
749
750 return 0;
751 }
752
753 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
754 {
755 int ret;
756 __be16 tmp = 0;
757
758 ret = bmp180_measure(data, BMP180_MEAS_TEMP);
759 if (ret)
760 return ret;
761
762 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2);
763 if (ret)
764 return ret;
765
766 *val = be16_to_cpu(tmp);
767
768 return 0;
769 }
770
771 static int bmp180_read_calib(struct bmp280_data *data,
772 struct bmp180_calib *calib)
773 {
774 int ret;
775 int i;
776 __be16 buf[BMP180_REG_CALIB_COUNT / 2];
777
778 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
779 sizeof(buf));
780
781 if (ret < 0)
782 return ret;
783
784 /* None of the words has the value 0 or 0xFFFF */
785 for (i = 0; i < ARRAY_SIZE(buf); i++) {
786 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff))
787 return -EIO;
788 }
789
790 /* Toss the calibration data into the entropy pool */
791 add_device_randomness(buf, sizeof(buf));
792
793 calib->AC1 = be16_to_cpu(buf[AC1]);
794 calib->AC2 = be16_to_cpu(buf[AC2]);
795 calib->AC3 = be16_to_cpu(buf[AC3]);
796 calib->AC4 = be16_to_cpu(buf[AC4]);
797 calib->AC5 = be16_to_cpu(buf[AC5]);
798 calib->AC6 = be16_to_cpu(buf[AC6]);
799 calib->B1 = be16_to_cpu(buf[B1]);
800 calib->B2 = be16_to_cpu(buf[B2]);
801 calib->MB = be16_to_cpu(buf[MB]);
802 calib->MC = be16_to_cpu(buf[MC]);
803 calib->MD = be16_to_cpu(buf[MD]);
804
805 return 0;
806 }
807
808 /*
809 * Returns temperature in DegC, resolution is 0.1 DegC.
810 * t_fine carries fine temperature as global value.
811 *
812 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
813 */
814 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
815 {
816 s32 x1, x2;
817 struct bmp180_calib *calib = &data->calib.bmp180;
818
819 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15;
820 x2 = (calib->MC << 11) / (x1 + calib->MD);
821 data->t_fine = x1 + x2;
822
823 return (data->t_fine + 8) >> 4;
824 }
825
826 static int bmp180_read_temp(struct bmp280_data *data, int *val)
827 {
828 int ret;
829 s32 adc_temp, comp_temp;
830
831 ret = bmp180_read_adc_temp(data, &adc_temp);
832 if (ret)
833 return ret;
834
835 comp_temp = bmp180_compensate_temp(data, adc_temp);
836
837 /*
838 * val might be NULL if we're called by the read_press routine,
839 * who only cares about the carry over t_fine value.
840 */
841 if (val) {
842 *val = comp_temp * 100;
843 return IIO_VAL_INT;
844 }
845
846 return 0;
847 }
848
849 static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
850 {
851 int ret;
852 __be32 tmp = 0;
853 u8 oss = data->oversampling_press;
854
855 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
856 if (ret)
857 return ret;
858
859 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3);
860 if (ret)
861 return ret;
862
863 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
864
865 return 0;
866 }
867
868 /*
869 * Returns pressure in Pa, resolution is 1 Pa.
870 *
871 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
872 */
873 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
874 {
875 s32 x1, x2, x3, p;
876 s32 b3, b6;
877 u32 b4, b7;
878 s32 oss = data->oversampling_press;
879 struct bmp180_calib *calib = &data->calib.bmp180;
880
881 b6 = data->t_fine - 4000;
882 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
883 x2 = calib->AC2 * b6 >> 11;
884 x3 = x1 + x2;
885 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4;
886 x1 = calib->AC3 * b6 >> 13;
887 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16;
888 x3 = (x1 + x2 + 2) >> 2;
889 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15;
890 b7 = ((u32)adc_press - b3) * (50000 >> oss);
891 if (b7 < 0x80000000)
892 p = (b7 * 2) / b4;
893 else
894 p = (b7 / b4) * 2;
895
896 x1 = (p >> 8) * (p >> 8);
897 x1 = (x1 * 3038) >> 16;
898 x2 = (-7357 * p) >> 16;
899
900 return p + ((x1 + x2 + 3791) >> 4);
901 }
902
903 static int bmp180_read_press(struct bmp280_data *data,
904 int *val, int *val2)
905 {
906 int ret;
907 s32 adc_press;
908 u32 comp_press;
909
910 /* Read and compensate temperature so we get a reading of t_fine. */
911 ret = bmp180_read_temp(data, NULL);
912 if (ret)
913 return ret;
914
915 ret = bmp180_read_adc_press(data, &adc_press);
916 if (ret)
917 return ret;
918
919 comp_press = bmp180_compensate_press(data, adc_press);
920
921 *val = comp_press;
922 *val2 = 1000;
923
924 return IIO_VAL_FRACTIONAL;
925 }
926
927 static int bmp180_chip_config(struct bmp280_data *data)
928 {
929 return 0;
930 }
931
932 static const int bmp180_oversampling_temp_avail[] = { 1 };
933 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 };
934
935 static const struct bmp280_chip_info bmp180_chip_info = {
936 .oversampling_temp_avail = bmp180_oversampling_temp_avail,
937 .num_oversampling_temp_avail =
938 ARRAY_SIZE(bmp180_oversampling_temp_avail),
939
940 .oversampling_press_avail = bmp180_oversampling_press_avail,
941 .num_oversampling_press_avail =
942 ARRAY_SIZE(bmp180_oversampling_press_avail),
943
944 .chip_config = bmp180_chip_config,
945 .read_temp = bmp180_read_temp,
946 .read_press = bmp180_read_press,
947 };
948
949 static irqreturn_t bmp085_eoc_irq(int irq, void *d)
950 {
951 struct bmp280_data *data = d;
952
953 complete(&data->done);
954
955 return IRQ_HANDLED;
956 }
957
958 static int bmp085_fetch_eoc_irq(struct device *dev,
959 const char *name,
960 int irq,
961 struct bmp280_data *data)
962 {
963 unsigned long irq_trig;
964 int ret;
965
966 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
967 if (irq_trig != IRQF_TRIGGER_RISING) {
968 dev_err(dev, "non-rising trigger given for EOC interrupt, "
969 "trying to enforce it\n");
970 irq_trig = IRQF_TRIGGER_RISING;
971 }
972 ret = devm_request_threaded_irq(dev,
973 irq,
974 bmp085_eoc_irq,
975 NULL,
976 irq_trig,
977 name,
978 data);
979 if (ret) {
980 /* Bail out without IRQ but keep the driver in place */
981 dev_err(dev, "unable to request DRDY IRQ\n");
982 return 0;
983 }
984
985 data->use_eoc = true;
986 return 0;
987 }
988
989 static void bmp280_pm_disable(void *data)
990 {
991 struct device *dev = data;
992
993 pm_runtime_get_sync(dev);
994 pm_runtime_put_noidle(dev);
995 pm_runtime_disable(dev);
996 }
997
998 static void bmp280_regulators_disable(void *data)
999 {
1000 struct regulator_bulk_data *supplies = data;
1001
1002 regulator_bulk_disable(BMP280_NUM_SUPPLIES, supplies);
1003 }
1004
1005 int bmp280_common_probe(struct device *dev,
1006 struct regmap *regmap,
1007 unsigned int chip,
1008 const char *name,
1009 int irq)
1010 {
1011 int ret;
1012 struct iio_dev *indio_dev;
1013 struct bmp280_data *data;
1014 unsigned int chip_id;
1015 struct gpio_desc *gpiod;
1016
1017 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
1018 if (!indio_dev)
1019 return -ENOMEM;
1020
1021 data = iio_priv(indio_dev);
1022 mutex_init(&data->lock);
1023 data->dev = dev;
1024
1025 indio_dev->dev.parent = dev;
1026 indio_dev->name = name;
1027 indio_dev->channels = bmp280_channels;
1028 indio_dev->info = &bmp280_info;
1029 indio_dev->modes = INDIO_DIRECT_MODE;
1030
1031 switch (chip) {
1032 case BMP180_CHIP_ID:
1033 indio_dev->num_channels = 2;
1034 data->chip_info = &bmp180_chip_info;
1035 data->oversampling_press = ilog2(8);
1036 data->oversampling_temp = ilog2(1);
1037 data->start_up_time = 10000;
1038 break;
1039 case BMP280_CHIP_ID:
1040 indio_dev->num_channels = 2;
1041 data->chip_info = &bmp280_chip_info;
1042 data->oversampling_press = ilog2(16);
1043 data->oversampling_temp = ilog2(2);
1044 data->start_up_time = 2000;
1045 break;
1046 case BME280_CHIP_ID:
1047 indio_dev->num_channels = 3;
1048 data->chip_info = &bme280_chip_info;
1049 data->oversampling_press = ilog2(16);
1050 data->oversampling_humid = ilog2(16);
1051 data->oversampling_temp = ilog2(2);
1052 data->start_up_time = 2000;
1053 break;
1054 default:
1055 return -EINVAL;
1056 }
1057
1058 /* Bring up regulators */
1059 regulator_bulk_set_supply_names(data->supplies,
1060 bmp280_supply_names,
1061 BMP280_NUM_SUPPLIES);
1062
1063 ret = devm_regulator_bulk_get(dev,
1064 BMP280_NUM_SUPPLIES, data->supplies);
1065 if (ret) {
1066 dev_err(dev, "failed to get regulators\n");
1067 return ret;
1068 }
1069
1070 ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies);
1071 if (ret) {
1072 dev_err(dev, "failed to enable regulators\n");
1073 return ret;
1074 }
1075
1076 ret = devm_add_action_or_reset(dev, bmp280_regulators_disable,
1077 data->supplies);
1078 if (ret)
1079 return ret;
1080
1081 /* Wait to make sure we started up properly */
1082 usleep_range(data->start_up_time, data->start_up_time + 100);
1083
1084 /* Bring chip out of reset if there is an assigned GPIO line */
1085 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
1086 /* Deassert the signal */
1087 if (!IS_ERR(gpiod)) {
1088 dev_info(dev, "release reset\n");
1089 gpiod_set_value(gpiod, 0);
1090 }
1091
1092 data->regmap = regmap;
1093 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
1094 if (ret < 0)
1095 return ret;
1096 if (chip_id != chip) {
1097 dev_err(dev, "bad chip id: expected %x got %x\n",
1098 chip, chip_id);
1099 return -EINVAL;
1100 }
1101
1102 ret = data->chip_info->chip_config(data);
1103 if (ret < 0)
1104 return ret;
1105
1106 dev_set_drvdata(dev, indio_dev);
1107
1108 /*
1109 * Some chips have calibration parameters "programmed into the devices'
1110 * non-volatile memory during production". Let's read them out at probe
1111 * time once. They will not change.
1112 */
1113 if (chip_id == BMP180_CHIP_ID) {
1114 ret = bmp180_read_calib(data, &data->calib.bmp180);
1115 if (ret < 0) {
1116 dev_err(data->dev,
1117 "failed to read calibration coefficients\n");
1118 return ret;
1119 }
1120 } else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) {
1121 ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id);
1122 if (ret < 0) {
1123 dev_err(data->dev,
1124 "failed to read calibration coefficients\n");
1125 return ret;
1126 }
1127 }
1128
1129 /*
1130 * Attempt to grab an optional EOC IRQ - only the BMP085 has this
1131 * however as it happens, the BMP085 shares the chip ID of BMP180
1132 * so we look for an IRQ if we have that.
1133 */
1134 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) {
1135 ret = bmp085_fetch_eoc_irq(dev, name, irq, data);
1136 if (ret)
1137 return ret;
1138 }
1139
1140 /* Enable runtime PM */
1141 pm_runtime_get_noresume(dev);
1142 pm_runtime_set_active(dev);
1143 pm_runtime_enable(dev);
1144 /*
1145 * Set autosuspend to two orders of magnitude larger than the
1146 * start-up time.
1147 */
1148 pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10);
1149 pm_runtime_use_autosuspend(dev);
1150 pm_runtime_put(dev);
1151
1152 ret = devm_add_action_or_reset(dev, bmp280_pm_disable, dev);
1153 if (ret)
1154 return ret;
1155
1156 return devm_iio_device_register(dev, indio_dev);
1157 }
1158 EXPORT_SYMBOL(bmp280_common_probe);
1159
1160 #ifdef CONFIG_PM
1161 static int bmp280_runtime_suspend(struct device *dev)
1162 {
1163 struct iio_dev *indio_dev = dev_get_drvdata(dev);
1164 struct bmp280_data *data = iio_priv(indio_dev);
1165
1166 return regulator_bulk_disable(BMP280_NUM_SUPPLIES, data->supplies);
1167 }
1168
1169 static int bmp280_runtime_resume(struct device *dev)
1170 {
1171 struct iio_dev *indio_dev = dev_get_drvdata(dev);
1172 struct bmp280_data *data = iio_priv(indio_dev);
1173 int ret;
1174
1175 ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies);
1176 if (ret)
1177 return ret;
1178 usleep_range(data->start_up_time, data->start_up_time + 100);
1179 return data->chip_info->chip_config(data);
1180 }
1181 #endif /* CONFIG_PM */
1182
1183 const struct dev_pm_ops bmp280_dev_pm_ops = {
1184 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1185 pm_runtime_force_resume)
1186 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend,
1187 bmp280_runtime_resume, NULL)
1188 };
1189 EXPORT_SYMBOL(bmp280_dev_pm_ops);
1190
1191 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1192 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
1193 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support