1 // SPDX-License-Identifier: GPL-2.0-only
2 /* The industrial I/O core in kernel channel mapping
3 *
4 * Copyright (c) 2011 Jonathan Cameron
5 */
6 #include <linux/err.h>
7 #include <linux/export.h>
8 #include <linux/slab.h>
9 #include <linux/mutex.h>
10 #include <linux/of.h>
11
12 #include <linux/iio/iio.h>
13 #include <linux/iio/iio-opaque.h>
14 #include "iio_core.h"
15 #include <linux/iio/machine.h>
16 #include <linux/iio/driver.h>
17 #include <linux/iio/consumer.h>
18
19 struct iio_map_internal {
20 struct iio_dev *indio_dev;
21 struct iio_map *map;
22 struct list_head l;
23 };
24
25 static LIST_HEAD(iio_map_list);
26 static DEFINE_MUTEX(iio_map_list_lock);
27
iio_map_array_unregister_locked(struct iio_dev * indio_dev)28 static int iio_map_array_unregister_locked(struct iio_dev *indio_dev)
29 {
30 int ret = -ENODEV;
31 struct iio_map_internal *mapi, *next;
32
33 list_for_each_entry_safe(mapi, next, &iio_map_list, l) {
34 if (indio_dev == mapi->indio_dev) {
35 list_del(&mapi->l);
36 kfree(mapi);
37 ret = 0;
38 }
39 }
40 return ret;
41 }
42
iio_map_array_register(struct iio_dev * indio_dev,struct iio_map * maps)43 int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps)
44 {
45 int i = 0, ret = 0;
46 struct iio_map_internal *mapi;
47
48 if (maps == NULL)
49 return 0;
50
51 mutex_lock(&iio_map_list_lock);
52 while (maps[i].consumer_dev_name != NULL) {
53 mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
54 if (mapi == NULL) {
55 ret = -ENOMEM;
56 goto error_ret;
57 }
58 mapi->map = &maps[i];
59 mapi->indio_dev = indio_dev;
60 list_add_tail(&mapi->l, &iio_map_list);
61 i++;
62 }
63 error_ret:
64 if (ret)
65 iio_map_array_unregister_locked(indio_dev);
66 mutex_unlock(&iio_map_list_lock);
67
68 return ret;
69 }
70 EXPORT_SYMBOL_GPL(iio_map_array_register);
71
72
73 /*
74 * Remove all map entries associated with the given iio device
75 */
iio_map_array_unregister(struct iio_dev * indio_dev)76 int iio_map_array_unregister(struct iio_dev *indio_dev)
77 {
78 int ret;
79
80 mutex_lock(&iio_map_list_lock);
81 ret = iio_map_array_unregister_locked(indio_dev);
82 mutex_unlock(&iio_map_list_lock);
83
84 return ret;
85 }
86 EXPORT_SYMBOL_GPL(iio_map_array_unregister);
87
iio_map_array_unregister_cb(void * indio_dev)88 static void iio_map_array_unregister_cb(void *indio_dev)
89 {
90 iio_map_array_unregister(indio_dev);
91 }
92
devm_iio_map_array_register(struct device * dev,struct iio_dev * indio_dev,struct iio_map * maps)93 int devm_iio_map_array_register(struct device *dev, struct iio_dev *indio_dev, struct iio_map *maps)
94 {
95 int ret;
96
97 ret = iio_map_array_register(indio_dev, maps);
98 if (ret)
99 return ret;
100
101 return devm_add_action_or_reset(dev, iio_map_array_unregister_cb, indio_dev);
102 }
103 EXPORT_SYMBOL_GPL(devm_iio_map_array_register);
104
105 static const struct iio_chan_spec
iio_chan_spec_from_name(const struct iio_dev * indio_dev,const char * name)106 *iio_chan_spec_from_name(const struct iio_dev *indio_dev, const char *name)
107 {
108 int i;
109 const struct iio_chan_spec *chan = NULL;
110
111 for (i = 0; i < indio_dev->num_channels; i++)
112 if (indio_dev->channels[i].datasheet_name &&
113 strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
114 chan = &indio_dev->channels[i];
115 break;
116 }
117 return chan;
118 }
119
120 #ifdef CONFIG_OF
121
iio_dev_node_match(struct device * dev,const void * data)122 static int iio_dev_node_match(struct device *dev, const void *data)
123 {
124 return dev->of_node == data && dev->type == &iio_device_type;
125 }
126
127 /**
128 * __of_iio_simple_xlate - translate iiospec to the IIO channel index
129 * @indio_dev: pointer to the iio_dev structure
130 * @iiospec: IIO specifier as found in the device tree
131 *
132 * This is simple translation function, suitable for the most 1:1 mapped
133 * channels in IIO chips. This function performs only one sanity check:
134 * whether IIO index is less than num_channels (that is specified in the
135 * iio_dev).
136 */
__of_iio_simple_xlate(struct iio_dev * indio_dev,const struct of_phandle_args * iiospec)137 static int __of_iio_simple_xlate(struct iio_dev *indio_dev,
138 const struct of_phandle_args *iiospec)
139 {
140 if (!iiospec->args_count)
141 return 0;
142
143 if (iiospec->args[0] >= indio_dev->num_channels) {
144 dev_err(&indio_dev->dev, "invalid channel index %u\n",
145 iiospec->args[0]);
146 return -EINVAL;
147 }
148
149 return iiospec->args[0];
150 }
151
__of_iio_channel_get(struct iio_channel * channel,struct device_node * np,int index)152 static int __of_iio_channel_get(struct iio_channel *channel,
153 struct device_node *np, int index)
154 {
155 struct device *idev;
156 struct iio_dev *indio_dev;
157 int err;
158 struct of_phandle_args iiospec;
159
160 err = of_parse_phandle_with_args(np, "io-channels",
161 "#io-channel-cells",
162 index, &iiospec);
163 if (err)
164 return err;
165
166 idev = bus_find_device(&iio_bus_type, NULL, iiospec.np,
167 iio_dev_node_match);
168 of_node_put(iiospec.np);
169 if (idev == NULL)
170 return -EPROBE_DEFER;
171
172 indio_dev = dev_to_iio_dev(idev);
173 channel->indio_dev = indio_dev;
174 if (indio_dev->info->of_xlate)
175 index = indio_dev->info->of_xlate(indio_dev, &iiospec);
176 else
177 index = __of_iio_simple_xlate(indio_dev, &iiospec);
178 if (index < 0)
179 goto err_put;
180 channel->channel = &indio_dev->channels[index];
181
182 return 0;
183
184 err_put:
185 iio_device_put(indio_dev);
186 return index;
187 }
188
of_iio_channel_get(struct device_node * np,int index)189 static struct iio_channel *of_iio_channel_get(struct device_node *np, int index)
190 {
191 struct iio_channel *channel;
192 int err;
193
194 if (index < 0)
195 return ERR_PTR(-EINVAL);
196
197 channel = kzalloc(sizeof(*channel), GFP_KERNEL);
198 if (channel == NULL)
199 return ERR_PTR(-ENOMEM);
200
201 err = __of_iio_channel_get(channel, np, index);
202 if (err)
203 goto err_free_channel;
204
205 return channel;
206
207 err_free_channel:
208 kfree(channel);
209 return ERR_PTR(err);
210 }
211
of_iio_channel_get_by_name(struct device_node * np,const char * name)212 struct iio_channel *of_iio_channel_get_by_name(struct device_node *np,
213 const char *name)
214 {
215 struct iio_channel *chan = NULL;
216
217 /* Walk up the tree of devices looking for a matching iio channel */
218 while (np) {
219 int index = 0;
220
221 /*
222 * For named iio channels, first look up the name in the
223 * "io-channel-names" property. If it cannot be found, the
224 * index will be an error code, and of_iio_channel_get()
225 * will fail.
226 */
227 if (name)
228 index = of_property_match_string(np, "io-channel-names",
229 name);
230 chan = of_iio_channel_get(np, index);
231 if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER)
232 break;
233 else if (name && index >= 0) {
234 pr_err("ERROR: could not get IIO channel %pOF:%s(%i)\n",
235 np, name ? name : "", index);
236 return NULL;
237 }
238
239 /*
240 * No matching IIO channel found on this node.
241 * If the parent node has a "io-channel-ranges" property,
242 * then we can try one of its channels.
243 */
244 np = np->parent;
245 if (np && !of_get_property(np, "io-channel-ranges", NULL))
246 return NULL;
247 }
248
249 return chan;
250 }
251 EXPORT_SYMBOL_GPL(of_iio_channel_get_by_name);
252
of_iio_channel_get_all(struct device * dev)253 static struct iio_channel *of_iio_channel_get_all(struct device *dev)
254 {
255 struct iio_channel *chans;
256 int i, mapind, nummaps = 0;
257 int ret;
258
259 do {
260 ret = of_parse_phandle_with_args(dev->of_node,
261 "io-channels",
262 "#io-channel-cells",
263 nummaps, NULL);
264 if (ret < 0)
265 break;
266 } while (++nummaps);
267
268 if (nummaps == 0) /* no error, return NULL to search map table */
269 return NULL;
270
271 /* NULL terminated array to save passing size */
272 chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
273 if (chans == NULL)
274 return ERR_PTR(-ENOMEM);
275
276 /* Search for OF matches */
277 for (mapind = 0; mapind < nummaps; mapind++) {
278 ret = __of_iio_channel_get(&chans[mapind], dev->of_node,
279 mapind);
280 if (ret)
281 goto error_free_chans;
282 }
283 return chans;
284
285 error_free_chans:
286 for (i = 0; i < mapind; i++)
287 iio_device_put(chans[i].indio_dev);
288 kfree(chans);
289 return ERR_PTR(ret);
290 }
291
292 #else /* CONFIG_OF */
293
of_iio_channel_get_all(struct device * dev)294 static inline struct iio_channel *of_iio_channel_get_all(struct device *dev)
295 {
296 return NULL;
297 }
298
299 #endif /* CONFIG_OF */
300
iio_channel_get_sys(const char * name,const char * channel_name)301 static struct iio_channel *iio_channel_get_sys(const char *name,
302 const char *channel_name)
303 {
304 struct iio_map_internal *c_i = NULL, *c = NULL;
305 struct iio_channel *channel;
306 int err;
307
308 if (name == NULL && channel_name == NULL)
309 return ERR_PTR(-ENODEV);
310
311 /* first find matching entry the channel map */
312 mutex_lock(&iio_map_list_lock);
313 list_for_each_entry(c_i, &iio_map_list, l) {
314 if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) ||
315 (channel_name &&
316 strcmp(channel_name, c_i->map->consumer_channel) != 0))
317 continue;
318 c = c_i;
319 iio_device_get(c->indio_dev);
320 break;
321 }
322 mutex_unlock(&iio_map_list_lock);
323 if (c == NULL)
324 return ERR_PTR(-ENODEV);
325
326 channel = kzalloc(sizeof(*channel), GFP_KERNEL);
327 if (channel == NULL) {
328 err = -ENOMEM;
329 goto error_no_mem;
330 }
331
332 channel->indio_dev = c->indio_dev;
333
334 if (c->map->adc_channel_label) {
335 channel->channel =
336 iio_chan_spec_from_name(channel->indio_dev,
337 c->map->adc_channel_label);
338
339 if (channel->channel == NULL) {
340 err = -EINVAL;
341 goto error_no_chan;
342 }
343 }
344
345 return channel;
346
347 error_no_chan:
348 kfree(channel);
349 error_no_mem:
350 iio_device_put(c->indio_dev);
351 return ERR_PTR(err);
352 }
353
iio_channel_get(struct device * dev,const char * channel_name)354 struct iio_channel *iio_channel_get(struct device *dev,
355 const char *channel_name)
356 {
357 const char *name = dev ? dev_name(dev) : NULL;
358 struct iio_channel *channel;
359
360 if (dev) {
361 channel = of_iio_channel_get_by_name(dev->of_node,
362 channel_name);
363 if (channel != NULL)
364 return channel;
365 }
366
367 return iio_channel_get_sys(name, channel_name);
368 }
369 EXPORT_SYMBOL_GPL(iio_channel_get);
370
iio_channel_release(struct iio_channel * channel)371 void iio_channel_release(struct iio_channel *channel)
372 {
373 if (!channel)
374 return;
375 iio_device_put(channel->indio_dev);
376 kfree(channel);
377 }
378 EXPORT_SYMBOL_GPL(iio_channel_release);
379
devm_iio_channel_free(void * iio_channel)380 static void devm_iio_channel_free(void *iio_channel)
381 {
382 iio_channel_release(iio_channel);
383 }
384
devm_iio_channel_get(struct device * dev,const char * channel_name)385 struct iio_channel *devm_iio_channel_get(struct device *dev,
386 const char *channel_name)
387 {
388 struct iio_channel *channel;
389 int ret;
390
391 channel = iio_channel_get(dev, channel_name);
392 if (IS_ERR(channel))
393 return channel;
394
395 ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
396 if (ret)
397 return ERR_PTR(ret);
398
399 return channel;
400 }
401 EXPORT_SYMBOL_GPL(devm_iio_channel_get);
402
devm_of_iio_channel_get_by_name(struct device * dev,struct device_node * np,const char * channel_name)403 struct iio_channel *devm_of_iio_channel_get_by_name(struct device *dev,
404 struct device_node *np,
405 const char *channel_name)
406 {
407 struct iio_channel *channel;
408 int ret;
409
410 channel = of_iio_channel_get_by_name(np, channel_name);
411 if (IS_ERR(channel))
412 return channel;
413
414 ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
415 if (ret)
416 return ERR_PTR(ret);
417
418 return channel;
419 }
420 EXPORT_SYMBOL_GPL(devm_of_iio_channel_get_by_name);
421
iio_channel_get_all(struct device * dev)422 struct iio_channel *iio_channel_get_all(struct device *dev)
423 {
424 const char *name;
425 struct iio_channel *chans;
426 struct iio_map_internal *c = NULL;
427 int nummaps = 0;
428 int mapind = 0;
429 int i, ret;
430
431 if (dev == NULL)
432 return ERR_PTR(-EINVAL);
433
434 chans = of_iio_channel_get_all(dev);
435 if (chans)
436 return chans;
437
438 name = dev_name(dev);
439
440 mutex_lock(&iio_map_list_lock);
441 /* first count the matching maps */
442 list_for_each_entry(c, &iio_map_list, l)
443 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
444 continue;
445 else
446 nummaps++;
447
448 if (nummaps == 0) {
449 ret = -ENODEV;
450 goto error_ret;
451 }
452
453 /* NULL terminated array to save passing size */
454 chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
455 if (chans == NULL) {
456 ret = -ENOMEM;
457 goto error_ret;
458 }
459
460 /* for each map fill in the chans element */
461 list_for_each_entry(c, &iio_map_list, l) {
462 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
463 continue;
464 chans[mapind].indio_dev = c->indio_dev;
465 chans[mapind].data = c->map->consumer_data;
466 chans[mapind].channel =
467 iio_chan_spec_from_name(chans[mapind].indio_dev,
468 c->map->adc_channel_label);
469 if (chans[mapind].channel == NULL) {
470 ret = -EINVAL;
471 goto error_free_chans;
472 }
473 iio_device_get(chans[mapind].indio_dev);
474 mapind++;
475 }
476 if (mapind == 0) {
477 ret = -ENODEV;
478 goto error_free_chans;
479 }
480 mutex_unlock(&iio_map_list_lock);
481
482 return chans;
483
484 error_free_chans:
485 for (i = 0; i < nummaps; i++)
486 iio_device_put(chans[i].indio_dev);
487 kfree(chans);
488 error_ret:
489 mutex_unlock(&iio_map_list_lock);
490
491 return ERR_PTR(ret);
492 }
493 EXPORT_SYMBOL_GPL(iio_channel_get_all);
494
iio_channel_release_all(struct iio_channel * channels)495 void iio_channel_release_all(struct iio_channel *channels)
496 {
497 struct iio_channel *chan = &channels[0];
498
499 while (chan->indio_dev) {
500 iio_device_put(chan->indio_dev);
501 chan++;
502 }
503 kfree(channels);
504 }
505 EXPORT_SYMBOL_GPL(iio_channel_release_all);
506
devm_iio_channel_free_all(void * iio_channels)507 static void devm_iio_channel_free_all(void *iio_channels)
508 {
509 iio_channel_release_all(iio_channels);
510 }
511
devm_iio_channel_get_all(struct device * dev)512 struct iio_channel *devm_iio_channel_get_all(struct device *dev)
513 {
514 struct iio_channel *channels;
515 int ret;
516
517 channels = iio_channel_get_all(dev);
518 if (IS_ERR(channels))
519 return channels;
520
521 ret = devm_add_action_or_reset(dev, devm_iio_channel_free_all,
522 channels);
523 if (ret)
524 return ERR_PTR(ret);
525
526 return channels;
527 }
528 EXPORT_SYMBOL_GPL(devm_iio_channel_get_all);
529
iio_channel_read(struct iio_channel * chan,int * val,int * val2,enum iio_chan_info_enum info)530 static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
531 enum iio_chan_info_enum info)
532 {
533 int unused;
534 int vals[INDIO_MAX_RAW_ELEMENTS];
535 int ret;
536 int val_len = 2;
537
538 if (val2 == NULL)
539 val2 = &unused;
540
541 if (!iio_channel_has_info(chan->channel, info))
542 return -EINVAL;
543
544 if (chan->indio_dev->info->read_raw_multi) {
545 ret = chan->indio_dev->info->read_raw_multi(chan->indio_dev,
546 chan->channel, INDIO_MAX_RAW_ELEMENTS,
547 vals, &val_len, info);
548 *val = vals[0];
549 *val2 = vals[1];
550 } else
551 ret = chan->indio_dev->info->read_raw(chan->indio_dev,
552 chan->channel, val, val2, info);
553
554 return ret;
555 }
556
iio_read_channel_raw(struct iio_channel * chan,int * val)557 int iio_read_channel_raw(struct iio_channel *chan, int *val)
558 {
559 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
560 int ret;
561
562 mutex_lock(&iio_dev_opaque->info_exist_lock);
563 if (chan->indio_dev->info == NULL) {
564 ret = -ENODEV;
565 goto err_unlock;
566 }
567
568 ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
569 err_unlock:
570 mutex_unlock(&iio_dev_opaque->info_exist_lock);
571
572 return ret;
573 }
574 EXPORT_SYMBOL_GPL(iio_read_channel_raw);
575
iio_read_channel_average_raw(struct iio_channel * chan,int * val)576 int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
577 {
578 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
579 int ret;
580
581 mutex_lock(&iio_dev_opaque->info_exist_lock);
582 if (chan->indio_dev->info == NULL) {
583 ret = -ENODEV;
584 goto err_unlock;
585 }
586
587 ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
588 err_unlock:
589 mutex_unlock(&iio_dev_opaque->info_exist_lock);
590
591 return ret;
592 }
593 EXPORT_SYMBOL_GPL(iio_read_channel_average_raw);
594
iio_convert_raw_to_processed_unlocked(struct iio_channel * chan,int raw,int * processed,unsigned int scale)595 static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
596 int raw, int *processed, unsigned int scale)
597 {
598 int scale_type, scale_val, scale_val2, offset;
599 s64 raw64 = raw;
600 int ret;
601
602 ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_OFFSET);
603 if (ret >= 0)
604 raw64 += offset;
605
606 scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
607 IIO_CHAN_INFO_SCALE);
608 if (scale_type < 0) {
609 /*
610 * Just pass raw values as processed if no scaling is
611 * available.
612 */
613 *processed = raw;
614 return 0;
615 }
616
617 switch (scale_type) {
618 case IIO_VAL_INT:
619 *processed = raw64 * scale_val;
620 break;
621 case IIO_VAL_INT_PLUS_MICRO:
622 if (scale_val2 < 0)
623 *processed = -raw64 * scale_val;
624 else
625 *processed = raw64 * scale_val;
626 *processed += div_s64(raw64 * (s64)scale_val2 * scale,
627 1000000LL);
628 break;
629 case IIO_VAL_INT_PLUS_NANO:
630 if (scale_val2 < 0)
631 *processed = -raw64 * scale_val;
632 else
633 *processed = raw64 * scale_val;
634 *processed += div_s64(raw64 * (s64)scale_val2 * scale,
635 1000000000LL);
636 break;
637 case IIO_VAL_FRACTIONAL:
638 *processed = div_s64(raw64 * (s64)scale_val * scale,
639 scale_val2);
640 break;
641 case IIO_VAL_FRACTIONAL_LOG2:
642 *processed = (raw64 * (s64)scale_val * scale) >> scale_val2;
643 break;
644 default:
645 return -EINVAL;
646 }
647
648 return 0;
649 }
650
iio_convert_raw_to_processed(struct iio_channel * chan,int raw,int * processed,unsigned int scale)651 int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
652 int *processed, unsigned int scale)
653 {
654 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
655 int ret;
656
657 mutex_lock(&iio_dev_opaque->info_exist_lock);
658 if (chan->indio_dev->info == NULL) {
659 ret = -ENODEV;
660 goto err_unlock;
661 }
662
663 ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
664 scale);
665 err_unlock:
666 mutex_unlock(&iio_dev_opaque->info_exist_lock);
667
668 return ret;
669 }
670 EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
671
iio_read_channel_attribute(struct iio_channel * chan,int * val,int * val2,enum iio_chan_info_enum attribute)672 int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
673 enum iio_chan_info_enum attribute)
674 {
675 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
676 int ret;
677
678 mutex_lock(&iio_dev_opaque->info_exist_lock);
679 if (chan->indio_dev->info == NULL) {
680 ret = -ENODEV;
681 goto err_unlock;
682 }
683
684 ret = iio_channel_read(chan, val, val2, attribute);
685 err_unlock:
686 mutex_unlock(&iio_dev_opaque->info_exist_lock);
687
688 return ret;
689 }
690 EXPORT_SYMBOL_GPL(iio_read_channel_attribute);
691
iio_read_channel_offset(struct iio_channel * chan,int * val,int * val2)692 int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2)
693 {
694 return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_OFFSET);
695 }
696 EXPORT_SYMBOL_GPL(iio_read_channel_offset);
697
iio_read_channel_processed_scale(struct iio_channel * chan,int * val,unsigned int scale)698 int iio_read_channel_processed_scale(struct iio_channel *chan, int *val,
699 unsigned int scale)
700 {
701 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
702 int ret;
703
704 mutex_lock(&iio_dev_opaque->info_exist_lock);
705 if (chan->indio_dev->info == NULL) {
706 ret = -ENODEV;
707 goto err_unlock;
708 }
709
710 if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) {
711 ret = iio_channel_read(chan, val, NULL,
712 IIO_CHAN_INFO_PROCESSED);
713 if (ret < 0)
714 goto err_unlock;
715 *val *= scale;
716 } else {
717 ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
718 if (ret < 0)
719 goto err_unlock;
720 ret = iio_convert_raw_to_processed_unlocked(chan, *val, val,
721 scale);
722 }
723
724 err_unlock:
725 mutex_unlock(&iio_dev_opaque->info_exist_lock);
726
727 return ret;
728 }
729 EXPORT_SYMBOL_GPL(iio_read_channel_processed_scale);
730
iio_read_channel_processed(struct iio_channel * chan,int * val)731 int iio_read_channel_processed(struct iio_channel *chan, int *val)
732 {
733 /* This is just a special case with scale factor 1 */
734 return iio_read_channel_processed_scale(chan, val, 1);
735 }
736 EXPORT_SYMBOL_GPL(iio_read_channel_processed);
737
iio_read_channel_scale(struct iio_channel * chan,int * val,int * val2)738 int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
739 {
740 return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_SCALE);
741 }
742 EXPORT_SYMBOL_GPL(iio_read_channel_scale);
743
iio_channel_read_avail(struct iio_channel * chan,const int ** vals,int * type,int * length,enum iio_chan_info_enum info)744 static int iio_channel_read_avail(struct iio_channel *chan,
745 const int **vals, int *type, int *length,
746 enum iio_chan_info_enum info)
747 {
748 if (!iio_channel_has_available(chan->channel, info))
749 return -EINVAL;
750
751 return chan->indio_dev->info->read_avail(chan->indio_dev, chan->channel,
752 vals, type, length, info);
753 }
754
iio_read_avail_channel_attribute(struct iio_channel * chan,const int ** vals,int * type,int * length,enum iio_chan_info_enum attribute)755 int iio_read_avail_channel_attribute(struct iio_channel *chan,
756 const int **vals, int *type, int *length,
757 enum iio_chan_info_enum attribute)
758 {
759 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
760 int ret;
761
762 mutex_lock(&iio_dev_opaque->info_exist_lock);
763 if (!chan->indio_dev->info) {
764 ret = -ENODEV;
765 goto err_unlock;
766 }
767
768 ret = iio_channel_read_avail(chan, vals, type, length, attribute);
769 err_unlock:
770 mutex_unlock(&iio_dev_opaque->info_exist_lock);
771
772 return ret;
773 }
774 EXPORT_SYMBOL_GPL(iio_read_avail_channel_attribute);
775
iio_read_avail_channel_raw(struct iio_channel * chan,const int ** vals,int * length)776 int iio_read_avail_channel_raw(struct iio_channel *chan,
777 const int **vals, int *length)
778 {
779 int ret;
780 int type;
781
782 ret = iio_read_avail_channel_attribute(chan, vals, &type, length,
783 IIO_CHAN_INFO_RAW);
784
785 if (ret >= 0 && type != IIO_VAL_INT)
786 /* raw values are assumed to be IIO_VAL_INT */
787 ret = -EINVAL;
788
789 return ret;
790 }
791 EXPORT_SYMBOL_GPL(iio_read_avail_channel_raw);
792
iio_channel_read_max(struct iio_channel * chan,int * val,int * val2,int * type,enum iio_chan_info_enum info)793 static int iio_channel_read_max(struct iio_channel *chan,
794 int *val, int *val2, int *type,
795 enum iio_chan_info_enum info)
796 {
797 int unused;
798 const int *vals;
799 int length;
800 int ret;
801
802 if (!val2)
803 val2 = &unused;
804
805 ret = iio_channel_read_avail(chan, &vals, type, &length, info);
806 switch (ret) {
807 case IIO_AVAIL_RANGE:
808 switch (*type) {
809 case IIO_VAL_INT:
810 *val = vals[2];
811 break;
812 default:
813 *val = vals[4];
814 *val2 = vals[5];
815 }
816 return 0;
817
818 case IIO_AVAIL_LIST:
819 if (length <= 0)
820 return -EINVAL;
821 switch (*type) {
822 case IIO_VAL_INT:
823 *val = vals[--length];
824 while (length) {
825 if (vals[--length] > *val)
826 *val = vals[length];
827 }
828 break;
829 default:
830 /* FIXME: learn about max for other iio values */
831 return -EINVAL;
832 }
833 return 0;
834
835 default:
836 return ret;
837 }
838 }
839
iio_read_max_channel_raw(struct iio_channel * chan,int * val)840 int iio_read_max_channel_raw(struct iio_channel *chan, int *val)
841 {
842 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
843 int ret;
844 int type;
845
846 mutex_lock(&iio_dev_opaque->info_exist_lock);
847 if (!chan->indio_dev->info) {
848 ret = -ENODEV;
849 goto err_unlock;
850 }
851
852 ret = iio_channel_read_max(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
853 err_unlock:
854 mutex_unlock(&iio_dev_opaque->info_exist_lock);
855
856 return ret;
857 }
858 EXPORT_SYMBOL_GPL(iio_read_max_channel_raw);
859
iio_get_channel_type(struct iio_channel * chan,enum iio_chan_type * type)860 int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
861 {
862 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
863 int ret = 0;
864 /* Need to verify underlying driver has not gone away */
865
866 mutex_lock(&iio_dev_opaque->info_exist_lock);
867 if (chan->indio_dev->info == NULL) {
868 ret = -ENODEV;
869 goto err_unlock;
870 }
871
872 *type = chan->channel->type;
873 err_unlock:
874 mutex_unlock(&iio_dev_opaque->info_exist_lock);
875
876 return ret;
877 }
878 EXPORT_SYMBOL_GPL(iio_get_channel_type);
879
iio_channel_write(struct iio_channel * chan,int val,int val2,enum iio_chan_info_enum info)880 static int iio_channel_write(struct iio_channel *chan, int val, int val2,
881 enum iio_chan_info_enum info)
882 {
883 return chan->indio_dev->info->write_raw(chan->indio_dev,
884 chan->channel, val, val2, info);
885 }
886
iio_write_channel_attribute(struct iio_channel * chan,int val,int val2,enum iio_chan_info_enum attribute)887 int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
888 enum iio_chan_info_enum attribute)
889 {
890 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
891 int ret;
892
893 mutex_lock(&iio_dev_opaque->info_exist_lock);
894 if (chan->indio_dev->info == NULL) {
895 ret = -ENODEV;
896 goto err_unlock;
897 }
898
899 ret = iio_channel_write(chan, val, val2, attribute);
900 err_unlock:
901 mutex_unlock(&iio_dev_opaque->info_exist_lock);
902
903 return ret;
904 }
905 EXPORT_SYMBOL_GPL(iio_write_channel_attribute);
906
iio_write_channel_raw(struct iio_channel * chan,int val)907 int iio_write_channel_raw(struct iio_channel *chan, int val)
908 {
909 return iio_write_channel_attribute(chan, val, 0, IIO_CHAN_INFO_RAW);
910 }
911 EXPORT_SYMBOL_GPL(iio_write_channel_raw);
912
iio_get_channel_ext_info_count(struct iio_channel * chan)913 unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)
914 {
915 const struct iio_chan_spec_ext_info *ext_info;
916 unsigned int i = 0;
917
918 if (!chan->channel->ext_info)
919 return i;
920
921 for (ext_info = chan->channel->ext_info; ext_info->name; ext_info++)
922 ++i;
923
924 return i;
925 }
926 EXPORT_SYMBOL_GPL(iio_get_channel_ext_info_count);
927
iio_lookup_ext_info(const struct iio_channel * chan,const char * attr)928 static const struct iio_chan_spec_ext_info *iio_lookup_ext_info(
929 const struct iio_channel *chan,
930 const char *attr)
931 {
932 const struct iio_chan_spec_ext_info *ext_info;
933
934 if (!chan->channel->ext_info)
935 return NULL;
936
937 for (ext_info = chan->channel->ext_info; ext_info->name; ++ext_info) {
938 if (!strcmp(attr, ext_info->name))
939 return ext_info;
940 }
941
942 return NULL;
943 }
944
iio_read_channel_ext_info(struct iio_channel * chan,const char * attr,char * buf)945 ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
946 const char *attr, char *buf)
947 {
948 const struct iio_chan_spec_ext_info *ext_info;
949
950 ext_info = iio_lookup_ext_info(chan, attr);
951 if (!ext_info)
952 return -EINVAL;
953
954 return ext_info->read(chan->indio_dev, ext_info->private,
955 chan->channel, buf);
956 }
957 EXPORT_SYMBOL_GPL(iio_read_channel_ext_info);
958
iio_write_channel_ext_info(struct iio_channel * chan,const char * attr,const char * buf,size_t len)959 ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
960 const char *buf, size_t len)
961 {
962 const struct iio_chan_spec_ext_info *ext_info;
963
964 ext_info = iio_lookup_ext_info(chan, attr);
965 if (!ext_info)
966 return -EINVAL;
967
968 return ext_info->write(chan->indio_dev, ext_info->private,
969 chan->channel, buf, len);
970 }
971 EXPORT_SYMBOL_GPL(iio_write_channel_ext_info);
972