1 // SPDX-License-Identifier: GPL-2.0
2
3 /*
4 * System Control and Management Interface(SCMI) based IIO sensor driver
5 *
6 * Copyright (C) 2021 Google LLC
7 */
8
9 #include <linux/delay.h>
10 #include <linux/err.h>
11 #include <linux/iio/buffer.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/kfifo_buf.h>
14 #include <linux/iio/sysfs.h>
15 #include <linux/kernel.h>
16 #include <linux/kthread.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/scmi_protocol.h>
20 #include <linux/time.h>
21 #include <linux/types.h>
22 #include <linux/units.h>
23
24 #define SCMI_IIO_NUM_OF_AXIS 3
25
26 struct scmi_iio_priv {
27 const struct scmi_sensor_proto_ops *sensor_ops;
28 struct scmi_protocol_handle *ph;
29 const struct scmi_sensor_info *sensor_info;
30 struct iio_dev *indio_dev;
31 /* lock to protect against multiple access to the device */
32 struct mutex lock;
33 /* adding one additional channel for timestamp */
34 s64 iio_buf[SCMI_IIO_NUM_OF_AXIS + 1];
35 struct notifier_block sensor_update_nb;
36 u32 *freq_avail;
37 };
38
scmi_iio_sensor_update_cb(struct notifier_block * nb,unsigned long event,void * data)39 static int scmi_iio_sensor_update_cb(struct notifier_block *nb,
40 unsigned long event, void *data)
41 {
42 struct scmi_sensor_update_report *sensor_update = data;
43 struct iio_dev *scmi_iio_dev;
44 struct scmi_iio_priv *sensor;
45 s8 tstamp_scale;
46 u64 time, time_ns;
47 int i;
48
49 if (sensor_update->readings_count == 0)
50 return NOTIFY_DONE;
51
52 sensor = container_of(nb, struct scmi_iio_priv, sensor_update_nb);
53
54 for (i = 0; i < sensor_update->readings_count; i++)
55 sensor->iio_buf[i] = sensor_update->readings[i].value;
56
57 if (!sensor->sensor_info->timestamped) {
58 time_ns = ktime_to_ns(sensor_update->timestamp);
59 } else {
60 /*
61 * All the axes are supposed to have the same value for timestamp.
62 * We are just using the values from the Axis 0 here.
63 */
64 time = sensor_update->readings[0].timestamp;
65
66 /*
67 * Timestamp returned by SCMI is in seconds and is equal to
68 * time * power-of-10 multiplier(tstamp_scale) seconds.
69 * Converting the timestamp to nanoseconds below.
70 */
71 tstamp_scale = sensor->sensor_info->tstamp_scale +
72 const_ilog2(NSEC_PER_SEC) / const_ilog2(10);
73 if (tstamp_scale < 0) {
74 do_div(time, int_pow(10, abs(tstamp_scale)));
75 time_ns = time;
76 } else {
77 time_ns = time * int_pow(10, tstamp_scale);
78 }
79 }
80
81 scmi_iio_dev = sensor->indio_dev;
82 iio_push_to_buffers_with_timestamp(scmi_iio_dev, sensor->iio_buf,
83 time_ns);
84 return NOTIFY_OK;
85 }
86
scmi_iio_buffer_preenable(struct iio_dev * iio_dev)87 static int scmi_iio_buffer_preenable(struct iio_dev *iio_dev)
88 {
89 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
90 u32 sensor_config = 0;
91 int err;
92
93 if (sensor->sensor_info->timestamped)
94 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_TSTAMP_ENABLED_MASK,
95 SCMI_SENS_CFG_TSTAMP_ENABLE);
96
97 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
98 SCMI_SENS_CFG_SENSOR_ENABLE);
99 err = sensor->sensor_ops->config_set(sensor->ph,
100 sensor->sensor_info->id,
101 sensor_config);
102 if (err)
103 dev_err(&iio_dev->dev, "Error in enabling sensor %s err %d",
104 sensor->sensor_info->name, err);
105
106 return err;
107 }
108
scmi_iio_buffer_postdisable(struct iio_dev * iio_dev)109 static int scmi_iio_buffer_postdisable(struct iio_dev *iio_dev)
110 {
111 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
112 u32 sensor_config = 0;
113 int err;
114
115 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
116 SCMI_SENS_CFG_SENSOR_DISABLE);
117 err = sensor->sensor_ops->config_set(sensor->ph,
118 sensor->sensor_info->id,
119 sensor_config);
120 if (err) {
121 dev_err(&iio_dev->dev,
122 "Error in disabling sensor %s with err %d",
123 sensor->sensor_info->name, err);
124 }
125
126 return err;
127 }
128
129 static const struct iio_buffer_setup_ops scmi_iio_buffer_ops = {
130 .preenable = scmi_iio_buffer_preenable,
131 .postdisable = scmi_iio_buffer_postdisable,
132 };
133
scmi_iio_set_odr_val(struct iio_dev * iio_dev,int val,int val2)134 static int scmi_iio_set_odr_val(struct iio_dev *iio_dev, int val, int val2)
135 {
136 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
137 u64 sec, mult, uHz, sf;
138 u32 sensor_config;
139 char buf[32];
140
141 int err = sensor->sensor_ops->config_get(sensor->ph,
142 sensor->sensor_info->id,
143 &sensor_config);
144 if (err) {
145 dev_err(&iio_dev->dev,
146 "Error in getting sensor config for sensor %s err %d",
147 sensor->sensor_info->name, err);
148 return err;
149 }
150
151 uHz = val * MICROHZ_PER_HZ + val2;
152
153 /*
154 * The seconds field in the sensor interval in SCMI is 16 bits long
155 * Therefore seconds = 1/Hz <= 0xFFFF. As floating point calculations are
156 * discouraged in the kernel driver code, to calculate the scale factor (sf)
157 * (1* 1000000 * sf)/uHz <= 0xFFFF. Therefore, sf <= (uHz * 0xFFFF)/1000000
158 * To calculate the multiplier,we convert the sf into char string and
159 * count the number of characters
160 */
161 sf = (u64)uHz * 0xFFFF;
162 do_div(sf, MICROHZ_PER_HZ);
163 mult = scnprintf(buf, sizeof(buf), "%llu", sf) - 1;
164
165 sec = int_pow(10, mult) * MICROHZ_PER_HZ;
166 do_div(sec, uHz);
167 if (sec == 0) {
168 dev_err(&iio_dev->dev,
169 "Trying to set invalid sensor update value for sensor %s",
170 sensor->sensor_info->name);
171 return -EINVAL;
172 }
173
174 sensor_config &= ~SCMI_SENS_CFG_UPDATE_SECS_MASK;
175 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_UPDATE_SECS_MASK, sec);
176 sensor_config &= ~SCMI_SENS_CFG_UPDATE_EXP_MASK;
177 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_UPDATE_EXP_MASK, -mult);
178
179 if (sensor->sensor_info->timestamped) {
180 sensor_config &= ~SCMI_SENS_CFG_TSTAMP_ENABLED_MASK;
181 sensor_config |= FIELD_PREP(SCMI_SENS_CFG_TSTAMP_ENABLED_MASK,
182 SCMI_SENS_CFG_TSTAMP_ENABLE);
183 }
184
185 sensor_config &= ~SCMI_SENS_CFG_ROUND_MASK;
186 sensor_config |=
187 FIELD_PREP(SCMI_SENS_CFG_ROUND_MASK, SCMI_SENS_CFG_ROUND_AUTO);
188
189 err = sensor->sensor_ops->config_set(sensor->ph,
190 sensor->sensor_info->id,
191 sensor_config);
192 if (err)
193 dev_err(&iio_dev->dev,
194 "Error in setting sensor update interval for sensor %s value %u err %d",
195 sensor->sensor_info->name, sensor_config, err);
196
197 return err;
198 }
199
scmi_iio_write_raw(struct iio_dev * iio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)200 static int scmi_iio_write_raw(struct iio_dev *iio_dev,
201 struct iio_chan_spec const *chan, int val,
202 int val2, long mask)
203 {
204 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
205 int err;
206
207 switch (mask) {
208 case IIO_CHAN_INFO_SAMP_FREQ:
209 mutex_lock(&sensor->lock);
210 err = scmi_iio_set_odr_val(iio_dev, val, val2);
211 mutex_unlock(&sensor->lock);
212 return err;
213 default:
214 return -EINVAL;
215 }
216 }
217
scmi_iio_read_avail(struct iio_dev * iio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)218 static int scmi_iio_read_avail(struct iio_dev *iio_dev,
219 struct iio_chan_spec const *chan,
220 const int **vals, int *type, int *length,
221 long mask)
222 {
223 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
224
225 switch (mask) {
226 case IIO_CHAN_INFO_SAMP_FREQ:
227 *vals = sensor->freq_avail;
228 *type = IIO_VAL_INT_PLUS_MICRO;
229 *length = sensor->sensor_info->intervals.count * 2;
230 if (sensor->sensor_info->intervals.segmented)
231 return IIO_AVAIL_RANGE;
232 else
233 return IIO_AVAIL_LIST;
234 default:
235 return -EINVAL;
236 }
237 }
238
convert_ns_to_freq(u64 interval_ns,u64 * hz,u64 * uhz)239 static void convert_ns_to_freq(u64 interval_ns, u64 *hz, u64 *uhz)
240 {
241 u64 rem, freq;
242
243 freq = NSEC_PER_SEC;
244 rem = do_div(freq, interval_ns);
245 *hz = freq;
246 *uhz = rem * 1000000UL;
247 do_div(*uhz, interval_ns);
248 }
249
scmi_iio_get_odr_val(struct iio_dev * iio_dev,int * val,int * val2)250 static int scmi_iio_get_odr_val(struct iio_dev *iio_dev, int *val, int *val2)
251 {
252 u64 sensor_update_interval, sensor_interval_mult, hz, uhz;
253 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
254 u32 sensor_config;
255 int mult;
256
257 int err = sensor->sensor_ops->config_get(sensor->ph,
258 sensor->sensor_info->id,
259 &sensor_config);
260 if (err) {
261 dev_err(&iio_dev->dev,
262 "Error in getting sensor config for sensor %s err %d",
263 sensor->sensor_info->name, err);
264 return err;
265 }
266
267 sensor_update_interval =
268 SCMI_SENS_CFG_GET_UPDATE_SECS(sensor_config) * NSEC_PER_SEC;
269
270 mult = SCMI_SENS_CFG_GET_UPDATE_EXP(sensor_config);
271 if (mult < 0) {
272 sensor_interval_mult = int_pow(10, abs(mult));
273 do_div(sensor_update_interval, sensor_interval_mult);
274 } else {
275 sensor_interval_mult = int_pow(10, mult);
276 sensor_update_interval =
277 sensor_update_interval * sensor_interval_mult;
278 }
279
280 convert_ns_to_freq(sensor_update_interval, &hz, &uhz);
281 *val = hz;
282 *val2 = uhz;
283 return 0;
284 }
285
scmi_iio_read_channel_data(struct iio_dev * iio_dev,struct iio_chan_spec const * ch,int * val,int * val2)286 static int scmi_iio_read_channel_data(struct iio_dev *iio_dev,
287 struct iio_chan_spec const *ch, int *val, int *val2)
288 {
289 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
290 u32 sensor_config;
291 struct scmi_sensor_reading readings[SCMI_IIO_NUM_OF_AXIS];
292 int err;
293
294 sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
295 SCMI_SENS_CFG_SENSOR_ENABLE);
296 err = sensor->sensor_ops->config_set(
297 sensor->ph, sensor->sensor_info->id, sensor_config);
298 if (err) {
299 dev_err(&iio_dev->dev,
300 "Error in enabling sensor %s err %d",
301 sensor->sensor_info->name, err);
302 return err;
303 }
304
305 err = sensor->sensor_ops->reading_get_timestamped(
306 sensor->ph, sensor->sensor_info->id,
307 sensor->sensor_info->num_axis, readings);
308 if (err) {
309 dev_err(&iio_dev->dev,
310 "Error in reading raw attribute for sensor %s err %d",
311 sensor->sensor_info->name, err);
312 return err;
313 }
314
315 sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
316 SCMI_SENS_CFG_SENSOR_DISABLE);
317 err = sensor->sensor_ops->config_set(
318 sensor->ph, sensor->sensor_info->id, sensor_config);
319 if (err) {
320 dev_err(&iio_dev->dev,
321 "Error in disabling sensor %s err %d",
322 sensor->sensor_info->name, err);
323 return err;
324 }
325
326 *val = lower_32_bits(readings[ch->scan_index].value);
327 *val2 = upper_32_bits(readings[ch->scan_index].value);
328
329 return IIO_VAL_INT_64;
330 }
331
scmi_iio_read_raw(struct iio_dev * iio_dev,struct iio_chan_spec const * ch,int * val,int * val2,long mask)332 static int scmi_iio_read_raw(struct iio_dev *iio_dev,
333 struct iio_chan_spec const *ch, int *val,
334 int *val2, long mask)
335 {
336 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
337 s8 scale;
338 int ret;
339
340 switch (mask) {
341 case IIO_CHAN_INFO_SCALE:
342 scale = sensor->sensor_info->axis[ch->scan_index].scale;
343 if (scale < 0) {
344 *val = 1;
345 *val2 = int_pow(10, abs(scale));
346 return IIO_VAL_FRACTIONAL;
347 }
348 *val = int_pow(10, scale);
349 return IIO_VAL_INT;
350 case IIO_CHAN_INFO_SAMP_FREQ:
351 ret = scmi_iio_get_odr_val(iio_dev, val, val2);
352 return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
353 case IIO_CHAN_INFO_RAW:
354 ret = iio_device_claim_direct_mode(iio_dev);
355 if (ret)
356 return ret;
357
358 ret = scmi_iio_read_channel_data(iio_dev, ch, val, val2);
359 iio_device_release_direct_mode(iio_dev);
360 return ret;
361 default:
362 return -EINVAL;
363 }
364 }
365
366 static const struct iio_info scmi_iio_info = {
367 .read_raw = scmi_iio_read_raw,
368 .read_avail = scmi_iio_read_avail,
369 .write_raw = scmi_iio_write_raw,
370 };
371
scmi_iio_get_raw_available(struct iio_dev * iio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)372 static ssize_t scmi_iio_get_raw_available(struct iio_dev *iio_dev,
373 uintptr_t private,
374 const struct iio_chan_spec *chan,
375 char *buf)
376 {
377 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
378 u64 resolution, rem;
379 s64 min_range, max_range;
380 s8 exponent, scale;
381 int len = 0;
382
383 /*
384 * All the axes are supposed to have the same value for range and resolution.
385 * We are just using the values from the Axis 0 here.
386 */
387 if (sensor->sensor_info->axis[0].extended_attrs) {
388 min_range = sensor->sensor_info->axis[0].attrs.min_range;
389 max_range = sensor->sensor_info->axis[0].attrs.max_range;
390 resolution = sensor->sensor_info->axis[0].resolution;
391 exponent = sensor->sensor_info->axis[0].exponent;
392 scale = sensor->sensor_info->axis[0].scale;
393
394 /*
395 * To provide the raw value for the resolution to the userspace,
396 * need to divide the resolution exponent by the sensor scale
397 */
398 exponent = exponent - scale;
399 if (exponent < 0) {
400 rem = do_div(resolution,
401 int_pow(10, abs(exponent))
402 );
403 len = sysfs_emit(buf,
404 "[%lld %llu.%llu %lld]\n", min_range,
405 resolution, rem, max_range);
406 } else {
407 resolution = resolution * int_pow(10, exponent);
408 len = sysfs_emit(buf, "[%lld %llu %lld]\n",
409 min_range, resolution, max_range);
410 }
411 }
412 return len;
413 }
414
415 static const struct iio_chan_spec_ext_info scmi_iio_ext_info[] = {
416 {
417 .name = "raw_available",
418 .read = scmi_iio_get_raw_available,
419 .shared = IIO_SHARED_BY_TYPE,
420 },
421 {},
422 };
423
scmi_iio_set_timestamp_channel(struct iio_chan_spec * iio_chan,int scan_index)424 static void scmi_iio_set_timestamp_channel(struct iio_chan_spec *iio_chan,
425 int scan_index)
426 {
427 iio_chan->type = IIO_TIMESTAMP;
428 iio_chan->channel = -1;
429 iio_chan->scan_index = scan_index;
430 iio_chan->scan_type.sign = 'u';
431 iio_chan->scan_type.realbits = 64;
432 iio_chan->scan_type.storagebits = 64;
433 }
434
scmi_iio_set_data_channel(struct iio_chan_spec * iio_chan,enum iio_chan_type type,enum iio_modifier mod,int scan_index)435 static void scmi_iio_set_data_channel(struct iio_chan_spec *iio_chan,
436 enum iio_chan_type type,
437 enum iio_modifier mod, int scan_index)
438 {
439 iio_chan->type = type;
440 iio_chan->modified = 1;
441 iio_chan->channel2 = mod;
442 iio_chan->info_mask_separate =
443 BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_RAW);
444 iio_chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ);
445 iio_chan->info_mask_shared_by_type_available =
446 BIT(IIO_CHAN_INFO_SAMP_FREQ);
447 iio_chan->scan_index = scan_index;
448 iio_chan->scan_type.sign = 's';
449 iio_chan->scan_type.realbits = 64;
450 iio_chan->scan_type.storagebits = 64;
451 iio_chan->scan_type.endianness = IIO_LE;
452 iio_chan->ext_info = scmi_iio_ext_info;
453 }
454
scmi_iio_get_chan_modifier(const char * name,enum iio_modifier * modifier)455 static int scmi_iio_get_chan_modifier(const char *name,
456 enum iio_modifier *modifier)
457 {
458 char *pch, mod;
459
460 if (!name)
461 return -EINVAL;
462
463 pch = strrchr(name, '_');
464 if (!pch)
465 return -EINVAL;
466
467 mod = *(pch + 1);
468 switch (mod) {
469 case 'X':
470 *modifier = IIO_MOD_X;
471 return 0;
472 case 'Y':
473 *modifier = IIO_MOD_Y;
474 return 0;
475 case 'Z':
476 *modifier = IIO_MOD_Z;
477 return 0;
478 default:
479 return -EINVAL;
480 }
481 }
482
scmi_iio_get_chan_type(u8 scmi_type,enum iio_chan_type * iio_type)483 static int scmi_iio_get_chan_type(u8 scmi_type, enum iio_chan_type *iio_type)
484 {
485 switch (scmi_type) {
486 case METERS_SEC_SQUARED:
487 *iio_type = IIO_ACCEL;
488 return 0;
489 case RADIANS_SEC:
490 *iio_type = IIO_ANGL_VEL;
491 return 0;
492 default:
493 return -EINVAL;
494 }
495 }
496
scmi_iio_convert_interval_to_ns(u32 val)497 static u64 scmi_iio_convert_interval_to_ns(u32 val)
498 {
499 u64 sensor_update_interval =
500 SCMI_SENS_INTVL_GET_SECS(val) * NSEC_PER_SEC;
501 u64 sensor_interval_mult;
502 int mult;
503
504 mult = SCMI_SENS_INTVL_GET_EXP(val);
505 if (mult < 0) {
506 sensor_interval_mult = int_pow(10, abs(mult));
507 do_div(sensor_update_interval, sensor_interval_mult);
508 } else {
509 sensor_interval_mult = int_pow(10, mult);
510 sensor_update_interval =
511 sensor_update_interval * sensor_interval_mult;
512 }
513 return sensor_update_interval;
514 }
515
scmi_iio_set_sampling_freq_avail(struct iio_dev * iio_dev)516 static int scmi_iio_set_sampling_freq_avail(struct iio_dev *iio_dev)
517 {
518 u64 cur_interval_ns, low_interval_ns, high_interval_ns, step_size_ns,
519 hz, uhz;
520 unsigned int cur_interval, low_interval, high_interval, step_size;
521 struct scmi_iio_priv *sensor = iio_priv(iio_dev);
522 int i;
523
524 sensor->freq_avail =
525 devm_kzalloc(&iio_dev->dev,
526 sizeof(*sensor->freq_avail) *
527 (sensor->sensor_info->intervals.count * 2),
528 GFP_KERNEL);
529 if (!sensor->freq_avail)
530 return -ENOMEM;
531
532 if (sensor->sensor_info->intervals.segmented) {
533 low_interval = sensor->sensor_info->intervals
534 .desc[SCMI_SENS_INTVL_SEGMENT_LOW];
535 low_interval_ns = scmi_iio_convert_interval_to_ns(low_interval);
536 convert_ns_to_freq(low_interval_ns, &hz, &uhz);
537 sensor->freq_avail[0] = hz;
538 sensor->freq_avail[1] = uhz;
539
540 step_size = sensor->sensor_info->intervals
541 .desc[SCMI_SENS_INTVL_SEGMENT_STEP];
542 step_size_ns = scmi_iio_convert_interval_to_ns(step_size);
543 convert_ns_to_freq(step_size_ns, &hz, &uhz);
544 sensor->freq_avail[2] = hz;
545 sensor->freq_avail[3] = uhz;
546
547 high_interval = sensor->sensor_info->intervals
548 .desc[SCMI_SENS_INTVL_SEGMENT_HIGH];
549 high_interval_ns =
550 scmi_iio_convert_interval_to_ns(high_interval);
551 convert_ns_to_freq(high_interval_ns, &hz, &uhz);
552 sensor->freq_avail[4] = hz;
553 sensor->freq_avail[5] = uhz;
554 } else {
555 for (i = 0; i < sensor->sensor_info->intervals.count; i++) {
556 cur_interval = sensor->sensor_info->intervals.desc[i];
557 cur_interval_ns =
558 scmi_iio_convert_interval_to_ns(cur_interval);
559 convert_ns_to_freq(cur_interval_ns, &hz, &uhz);
560 sensor->freq_avail[i * 2] = hz;
561 sensor->freq_avail[i * 2 + 1] = uhz;
562 }
563 }
564 return 0;
565 }
566
567 static struct iio_dev *
scmi_alloc_iiodev(struct scmi_device * sdev,const struct scmi_sensor_proto_ops * ops,struct scmi_protocol_handle * ph,const struct scmi_sensor_info * sensor_info)568 scmi_alloc_iiodev(struct scmi_device *sdev,
569 const struct scmi_sensor_proto_ops *ops,
570 struct scmi_protocol_handle *ph,
571 const struct scmi_sensor_info *sensor_info)
572 {
573 struct iio_chan_spec *iio_channels;
574 struct scmi_iio_priv *sensor;
575 enum iio_modifier modifier;
576 enum iio_chan_type type;
577 struct iio_dev *iiodev;
578 struct device *dev = &sdev->dev;
579 const struct scmi_handle *handle = sdev->handle;
580 int i, ret;
581
582 iiodev = devm_iio_device_alloc(dev, sizeof(*sensor));
583 if (!iiodev)
584 return ERR_PTR(-ENOMEM);
585
586 iiodev->modes = INDIO_DIRECT_MODE;
587 sensor = iio_priv(iiodev);
588 sensor->sensor_ops = ops;
589 sensor->ph = ph;
590 sensor->sensor_info = sensor_info;
591 sensor->sensor_update_nb.notifier_call = scmi_iio_sensor_update_cb;
592 sensor->indio_dev = iiodev;
593 mutex_init(&sensor->lock);
594
595 /* adding one additional channel for timestamp */
596 iiodev->num_channels = sensor_info->num_axis + 1;
597 iiodev->name = sensor_info->name;
598 iiodev->info = &scmi_iio_info;
599
600 iio_channels =
601 devm_kzalloc(dev,
602 sizeof(*iio_channels) * (iiodev->num_channels),
603 GFP_KERNEL);
604 if (!iio_channels)
605 return ERR_PTR(-ENOMEM);
606
607 ret = scmi_iio_set_sampling_freq_avail(iiodev);
608 if (ret < 0)
609 return ERR_PTR(ret);
610
611 for (i = 0; i < sensor_info->num_axis; i++) {
612 ret = scmi_iio_get_chan_type(sensor_info->axis[i].type, &type);
613 if (ret < 0)
614 return ERR_PTR(ret);
615
616 ret = scmi_iio_get_chan_modifier(sensor_info->axis[i].name,
617 &modifier);
618 if (ret < 0)
619 return ERR_PTR(ret);
620
621 scmi_iio_set_data_channel(&iio_channels[i], type, modifier,
622 sensor_info->axis[i].id);
623 }
624
625 ret = handle->notify_ops->devm_event_notifier_register(sdev,
626 SCMI_PROTOCOL_SENSOR, SCMI_EVENT_SENSOR_UPDATE,
627 &sensor->sensor_info->id,
628 &sensor->sensor_update_nb);
629 if (ret) {
630 dev_err(&iiodev->dev,
631 "Error in registering sensor update notifier for sensor %s err %d",
632 sensor->sensor_info->name, ret);
633 return ERR_PTR(ret);
634 }
635
636 scmi_iio_set_timestamp_channel(&iio_channels[i], i);
637 iiodev->channels = iio_channels;
638 return iiodev;
639 }
640
scmi_iio_dev_probe(struct scmi_device * sdev)641 static int scmi_iio_dev_probe(struct scmi_device *sdev)
642 {
643 const struct scmi_sensor_info *sensor_info;
644 struct scmi_handle *handle = sdev->handle;
645 const struct scmi_sensor_proto_ops *sensor_ops;
646 struct scmi_protocol_handle *ph;
647 struct device *dev = &sdev->dev;
648 struct iio_dev *scmi_iio_dev;
649 u16 nr_sensors;
650 int err = -ENODEV, i;
651
652 if (!handle)
653 return -ENODEV;
654
655 sensor_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_SENSOR, &ph);
656 if (IS_ERR(sensor_ops)) {
657 dev_err(dev, "SCMI device has no sensor interface\n");
658 return PTR_ERR(sensor_ops);
659 }
660
661 nr_sensors = sensor_ops->count_get(ph);
662 if (!nr_sensors) {
663 dev_dbg(dev, "0 sensors found via SCMI bus\n");
664 return -ENODEV;
665 }
666
667 for (i = 0; i < nr_sensors; i++) {
668 sensor_info = sensor_ops->info_get(ph, i);
669 if (!sensor_info) {
670 dev_err(dev, "SCMI sensor %d has missing info\n", i);
671 return -EINVAL;
672 }
673
674 /* This driver only supports 3-axis accel and gyro, skipping other sensors */
675 if (sensor_info->num_axis != SCMI_IIO_NUM_OF_AXIS)
676 continue;
677
678 /* This driver only supports 3-axis accel and gyro, skipping other sensors */
679 if (sensor_info->axis[0].type != METERS_SEC_SQUARED &&
680 sensor_info->axis[0].type != RADIANS_SEC)
681 continue;
682
683 scmi_iio_dev = scmi_alloc_iiodev(sdev, sensor_ops, ph,
684 sensor_info);
685 if (IS_ERR(scmi_iio_dev)) {
686 dev_err(dev,
687 "failed to allocate IIO device for sensor %s: %ld\n",
688 sensor_info->name, PTR_ERR(scmi_iio_dev));
689 return PTR_ERR(scmi_iio_dev);
690 }
691
692 err = devm_iio_kfifo_buffer_setup(&scmi_iio_dev->dev,
693 scmi_iio_dev,
694 &scmi_iio_buffer_ops);
695 if (err < 0) {
696 dev_err(dev,
697 "IIO buffer setup error at sensor %s: %d\n",
698 sensor_info->name, err);
699 return err;
700 }
701
702 err = devm_iio_device_register(dev, scmi_iio_dev);
703 if (err) {
704 dev_err(dev,
705 "IIO device registration failed at sensor %s: %d\n",
706 sensor_info->name, err);
707 return err;
708 }
709 }
710 return err;
711 }
712
713 static const struct scmi_device_id scmi_id_table[] = {
714 { SCMI_PROTOCOL_SENSOR, "iiodev" },
715 {},
716 };
717
718 MODULE_DEVICE_TABLE(scmi, scmi_id_table);
719
720 static struct scmi_driver scmi_iiodev_driver = {
721 .name = "scmi-sensor-iiodev",
722 .probe = scmi_iio_dev_probe,
723 .id_table = scmi_id_table,
724 };
725
726 module_scmi_driver(scmi_iiodev_driver);
727
728 MODULE_AUTHOR("Jyoti Bhayana <jbhayana@google.com>");
729 MODULE_DESCRIPTION("SCMI IIO Driver");
730 MODULE_LICENSE("GPL v2");
731