Merge remote-tracking branch 'omap_dss2/for-next'
[deliverable/linux.git] / drivers / iio / pressure / bmp280-core.c
1 /*
2 * Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>
3 * Copyright (c) 2012 Bosch Sensortec GmbH
4 * Copyright (c) 2012 Unixphere AB
5 * Copyright (c) 2014 Intel Corporation
6 * Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org>
7 *
8 * Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * Datasheet:
15 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf
16 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf
17 * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
18 */
19
20 #define pr_fmt(fmt) "bmp280: " fmt
21
22 #include <linux/device.h>
23 #include <linux/module.h>
24 #include <linux/regmap.h>
25 #include <linux/delay.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/gpio/consumer.h>
29 #include <linux/regulator/consumer.h>
30 #include <linux/interrupt.h>
31 #include <linux/irq.h> /* For irq_get_irq_data() */
32 #include <linux/completion.h>
33 #include <linux/pm_runtime.h>
34 #include <linux/random.h>
35
36 #include "bmp280.h"
37
38 /*
39 * These enums are used for indexing into the array of calibration
40 * coefficients for BMP180.
41 */
42 enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD };
43
44 struct bmp180_calib {
45 s16 AC1;
46 s16 AC2;
47 s16 AC3;
48 u16 AC4;
49 u16 AC5;
50 u16 AC6;
51 s16 B1;
52 s16 B2;
53 s16 MB;
54 s16 MC;
55 s16 MD;
56 };
57
58 struct bmp280_data {
59 struct device *dev;
60 struct mutex lock;
61 struct regmap *regmap;
62 struct completion done;
63 bool use_eoc;
64 const struct bmp280_chip_info *chip_info;
65 struct bmp180_calib calib;
66 struct regulator *vddd;
67 struct regulator *vdda;
68 unsigned int start_up_time; /* in milliseconds */
69
70 /* log of base 2 of oversampling rate */
71 u8 oversampling_press;
72 u8 oversampling_temp;
73 u8 oversampling_humid;
74
75 /*
76 * Carryover value from temperature conversion, used in pressure
77 * calculation.
78 */
79 s32 t_fine;
80 };
81
82 struct bmp280_chip_info {
83 const int *oversampling_temp_avail;
84 int num_oversampling_temp_avail;
85
86 const int *oversampling_press_avail;
87 int num_oversampling_press_avail;
88
89 const int *oversampling_humid_avail;
90 int num_oversampling_humid_avail;
91
92 int (*chip_config)(struct bmp280_data *);
93 int (*read_temp)(struct bmp280_data *, int *);
94 int (*read_press)(struct bmp280_data *, int *, int *);
95 int (*read_humid)(struct bmp280_data *, int *, int *);
96 };
97
98 /*
99 * These enums are used for indexing into the array of compensation
100 * parameters for BMP280.
101 */
102 enum { T1, T2, T3 };
103 enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 };
104
105 static const struct iio_chan_spec bmp280_channels[] = {
106 {
107 .type = IIO_PRESSURE,
108 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
109 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
110 },
111 {
112 .type = IIO_TEMP,
113 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
114 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
115 },
116 {
117 .type = IIO_HUMIDITYRELATIVE,
118 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
119 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
120 },
121 };
122
123 /*
124 * Returns humidity in percent, resolution is 0.01 percent. Output value of
125 * "47445" represents 47445/1024 = 46.333 %RH.
126 *
127 * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
128 */
129
130 static u32 bmp280_compensate_humidity(struct bmp280_data *data,
131 s32 adc_humidity)
132 {
133 struct device *dev = data->dev;
134 unsigned int H1, H3, tmp;
135 int H2, H4, H5, H6, ret, var;
136
137 ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &H1);
138 if (ret < 0) {
139 dev_err(dev, "failed to read H1 comp value\n");
140 return ret;
141 }
142
143 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2);
144 if (ret < 0) {
145 dev_err(dev, "failed to read H2 comp value\n");
146 return ret;
147 }
148 H2 = sign_extend32(le16_to_cpu(tmp), 15);
149
150 ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &H3);
151 if (ret < 0) {
152 dev_err(dev, "failed to read H3 comp value\n");
153 return ret;
154 }
155
156 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2);
157 if (ret < 0) {
158 dev_err(dev, "failed to read H4 comp value\n");
159 return ret;
160 }
161 H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) |
162 (be16_to_cpu(tmp) & 0xf), 11);
163
164 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2);
165 if (ret < 0) {
166 dev_err(dev, "failed to read H5 comp value\n");
167 return ret;
168 }
169 H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11);
170
171 ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
172 if (ret < 0) {
173 dev_err(dev, "failed to read H6 comp value\n");
174 return ret;
175 }
176 H6 = sign_extend32(tmp, 7);
177
178 var = ((s32)data->t_fine) - 76800;
179 var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var)) + 16384) >> 15)
180 * (((((((var * H6) >> 10) * (((var * H3) >> 11) + 32768)) >> 10)
181 + 2097152) * H2 + 8192) >> 14);
182 var -= ((((var >> 15) * (var >> 15)) >> 7) * H1) >> 4;
183
184 return var >> 12;
185 };
186
187 /*
188 * Returns temperature in DegC, resolution is 0.01 DegC. Output value of
189 * "5123" equals 51.23 DegC. t_fine carries fine temperature as global
190 * value.
191 *
192 * Taken from datasheet, Section 3.11.3, "Compensation formula".
193 */
194 static s32 bmp280_compensate_temp(struct bmp280_data *data,
195 s32 adc_temp)
196 {
197 int ret;
198 s32 var1, var2;
199 __le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
200
201 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
202 buf, BMP280_COMP_TEMP_REG_COUNT);
203 if (ret < 0) {
204 dev_err(data->dev,
205 "failed to read temperature calibration parameters\n");
206 return ret;
207 }
208
209 /*
210 * The double casts are necessary because le16_to_cpu returns an
211 * unsigned 16-bit value. Casting that value directly to a
212 * signed 32-bit will not do proper sign extension.
213 *
214 * Conversely, T1 and P1 are unsigned values, so they can be
215 * cast straight to the larger type.
216 */
217 var1 = (((adc_temp >> 3) - ((s32)le16_to_cpu(buf[T1]) << 1)) *
218 ((s32)(s16)le16_to_cpu(buf[T2]))) >> 11;
219 var2 = (((((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1]))) *
220 ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
221 ((s32)(s16)le16_to_cpu(buf[T3]))) >> 14;
222 data->t_fine = var1 + var2;
223
224 return (data->t_fine * 5 + 128) >> 8;
225 }
226
227 /*
228 * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24
229 * integer bits and 8 fractional bits). Output value of "24674867"
230 * represents 24674867/256 = 96386.2 Pa = 963.862 hPa
231 *
232 * Taken from datasheet, Section 3.11.3, "Compensation formula".
233 */
234 static u32 bmp280_compensate_press(struct bmp280_data *data,
235 s32 adc_press)
236 {
237 int ret;
238 s64 var1, var2, p;
239 __le16 buf[BMP280_COMP_PRESS_REG_COUNT / 2];
240
241 ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
242 buf, BMP280_COMP_PRESS_REG_COUNT);
243 if (ret < 0) {
244 dev_err(data->dev,
245 "failed to read pressure calibration parameters\n");
246 return ret;
247 }
248
249 var1 = ((s64)data->t_fine) - 128000;
250 var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
251 var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
252 var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
253 var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
254 ((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
255 var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;
256
257 if (var1 == 0)
258 return 0;
259
260 p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
261 p = div64_s64(p, var1);
262 var1 = (((s64)(s16)le16_to_cpu(buf[P9])) * (p >> 13) * (p >> 13)) >> 25;
263 var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
264 p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
265
266 return (u32)p;
267 }
268
269 static int bmp280_read_temp(struct bmp280_data *data,
270 int *val)
271 {
272 int ret;
273 __be32 tmp = 0;
274 s32 adc_temp, comp_temp;
275
276 ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
277 (u8 *) &tmp, 3);
278 if (ret < 0) {
279 dev_err(data->dev, "failed to read temperature\n");
280 return ret;
281 }
282
283 adc_temp = be32_to_cpu(tmp) >> 12;
284 comp_temp = bmp280_compensate_temp(data, adc_temp);
285
286 /*
287 * val might be NULL if we're called by the read_press routine,
288 * who only cares about the carry over t_fine value.
289 */
290 if (val) {
291 *val = comp_temp * 10;
292 return IIO_VAL_INT;
293 }
294
295 return 0;
296 }
297
298 static int bmp280_read_press(struct bmp280_data *data,
299 int *val, int *val2)
300 {
301 int ret;
302 __be32 tmp = 0;
303 s32 adc_press;
304 u32 comp_press;
305
306 /* Read and compensate temperature so we get a reading of t_fine. */
307 ret = bmp280_read_temp(data, NULL);
308 if (ret < 0)
309 return ret;
310
311 ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
312 (u8 *) &tmp, 3);
313 if (ret < 0) {
314 dev_err(data->dev, "failed to read pressure\n");
315 return ret;
316 }
317
318 adc_press = be32_to_cpu(tmp) >> 12;
319 comp_press = bmp280_compensate_press(data, adc_press);
320
321 *val = comp_press;
322 *val2 = 256000;
323
324 return IIO_VAL_FRACTIONAL;
325 }
326
327 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
328 {
329 int ret;
330 __be16 tmp = 0;
331 s32 adc_humidity;
332 u32 comp_humidity;
333
334 /* Read and compensate temperature so we get a reading of t_fine. */
335 ret = bmp280_read_temp(data, NULL);
336 if (ret < 0)
337 return ret;
338
339 ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
340 (u8 *) &tmp, 2);
341 if (ret < 0) {
342 dev_err(data->dev, "failed to read humidity\n");
343 return ret;
344 }
345
346 adc_humidity = be16_to_cpu(tmp);
347 comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
348
349 *val = comp_humidity;
350 *val2 = 1024;
351
352 return IIO_VAL_FRACTIONAL;
353 }
354
355 static int bmp280_read_raw(struct iio_dev *indio_dev,
356 struct iio_chan_spec const *chan,
357 int *val, int *val2, long mask)
358 {
359 int ret;
360 struct bmp280_data *data = iio_priv(indio_dev);
361
362 pm_runtime_get_sync(data->dev);
363 mutex_lock(&data->lock);
364
365 switch (mask) {
366 case IIO_CHAN_INFO_PROCESSED:
367 switch (chan->type) {
368 case IIO_HUMIDITYRELATIVE:
369 ret = data->chip_info->read_humid(data, val, val2);
370 break;
371 case IIO_PRESSURE:
372 ret = data->chip_info->read_press(data, val, val2);
373 break;
374 case IIO_TEMP:
375 ret = data->chip_info->read_temp(data, val);
376 break;
377 default:
378 ret = -EINVAL;
379 break;
380 }
381 break;
382 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
383 switch (chan->type) {
384 case IIO_HUMIDITYRELATIVE:
385 *val = 1 << data->oversampling_humid;
386 ret = IIO_VAL_INT;
387 break;
388 case IIO_PRESSURE:
389 *val = 1 << data->oversampling_press;
390 ret = IIO_VAL_INT;
391 break;
392 case IIO_TEMP:
393 *val = 1 << data->oversampling_temp;
394 ret = IIO_VAL_INT;
395 break;
396 default:
397 ret = -EINVAL;
398 break;
399 }
400 break;
401 default:
402 ret = -EINVAL;
403 break;
404 }
405
406 mutex_unlock(&data->lock);
407 pm_runtime_mark_last_busy(data->dev);
408 pm_runtime_put_autosuspend(data->dev);
409
410 return ret;
411 }
412
413 static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
414 int val)
415 {
416 int i;
417 const int *avail = data->chip_info->oversampling_humid_avail;
418 const int n = data->chip_info->num_oversampling_humid_avail;
419
420 for (i = 0; i < n; i++) {
421 if (avail[i] == val) {
422 data->oversampling_humid = ilog2(val);
423
424 return data->chip_info->chip_config(data);
425 }
426 }
427 return -EINVAL;
428 }
429
430 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
431 int val)
432 {
433 int i;
434 const int *avail = data->chip_info->oversampling_temp_avail;
435 const int n = data->chip_info->num_oversampling_temp_avail;
436
437 for (i = 0; i < n; i++) {
438 if (avail[i] == val) {
439 data->oversampling_temp = ilog2(val);
440
441 return data->chip_info->chip_config(data);
442 }
443 }
444 return -EINVAL;
445 }
446
447 static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
448 int val)
449 {
450 int i;
451 const int *avail = data->chip_info->oversampling_press_avail;
452 const int n = data->chip_info->num_oversampling_press_avail;
453
454 for (i = 0; i < n; i++) {
455 if (avail[i] == val) {
456 data->oversampling_press = ilog2(val);
457
458 return data->chip_info->chip_config(data);
459 }
460 }
461 return -EINVAL;
462 }
463
464 static int bmp280_write_raw(struct iio_dev *indio_dev,
465 struct iio_chan_spec const *chan,
466 int val, int val2, long mask)
467 {
468 int ret = 0;
469 struct bmp280_data *data = iio_priv(indio_dev);
470
471 switch (mask) {
472 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
473 pm_runtime_get_sync(data->dev);
474 mutex_lock(&data->lock);
475 switch (chan->type) {
476 case IIO_HUMIDITYRELATIVE:
477 ret = bmp280_write_oversampling_ratio_humid(data, val);
478 break;
479 case IIO_PRESSURE:
480 ret = bmp280_write_oversampling_ratio_press(data, val);
481 break;
482 case IIO_TEMP:
483 ret = bmp280_write_oversampling_ratio_temp(data, val);
484 break;
485 default:
486 ret = -EINVAL;
487 break;
488 }
489 mutex_unlock(&data->lock);
490 pm_runtime_mark_last_busy(data->dev);
491 pm_runtime_put_autosuspend(data->dev);
492 break;
493 default:
494 return -EINVAL;
495 }
496
497 return ret;
498 }
499
500 static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n)
501 {
502 size_t len = 0;
503 int i;
504
505 for (i = 0; i < n; i++)
506 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]);
507
508 buf[len - 1] = '\n';
509
510 return len;
511 }
512
513 static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev,
514 struct device_attribute *attr, char *buf)
515 {
516 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
517
518 return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail,
519 data->chip_info->num_oversampling_temp_avail);
520 }
521
522 static ssize_t bmp280_show_press_oversampling_avail(struct device *dev,
523 struct device_attribute *attr, char *buf)
524 {
525 struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
526
527 return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail,
528 data->chip_info->num_oversampling_press_avail);
529 }
530
531 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available,
532 S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0);
533
534 static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available,
535 S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0);
536
537 static struct attribute *bmp280_attributes[] = {
538 &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
539 &iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr,
540 NULL,
541 };
542
543 static const struct attribute_group bmp280_attrs_group = {
544 .attrs = bmp280_attributes,
545 };
546
547 static const struct iio_info bmp280_info = {
548 .driver_module = THIS_MODULE,
549 .read_raw = &bmp280_read_raw,
550 .write_raw = &bmp280_write_raw,
551 .attrs = &bmp280_attrs_group,
552 };
553
554 static int bmp280_chip_config(struct bmp280_data *data)
555 {
556 int ret;
557 u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
558 BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
559
560 ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_MEAS,
561 BMP280_OSRS_TEMP_MASK |
562 BMP280_OSRS_PRESS_MASK |
563 BMP280_MODE_MASK,
564 osrs | BMP280_MODE_NORMAL);
565 if (ret < 0) {
566 dev_err(data->dev,
567 "failed to write ctrl_meas register\n");
568 return ret;
569 }
570
571 ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG,
572 BMP280_FILTER_MASK,
573 BMP280_FILTER_4X);
574 if (ret < 0) {
575 dev_err(data->dev,
576 "failed to write config register\n");
577 return ret;
578 }
579
580 return ret;
581 }
582
583 static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 };
584
585 static const struct bmp280_chip_info bmp280_chip_info = {
586 .oversampling_temp_avail = bmp280_oversampling_avail,
587 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
588
589 .oversampling_press_avail = bmp280_oversampling_avail,
590 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
591
592 .chip_config = bmp280_chip_config,
593 .read_temp = bmp280_read_temp,
594 .read_press = bmp280_read_press,
595 };
596
597 static int bme280_chip_config(struct bmp280_data *data)
598 {
599 int ret = bmp280_chip_config(data);
600 u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
601
602 if (ret < 0)
603 return ret;
604
605 return regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
606 BMP280_OSRS_HUMIDITY_MASK, osrs);
607 }
608
609 static const struct bmp280_chip_info bme280_chip_info = {
610 .oversampling_temp_avail = bmp280_oversampling_avail,
611 .num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
612
613 .oversampling_press_avail = bmp280_oversampling_avail,
614 .num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
615
616 .oversampling_humid_avail = bmp280_oversampling_avail,
617 .num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
618
619 .chip_config = bme280_chip_config,
620 .read_temp = bmp280_read_temp,
621 .read_press = bmp280_read_press,
622 .read_humid = bmp280_read_humid,
623 };
624
625 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
626 {
627 int ret;
628 const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
629 unsigned int delay_us;
630 unsigned int ctrl;
631
632 if (data->use_eoc)
633 init_completion(&data->done);
634
635 ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas);
636 if (ret)
637 return ret;
638
639 if (data->use_eoc) {
640 /*
641 * If we have a completion interrupt, use it, wait up to
642 * 100ms. The longest conversion time listed is 76.5 ms for
643 * advanced resolution mode.
644 */
645 ret = wait_for_completion_timeout(&data->done,
646 1 + msecs_to_jiffies(100));
647 if (!ret)
648 dev_err(data->dev, "timeout waiting for completion\n");
649 } else {
650 if (ctrl_meas == BMP180_MEAS_TEMP)
651 delay_us = 4500;
652 else
653 delay_us =
654 conversion_time_max[data->oversampling_press];
655
656 usleep_range(delay_us, delay_us + 1000);
657 }
658
659 ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl);
660 if (ret)
661 return ret;
662
663 /* The value of this bit reset to "0" after conversion is complete */
664 if (ctrl & BMP180_MEAS_SCO)
665 return -EIO;
666
667 return 0;
668 }
669
670 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
671 {
672 int ret;
673 __be16 tmp = 0;
674
675 ret = bmp180_measure(data, BMP180_MEAS_TEMP);
676 if (ret)
677 return ret;
678
679 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2);
680 if (ret)
681 return ret;
682
683 *val = be16_to_cpu(tmp);
684
685 return 0;
686 }
687
688 static int bmp180_read_calib(struct bmp280_data *data,
689 struct bmp180_calib *calib)
690 {
691 int ret;
692 int i;
693 __be16 buf[BMP180_REG_CALIB_COUNT / 2];
694
695 ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
696 sizeof(buf));
697
698 if (ret < 0)
699 return ret;
700
701 /* None of the words has the value 0 or 0xFFFF */
702 for (i = 0; i < ARRAY_SIZE(buf); i++) {
703 if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff))
704 return -EIO;
705 }
706
707 /* Toss the calibration data into the entropy pool */
708 add_device_randomness(buf, sizeof(buf));
709
710 calib->AC1 = be16_to_cpu(buf[AC1]);
711 calib->AC2 = be16_to_cpu(buf[AC2]);
712 calib->AC3 = be16_to_cpu(buf[AC3]);
713 calib->AC4 = be16_to_cpu(buf[AC4]);
714 calib->AC5 = be16_to_cpu(buf[AC5]);
715 calib->AC6 = be16_to_cpu(buf[AC6]);
716 calib->B1 = be16_to_cpu(buf[B1]);
717 calib->B2 = be16_to_cpu(buf[B2]);
718 calib->MB = be16_to_cpu(buf[MB]);
719 calib->MC = be16_to_cpu(buf[MC]);
720 calib->MD = be16_to_cpu(buf[MD]);
721
722 return 0;
723 }
724
725 /*
726 * Returns temperature in DegC, resolution is 0.1 DegC.
727 * t_fine carries fine temperature as global value.
728 *
729 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
730 */
731 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
732 {
733 s32 x1, x2;
734 struct bmp180_calib *calib = &data->calib;
735
736 x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15;
737 x2 = (calib->MC << 11) / (x1 + calib->MD);
738 data->t_fine = x1 + x2;
739
740 return (data->t_fine + 8) >> 4;
741 }
742
743 static int bmp180_read_temp(struct bmp280_data *data, int *val)
744 {
745 int ret;
746 s32 adc_temp, comp_temp;
747
748 ret = bmp180_read_adc_temp(data, &adc_temp);
749 if (ret)
750 return ret;
751
752 comp_temp = bmp180_compensate_temp(data, adc_temp);
753
754 /*
755 * val might be NULL if we're called by the read_press routine,
756 * who only cares about the carry over t_fine value.
757 */
758 if (val) {
759 *val = comp_temp * 100;
760 return IIO_VAL_INT;
761 }
762
763 return 0;
764 }
765
766 static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
767 {
768 int ret;
769 __be32 tmp = 0;
770 u8 oss = data->oversampling_press;
771
772 ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
773 if (ret)
774 return ret;
775
776 ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3);
777 if (ret)
778 return ret;
779
780 *val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
781
782 return 0;
783 }
784
785 /*
786 * Returns pressure in Pa, resolution is 1 Pa.
787 *
788 * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
789 */
790 static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
791 {
792 s32 x1, x2, x3, p;
793 s32 b3, b6;
794 u32 b4, b7;
795 s32 oss = data->oversampling_press;
796 struct bmp180_calib *calib = &data->calib;
797
798 b6 = data->t_fine - 4000;
799 x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
800 x2 = calib->AC2 * b6 >> 11;
801 x3 = x1 + x2;
802 b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4;
803 x1 = calib->AC3 * b6 >> 13;
804 x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16;
805 x3 = (x1 + x2 + 2) >> 2;
806 b4 = calib->AC4 * (u32)(x3 + 32768) >> 15;
807 b7 = ((u32)adc_press - b3) * (50000 >> oss);
808 if (b7 < 0x80000000)
809 p = (b7 * 2) / b4;
810 else
811 p = (b7 / b4) * 2;
812
813 x1 = (p >> 8) * (p >> 8);
814 x1 = (x1 * 3038) >> 16;
815 x2 = (-7357 * p) >> 16;
816
817 return p + ((x1 + x2 + 3791) >> 4);
818 }
819
820 static int bmp180_read_press(struct bmp280_data *data,
821 int *val, int *val2)
822 {
823 int ret;
824 s32 adc_press;
825 u32 comp_press;
826
827 /* Read and compensate temperature so we get a reading of t_fine. */
828 ret = bmp180_read_temp(data, NULL);
829 if (ret)
830 return ret;
831
832 ret = bmp180_read_adc_press(data, &adc_press);
833 if (ret)
834 return ret;
835
836 comp_press = bmp180_compensate_press(data, adc_press);
837
838 *val = comp_press;
839 *val2 = 1000;
840
841 return IIO_VAL_FRACTIONAL;
842 }
843
844 static int bmp180_chip_config(struct bmp280_data *data)
845 {
846 return 0;
847 }
848
849 static const int bmp180_oversampling_temp_avail[] = { 1 };
850 static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 };
851
852 static const struct bmp280_chip_info bmp180_chip_info = {
853 .oversampling_temp_avail = bmp180_oversampling_temp_avail,
854 .num_oversampling_temp_avail =
855 ARRAY_SIZE(bmp180_oversampling_temp_avail),
856
857 .oversampling_press_avail = bmp180_oversampling_press_avail,
858 .num_oversampling_press_avail =
859 ARRAY_SIZE(bmp180_oversampling_press_avail),
860
861 .chip_config = bmp180_chip_config,
862 .read_temp = bmp180_read_temp,
863 .read_press = bmp180_read_press,
864 };
865
866 static irqreturn_t bmp085_eoc_irq(int irq, void *d)
867 {
868 struct bmp280_data *data = d;
869
870 complete(&data->done);
871
872 return IRQ_HANDLED;
873 }
874
875 static int bmp085_fetch_eoc_irq(struct device *dev,
876 const char *name,
877 int irq,
878 struct bmp280_data *data)
879 {
880 unsigned long irq_trig;
881 int ret;
882
883 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
884 if (irq_trig != IRQF_TRIGGER_RISING) {
885 dev_err(dev, "non-rising trigger given for EOC interrupt, "
886 "trying to enforce it\n");
887 irq_trig = IRQF_TRIGGER_RISING;
888 }
889 ret = devm_request_threaded_irq(dev,
890 irq,
891 bmp085_eoc_irq,
892 NULL,
893 irq_trig,
894 name,
895 data);
896 if (ret) {
897 /* Bail out without IRQ but keep the driver in place */
898 dev_err(dev, "unable to request DRDY IRQ\n");
899 return 0;
900 }
901
902 data->use_eoc = true;
903 return 0;
904 }
905
906 int bmp280_common_probe(struct device *dev,
907 struct regmap *regmap,
908 unsigned int chip,
909 const char *name,
910 int irq)
911 {
912 int ret;
913 struct iio_dev *indio_dev;
914 struct bmp280_data *data;
915 unsigned int chip_id;
916 struct gpio_desc *gpiod;
917
918 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
919 if (!indio_dev)
920 return -ENOMEM;
921
922 data = iio_priv(indio_dev);
923 mutex_init(&data->lock);
924 data->dev = dev;
925
926 indio_dev->dev.parent = dev;
927 indio_dev->name = name;
928 indio_dev->channels = bmp280_channels;
929 indio_dev->info = &bmp280_info;
930 indio_dev->modes = INDIO_DIRECT_MODE;
931
932 switch (chip) {
933 case BMP180_CHIP_ID:
934 indio_dev->num_channels = 2;
935 data->chip_info = &bmp180_chip_info;
936 data->oversampling_press = ilog2(8);
937 data->oversampling_temp = ilog2(1);
938 data->start_up_time = 10;
939 break;
940 case BMP280_CHIP_ID:
941 indio_dev->num_channels = 2;
942 data->chip_info = &bmp280_chip_info;
943 data->oversampling_press = ilog2(16);
944 data->oversampling_temp = ilog2(2);
945 data->start_up_time = 2;
946 break;
947 case BME280_CHIP_ID:
948 indio_dev->num_channels = 3;
949 data->chip_info = &bme280_chip_info;
950 data->oversampling_press = ilog2(16);
951 data->oversampling_humid = ilog2(16);
952 data->oversampling_temp = ilog2(2);
953 data->start_up_time = 2;
954 break;
955 default:
956 return -EINVAL;
957 }
958
959 /* Bring up regulators */
960 data->vddd = devm_regulator_get(dev, "vddd");
961 if (IS_ERR(data->vddd)) {
962 dev_err(dev, "failed to get VDDD regulator\n");
963 return PTR_ERR(data->vddd);
964 }
965 ret = regulator_enable(data->vddd);
966 if (ret) {
967 dev_err(dev, "failed to enable VDDD regulator\n");
968 return ret;
969 }
970 data->vdda = devm_regulator_get(dev, "vdda");
971 if (IS_ERR(data->vdda)) {
972 dev_err(dev, "failed to get VDDA regulator\n");
973 ret = PTR_ERR(data->vdda);
974 goto out_disable_vddd;
975 }
976 ret = regulator_enable(data->vdda);
977 if (ret) {
978 dev_err(dev, "failed to enable VDDA regulator\n");
979 goto out_disable_vddd;
980 }
981 /* Wait to make sure we started up properly */
982 mdelay(data->start_up_time);
983
984 /* Bring chip out of reset if there is an assigned GPIO line */
985 gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
986 /* Deassert the signal */
987 if (!IS_ERR(gpiod)) {
988 dev_info(dev, "release reset\n");
989 gpiod_set_value(gpiod, 0);
990 }
991
992 data->regmap = regmap;
993 ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
994 if (ret < 0)
995 goto out_disable_vdda;
996 if (chip_id != chip) {
997 dev_err(dev, "bad chip id: expected %x got %x\n",
998 chip, chip_id);
999 ret = -EINVAL;
1000 goto out_disable_vdda;
1001 }
1002
1003 ret = data->chip_info->chip_config(data);
1004 if (ret < 0)
1005 goto out_disable_vdda;
1006
1007 dev_set_drvdata(dev, indio_dev);
1008
1009 /*
1010 * The BMP085 and BMP180 has calibration in an E2PROM, read it out
1011 * at probe time. It will not change.
1012 */
1013 if (chip_id == BMP180_CHIP_ID) {
1014 ret = bmp180_read_calib(data, &data->calib);
1015 if (ret < 0) {
1016 dev_err(data->dev,
1017 "failed to read calibration coefficients\n");
1018 goto out_disable_vdda;
1019 }
1020 }
1021
1022 /*
1023 * Attempt to grab an optional EOC IRQ - only the BMP085 has this
1024 * however as it happens, the BMP085 shares the chip ID of BMP180
1025 * so we look for an IRQ if we have that.
1026 */
1027 if (irq > 0 || (chip_id == BMP180_CHIP_ID)) {
1028 ret = bmp085_fetch_eoc_irq(dev, name, irq, data);
1029 if (ret)
1030 goto out_disable_vdda;
1031 }
1032
1033 /* Enable runtime PM */
1034 pm_runtime_get_noresume(dev);
1035 pm_runtime_set_active(dev);
1036 pm_runtime_enable(dev);
1037 /*
1038 * Set autosuspend to two orders of magnitude larger than the
1039 * start-up time.
1040 */
1041 pm_runtime_set_autosuspend_delay(dev, data->start_up_time *100);
1042 pm_runtime_use_autosuspend(dev);
1043 pm_runtime_put(dev);
1044
1045 ret = iio_device_register(indio_dev);
1046 if (ret)
1047 goto out_runtime_pm_disable;
1048
1049
1050 return 0;
1051
1052 out_runtime_pm_disable:
1053 pm_runtime_get_sync(data->dev);
1054 pm_runtime_put_noidle(data->dev);
1055 pm_runtime_disable(data->dev);
1056 out_disable_vdda:
1057 regulator_disable(data->vdda);
1058 out_disable_vddd:
1059 regulator_disable(data->vddd);
1060 return ret;
1061 }
1062 EXPORT_SYMBOL(bmp280_common_probe);
1063
1064 int bmp280_common_remove(struct device *dev)
1065 {
1066 struct iio_dev *indio_dev = dev_get_drvdata(dev);
1067 struct bmp280_data *data = iio_priv(indio_dev);
1068
1069 iio_device_unregister(indio_dev);
1070 pm_runtime_get_sync(data->dev);
1071 pm_runtime_put_noidle(data->dev);
1072 pm_runtime_disable(data->dev);
1073 regulator_disable(data->vdda);
1074 regulator_disable(data->vddd);
1075 return 0;
1076 }
1077 EXPORT_SYMBOL(bmp280_common_remove);
1078
1079 #ifdef CONFIG_PM
1080 static int bmp280_runtime_suspend(struct device *dev)
1081 {
1082 struct iio_dev *indio_dev = dev_get_drvdata(dev);
1083 struct bmp280_data *data = iio_priv(indio_dev);
1084 int ret;
1085
1086 ret = regulator_disable(data->vdda);
1087 if (ret)
1088 return ret;
1089 return regulator_disable(data->vddd);
1090 }
1091
1092 static int bmp280_runtime_resume(struct device *dev)
1093 {
1094 struct iio_dev *indio_dev = dev_get_drvdata(dev);
1095 struct bmp280_data *data = iio_priv(indio_dev);
1096 int ret;
1097
1098 ret = regulator_enable(data->vddd);
1099 if (ret)
1100 return ret;
1101 ret = regulator_enable(data->vdda);
1102 if (ret)
1103 return ret;
1104 msleep(data->start_up_time);
1105 return data->chip_info->chip_config(data);
1106 }
1107 #endif /* CONFIG_PM */
1108
1109 const struct dev_pm_ops bmp280_dev_pm_ops = {
1110 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1111 pm_runtime_force_resume)
1112 SET_RUNTIME_PM_OPS(bmp280_runtime_suspend,
1113 bmp280_runtime_resume, NULL)
1114 };
1115 EXPORT_SYMBOL(bmp280_dev_pm_ops);
1116
1117 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1118 MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
1119 MODULE_LICENSE("GPL v2");
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