Merge tag 'fsnotify_for_v6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / drivers / iio / pressure / icp10100.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2020 InvenSense, Inc.
4  *
5  * Driver for InvenSense ICP-1010xx barometric pressure and temperature sensor.
6  *
7  * Datasheet:
8  * http://www.invensense.com/wp-content/uploads/2018/01/DS-000186-ICP-101xx-v1.2.pdf
9  */
10
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/i2c.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/crc8.h>
17 #include <linux/mutex.h>
18 #include <linux/delay.h>
19 #include <linux/log2.h>
20 #include <linux/math64.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/iio/iio.h>
23
24 #define ICP10100_ID_REG_GET(_reg)       ((_reg) & 0x003F)
25 #define ICP10100_ID_REG                 0x08
26 #define ICP10100_RESPONSE_WORD_LENGTH   3
27 #define ICP10100_CRC8_WORD_LENGTH       2
28 #define ICP10100_CRC8_POLYNOMIAL        0x31
29 #define ICP10100_CRC8_INIT              0xFF
30
31 enum icp10100_mode {
32         ICP10100_MODE_LP,       /* Low power mode: 1x sampling */
33         ICP10100_MODE_N,        /* Normal mode: 2x sampling */
34         ICP10100_MODE_LN,       /* Low noise mode: 4x sampling */
35         ICP10100_MODE_ULN,      /* Ultra low noise mode: 8x sampling */
36         ICP10100_MODE_NB,
37 };
38
39 struct icp10100_state {
40         struct mutex lock;
41         struct i2c_client *client;
42         struct regulator *vdd;
43         enum icp10100_mode mode;
44         int16_t cal[4];
45 };
46
47 struct icp10100_command {
48         __be16 cmd;
49         unsigned long wait_us;
50         unsigned long wait_max_us;
51         size_t response_word_nb;
52 };
53
54 static const struct icp10100_command icp10100_cmd_soft_reset = {
55         .cmd = cpu_to_be16(0x805D),
56         .wait_us = 170,
57         .wait_max_us = 200,
58         .response_word_nb = 0,
59 };
60
61 static const struct icp10100_command icp10100_cmd_read_id = {
62         .cmd = cpu_to_be16(0xEFC8),
63         .wait_us = 0,
64         .response_word_nb = 1,
65 };
66
67 static const struct icp10100_command icp10100_cmd_read_otp = {
68         .cmd = cpu_to_be16(0xC7F7),
69         .wait_us = 0,
70         .response_word_nb = 1,
71 };
72
73 static const struct icp10100_command icp10100_cmd_measure[] = {
74         [ICP10100_MODE_LP] = {
75                 .cmd = cpu_to_be16(0x401A),
76                 .wait_us = 1800,
77                 .wait_max_us = 2000,
78                 .response_word_nb = 3,
79         },
80         [ICP10100_MODE_N] = {
81                 .cmd = cpu_to_be16(0x48A3),
82                 .wait_us = 6300,
83                 .wait_max_us = 6500,
84                 .response_word_nb = 3,
85         },
86         [ICP10100_MODE_LN] = {
87                 .cmd = cpu_to_be16(0x5059),
88                 .wait_us = 23800,
89                 .wait_max_us = 24000,
90                 .response_word_nb = 3,
91         },
92         [ICP10100_MODE_ULN] = {
93                 .cmd = cpu_to_be16(0x58E0),
94                 .wait_us = 94500,
95                 .wait_max_us = 94700,
96                 .response_word_nb = 3,
97         },
98 };
99
100 static const uint8_t icp10100_switch_mode_otp[] =
101         {0xC5, 0x95, 0x00, 0x66, 0x9c};
102
103 DECLARE_CRC8_TABLE(icp10100_crc8_table);
104
105 static inline int icp10100_i2c_xfer(struct i2c_adapter *adap,
106                                     struct i2c_msg *msgs, int num)
107 {
108         int ret;
109
110         ret = i2c_transfer(adap, msgs, num);
111         if (ret < 0)
112                 return ret;
113
114         if (ret != num)
115                 return -EIO;
116
117         return 0;
118 }
119
120 static int icp10100_send_cmd(struct icp10100_state *st,
121                              const struct icp10100_command *cmd,
122                              __be16 *buf, size_t buf_len)
123 {
124         size_t size = cmd->response_word_nb * ICP10100_RESPONSE_WORD_LENGTH;
125         uint8_t data[16];
126         uint8_t *ptr;
127         uint8_t *buf_ptr = (uint8_t *)buf;
128         struct i2c_msg msgs[2] = {
129                 {
130                         .addr = st->client->addr,
131                         .flags = 0,
132                         .len = 2,
133                         .buf = (uint8_t *)&cmd->cmd,
134                 }, {
135                         .addr = st->client->addr,
136                         .flags = I2C_M_RD,
137                         .len = size,
138                         .buf = data,
139                 },
140         };
141         uint8_t crc;
142         unsigned int i;
143         int ret;
144
145         if (size > sizeof(data))
146                 return -EINVAL;
147
148         if (cmd->response_word_nb > 0 &&
149                         (buf == NULL || buf_len < (cmd->response_word_nb * 2)))
150                 return -EINVAL;
151
152         dev_dbg(&st->client->dev, "sending cmd %#x\n", be16_to_cpu(cmd->cmd));
153
154         if (cmd->response_word_nb > 0 && cmd->wait_us == 0) {
155                 /* direct command-response without waiting */
156                 ret = icp10100_i2c_xfer(st->client->adapter, msgs,
157                                         ARRAY_SIZE(msgs));
158                 if (ret)
159                         return ret;
160         } else {
161                 /* transfer command write */
162                 ret = icp10100_i2c_xfer(st->client->adapter, &msgs[0], 1);
163                 if (ret)
164                         return ret;
165                 if (cmd->wait_us > 0)
166                         usleep_range(cmd->wait_us, cmd->wait_max_us);
167                 /* transfer response read if needed */
168                 if (cmd->response_word_nb > 0) {
169                         ret = icp10100_i2c_xfer(st->client->adapter, &msgs[1], 1);
170                         if (ret)
171                                 return ret;
172                 } else {
173                         return 0;
174                 }
175         }
176
177         /* process read words with crc checking */
178         for (i = 0; i < cmd->response_word_nb; ++i) {
179                 ptr = &data[i * ICP10100_RESPONSE_WORD_LENGTH];
180                 crc = crc8(icp10100_crc8_table, ptr, ICP10100_CRC8_WORD_LENGTH,
181                            ICP10100_CRC8_INIT);
182                 if (crc != ptr[ICP10100_CRC8_WORD_LENGTH]) {
183                         dev_err(&st->client->dev, "crc error recv=%#x calc=%#x\n",
184                                 ptr[ICP10100_CRC8_WORD_LENGTH], crc);
185                         return -EIO;
186                 }
187                 *buf_ptr++ = ptr[0];
188                 *buf_ptr++ = ptr[1];
189         }
190
191         return 0;
192 }
193
194 static int icp10100_read_cal_otp(struct icp10100_state *st)
195 {
196         __be16 val;
197         int i;
198         int ret;
199
200         /* switch into OTP read mode */
201         ret = i2c_master_send(st->client, icp10100_switch_mode_otp,
202                               ARRAY_SIZE(icp10100_switch_mode_otp));
203         if (ret < 0)
204                 return ret;
205         if (ret != ARRAY_SIZE(icp10100_switch_mode_otp))
206                 return -EIO;
207
208         /* read 4 calibration values */
209         for (i = 0; i < 4; ++i) {
210                 ret = icp10100_send_cmd(st, &icp10100_cmd_read_otp,
211                                         &val, sizeof(val));
212                 if (ret)
213                         return ret;
214                 st->cal[i] = be16_to_cpu(val);
215                 dev_dbg(&st->client->dev, "cal[%d] = %d\n", i, st->cal[i]);
216         }
217
218         return 0;
219 }
220
221 static int icp10100_init_chip(struct icp10100_state *st)
222 {
223         __be16 val;
224         uint16_t id;
225         int ret;
226
227         /* read and check id */
228         ret = icp10100_send_cmd(st, &icp10100_cmd_read_id, &val, sizeof(val));
229         if (ret)
230                 return ret;
231         id = ICP10100_ID_REG_GET(be16_to_cpu(val));
232         if (id != ICP10100_ID_REG) {
233                 dev_err(&st->client->dev, "invalid id %#x\n", id);
234                 return -ENODEV;
235         }
236
237         /* read calibration data from OTP */
238         ret = icp10100_read_cal_otp(st);
239         if (ret)
240                 return ret;
241
242         /* reset chip */
243         return icp10100_send_cmd(st, &icp10100_cmd_soft_reset, NULL, 0);
244 }
245
246 static int icp10100_get_measures(struct icp10100_state *st,
247                                 uint32_t *pressure, uint16_t *temperature)
248 {
249         const struct icp10100_command *cmd;
250         __be16 measures[3];
251         int ret;
252
253         ret = pm_runtime_resume_and_get(&st->client->dev);
254         if (ret < 0)
255                 return ret;
256
257         mutex_lock(&st->lock);
258         cmd = &icp10100_cmd_measure[st->mode];
259         ret = icp10100_send_cmd(st, cmd, measures, sizeof(measures));
260         mutex_unlock(&st->lock);
261         if (ret)
262                 goto error_measure;
263
264         *pressure = (be16_to_cpu(measures[0]) << 8) |
265                         (be16_to_cpu(measures[1]) >> 8);
266         *temperature = be16_to_cpu(measures[2]);
267
268         pm_runtime_mark_last_busy(&st->client->dev);
269 error_measure:
270         pm_runtime_put_autosuspend(&st->client->dev);
271         return ret;
272 }
273
274 static uint32_t icp10100_get_pressure(struct icp10100_state *st,
275                                       uint32_t raw_pressure, uint16_t raw_temp)
276 {
277         static int32_t p_calib[] = {45000, 80000, 105000};
278         static int32_t lut_lower = 3670016;
279         static int32_t lut_upper = 12058624;
280         static int32_t inv_quadr_factor = 16777216;
281         static int32_t offset_factor = 2048;
282         int64_t val1, val2;
283         int32_t p_lut[3];
284         int32_t t, t_square;
285         int64_t a, b, c;
286         uint32_t pressure_mPa;
287
288         dev_dbg(&st->client->dev, "raw: pressure = %u, temp = %u\n",
289                 raw_pressure, raw_temp);
290
291         /* compute p_lut values */
292         t = (int32_t)raw_temp - 32768;
293         t_square = t * t;
294         val1 = (int64_t)st->cal[0] * (int64_t)t_square;
295         p_lut[0] = lut_lower + (int32_t)div_s64(val1, inv_quadr_factor);
296         val1 = (int64_t)st->cal[1] * (int64_t)t_square;
297         p_lut[1] = offset_factor * st->cal[3] +
298                         (int32_t)div_s64(val1, inv_quadr_factor);
299         val1 = (int64_t)st->cal[2] * (int64_t)t_square;
300         p_lut[2] = lut_upper + (int32_t)div_s64(val1, inv_quadr_factor);
301         dev_dbg(&st->client->dev, "p_lut = [%d, %d, %d]\n",
302                 p_lut[0], p_lut[1], p_lut[2]);
303
304         /* compute a, b, c factors */
305         val1 = (int64_t)p_lut[0] * (int64_t)p_lut[1] *
306                         (int64_t)(p_calib[0] - p_calib[1]) +
307                 (int64_t)p_lut[1] * (int64_t)p_lut[2] *
308                         (int64_t)(p_calib[1] - p_calib[2]) +
309                 (int64_t)p_lut[2] * (int64_t)p_lut[0] *
310                         (int64_t)(p_calib[2] - p_calib[0]);
311         val2 = (int64_t)p_lut[2] * (int64_t)(p_calib[0] - p_calib[1]) +
312                 (int64_t)p_lut[0] * (int64_t)(p_calib[1] - p_calib[2]) +
313                 (int64_t)p_lut[1] * (int64_t)(p_calib[2] - p_calib[0]);
314         c = div64_s64(val1, val2);
315         dev_dbg(&st->client->dev, "val1 = %lld, val2 = %lld, c = %lld\n",
316                 val1, val2, c);
317         val1 = (int64_t)p_calib[0] * (int64_t)p_lut[0] -
318                 (int64_t)p_calib[1] * (int64_t)p_lut[1] -
319                 (int64_t)(p_calib[1] - p_calib[0]) * c;
320         val2 = (int64_t)p_lut[0] - (int64_t)p_lut[1];
321         a = div64_s64(val1, val2);
322         dev_dbg(&st->client->dev, "val1 = %lld, val2 = %lld, a = %lld\n",
323                 val1, val2, a);
324         b = ((int64_t)p_calib[0] - a) * ((int64_t)p_lut[0] + c);
325         dev_dbg(&st->client->dev, "b = %lld\n", b);
326
327         /*
328          * pressure_Pa = a + (b / (c + raw_pressure))
329          * pressure_mPa = 1000 * pressure_Pa
330          */
331         pressure_mPa = 1000LL * a + div64_s64(1000LL * b, c + raw_pressure);
332
333         return pressure_mPa;
334 }
335
336 static int icp10100_read_raw_measures(struct iio_dev *indio_dev,
337                                       struct iio_chan_spec const *chan,
338                                       int *val, int *val2)
339 {
340         struct icp10100_state *st = iio_priv(indio_dev);
341         uint32_t raw_pressure;
342         uint16_t raw_temp;
343         uint32_t pressure_mPa;
344         int ret;
345
346         ret = iio_device_claim_direct_mode(indio_dev);
347         if (ret)
348                 return ret;
349
350         ret = icp10100_get_measures(st, &raw_pressure, &raw_temp);
351         if (ret)
352                 goto error_release;
353
354         switch (chan->type) {
355         case IIO_PRESSURE:
356                 pressure_mPa = icp10100_get_pressure(st, raw_pressure,
357                                                      raw_temp);
358                 /* mPa to kPa */
359                 *val = pressure_mPa / 1000000;
360                 *val2 = pressure_mPa % 1000000;
361                 ret = IIO_VAL_INT_PLUS_MICRO;
362                 break;
363         case IIO_TEMP:
364                 *val = raw_temp;
365                 ret = IIO_VAL_INT;
366                 break;
367         default:
368                 ret = -EINVAL;
369                 break;
370         }
371
372 error_release:
373         iio_device_release_direct_mode(indio_dev);
374         return ret;
375 }
376
377 static int icp10100_read_raw(struct iio_dev *indio_dev,
378                              struct iio_chan_spec const *chan,
379                              int *val, int *val2, long mask)
380 {
381         struct icp10100_state *st = iio_priv(indio_dev);
382
383         switch (mask) {
384         case IIO_CHAN_INFO_RAW:
385         case IIO_CHAN_INFO_PROCESSED:
386                 return icp10100_read_raw_measures(indio_dev, chan, val, val2);
387         case IIO_CHAN_INFO_SCALE:
388                 switch (chan->type) {
389                 case IIO_TEMP:
390                         /* 1000 * 175°C / 65536 in m°C */
391                         *val = 2;
392                         *val2 = 670288;
393                         return IIO_VAL_INT_PLUS_MICRO;
394                 default:
395                         return -EINVAL;
396                 }
397                 break;
398         case IIO_CHAN_INFO_OFFSET:
399                 switch (chan->type) {
400                 case IIO_TEMP:
401                         /* 1000 * -45°C in m°C */
402                         *val = -45000;
403                         return IIO_VAL_INT;
404                 default:
405                         return -EINVAL;
406                 }
407                 break;
408         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
409                 mutex_lock(&st->lock);
410                 *val = 1 << st->mode;
411                 mutex_unlock(&st->lock);
412                 return IIO_VAL_INT;
413         default:
414                 return -EINVAL;
415         }
416 }
417
418 static int icp10100_read_avail(struct iio_dev *indio_dev,
419                                struct iio_chan_spec const *chan,
420                                const int **vals, int *type, int *length,
421                                long mask)
422 {
423         static int oversamplings[] = {1, 2, 4, 8};
424
425         switch (mask) {
426         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
427                 *vals = oversamplings;
428                 *type = IIO_VAL_INT;
429                 *length = ARRAY_SIZE(oversamplings);
430                 return IIO_AVAIL_LIST;
431         default:
432                 return -EINVAL;
433         }
434 }
435
436 static int icp10100_write_raw(struct iio_dev *indio_dev,
437                               struct iio_chan_spec const *chan,
438                               int val, int val2, long mask)
439 {
440         struct icp10100_state *st = iio_priv(indio_dev);
441         unsigned int mode;
442         int ret;
443
444         switch (mask) {
445         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
446                 /* oversampling is always positive and a power of 2 */
447                 if (val <= 0 || !is_power_of_2(val))
448                         return -EINVAL;
449                 mode = ilog2(val);
450                 if (mode >= ICP10100_MODE_NB)
451                         return -EINVAL;
452                 ret = iio_device_claim_direct_mode(indio_dev);
453                 if (ret)
454                         return ret;
455                 mutex_lock(&st->lock);
456                 st->mode = mode;
457                 mutex_unlock(&st->lock);
458                 iio_device_release_direct_mode(indio_dev);
459                 return 0;
460         default:
461                 return -EINVAL;
462         }
463 }
464
465 static int icp10100_write_raw_get_fmt(struct iio_dev *indio_dev,
466                                       struct iio_chan_spec const *chan,
467                                       long mask)
468 {
469         switch (mask) {
470         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
471                 return IIO_VAL_INT;
472         default:
473                 return -EINVAL;
474         }
475 }
476
477 static const struct iio_info icp10100_info = {
478         .read_raw = icp10100_read_raw,
479         .read_avail = icp10100_read_avail,
480         .write_raw = icp10100_write_raw,
481         .write_raw_get_fmt = icp10100_write_raw_get_fmt,
482 };
483
484 static const struct iio_chan_spec icp10100_channels[] = {
485         {
486                 .type = IIO_PRESSURE,
487                 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
488                 .info_mask_shared_by_all =
489                         BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
490                 .info_mask_shared_by_all_available =
491                         BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
492         }, {
493                 .type = IIO_TEMP,
494                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
495                         BIT(IIO_CHAN_INFO_SCALE) |
496                         BIT(IIO_CHAN_INFO_OFFSET),
497                 .info_mask_shared_by_all =
498                         BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
499                 .info_mask_shared_by_all_available =
500                         BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
501         },
502 };
503
504 static int icp10100_enable_regulator(struct icp10100_state *st)
505 {
506         int ret;
507
508         ret = regulator_enable(st->vdd);
509         if (ret)
510                 return ret;
511         msleep(100);
512
513         return 0;
514 }
515
516 static void icp10100_disable_regulator_action(void *data)
517 {
518         struct icp10100_state *st = data;
519         int ret;
520
521         ret = regulator_disable(st->vdd);
522         if (ret)
523                 dev_err(&st->client->dev, "error %d disabling vdd\n", ret);
524 }
525
526 static void icp10100_pm_disable(void *data)
527 {
528         struct device *dev = data;
529
530         pm_runtime_disable(dev);
531 }
532
533 static int icp10100_probe(struct i2c_client *client)
534 {
535         struct iio_dev *indio_dev;
536         struct icp10100_state *st;
537         int ret;
538
539         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
540                 dev_err(&client->dev, "plain i2c transactions not supported\n");
541                 return -ENODEV;
542         }
543
544         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
545         if (!indio_dev)
546                 return -ENOMEM;
547
548         i2c_set_clientdata(client, indio_dev);
549         indio_dev->name = client->name;
550         indio_dev->modes = INDIO_DIRECT_MODE;
551         indio_dev->channels = icp10100_channels;
552         indio_dev->num_channels = ARRAY_SIZE(icp10100_channels);
553         indio_dev->info = &icp10100_info;
554
555         st = iio_priv(indio_dev);
556         mutex_init(&st->lock);
557         st->client = client;
558         st->mode = ICP10100_MODE_N;
559
560         st->vdd = devm_regulator_get(&client->dev, "vdd");
561         if (IS_ERR(st->vdd))
562                 return PTR_ERR(st->vdd);
563
564         ret = icp10100_enable_regulator(st);
565         if (ret)
566                 return ret;
567
568         ret = devm_add_action_or_reset(&client->dev,
569                                        icp10100_disable_regulator_action, st);
570         if (ret)
571                 return ret;
572
573         /* has to be done before the first i2c communication */
574         crc8_populate_msb(icp10100_crc8_table, ICP10100_CRC8_POLYNOMIAL);
575
576         ret = icp10100_init_chip(st);
577         if (ret) {
578                 dev_err(&client->dev, "init chip error %d\n", ret);
579                 return ret;
580         }
581
582         /* enable runtime pm with autosuspend delay of 2s */
583         pm_runtime_get_noresume(&client->dev);
584         pm_runtime_set_active(&client->dev);
585         pm_runtime_enable(&client->dev);
586         pm_runtime_set_autosuspend_delay(&client->dev, 2000);
587         pm_runtime_use_autosuspend(&client->dev);
588         pm_runtime_put(&client->dev);
589         ret = devm_add_action_or_reset(&client->dev, icp10100_pm_disable,
590                                        &client->dev);
591         if (ret)
592                 return ret;
593
594         return devm_iio_device_register(&client->dev, indio_dev);
595 }
596
597 static int icp10100_suspend(struct device *dev)
598 {
599         struct icp10100_state *st = iio_priv(dev_get_drvdata(dev));
600         int ret;
601
602         mutex_lock(&st->lock);
603         ret = regulator_disable(st->vdd);
604         mutex_unlock(&st->lock);
605
606         return ret;
607 }
608
609 static int icp10100_resume(struct device *dev)
610 {
611         struct icp10100_state *st = iio_priv(dev_get_drvdata(dev));
612         int ret;
613
614         mutex_lock(&st->lock);
615
616         ret = icp10100_enable_regulator(st);
617         if (ret)
618                 goto out_unlock;
619
620         /* reset chip */
621         ret = icp10100_send_cmd(st, &icp10100_cmd_soft_reset, NULL, 0);
622
623 out_unlock:
624         mutex_unlock(&st->lock);
625         return ret;
626 }
627
628 static DEFINE_RUNTIME_DEV_PM_OPS(icp10100_pm, icp10100_suspend, icp10100_resume,
629                                  NULL);
630
631 static const struct of_device_id icp10100_of_match[] = {
632         {
633                 .compatible = "invensense,icp10100",
634         },
635         { }
636 };
637 MODULE_DEVICE_TABLE(of, icp10100_of_match);
638
639 static const struct i2c_device_id icp10100_id[] = {
640         { "icp10100", 0 },
641         { }
642 };
643 MODULE_DEVICE_TABLE(i2c, icp10100_id);
644
645 static struct i2c_driver icp10100_driver = {
646         .driver = {
647                 .name = "icp10100",
648                 .pm = pm_ptr(&icp10100_pm),
649                 .of_match_table = icp10100_of_match,
650         },
651         .probe = icp10100_probe,
652         .id_table = icp10100_id,
653 };
654 module_i2c_driver(icp10100_driver);
655
656 MODULE_AUTHOR("InvenSense, Inc.");
657 MODULE_DESCRIPTION("InvenSense icp10100 driver");
658 MODULE_LICENSE("GPL");