GNU Linux-libre 4.19.264-gnu1
[releases.git] / drivers / iio / humidity / hts221_core.c
1 /*
2  * STMicroelectronics hts221 sensor driver
3  *
4  * Copyright 2016 STMicroelectronics Inc.
5  *
6  * Lorenzo Bianconi <lorenzo.bianconi@st.com>
7  *
8  * Licensed under the GPL-2.
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/iio/sysfs.h>
15 #include <linux/delay.h>
16 #include <linux/pm.h>
17 #include <linux/regmap.h>
18 #include <linux/bitfield.h>
19
20 #include "hts221.h"
21
22 #define HTS221_REG_WHOAMI_ADDR          0x0f
23 #define HTS221_REG_WHOAMI_VAL           0xbc
24
25 #define HTS221_REG_CNTRL1_ADDR          0x20
26 #define HTS221_REG_CNTRL2_ADDR          0x21
27
28 #define HTS221_REG_AVG_ADDR             0x10
29 #define HTS221_REG_H_OUT_L              0x28
30 #define HTS221_REG_T_OUT_L              0x2a
31
32 #define HTS221_HUMIDITY_AVG_MASK        0x07
33 #define HTS221_TEMP_AVG_MASK            0x38
34
35 #define HTS221_ODR_MASK                 0x03
36 #define HTS221_BDU_MASK                 BIT(2)
37 #define HTS221_ENABLE_MASK              BIT(7)
38
39 /* calibration registers */
40 #define HTS221_REG_0RH_CAL_X_H          0x36
41 #define HTS221_REG_1RH_CAL_X_H          0x3a
42 #define HTS221_REG_0RH_CAL_Y_H          0x30
43 #define HTS221_REG_1RH_CAL_Y_H          0x31
44 #define HTS221_REG_0T_CAL_X_L           0x3c
45 #define HTS221_REG_1T_CAL_X_L           0x3e
46 #define HTS221_REG_0T_CAL_Y_H           0x32
47 #define HTS221_REG_1T_CAL_Y_H           0x33
48 #define HTS221_REG_T1_T0_CAL_Y_H        0x35
49
50 struct hts221_odr {
51         u8 hz;
52         u8 val;
53 };
54
55 #define HTS221_AVG_DEPTH                8
56 struct hts221_avg {
57         u8 addr;
58         u8 mask;
59         u16 avg_avl[HTS221_AVG_DEPTH];
60 };
61
62 static const struct hts221_odr hts221_odr_table[] = {
63         {  1, 0x01 },   /* 1Hz */
64         {  7, 0x02 },   /* 7Hz */
65         { 13, 0x03 },   /* 12.5Hz */
66 };
67
68 static const struct hts221_avg hts221_avg_list[] = {
69         {
70                 .addr = HTS221_REG_AVG_ADDR,
71                 .mask = HTS221_HUMIDITY_AVG_MASK,
72                 .avg_avl = {
73                         4, /* 0.4 %RH */
74                         8, /* 0.3 %RH */
75                         16, /* 0.2 %RH */
76                         32, /* 0.15 %RH */
77                         64, /* 0.1 %RH */
78                         128, /* 0.07 %RH */
79                         256, /* 0.05 %RH */
80                         512, /* 0.03 %RH */
81                 },
82         },
83         {
84                 .addr = HTS221_REG_AVG_ADDR,
85                 .mask = HTS221_TEMP_AVG_MASK,
86                 .avg_avl = {
87                         2, /* 0.08 degC */
88                         4, /* 0.05 degC */
89                         8, /* 0.04 degC */
90                         16, /* 0.03 degC */
91                         32, /* 0.02 degC */
92                         64, /* 0.015 degC */
93                         128, /* 0.01 degC */
94                         256, /* 0.007 degC */
95                 },
96         },
97 };
98
99 static const struct iio_chan_spec hts221_channels[] = {
100         {
101                 .type = IIO_HUMIDITYRELATIVE,
102                 .address = HTS221_REG_H_OUT_L,
103                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
104                                       BIT(IIO_CHAN_INFO_OFFSET) |
105                                       BIT(IIO_CHAN_INFO_SCALE) |
106                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
107                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
108                 .scan_index = 0,
109                 .scan_type = {
110                         .sign = 's',
111                         .realbits = 16,
112                         .storagebits = 16,
113                         .endianness = IIO_LE,
114                 },
115         },
116         {
117                 .type = IIO_TEMP,
118                 .address = HTS221_REG_T_OUT_L,
119                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
120                                       BIT(IIO_CHAN_INFO_OFFSET) |
121                                       BIT(IIO_CHAN_INFO_SCALE) |
122                                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
123                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
124                 .scan_index = 1,
125                 .scan_type = {
126                         .sign = 's',
127                         .realbits = 16,
128                         .storagebits = 16,
129                         .endianness = IIO_LE,
130                 },
131         },
132         IIO_CHAN_SOFT_TIMESTAMP(2),
133 };
134
135 static int hts221_check_whoami(struct hts221_hw *hw)
136 {
137         int err, data;
138
139         err = regmap_read(hw->regmap, HTS221_REG_WHOAMI_ADDR, &data);
140         if (err < 0) {
141                 dev_err(hw->dev, "failed to read whoami register\n");
142                 return err;
143         }
144
145         if (data != HTS221_REG_WHOAMI_VAL) {
146                 dev_err(hw->dev, "wrong whoami {%02x vs %02x}\n",
147                         data, HTS221_REG_WHOAMI_VAL);
148                 return -ENODEV;
149         }
150
151         return 0;
152 }
153
154 static int hts221_update_odr(struct hts221_hw *hw, u8 odr)
155 {
156         int i, err;
157
158         for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
159                 if (hts221_odr_table[i].hz == odr)
160                         break;
161
162         if (i == ARRAY_SIZE(hts221_odr_table))
163                 return -EINVAL;
164
165         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
166                                  HTS221_ODR_MASK,
167                                  FIELD_PREP(HTS221_ODR_MASK,
168                                             hts221_odr_table[i].val));
169         if (err < 0)
170                 return err;
171
172         hw->odr = odr;
173
174         return 0;
175 }
176
177 static int hts221_update_avg(struct hts221_hw *hw,
178                              enum hts221_sensor_type type,
179                              u16 val)
180 {
181         const struct hts221_avg *avg = &hts221_avg_list[type];
182         int i, err, data;
183
184         for (i = 0; i < HTS221_AVG_DEPTH; i++)
185                 if (avg->avg_avl[i] == val)
186                         break;
187
188         if (i == HTS221_AVG_DEPTH)
189                 return -EINVAL;
190
191         data = ((i << __ffs(avg->mask)) & avg->mask);
192         err = regmap_update_bits(hw->regmap, avg->addr,
193                                  avg->mask, data);
194         if (err < 0)
195                 return err;
196
197         hw->sensors[type].cur_avg_idx = i;
198
199         return 0;
200 }
201
202 static ssize_t hts221_sysfs_sampling_freq(struct device *dev,
203                                           struct device_attribute *attr,
204                                           char *buf)
205 {
206         int i;
207         ssize_t len = 0;
208
209         for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
210                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
211                                  hts221_odr_table[i].hz);
212         buf[len - 1] = '\n';
213
214         return len;
215 }
216
217 static ssize_t
218 hts221_sysfs_rh_oversampling_avail(struct device *dev,
219                                    struct device_attribute *attr,
220                                    char *buf)
221 {
222         const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_H];
223         ssize_t len = 0;
224         int i;
225
226         for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
227                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
228                                  avg->avg_avl[i]);
229         buf[len - 1] = '\n';
230
231         return len;
232 }
233
234 static ssize_t
235 hts221_sysfs_temp_oversampling_avail(struct device *dev,
236                                      struct device_attribute *attr,
237                                      char *buf)
238 {
239         const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_T];
240         ssize_t len = 0;
241         int i;
242
243         for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
244                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
245                                  avg->avg_avl[i]);
246         buf[len - 1] = '\n';
247
248         return len;
249 }
250
251 int hts221_set_enable(struct hts221_hw *hw, bool enable)
252 {
253         int err;
254
255         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
256                                  HTS221_ENABLE_MASK,
257                                  FIELD_PREP(HTS221_ENABLE_MASK, enable));
258         if (err < 0)
259                 return err;
260
261         hw->enabled = enable;
262
263         return 0;
264 }
265
266 static int hts221_parse_temp_caldata(struct hts221_hw *hw)
267 {
268         int err, *slope, *b_gen, cal0, cal1;
269         s16 cal_x0, cal_x1, cal_y0, cal_y1;
270         __le16 val;
271
272         err = regmap_read(hw->regmap, HTS221_REG_0T_CAL_Y_H, &cal0);
273         if (err < 0)
274                 return err;
275
276         err = regmap_read(hw->regmap, HTS221_REG_T1_T0_CAL_Y_H, &cal1);
277         if (err < 0)
278                 return err;
279         cal_y0 = ((cal1 & 0x3) << 8) | cal0;
280
281         err = regmap_read(hw->regmap, HTS221_REG_1T_CAL_Y_H, &cal0);
282         if (err < 0)
283                 return err;
284         cal_y1 = (((cal1 & 0xc) >> 2) << 8) | cal0;
285
286         err = regmap_bulk_read(hw->regmap, HTS221_REG_0T_CAL_X_L,
287                                &val, sizeof(val));
288         if (err < 0)
289                 return err;
290         cal_x0 = le16_to_cpu(val);
291
292         err = regmap_bulk_read(hw->regmap, HTS221_REG_1T_CAL_X_L,
293                                &val, sizeof(val));
294         if (err < 0)
295                 return err;
296         cal_x1 = le16_to_cpu(val);
297
298         slope = &hw->sensors[HTS221_SENSOR_T].slope;
299         b_gen = &hw->sensors[HTS221_SENSOR_T].b_gen;
300
301         *slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
302         *b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
303                  (cal_x1 - cal_x0);
304         *b_gen *= 8;
305
306         return 0;
307 }
308
309 static int hts221_parse_rh_caldata(struct hts221_hw *hw)
310 {
311         int err, *slope, *b_gen, data;
312         s16 cal_x0, cal_x1, cal_y0, cal_y1;
313         __le16 val;
314
315         err = regmap_read(hw->regmap, HTS221_REG_0RH_CAL_Y_H, &data);
316         if (err < 0)
317                 return err;
318         cal_y0 = data;
319
320         err = regmap_read(hw->regmap, HTS221_REG_1RH_CAL_Y_H, &data);
321         if (err < 0)
322                 return err;
323         cal_y1 = data;
324
325         err = regmap_bulk_read(hw->regmap, HTS221_REG_0RH_CAL_X_H,
326                                &val, sizeof(val));
327         if (err < 0)
328                 return err;
329         cal_x0 = le16_to_cpu(val);
330
331         err = regmap_bulk_read(hw->regmap, HTS221_REG_1RH_CAL_X_H,
332                                &val, sizeof(val));
333         if (err < 0)
334                 return err;
335         cal_x1 = le16_to_cpu(val);
336
337         slope = &hw->sensors[HTS221_SENSOR_H].slope;
338         b_gen = &hw->sensors[HTS221_SENSOR_H].b_gen;
339
340         *slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
341         *b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
342                  (cal_x1 - cal_x0);
343         *b_gen *= 8;
344
345         return 0;
346 }
347
348 static int hts221_get_sensor_scale(struct hts221_hw *hw,
349                                    enum iio_chan_type ch_type,
350                                    int *val, int *val2)
351 {
352         s64 tmp;
353         s32 rem, div, data;
354
355         switch (ch_type) {
356         case IIO_HUMIDITYRELATIVE:
357                 data = hw->sensors[HTS221_SENSOR_H].slope;
358                 div = (1 << 4) * 1000;
359                 break;
360         case IIO_TEMP:
361                 data = hw->sensors[HTS221_SENSOR_T].slope;
362                 div = (1 << 6) * 1000;
363                 break;
364         default:
365                 return -EINVAL;
366         }
367
368         tmp = div_s64(data * 1000000000LL, div);
369         tmp = div_s64_rem(tmp, 1000000000LL, &rem);
370
371         *val = tmp;
372         *val2 = rem;
373
374         return IIO_VAL_INT_PLUS_NANO;
375 }
376
377 static int hts221_get_sensor_offset(struct hts221_hw *hw,
378                                     enum iio_chan_type ch_type,
379                                     int *val, int *val2)
380 {
381         s64 tmp;
382         s32 rem, div, data;
383
384         switch (ch_type) {
385         case IIO_HUMIDITYRELATIVE:
386                 data = hw->sensors[HTS221_SENSOR_H].b_gen;
387                 div = hw->sensors[HTS221_SENSOR_H].slope;
388                 break;
389         case IIO_TEMP:
390                 data = hw->sensors[HTS221_SENSOR_T].b_gen;
391                 div = hw->sensors[HTS221_SENSOR_T].slope;
392                 break;
393         default:
394                 return -EINVAL;
395         }
396
397         tmp = div_s64(data * 1000000000LL, div);
398         tmp = div_s64_rem(tmp, 1000000000LL, &rem);
399
400         *val = tmp;
401         *val2 = rem;
402
403         return IIO_VAL_INT_PLUS_NANO;
404 }
405
406 static int hts221_read_oneshot(struct hts221_hw *hw, u8 addr, int *val)
407 {
408         __le16 data;
409         int err;
410
411         err = hts221_set_enable(hw, true);
412         if (err < 0)
413                 return err;
414
415         msleep(50);
416
417         err = regmap_bulk_read(hw->regmap, addr, &data, sizeof(data));
418         if (err < 0)
419                 return err;
420
421         hts221_set_enable(hw, false);
422
423         *val = (s16)le16_to_cpu(data);
424
425         return IIO_VAL_INT;
426 }
427
428 static int hts221_read_raw(struct iio_dev *iio_dev,
429                            struct iio_chan_spec const *ch,
430                            int *val, int *val2, long mask)
431 {
432         struct hts221_hw *hw = iio_priv(iio_dev);
433         int ret;
434
435         ret = iio_device_claim_direct_mode(iio_dev);
436         if (ret)
437                 return ret;
438
439         switch (mask) {
440         case IIO_CHAN_INFO_RAW:
441                 ret = hts221_read_oneshot(hw, ch->address, val);
442                 break;
443         case IIO_CHAN_INFO_SCALE:
444                 ret = hts221_get_sensor_scale(hw, ch->type, val, val2);
445                 break;
446         case IIO_CHAN_INFO_OFFSET:
447                 ret = hts221_get_sensor_offset(hw, ch->type, val, val2);
448                 break;
449         case IIO_CHAN_INFO_SAMP_FREQ:
450                 *val = hw->odr;
451                 ret = IIO_VAL_INT;
452                 break;
453         case IIO_CHAN_INFO_OVERSAMPLING_RATIO: {
454                 u8 idx;
455                 const struct hts221_avg *avg;
456
457                 switch (ch->type) {
458                 case IIO_HUMIDITYRELATIVE:
459                         avg = &hts221_avg_list[HTS221_SENSOR_H];
460                         idx = hw->sensors[HTS221_SENSOR_H].cur_avg_idx;
461                         *val = avg->avg_avl[idx];
462                         ret = IIO_VAL_INT;
463                         break;
464                 case IIO_TEMP:
465                         avg = &hts221_avg_list[HTS221_SENSOR_T];
466                         idx = hw->sensors[HTS221_SENSOR_T].cur_avg_idx;
467                         *val = avg->avg_avl[idx];
468                         ret = IIO_VAL_INT;
469                         break;
470                 default:
471                         ret = -EINVAL;
472                         break;
473                 }
474                 break;
475         }
476         default:
477                 ret = -EINVAL;
478                 break;
479         }
480
481         iio_device_release_direct_mode(iio_dev);
482
483         return ret;
484 }
485
486 static int hts221_write_raw(struct iio_dev *iio_dev,
487                             struct iio_chan_spec const *chan,
488                             int val, int val2, long mask)
489 {
490         struct hts221_hw *hw = iio_priv(iio_dev);
491         int ret;
492
493         ret = iio_device_claim_direct_mode(iio_dev);
494         if (ret)
495                 return ret;
496
497         switch (mask) {
498         case IIO_CHAN_INFO_SAMP_FREQ:
499                 ret = hts221_update_odr(hw, val);
500                 break;
501         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
502                 switch (chan->type) {
503                 case IIO_HUMIDITYRELATIVE:
504                         ret = hts221_update_avg(hw, HTS221_SENSOR_H, val);
505                         break;
506                 case IIO_TEMP:
507                         ret = hts221_update_avg(hw, HTS221_SENSOR_T, val);
508                         break;
509                 default:
510                         ret = -EINVAL;
511                         break;
512                 }
513                 break;
514         default:
515                 ret = -EINVAL;
516                 break;
517         }
518
519         iio_device_release_direct_mode(iio_dev);
520
521         return ret;
522 }
523
524 static int hts221_validate_trigger(struct iio_dev *iio_dev,
525                                    struct iio_trigger *trig)
526 {
527         struct hts221_hw *hw = iio_priv(iio_dev);
528
529         return hw->trig == trig ? 0 : -EINVAL;
530 }
531
532 static IIO_DEVICE_ATTR(in_humidity_oversampling_ratio_available, S_IRUGO,
533                        hts221_sysfs_rh_oversampling_avail, NULL, 0);
534 static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, S_IRUGO,
535                        hts221_sysfs_temp_oversampling_avail, NULL, 0);
536 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hts221_sysfs_sampling_freq);
537
538 static struct attribute *hts221_attributes[] = {
539         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
540         &iio_dev_attr_in_humidity_oversampling_ratio_available.dev_attr.attr,
541         &iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
542         NULL,
543 };
544
545 static const struct attribute_group hts221_attribute_group = {
546         .attrs = hts221_attributes,
547 };
548
549 static const struct iio_info hts221_info = {
550         .attrs = &hts221_attribute_group,
551         .read_raw = hts221_read_raw,
552         .write_raw = hts221_write_raw,
553         .validate_trigger = hts221_validate_trigger,
554 };
555
556 static const unsigned long hts221_scan_masks[] = {0x3, 0x0};
557
558 int hts221_probe(struct device *dev, int irq, const char *name,
559                  struct regmap *regmap)
560 {
561         struct iio_dev *iio_dev;
562         struct hts221_hw *hw;
563         int err;
564         u8 data;
565
566         iio_dev = devm_iio_device_alloc(dev, sizeof(*hw));
567         if (!iio_dev)
568                 return -ENOMEM;
569
570         dev_set_drvdata(dev, (void *)iio_dev);
571
572         hw = iio_priv(iio_dev);
573         hw->name = name;
574         hw->dev = dev;
575         hw->irq = irq;
576         hw->regmap = regmap;
577
578         err = hts221_check_whoami(hw);
579         if (err < 0)
580                 return err;
581
582         iio_dev->modes = INDIO_DIRECT_MODE;
583         iio_dev->dev.parent = hw->dev;
584         iio_dev->available_scan_masks = hts221_scan_masks;
585         iio_dev->channels = hts221_channels;
586         iio_dev->num_channels = ARRAY_SIZE(hts221_channels);
587         iio_dev->name = HTS221_DEV_NAME;
588         iio_dev->info = &hts221_info;
589
590         /* enable Block Data Update */
591         err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
592                                  HTS221_BDU_MASK,
593                                  FIELD_PREP(HTS221_BDU_MASK, 1));
594         if (err < 0)
595                 return err;
596
597         err = hts221_update_odr(hw, hts221_odr_table[0].hz);
598         if (err < 0)
599                 return err;
600
601         /* configure humidity sensor */
602         err = hts221_parse_rh_caldata(hw);
603         if (err < 0) {
604                 dev_err(hw->dev, "failed to get rh calibration data\n");
605                 return err;
606         }
607
608         data = hts221_avg_list[HTS221_SENSOR_H].avg_avl[3];
609         err = hts221_update_avg(hw, HTS221_SENSOR_H, data);
610         if (err < 0) {
611                 dev_err(hw->dev, "failed to set rh oversampling ratio\n");
612                 return err;
613         }
614
615         /* configure temperature sensor */
616         err = hts221_parse_temp_caldata(hw);
617         if (err < 0) {
618                 dev_err(hw->dev,
619                         "failed to get temperature calibration data\n");
620                 return err;
621         }
622
623         data = hts221_avg_list[HTS221_SENSOR_T].avg_avl[3];
624         err = hts221_update_avg(hw, HTS221_SENSOR_T, data);
625         if (err < 0) {
626                 dev_err(hw->dev,
627                         "failed to set temperature oversampling ratio\n");
628                 return err;
629         }
630
631         if (hw->irq > 0) {
632                 err = hts221_allocate_buffers(hw);
633                 if (err < 0)
634                         return err;
635
636                 err = hts221_allocate_trigger(hw);
637                 if (err)
638                         return err;
639         }
640
641         return devm_iio_device_register(hw->dev, iio_dev);
642 }
643 EXPORT_SYMBOL(hts221_probe);
644
645 static int __maybe_unused hts221_suspend(struct device *dev)
646 {
647         struct iio_dev *iio_dev = dev_get_drvdata(dev);
648         struct hts221_hw *hw = iio_priv(iio_dev);
649
650         return regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
651                                   HTS221_ENABLE_MASK,
652                                   FIELD_PREP(HTS221_ENABLE_MASK, false));
653 }
654
655 static int __maybe_unused hts221_resume(struct device *dev)
656 {
657         struct iio_dev *iio_dev = dev_get_drvdata(dev);
658         struct hts221_hw *hw = iio_priv(iio_dev);
659         int err = 0;
660
661         if (hw->enabled)
662                 err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
663                                          HTS221_ENABLE_MASK,
664                                          FIELD_PREP(HTS221_ENABLE_MASK,
665                                                     true));
666         return err;
667 }
668
669 const struct dev_pm_ops hts221_pm_ops = {
670         SET_SYSTEM_SLEEP_PM_OPS(hts221_suspend, hts221_resume)
671 };
672 EXPORT_SYMBOL(hts221_pm_ops);
673
674 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
675 MODULE_DESCRIPTION("STMicroelectronics hts221 sensor driver");
676 MODULE_LICENSE("GPL v2");