Merge tag 'iio-for-5.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio...
[linux-2.6-microblaze.git] / drivers / iio / humidity / hts221_core.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * STMicroelectronics hts221 sensor driver
4  *
5  * Copyright 2016 STMicroelectronics Inc.
6  *
7  * Lorenzo Bianconi <lorenzo.bianconi@st.com>
8  */
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/iio/sysfs.h>
14 #include <linux/delay.h>
15 #include <linux/pm.h>
16 #include <linux/regmap.h>
17 #include <linux/bitfield.h>
18
19 #include "hts221.h"
20
21 #define HTS221_REG_WHOAMI_ADDR          0x0f
22 #define HTS221_REG_WHOAMI_VAL           0xbc
23
24 #define HTS221_REG_CNTRL1_ADDR          0x20
25 #define HTS221_REG_CNTRL2_ADDR          0x21
26
27 #define HTS221_ODR_MASK                 0x03
28 #define HTS221_BDU_MASK                 BIT(2)
29 #define HTS221_ENABLE_MASK              BIT(7)
30
31 /* calibration registers */
32 #define HTS221_REG_0RH_CAL_X_H          0x36
33 #define HTS221_REG_1RH_CAL_X_H          0x3a
34 #define HTS221_REG_0RH_CAL_Y_H          0x30
35 #define HTS221_REG_1RH_CAL_Y_H          0x31
36 #define HTS221_REG_0T_CAL_X_L           0x3c
37 #define HTS221_REG_1T_CAL_X_L           0x3e
38 #define HTS221_REG_0T_CAL_Y_H           0x32
39 #define HTS221_REG_1T_CAL_Y_H           0x33
40 #define HTS221_REG_T1_T0_CAL_Y_H        0x35
41
42 struct hts221_odr {
43         u8 hz;
44         u8 val;
45 };
46
47 #define HTS221_AVG_DEPTH                8
48 struct hts221_avg {
49         u8 addr;
50         u8 mask;
51         u16 avg_avl[HTS221_AVG_DEPTH];
52 };
53
54 static const struct hts221_odr hts221_odr_table[] = {
55         {  1, 0x01 },   /* 1Hz */
56         {  7, 0x02 },   /* 7Hz */
57         { 13, 0x03 },   /* 12.5Hz */
58 };
59
60 static const struct hts221_avg hts221_avg_list[] = {
61         {
62                 .addr = 0x10,
63                 .mask = 0x07,
64                 .avg_avl = {
65                         4, /* 0.4 %RH */
66                         8, /* 0.3 %RH */
67                         16, /* 0.2 %RH */
68                         32, /* 0.15 %RH */
69                         64, /* 0.1 %RH */
70                         128, /* 0.07 %RH */
71                         256, /* 0.05 %RH */
72                         512, /* 0.03 %RH */
73                 },
74         },
75         {
76                 .addr = 0x10,
77                 .mask = 0x38,
78                 .avg_avl = {
79                         2, /* 0.08 degC */
80                         4, /* 0.05 degC */
81                         8, /* 0.04 degC */
82                         16, /* 0.03 degC */
83                         32, /* 0.02 degC */
84                         64, /* 0.015 degC */
85                         128, /* 0.01 degC */
86                         256, /* 0.007 degC */
87                 },
88         },
89 };
90
91 static const struct iio_chan_spec hts221_channels[] = {
92         {
93                 .type = IIO_HUMIDITYRELATIVE,
94                 .address = 0x28,
95                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
96                                       BIT(IIO_CHAN_INFO_OFFSET) |
97                                       BIT(IIO_CHAN_INFO_SCALE) |
98                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
99                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
100                 .scan_index = 0,
101                 .scan_type = {
102                         .sign = 's',
103                         .realbits = 16,
104                         .storagebits = 16,
105                         .endianness = IIO_LE,
106                 },
107         },
108         {
109                 .type = IIO_TEMP,
110                 .address = 0x2a,
111                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
112                                       BIT(IIO_CHAN_INFO_OFFSET) |
113                                       BIT(IIO_CHAN_INFO_SCALE) |
114                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
115                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
116                 .scan_index = 1,
117                 .scan_type = {
118                         .sign = 's',
119                         .realbits = 16,
120                         .storagebits = 16,
121                         .endianness = IIO_LE,
122                 },
123         },
124         IIO_CHAN_SOFT_TIMESTAMP(2),
125 };
126
127 static int hts221_check_whoami(struct hts221_hw *hw)
128 {
129         int err, data;
130
131         err = regmap_read(hw->regmap, HTS221_REG_WHOAMI_ADDR, &data);
132         if (err < 0) {
133                 dev_err(hw->dev, "failed to read whoami register\n");
134                 return err;
135         }
136
137         if (data != HTS221_REG_WHOAMI_VAL) {
138                 dev_err(hw->dev, "wrong whoami {%02x vs %02x}\n",
139                         data, HTS221_REG_WHOAMI_VAL);
140                 return -ENODEV;
141         }
142
143         return 0;
144 }
145
146 static int hts221_update_odr(struct hts221_hw *hw, u8 odr)
147 {
148         int i, err;
149
150         for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
151                 if (hts221_odr_table[i].hz == odr)
152                         break;
153
154         if (i == ARRAY_SIZE(hts221_odr_table))
155                 return -EINVAL;
156
157         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
158                                  HTS221_ODR_MASK,
159                                  FIELD_PREP(HTS221_ODR_MASK,
160                                             hts221_odr_table[i].val));
161         if (err < 0)
162                 return err;
163
164         hw->odr = odr;
165
166         return 0;
167 }
168
169 static int hts221_update_avg(struct hts221_hw *hw,
170                              enum hts221_sensor_type type,
171                              u16 val)
172 {
173         const struct hts221_avg *avg = &hts221_avg_list[type];
174         int i, err, data;
175
176         for (i = 0; i < HTS221_AVG_DEPTH; i++)
177                 if (avg->avg_avl[i] == val)
178                         break;
179
180         if (i == HTS221_AVG_DEPTH)
181                 return -EINVAL;
182
183         data = ((i << __ffs(avg->mask)) & avg->mask);
184         err = regmap_update_bits(hw->regmap, avg->addr,
185                                  avg->mask, data);
186         if (err < 0)
187                 return err;
188
189         hw->sensors[type].cur_avg_idx = i;
190
191         return 0;
192 }
193
194 static ssize_t hts221_sysfs_sampling_freq(struct device *dev,
195                                           struct device_attribute *attr,
196                                           char *buf)
197 {
198         int i;
199         ssize_t len = 0;
200
201         for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
202                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
203                                  hts221_odr_table[i].hz);
204         buf[len - 1] = '\n';
205
206         return len;
207 }
208
209 static ssize_t
210 hts221_sysfs_rh_oversampling_avail(struct device *dev,
211                                    struct device_attribute *attr,
212                                    char *buf)
213 {
214         const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_H];
215         ssize_t len = 0;
216         int i;
217
218         for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
219                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
220                                  avg->avg_avl[i]);
221         buf[len - 1] = '\n';
222
223         return len;
224 }
225
226 static ssize_t
227 hts221_sysfs_temp_oversampling_avail(struct device *dev,
228                                      struct device_attribute *attr,
229                                      char *buf)
230 {
231         const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_T];
232         ssize_t len = 0;
233         int i;
234
235         for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
236                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
237                                  avg->avg_avl[i]);
238         buf[len - 1] = '\n';
239
240         return len;
241 }
242
243 int hts221_set_enable(struct hts221_hw *hw, bool enable)
244 {
245         int err;
246
247         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
248                                  HTS221_ENABLE_MASK,
249                                  FIELD_PREP(HTS221_ENABLE_MASK, enable));
250         if (err < 0)
251                 return err;
252
253         hw->enabled = enable;
254
255         return 0;
256 }
257
258 static int hts221_parse_temp_caldata(struct hts221_hw *hw)
259 {
260         int err, *slope, *b_gen, cal0, cal1;
261         s16 cal_x0, cal_x1, cal_y0, cal_y1;
262         __le16 val;
263
264         err = regmap_read(hw->regmap, HTS221_REG_0T_CAL_Y_H, &cal0);
265         if (err < 0)
266                 return err;
267
268         err = regmap_read(hw->regmap, HTS221_REG_T1_T0_CAL_Y_H, &cal1);
269         if (err < 0)
270                 return err;
271         cal_y0 = ((cal1 & 0x3) << 8) | cal0;
272
273         err = regmap_read(hw->regmap, HTS221_REG_1T_CAL_Y_H, &cal0);
274         if (err < 0)
275                 return err;
276         cal_y1 = (((cal1 & 0xc) >> 2) << 8) | cal0;
277
278         err = regmap_bulk_read(hw->regmap, HTS221_REG_0T_CAL_X_L,
279                                &val, sizeof(val));
280         if (err < 0)
281                 return err;
282         cal_x0 = le16_to_cpu(val);
283
284         err = regmap_bulk_read(hw->regmap, HTS221_REG_1T_CAL_X_L,
285                                &val, sizeof(val));
286         if (err < 0)
287                 return err;
288         cal_x1 = le16_to_cpu(val);
289
290         slope = &hw->sensors[HTS221_SENSOR_T].slope;
291         b_gen = &hw->sensors[HTS221_SENSOR_T].b_gen;
292
293         *slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
294         *b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
295                  (cal_x1 - cal_x0);
296         *b_gen *= 8;
297
298         return 0;
299 }
300
301 static int hts221_parse_rh_caldata(struct hts221_hw *hw)
302 {
303         int err, *slope, *b_gen, data;
304         s16 cal_x0, cal_x1, cal_y0, cal_y1;
305         __le16 val;
306
307         err = regmap_read(hw->regmap, HTS221_REG_0RH_CAL_Y_H, &data);
308         if (err < 0)
309                 return err;
310         cal_y0 = data;
311
312         err = regmap_read(hw->regmap, HTS221_REG_1RH_CAL_Y_H, &data);
313         if (err < 0)
314                 return err;
315         cal_y1 = data;
316
317         err = regmap_bulk_read(hw->regmap, HTS221_REG_0RH_CAL_X_H,
318                                &val, sizeof(val));
319         if (err < 0)
320                 return err;
321         cal_x0 = le16_to_cpu(val);
322
323         err = regmap_bulk_read(hw->regmap, HTS221_REG_1RH_CAL_X_H,
324                                &val, sizeof(val));
325         if (err < 0)
326                 return err;
327         cal_x1 = le16_to_cpu(val);
328
329         slope = &hw->sensors[HTS221_SENSOR_H].slope;
330         b_gen = &hw->sensors[HTS221_SENSOR_H].b_gen;
331
332         *slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
333         *b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
334                  (cal_x1 - cal_x0);
335         *b_gen *= 8;
336
337         return 0;
338 }
339
340 static int hts221_get_sensor_scale(struct hts221_hw *hw,
341                                    enum iio_chan_type ch_type,
342                                    int *val, int *val2)
343 {
344         s64 tmp;
345         s32 rem, div, data;
346
347         switch (ch_type) {
348         case IIO_HUMIDITYRELATIVE:
349                 data = hw->sensors[HTS221_SENSOR_H].slope;
350                 div = (1 << 4) * 1000;
351                 break;
352         case IIO_TEMP:
353                 data = hw->sensors[HTS221_SENSOR_T].slope;
354                 div = (1 << 6) * 1000;
355                 break;
356         default:
357                 return -EINVAL;
358         }
359
360         tmp = div_s64(data * 1000000000LL, div);
361         tmp = div_s64_rem(tmp, 1000000000LL, &rem);
362
363         *val = tmp;
364         *val2 = rem;
365
366         return IIO_VAL_INT_PLUS_NANO;
367 }
368
369 static int hts221_get_sensor_offset(struct hts221_hw *hw,
370                                     enum iio_chan_type ch_type,
371                                     int *val, int *val2)
372 {
373         s64 tmp;
374         s32 rem, div, data;
375
376         switch (ch_type) {
377         case IIO_HUMIDITYRELATIVE:
378                 data = hw->sensors[HTS221_SENSOR_H].b_gen;
379                 div = hw->sensors[HTS221_SENSOR_H].slope;
380                 break;
381         case IIO_TEMP:
382                 data = hw->sensors[HTS221_SENSOR_T].b_gen;
383                 div = hw->sensors[HTS221_SENSOR_T].slope;
384                 break;
385         default:
386                 return -EINVAL;
387         }
388
389         tmp = div_s64(data * 1000000000LL, div);
390         tmp = div_s64_rem(tmp, 1000000000LL, &rem);
391
392         *val = tmp;
393         *val2 = rem;
394
395         return IIO_VAL_INT_PLUS_NANO;
396 }
397
398 static int hts221_read_oneshot(struct hts221_hw *hw, u8 addr, int *val)
399 {
400         __le16 data;
401         int err;
402
403         err = hts221_set_enable(hw, true);
404         if (err < 0)
405                 return err;
406
407         msleep(50);
408
409         err = regmap_bulk_read(hw->regmap, addr, &data, sizeof(data));
410         if (err < 0)
411                 return err;
412
413         hts221_set_enable(hw, false);
414
415         *val = (s16)le16_to_cpu(data);
416
417         return IIO_VAL_INT;
418 }
419
420 static int hts221_read_raw(struct iio_dev *iio_dev,
421                            struct iio_chan_spec const *ch,
422                            int *val, int *val2, long mask)
423 {
424         struct hts221_hw *hw = iio_priv(iio_dev);
425         int ret;
426
427         ret = iio_device_claim_direct_mode(iio_dev);
428         if (ret)
429                 return ret;
430
431         switch (mask) {
432         case IIO_CHAN_INFO_RAW:
433                 ret = hts221_read_oneshot(hw, ch->address, val);
434                 break;
435         case IIO_CHAN_INFO_SCALE:
436                 ret = hts221_get_sensor_scale(hw, ch->type, val, val2);
437                 break;
438         case IIO_CHAN_INFO_OFFSET:
439                 ret = hts221_get_sensor_offset(hw, ch->type, val, val2);
440                 break;
441         case IIO_CHAN_INFO_SAMP_FREQ:
442                 *val = hw->odr;
443                 ret = IIO_VAL_INT;
444                 break;
445         case IIO_CHAN_INFO_OVERSAMPLING_RATIO: {
446                 u8 idx;
447                 const struct hts221_avg *avg;
448
449                 switch (ch->type) {
450                 case IIO_HUMIDITYRELATIVE:
451                         avg = &hts221_avg_list[HTS221_SENSOR_H];
452                         idx = hw->sensors[HTS221_SENSOR_H].cur_avg_idx;
453                         *val = avg->avg_avl[idx];
454                         ret = IIO_VAL_INT;
455                         break;
456                 case IIO_TEMP:
457                         avg = &hts221_avg_list[HTS221_SENSOR_T];
458                         idx = hw->sensors[HTS221_SENSOR_T].cur_avg_idx;
459                         *val = avg->avg_avl[idx];
460                         ret = IIO_VAL_INT;
461                         break;
462                 default:
463                         ret = -EINVAL;
464                         break;
465                 }
466                 break;
467         }
468         default:
469                 ret = -EINVAL;
470                 break;
471         }
472
473         iio_device_release_direct_mode(iio_dev);
474
475         return ret;
476 }
477
478 static int hts221_write_raw(struct iio_dev *iio_dev,
479                             struct iio_chan_spec const *chan,
480                             int val, int val2, long mask)
481 {
482         struct hts221_hw *hw = iio_priv(iio_dev);
483         int ret;
484
485         ret = iio_device_claim_direct_mode(iio_dev);
486         if (ret)
487                 return ret;
488
489         switch (mask) {
490         case IIO_CHAN_INFO_SAMP_FREQ:
491                 ret = hts221_update_odr(hw, val);
492                 break;
493         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
494                 switch (chan->type) {
495                 case IIO_HUMIDITYRELATIVE:
496                         ret = hts221_update_avg(hw, HTS221_SENSOR_H, val);
497                         break;
498                 case IIO_TEMP:
499                         ret = hts221_update_avg(hw, HTS221_SENSOR_T, val);
500                         break;
501                 default:
502                         ret = -EINVAL;
503                         break;
504                 }
505                 break;
506         default:
507                 ret = -EINVAL;
508                 break;
509         }
510
511         iio_device_release_direct_mode(iio_dev);
512
513         return ret;
514 }
515
516 static int hts221_validate_trigger(struct iio_dev *iio_dev,
517                                    struct iio_trigger *trig)
518 {
519         struct hts221_hw *hw = iio_priv(iio_dev);
520
521         return hw->trig == trig ? 0 : -EINVAL;
522 }
523
524 static IIO_DEVICE_ATTR(in_humidity_oversampling_ratio_available, S_IRUGO,
525                        hts221_sysfs_rh_oversampling_avail, NULL, 0);
526 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, S_IRUGO,
527                        hts221_sysfs_temp_oversampling_avail, NULL, 0);
528 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hts221_sysfs_sampling_freq);
529
530 static struct attribute *hts221_attributes[] = {
531         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
532         &iio_dev_attr_in_humidity_oversampling_ratio_available.dev_attr.attr,
533         &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
534         NULL,
535 };
536
537 static const struct attribute_group hts221_attribute_group = {
538         .attrs = hts221_attributes,
539 };
540
541 static const struct iio_info hts221_info = {
542         .attrs = &hts221_attribute_group,
543         .read_raw = hts221_read_raw,
544         .write_raw = hts221_write_raw,
545         .validate_trigger = hts221_validate_trigger,
546 };
547
548 static const unsigned long hts221_scan_masks[] = {0x3, 0x0};
549
550 int hts221_probe(struct device *dev, int irq, const char *name,
551                  struct regmap *regmap)
552 {
553         struct iio_dev *iio_dev;
554         struct hts221_hw *hw;
555         int err;
556         u8 data;
557
558         iio_dev = devm_iio_device_alloc(dev, sizeof(*hw));
559         if (!iio_dev)
560                 return -ENOMEM;
561
562         dev_set_drvdata(dev, (void *)iio_dev);
563
564         hw = iio_priv(iio_dev);
565         hw->name = name;
566         hw->dev = dev;
567         hw->irq = irq;
568         hw->regmap = regmap;
569
570         err = hts221_check_whoami(hw);
571         if (err < 0)
572                 return err;
573
574         iio_dev->modes = INDIO_DIRECT_MODE;
575         iio_dev->dev.parent = hw->dev;
576         iio_dev->available_scan_masks = hts221_scan_masks;
577         iio_dev->channels = hts221_channels;
578         iio_dev->num_channels = ARRAY_SIZE(hts221_channels);
579         iio_dev->name = HTS221_DEV_NAME;
580         iio_dev->info = &hts221_info;
581
582         /* enable Block Data Update */
583         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
584                                  HTS221_BDU_MASK,
585                                  FIELD_PREP(HTS221_BDU_MASK, 1));
586         if (err < 0)
587                 return err;
588
589         err = hts221_update_odr(hw, hts221_odr_table[0].hz);
590         if (err < 0)
591                 return err;
592
593         /* configure humidity sensor */
594         err = hts221_parse_rh_caldata(hw);
595         if (err < 0) {
596                 dev_err(hw->dev, "failed to get rh calibration data\n");
597                 return err;
598         }
599
600         data = hts221_avg_list[HTS221_SENSOR_H].avg_avl[3];
601         err = hts221_update_avg(hw, HTS221_SENSOR_H, data);
602         if (err < 0) {
603                 dev_err(hw->dev, "failed to set rh oversampling ratio\n");
604                 return err;
605         }
606
607         /* configure temperature sensor */
608         err = hts221_parse_temp_caldata(hw);
609         if (err < 0) {
610                 dev_err(hw->dev,
611                         "failed to get temperature calibration data\n");
612                 return err;
613         }
614
615         data = hts221_avg_list[HTS221_SENSOR_T].avg_avl[3];
616         err = hts221_update_avg(hw, HTS221_SENSOR_T, data);
617         if (err < 0) {
618                 dev_err(hw->dev,
619                         "failed to set temperature oversampling ratio\n");
620                 return err;
621         }
622
623         if (hw->irq > 0) {
624                 err = hts221_allocate_buffers(hw);
625                 if (err < 0)
626                         return err;
627
628                 err = hts221_allocate_trigger(hw);
629                 if (err)
630                         return err;
631         }
632
633         return devm_iio_device_register(hw->dev, iio_dev);
634 }
635 EXPORT_SYMBOL(hts221_probe);
636
637 static int __maybe_unused hts221_suspend(struct device *dev)
638 {
639         struct iio_dev *iio_dev = dev_get_drvdata(dev);
640         struct hts221_hw *hw = iio_priv(iio_dev);
641
642         return regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
643                                   HTS221_ENABLE_MASK,
644                                   FIELD_PREP(HTS221_ENABLE_MASK, false));
645 }
646
647 static int __maybe_unused hts221_resume(struct device *dev)
648 {
649         struct iio_dev *iio_dev = dev_get_drvdata(dev);
650         struct hts221_hw *hw = iio_priv(iio_dev);
651         int err = 0;
652
653         if (hw->enabled)
654                 err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
655                                          HTS221_ENABLE_MASK,
656                                          FIELD_PREP(HTS221_ENABLE_MASK,
657                                                     true));
658         return err;
659 }
660
661 const struct dev_pm_ops hts221_pm_ops = {
662         SET_SYSTEM_SLEEP_PM_OPS(hts221_suspend, hts221_resume)
663 };
664 EXPORT_SYMBOL(hts221_pm_ops);
665
666 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
667 MODULE_DESCRIPTION("STMicroelectronics hts221 sensor driver");
668 MODULE_LICENSE("GPL v2");