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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/cleanup.h>
7#include <linux/err.h>
8#include <linux/export.h>
9#include <linux/minmax.h>
10#include <linux/mutex.h>
11#include <linux/property.h>
12#include <linux/slab.h>
13
14#include <linux/iio/iio.h>
15#include <linux/iio/iio-opaque.h>
16#include "iio_core.h"
17#include <linux/iio/machine.h>
18#include <linux/iio/driver.h>
19#include <linux/iio/consumer.h>
20
21struct iio_map_internal {
22 struct iio_dev *indio_dev;
23 const struct iio_map *map;
24 struct list_head l;
25};
26
27static LIST_HEAD(iio_map_list);
28static DEFINE_MUTEX(iio_map_list_lock);
29
30static int iio_map_array_unregister_locked(struct iio_dev *indio_dev)
31{
32 int ret = -ENODEV;
33 struct iio_map_internal *mapi, *next;
34
35 list_for_each_entry_safe(mapi, next, &iio_map_list, l) {
36 if (indio_dev == mapi->indio_dev) {
37 list_del(&mapi->l);
38 kfree(mapi);
39 ret = 0;
40 }
41 }
42 return ret;
43}
44
45int iio_map_array_register(struct iio_dev *indio_dev, const struct iio_map *maps)
46{
47 struct iio_map_internal *mapi;
48 int i = 0;
49 int ret;
50
51 if (!maps)
52 return 0;
53
54 guard(mutex)(&iio_map_list_lock);
55 while (maps[i].consumer_dev_name) {
56 mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
57 if (!mapi) {
58 ret = -ENOMEM;
59 goto error_ret;
60 }
61 mapi->map = &maps[i];
62 mapi->indio_dev = indio_dev;
63 list_add_tail(&mapi->l, &iio_map_list);
64 i++;
65 }
66
67 return 0;
68error_ret:
69 iio_map_array_unregister_locked(indio_dev);
70 return ret;
71}
72EXPORT_SYMBOL_GPL(iio_map_array_register);
73
74/*
75 * Remove all map entries associated with the given iio device
76 */
77int iio_map_array_unregister(struct iio_dev *indio_dev)
78{
79 guard(mutex)(&iio_map_list_lock);
80 return iio_map_array_unregister_locked(indio_dev);
81}
82EXPORT_SYMBOL_GPL(iio_map_array_unregister);
83
84static void iio_map_array_unregister_cb(void *indio_dev)
85{
86 iio_map_array_unregister(indio_dev);
87}
88
89int devm_iio_map_array_register(struct device *dev, struct iio_dev *indio_dev,
90 const struct iio_map *maps)
91{
92 int ret;
93
94 ret = iio_map_array_register(indio_dev, maps);
95 if (ret)
96 return ret;
97
98 return devm_add_action_or_reset(dev, iio_map_array_unregister_cb, indio_dev);
99}
100EXPORT_SYMBOL_GPL(devm_iio_map_array_register);
101
102static const struct iio_chan_spec
103*iio_chan_spec_from_name(const struct iio_dev *indio_dev, const char *name)
104{
105 int i;
106 const struct iio_chan_spec *chan = NULL;
107
108 for (i = 0; i < indio_dev->num_channels; i++)
109 if (indio_dev->channels[i].datasheet_name &&
110 strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
111 chan = &indio_dev->channels[i];
112 break;
113 }
114 return chan;
115}
116
117/**
118 * __fwnode_iio_simple_xlate - translate iiospec to the IIO channel index
119 * @indio_dev: pointer to the iio_dev structure
120 * @iiospec: IIO specifier as found in the device tree
121 *
122 * This is simple translation function, suitable for the most 1:1 mapped
123 * channels in IIO chips. This function performs only one sanity check:
124 * whether IIO index is less than num_channels (that is specified in the
125 * iio_dev).
126 */
127static int __fwnode_iio_simple_xlate(struct iio_dev *indio_dev,
128 const struct fwnode_reference_args *iiospec)
129{
130 if (!iiospec->nargs)
131 return 0;
132
133 if (iiospec->args[0] >= indio_dev->num_channels) {
134 dev_err(&indio_dev->dev, "invalid channel index %llu\n",
135 iiospec->args[0]);
136 return -EINVAL;
137 }
138
139 return iiospec->args[0];
140}
141
142static int __fwnode_iio_channel_get(struct iio_channel *channel,
143 struct fwnode_handle *fwnode, int index)
144{
145 struct fwnode_reference_args iiospec;
146 struct device *idev;
147 struct iio_dev *indio_dev;
148 int err;
149
150 err = fwnode_property_get_reference_args(fwnode, "io-channels",
151 "#io-channel-cells", 0,
152 index, &iiospec);
153 if (err)
154 return err;
155
156 idev = bus_find_device_by_fwnode(&iio_bus_type, iiospec.fwnode);
157 if (!idev) {
158 fwnode_handle_put(iiospec.fwnode);
159 return -EPROBE_DEFER;
160 }
161
162 indio_dev = dev_to_iio_dev(idev);
163 channel->indio_dev = indio_dev;
164 if (indio_dev->info->fwnode_xlate)
165 index = indio_dev->info->fwnode_xlate(indio_dev, &iiospec);
166 else
167 index = __fwnode_iio_simple_xlate(indio_dev, &iiospec);
168 fwnode_handle_put(iiospec.fwnode);
169 if (index < 0)
170 goto err_put;
171 channel->channel = &indio_dev->channels[index];
172
173 return 0;
174
175err_put:
176 iio_device_put(indio_dev);
177 return index;
178}
179
180static struct iio_channel *fwnode_iio_channel_get(struct fwnode_handle *fwnode,
181 int index)
182{
183 int err;
184
185 if (index < 0)
186 return ERR_PTR(-EINVAL);
187
188 struct iio_channel *channel __free(kfree) =
189 kzalloc(sizeof(*channel), GFP_KERNEL);
190 if (!channel)
191 return ERR_PTR(-ENOMEM);
192
193 err = __fwnode_iio_channel_get(channel, fwnode, index);
194 if (err)
195 return ERR_PTR(err);
196
197 return_ptr(channel);
198}
199
200static struct iio_channel *
201__fwnode_iio_channel_get_by_name(struct fwnode_handle *fwnode, const char *name)
202{
203 struct iio_channel *chan;
204 int index = 0;
205
206 /*
207 * For named iio channels, first look up the name in the
208 * "io-channel-names" property. If it cannot be found, the
209 * index will be an error code, and fwnode_iio_channel_get()
210 * will fail.
211 */
212 if (name)
213 index = fwnode_property_match_string(fwnode, "io-channel-names",
214 name);
215
216 chan = fwnode_iio_channel_get(fwnode, index);
217 if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER)
218 return chan;
219 if (name) {
220 if (index >= 0) {
221 pr_err("ERROR: could not get IIO channel %pfw:%s(%i)\n",
222 fwnode, name, index);
223 /*
224 * In this case, we found 'name' in 'io-channel-names'
225 * but somehow we still fail so that we should not proceed
226 * with any other lookup. Hence, explicitly return -EINVAL
227 * (maybe not the better error code) so that the caller
228 * won't do a system lookup.
229 */
230 return ERR_PTR(-EINVAL);
231 }
232 /*
233 * If index < 0, then fwnode_property_get_reference_args() fails
234 * with -EINVAL or -ENOENT (ACPI case) which is expected. We
235 * should not proceed if we get any other error.
236 */
237 if (PTR_ERR(chan) != -EINVAL && PTR_ERR(chan) != -ENOENT)
238 return chan;
239 } else if (PTR_ERR(chan) != -ENOENT) {
240 /*
241 * if !name, then we should only proceed the lookup if
242 * fwnode_property_get_reference_args() returns -ENOENT.
243 */
244 return chan;
245 }
246
247 /* so we continue the lookup */
248 return ERR_PTR(-ENODEV);
249}
250
251struct iio_channel *fwnode_iio_channel_get_by_name(struct fwnode_handle *fwnode,
252 const char *name)
253{
254 struct fwnode_handle *parent;
255 struct iio_channel *chan;
256
257 /* Walk up the tree of devices looking for a matching iio channel */
258 chan = __fwnode_iio_channel_get_by_name(fwnode, name);
259 if (!IS_ERR(chan) || PTR_ERR(chan) != -ENODEV)
260 return chan;
261
262 /*
263 * No matching IIO channel found on this node.
264 * If the parent node has a "io-channel-ranges" property,
265 * then we can try one of its channels.
266 */
267 fwnode_for_each_parent_node(fwnode, parent) {
268 if (!fwnode_property_present(parent, "io-channel-ranges")) {
269 fwnode_handle_put(parent);
270 return ERR_PTR(-ENODEV);
271 }
272
273 chan = __fwnode_iio_channel_get_by_name(parent, name);
274 if (!IS_ERR(chan) || PTR_ERR(chan) != -ENODEV) {
275 fwnode_handle_put(parent);
276 return chan;
277 }
278 }
279
280 return ERR_PTR(-ENODEV);
281}
282EXPORT_SYMBOL_GPL(fwnode_iio_channel_get_by_name);
283
284static struct iio_channel *fwnode_iio_channel_get_all(struct device *dev)
285{
286 struct fwnode_handle *fwnode = dev_fwnode(dev);
287 int i, mapind, nummaps = 0;
288 int ret;
289
290 do {
291 ret = fwnode_property_get_reference_args(fwnode, "io-channels",
292 "#io-channel-cells", 0,
293 nummaps, NULL);
294 if (ret < 0)
295 break;
296 } while (++nummaps);
297
298 if (nummaps == 0)
299 return ERR_PTR(-ENODEV);
300
301 /* NULL terminated array to save passing size */
302 struct iio_channel *chans __free(kfree) =
303 kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
304 if (!chans)
305 return ERR_PTR(-ENOMEM);
306
307 /* Search for FW matches */
308 for (mapind = 0; mapind < nummaps; mapind++) {
309 ret = __fwnode_iio_channel_get(&chans[mapind], fwnode, mapind);
310 if (ret)
311 goto error_free_chans;
312 }
313 return_ptr(chans);
314
315error_free_chans:
316 for (i = 0; i < mapind; i++)
317 iio_device_put(chans[i].indio_dev);
318 return ERR_PTR(ret);
319}
320
321static struct iio_channel *iio_channel_get_sys(const char *name,
322 const char *channel_name)
323{
324 struct iio_map_internal *c_i = NULL, *c = NULL;
325 int err;
326
327 if (!(name || channel_name))
328 return ERR_PTR(-ENODEV);
329
330 /* first find matching entry the channel map */
331 scoped_guard(mutex, &iio_map_list_lock) {
332 list_for_each_entry(c_i, &iio_map_list, l) {
333 if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) ||
334 (channel_name &&
335 strcmp(channel_name, c_i->map->consumer_channel) != 0))
336 continue;
337 c = c_i;
338 iio_device_get(c->indio_dev);
339 break;
340 }
341 }
342 if (!c)
343 return ERR_PTR(-ENODEV);
344
345 struct iio_channel *channel __free(kfree) =
346 kzalloc(sizeof(*channel), GFP_KERNEL);
347 if (!channel) {
348 err = -ENOMEM;
349 goto error_no_mem;
350 }
351
352 channel->indio_dev = c->indio_dev;
353
354 if (c->map->adc_channel_label) {
355 channel->channel =
356 iio_chan_spec_from_name(channel->indio_dev,
357 c->map->adc_channel_label);
358
359 if (!channel->channel) {
360 err = -EINVAL;
361 goto error_no_mem;
362 }
363 }
364
365 return_ptr(channel);
366
367error_no_mem:
368 iio_device_put(c->indio_dev);
369 return ERR_PTR(err);
370}
371
372struct iio_channel *iio_channel_get(struct device *dev,
373 const char *channel_name)
374{
375 const char *name = dev ? dev_name(dev) : NULL;
376 struct iio_channel *channel;
377
378 if (dev) {
379 channel = fwnode_iio_channel_get_by_name(dev_fwnode(dev),
380 channel_name);
381 if (!IS_ERR(channel) || PTR_ERR(channel) != -ENODEV)
382 return channel;
383 }
384
385 return iio_channel_get_sys(name, channel_name);
386}
387EXPORT_SYMBOL_GPL(iio_channel_get);
388
389void iio_channel_release(struct iio_channel *channel)
390{
391 if (!channel)
392 return;
393 iio_device_put(channel->indio_dev);
394 kfree(channel);
395}
396EXPORT_SYMBOL_GPL(iio_channel_release);
397
398static void devm_iio_channel_free(void *iio_channel)
399{
400 iio_channel_release(iio_channel);
401}
402
403struct iio_channel *devm_iio_channel_get(struct device *dev,
404 const char *channel_name)
405{
406 struct iio_channel *channel;
407 int ret;
408
409 channel = iio_channel_get(dev, channel_name);
410 if (IS_ERR(channel))
411 return channel;
412
413 ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
414 if (ret)
415 return ERR_PTR(ret);
416
417 return channel;
418}
419EXPORT_SYMBOL_GPL(devm_iio_channel_get);
420
421struct iio_channel *devm_fwnode_iio_channel_get_by_name(struct device *dev,
422 struct fwnode_handle *fwnode,
423 const char *channel_name)
424{
425 struct iio_channel *channel;
426 int ret;
427
428 channel = fwnode_iio_channel_get_by_name(fwnode, channel_name);
429 if (IS_ERR(channel))
430 return channel;
431
432 ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
433 if (ret)
434 return ERR_PTR(ret);
435
436 return channel;
437}
438EXPORT_SYMBOL_GPL(devm_fwnode_iio_channel_get_by_name);
439
440struct iio_channel *iio_channel_get_all(struct device *dev)
441{
442 const char *name;
443 struct iio_map_internal *c = NULL;
444 struct iio_channel *fw_chans;
445 int nummaps = 0;
446 int mapind = 0;
447 int i, ret;
448
449 if (!dev)
450 return ERR_PTR(-EINVAL);
451
452 fw_chans = fwnode_iio_channel_get_all(dev);
453 /*
454 * We only want to carry on if the error is -ENODEV. Anything else
455 * should be reported up the stack.
456 */
457 if (!IS_ERR(fw_chans) || PTR_ERR(fw_chans) != -ENODEV)
458 return fw_chans;
459
460 name = dev_name(dev);
461
462 guard(mutex)(&iio_map_list_lock);
463 /* first count the matching maps */
464 list_for_each_entry(c, &iio_map_list, l)
465 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
466 continue;
467 else
468 nummaps++;
469
470 if (nummaps == 0)
471 return ERR_PTR(-ENODEV);
472
473 /* NULL terminated array to save passing size */
474 struct iio_channel *chans __free(kfree) =
475 kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
476 if (!chans)
477 return ERR_PTR(-ENOMEM);
478
479 /* for each map fill in the chans element */
480 list_for_each_entry(c, &iio_map_list, l) {
481 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
482 continue;
483 chans[mapind].indio_dev = c->indio_dev;
484 chans[mapind].data = c->map->consumer_data;
485 chans[mapind].channel =
486 iio_chan_spec_from_name(chans[mapind].indio_dev,
487 c->map->adc_channel_label);
488 if (!chans[mapind].channel) {
489 ret = -EINVAL;
490 goto error_free_chans;
491 }
492 iio_device_get(chans[mapind].indio_dev);
493 mapind++;
494 }
495 if (mapind == 0) {
496 ret = -ENODEV;
497 goto error_free_chans;
498 }
499
500 return_ptr(chans);
501
502error_free_chans:
503 for (i = 0; i < mapind; i++)
504 iio_device_put(chans[i].indio_dev);
505 return ERR_PTR(ret);
506}
507EXPORT_SYMBOL_GPL(iio_channel_get_all);
508
509void iio_channel_release_all(struct iio_channel *channels)
510{
511 struct iio_channel *chan = &channels[0];
512
513 while (chan->indio_dev) {
514 iio_device_put(chan->indio_dev);
515 chan++;
516 }
517 kfree(channels);
518}
519EXPORT_SYMBOL_GPL(iio_channel_release_all);
520
521static void devm_iio_channel_free_all(void *iio_channels)
522{
523 iio_channel_release_all(iio_channels);
524}
525
526struct iio_channel *devm_iio_channel_get_all(struct device *dev)
527{
528 struct iio_channel *channels;
529 int ret;
530
531 channels = iio_channel_get_all(dev);
532 if (IS_ERR(channels))
533 return channels;
534
535 ret = devm_add_action_or_reset(dev, devm_iio_channel_free_all,
536 channels);
537 if (ret)
538 return ERR_PTR(ret);
539
540 return channels;
541}
542EXPORT_SYMBOL_GPL(devm_iio_channel_get_all);
543
544static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
545 enum iio_chan_info_enum info)
546{
547 const struct iio_info *iio_info = chan->indio_dev->info;
548 int unused;
549 int vals[INDIO_MAX_RAW_ELEMENTS];
550 int ret;
551 int val_len = 2;
552
553 if (!val2)
554 val2 = &unused;
555
556 if (!iio_channel_has_info(chan->channel, info))
557 return -EINVAL;
558
559 if (iio_info->read_raw_multi) {
560 ret = iio_info->read_raw_multi(chan->indio_dev,
561 chan->channel,
562 INDIO_MAX_RAW_ELEMENTS,
563 vals, &val_len, info);
564 *val = vals[0];
565 *val2 = vals[1];
566 } else if (iio_info->read_raw) {
567 ret = iio_info->read_raw(chan->indio_dev,
568 chan->channel, val, val2, info);
569 } else {
570 return -EINVAL;
571 }
572
573 return ret;
574}
575
576int iio_read_channel_raw(struct iio_channel *chan, int *val)
577{
578 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
579
580 guard(mutex)(&iio_dev_opaque->info_exist_lock);
581 if (!chan->indio_dev->info)
582 return -ENODEV;
583
584 return iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
585}
586EXPORT_SYMBOL_GPL(iio_read_channel_raw);
587
588int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
589{
590 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
591
592 guard(mutex)(&iio_dev_opaque->info_exist_lock);
593 if (!chan->indio_dev->info)
594 return -ENODEV;
595
596 return iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
597}
598EXPORT_SYMBOL_GPL(iio_read_channel_average_raw);
599
600static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
601 int raw, int *processed,
602 unsigned int scale)
603{
604 int scale_type, scale_val, scale_val2;
605 int offset_type, offset_val, offset_val2;
606 s64 raw64 = raw;
607
608 offset_type = iio_channel_read(chan, &offset_val, &offset_val2,
609 IIO_CHAN_INFO_OFFSET);
610 if (offset_type >= 0) {
611 switch (offset_type) {
612 case IIO_VAL_INT:
613 break;
614 case IIO_VAL_INT_PLUS_MICRO:
615 case IIO_VAL_INT_PLUS_NANO:
616 /*
617 * Both IIO_VAL_INT_PLUS_MICRO and IIO_VAL_INT_PLUS_NANO
618 * implicitely truncate the offset to it's integer form.
619 */
620 break;
621 case IIO_VAL_FRACTIONAL:
622 offset_val /= offset_val2;
623 break;
624 case IIO_VAL_FRACTIONAL_LOG2:
625 offset_val >>= offset_val2;
626 break;
627 default:
628 return -EINVAL;
629 }
630
631 raw64 += offset_val;
632 }
633
634 scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
635 IIO_CHAN_INFO_SCALE);
636 if (scale_type < 0) {
637 /*
638 * If no channel scaling is available apply consumer scale to
639 * raw value and return.
640 */
641 *processed = raw * scale;
642 return 0;
643 }
644
645 switch (scale_type) {
646 case IIO_VAL_INT:
647 *processed = raw64 * scale_val * scale;
648 break;
649 case IIO_VAL_INT_PLUS_MICRO:
650 if (scale_val2 < 0)
651 *processed = -raw64 * scale_val * scale;
652 else
653 *processed = raw64 * scale_val * scale;
654 *processed += div_s64(raw64 * (s64)scale_val2 * scale,
655 1000000LL);
656 break;
657 case IIO_VAL_INT_PLUS_NANO:
658 if (scale_val2 < 0)
659 *processed = -raw64 * scale_val * scale;
660 else
661 *processed = raw64 * scale_val * scale;
662 *processed += div_s64(raw64 * (s64)scale_val2 * scale,
663 1000000000LL);
664 break;
665 case IIO_VAL_FRACTIONAL:
666 *processed = div_s64(raw64 * (s64)scale_val * scale,
667 scale_val2);
668 break;
669 case IIO_VAL_FRACTIONAL_LOG2:
670 *processed = (raw64 * (s64)scale_val * scale) >> scale_val2;
671 break;
672 default:
673 return -EINVAL;
674 }
675
676 return 0;
677}
678
679int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
680 int *processed, unsigned int scale)
681{
682 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
683
684 guard(mutex)(&iio_dev_opaque->info_exist_lock);
685 if (!chan->indio_dev->info)
686 return -ENODEV;
687
688 return iio_convert_raw_to_processed_unlocked(chan, raw, processed,
689 scale);
690}
691EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
692
693int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
694 enum iio_chan_info_enum attribute)
695{
696 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
697
698 guard(mutex)(&iio_dev_opaque->info_exist_lock);
699 if (!chan->indio_dev->info)
700 return -ENODEV;
701
702 return iio_channel_read(chan, val, val2, attribute);
703}
704EXPORT_SYMBOL_GPL(iio_read_channel_attribute);
705
706int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2)
707{
708 return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_OFFSET);
709}
710EXPORT_SYMBOL_GPL(iio_read_channel_offset);
711
712int iio_read_channel_processed_scale(struct iio_channel *chan, int *val,
713 unsigned int scale)
714{
715 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
716 int ret;
717
718 guard(mutex)(&iio_dev_opaque->info_exist_lock);
719 if (!chan->indio_dev->info)
720 return -ENODEV;
721
722 if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) {
723 ret = iio_channel_read(chan, val, NULL,
724 IIO_CHAN_INFO_PROCESSED);
725 if (ret < 0)
726 return ret;
727 *val *= scale;
728
729 return ret;
730 } else {
731 ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
732 if (ret < 0)
733 return ret;
734
735 return iio_convert_raw_to_processed_unlocked(chan, *val, val,
736 scale);
737 }
738}
739EXPORT_SYMBOL_GPL(iio_read_channel_processed_scale);
740
741int iio_read_channel_processed(struct iio_channel *chan, int *val)
742{
743 /* This is just a special case with scale factor 1 */
744 return iio_read_channel_processed_scale(chan, val, 1);
745}
746EXPORT_SYMBOL_GPL(iio_read_channel_processed);
747
748int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
749{
750 return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_SCALE);
751}
752EXPORT_SYMBOL_GPL(iio_read_channel_scale);
753
754static int iio_channel_read_avail(struct iio_channel *chan,
755 const int **vals, int *type, int *length,
756 enum iio_chan_info_enum info)
757{
758 const struct iio_info *iio_info = chan->indio_dev->info;
759
760 if (!iio_channel_has_available(chan->channel, info))
761 return -EINVAL;
762
763 if (iio_info->read_avail)
764 return iio_info->read_avail(chan->indio_dev, chan->channel,
765 vals, type, length, info);
766 return -EINVAL;
767}
768
769int iio_read_avail_channel_attribute(struct iio_channel *chan,
770 const int **vals, int *type, int *length,
771 enum iio_chan_info_enum attribute)
772{
773 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
774
775 guard(mutex)(&iio_dev_opaque->info_exist_lock);
776 if (!chan->indio_dev->info)
777 return -ENODEV;
778
779 return iio_channel_read_avail(chan, vals, type, length, attribute);
780}
781EXPORT_SYMBOL_GPL(iio_read_avail_channel_attribute);
782
783int iio_read_avail_channel_raw(struct iio_channel *chan,
784 const int **vals, int *length)
785{
786 int ret;
787 int type;
788
789 ret = iio_read_avail_channel_attribute(chan, vals, &type, length,
790 IIO_CHAN_INFO_RAW);
791
792 if (ret >= 0 && type != IIO_VAL_INT)
793 /* raw values are assumed to be IIO_VAL_INT */
794 ret = -EINVAL;
795
796 return ret;
797}
798EXPORT_SYMBOL_GPL(iio_read_avail_channel_raw);
799
800static int iio_channel_read_max(struct iio_channel *chan,
801 int *val, int *val2, int *type,
802 enum iio_chan_info_enum info)
803{
804 const int *vals;
805 int length;
806 int ret;
807
808 ret = iio_channel_read_avail(chan, &vals, type, &length, info);
809 if (ret < 0)
810 return ret;
811
812 switch (ret) {
813 case IIO_AVAIL_RANGE:
814 switch (*type) {
815 case IIO_VAL_INT:
816 *val = vals[2];
817 break;
818 default:
819 *val = vals[4];
820 if (val2)
821 *val2 = vals[5];
822 }
823 return 0;
824
825 case IIO_AVAIL_LIST:
826 if (length <= 0)
827 return -EINVAL;
828 switch (*type) {
829 case IIO_VAL_INT:
830 *val = max_array(vals, length);
831 break;
832 default:
833 /* TODO: learn about max for other iio values */
834 return -EINVAL;
835 }
836 return 0;
837
838 default:
839 return -EINVAL;
840 }
841}
842
843int iio_read_max_channel_raw(struct iio_channel *chan, int *val)
844{
845 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
846 int type;
847
848 guard(mutex)(&iio_dev_opaque->info_exist_lock);
849 if (!chan->indio_dev->info)
850 return -ENODEV;
851
852 return iio_channel_read_max(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
853}
854EXPORT_SYMBOL_GPL(iio_read_max_channel_raw);
855
856static int iio_channel_read_min(struct iio_channel *chan,
857 int *val, int *val2, int *type,
858 enum iio_chan_info_enum info)
859{
860 const int *vals;
861 int length;
862 int ret;
863
864 ret = iio_channel_read_avail(chan, &vals, type, &length, info);
865 if (ret < 0)
866 return ret;
867
868 switch (ret) {
869 case IIO_AVAIL_RANGE:
870 switch (*type) {
871 case IIO_VAL_INT:
872 *val = vals[0];
873 break;
874 default:
875 *val = vals[0];
876 if (val2)
877 *val2 = vals[1];
878 }
879 return 0;
880
881 case IIO_AVAIL_LIST:
882 if (length <= 0)
883 return -EINVAL;
884 switch (*type) {
885 case IIO_VAL_INT:
886 *val = min_array(vals, length);
887 break;
888 default:
889 /* TODO: learn about min for other iio values */
890 return -EINVAL;
891 }
892 return 0;
893
894 default:
895 return -EINVAL;
896 }
897}
898
899int iio_read_min_channel_raw(struct iio_channel *chan, int *val)
900{
901 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
902 int type;
903
904 guard(mutex)(&iio_dev_opaque->info_exist_lock);
905 if (!chan->indio_dev->info)
906 return -ENODEV;
907
908 return iio_channel_read_min(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
909}
910EXPORT_SYMBOL_GPL(iio_read_min_channel_raw);
911
912int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
913{
914 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
915
916 guard(mutex)(&iio_dev_opaque->info_exist_lock);
917 if (!chan->indio_dev->info)
918 return -ENODEV;
919
920 *type = chan->channel->type;
921
922 return 0;
923}
924EXPORT_SYMBOL_GPL(iio_get_channel_type);
925
926static int iio_channel_write(struct iio_channel *chan, int val, int val2,
927 enum iio_chan_info_enum info)
928{
929 const struct iio_info *iio_info = chan->indio_dev->info;
930
931 if (iio_info->write_raw)
932 return iio_info->write_raw(chan->indio_dev,
933 chan->channel, val, val2, info);
934 return -EINVAL;
935}
936
937int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
938 enum iio_chan_info_enum attribute)
939{
940 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
941
942 guard(mutex)(&iio_dev_opaque->info_exist_lock);
943 if (!chan->indio_dev->info)
944 return -ENODEV;
945
946 return iio_channel_write(chan, val, val2, attribute);
947}
948EXPORT_SYMBOL_GPL(iio_write_channel_attribute);
949
950int iio_write_channel_raw(struct iio_channel *chan, int val)
951{
952 return iio_write_channel_attribute(chan, val, 0, IIO_CHAN_INFO_RAW);
953}
954EXPORT_SYMBOL_GPL(iio_write_channel_raw);
955
956unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)
957{
958 const struct iio_chan_spec_ext_info *ext_info;
959 unsigned int i = 0;
960
961 if (!chan->channel->ext_info)
962 return i;
963
964 for (ext_info = chan->channel->ext_info; ext_info->name; ext_info++)
965 ++i;
966
967 return i;
968}
969EXPORT_SYMBOL_GPL(iio_get_channel_ext_info_count);
970
971static const struct iio_chan_spec_ext_info *
972iio_lookup_ext_info(const struct iio_channel *chan, const char *attr)
973{
974 const struct iio_chan_spec_ext_info *ext_info;
975
976 if (!chan->channel->ext_info)
977 return NULL;
978
979 for (ext_info = chan->channel->ext_info; ext_info->name; ++ext_info) {
980 if (!strcmp(attr, ext_info->name))
981 return ext_info;
982 }
983
984 return NULL;
985}
986
987ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
988 const char *attr, char *buf)
989{
990 const struct iio_chan_spec_ext_info *ext_info;
991
992 ext_info = iio_lookup_ext_info(chan, attr);
993 if (!ext_info)
994 return -EINVAL;
995
996 return ext_info->read(chan->indio_dev, ext_info->private,
997 chan->channel, buf);
998}
999EXPORT_SYMBOL_GPL(iio_read_channel_ext_info);
1000
1001ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
1002 const char *buf, size_t len)
1003{
1004 const struct iio_chan_spec_ext_info *ext_info;
1005
1006 ext_info = iio_lookup_ext_info(chan, attr);
1007 if (!ext_info)
1008 return -EINVAL;
1009
1010 return ext_info->write(chan->indio_dev, ext_info->private,
1011 chan->channel, buf, len);
1012}
1013EXPORT_SYMBOL_GPL(iio_write_channel_ext_info);
1014
1015ssize_t iio_read_channel_label(struct iio_channel *chan, char *buf)
1016{
1017 return do_iio_read_channel_label(chan->indio_dev, chan->channel, buf);
1018}
1019EXPORT_SYMBOL_GPL(iio_read_channel_label);
1/* The industrial I/O core in kernel channel mapping
2 *
3 * Copyright (c) 2011 Jonathan Cameron
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 */
9#include <linux/err.h>
10#include <linux/export.h>
11#include <linux/slab.h>
12#include <linux/mutex.h>
13
14#include <linux/iio/iio.h>
15#include "iio_core.h"
16#include <linux/iio/machine.h>
17#include <linux/iio/driver.h>
18#include <linux/iio/consumer.h>
19
20struct iio_map_internal {
21 struct iio_dev *indio_dev;
22 struct iio_map *map;
23 struct list_head l;
24};
25
26static LIST_HEAD(iio_map_list);
27static DEFINE_MUTEX(iio_map_list_lock);
28
29int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps)
30{
31 int i = 0, ret = 0;
32 struct iio_map_internal *mapi;
33
34 if (maps == NULL)
35 return 0;
36
37 mutex_lock(&iio_map_list_lock);
38 while (maps[i].consumer_dev_name != NULL) {
39 mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
40 if (mapi == NULL) {
41 ret = -ENOMEM;
42 goto error_ret;
43 }
44 mapi->map = &maps[i];
45 mapi->indio_dev = indio_dev;
46 list_add(&mapi->l, &iio_map_list);
47 i++;
48 }
49error_ret:
50 mutex_unlock(&iio_map_list_lock);
51
52 return ret;
53}
54EXPORT_SYMBOL_GPL(iio_map_array_register);
55
56
57/* Assumes the exact same array (e.g. memory locations)
58 * used at unregistration as used at registration rather than
59 * more complex checking of contents.
60 */
61int iio_map_array_unregister(struct iio_dev *indio_dev,
62 struct iio_map *maps)
63{
64 int i = 0, ret = 0;
65 bool found_it;
66 struct iio_map_internal *mapi;
67
68 if (maps == NULL)
69 return 0;
70
71 mutex_lock(&iio_map_list_lock);
72 while (maps[i].consumer_dev_name != NULL) {
73 found_it = false;
74 list_for_each_entry(mapi, &iio_map_list, l)
75 if (&maps[i] == mapi->map) {
76 list_del(&mapi->l);
77 kfree(mapi);
78 found_it = true;
79 break;
80 }
81 if (found_it == false) {
82 ret = -ENODEV;
83 goto error_ret;
84 }
85 i++;
86 }
87error_ret:
88 mutex_unlock(&iio_map_list_lock);
89
90 return ret;
91}
92EXPORT_SYMBOL_GPL(iio_map_array_unregister);
93
94static const struct iio_chan_spec
95*iio_chan_spec_from_name(const struct iio_dev *indio_dev,
96 const char *name)
97{
98 int i;
99 const struct iio_chan_spec *chan = NULL;
100
101 for (i = 0; i < indio_dev->num_channels; i++)
102 if (indio_dev->channels[i].datasheet_name &&
103 strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
104 chan = &indio_dev->channels[i];
105 break;
106 }
107 return chan;
108}
109
110
111struct iio_channel *iio_st_channel_get(const char *name,
112 const char *channel_name)
113{
114 struct iio_map_internal *c_i = NULL, *c = NULL;
115 struct iio_channel *channel;
116
117 if (name == NULL && channel_name == NULL)
118 return ERR_PTR(-ENODEV);
119
120 /* first find matching entry the channel map */
121 mutex_lock(&iio_map_list_lock);
122 list_for_each_entry(c_i, &iio_map_list, l) {
123 if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) ||
124 (channel_name &&
125 strcmp(channel_name, c_i->map->consumer_channel) != 0))
126 continue;
127 c = c_i;
128 get_device(&c->indio_dev->dev);
129 break;
130 }
131 mutex_unlock(&iio_map_list_lock);
132 if (c == NULL)
133 return ERR_PTR(-ENODEV);
134
135 channel = kmalloc(sizeof(*channel), GFP_KERNEL);
136 if (channel == NULL)
137 return ERR_PTR(-ENOMEM);
138
139 channel->indio_dev = c->indio_dev;
140
141 if (c->map->adc_channel_label)
142 channel->channel =
143 iio_chan_spec_from_name(channel->indio_dev,
144 c->map->adc_channel_label);
145
146 return channel;
147}
148EXPORT_SYMBOL_GPL(iio_st_channel_get);
149
150void iio_st_channel_release(struct iio_channel *channel)
151{
152 put_device(&channel->indio_dev->dev);
153 kfree(channel);
154}
155EXPORT_SYMBOL_GPL(iio_st_channel_release);
156
157struct iio_channel *iio_st_channel_get_all(const char *name)
158{
159 struct iio_channel *chans;
160 struct iio_map_internal *c = NULL;
161 int nummaps = 0;
162 int mapind = 0;
163 int i, ret;
164
165 if (name == NULL)
166 return ERR_PTR(-EINVAL);
167
168 mutex_lock(&iio_map_list_lock);
169 /* first count the matching maps */
170 list_for_each_entry(c, &iio_map_list, l)
171 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
172 continue;
173 else
174 nummaps++;
175
176 if (nummaps == 0) {
177 ret = -ENODEV;
178 goto error_ret;
179 }
180
181 /* NULL terminated array to save passing size */
182 chans = kzalloc(sizeof(*chans)*(nummaps + 1), GFP_KERNEL);
183 if (chans == NULL) {
184 ret = -ENOMEM;
185 goto error_ret;
186 }
187
188 /* for each map fill in the chans element */
189 list_for_each_entry(c, &iio_map_list, l) {
190 if (name && strcmp(name, c->map->consumer_dev_name) != 0)
191 continue;
192 chans[mapind].indio_dev = c->indio_dev;
193 chans[mapind].channel =
194 iio_chan_spec_from_name(chans[mapind].indio_dev,
195 c->map->adc_channel_label);
196 if (chans[mapind].channel == NULL) {
197 ret = -EINVAL;
198 put_device(&chans[mapind].indio_dev->dev);
199 goto error_free_chans;
200 }
201 get_device(&chans[mapind].indio_dev->dev);
202 mapind++;
203 }
204 mutex_unlock(&iio_map_list_lock);
205 if (mapind == 0) {
206 ret = -ENODEV;
207 goto error_free_chans;
208 }
209 return chans;
210
211error_free_chans:
212 for (i = 0; i < nummaps; i++)
213 if (chans[i].indio_dev)
214 put_device(&chans[i].indio_dev->dev);
215 kfree(chans);
216error_ret:
217 mutex_unlock(&iio_map_list_lock);
218
219 return ERR_PTR(ret);
220}
221EXPORT_SYMBOL_GPL(iio_st_channel_get_all);
222
223void iio_st_channel_release_all(struct iio_channel *channels)
224{
225 struct iio_channel *chan = &channels[0];
226
227 while (chan->indio_dev) {
228 put_device(&chan->indio_dev->dev);
229 chan++;
230 }
231 kfree(channels);
232}
233EXPORT_SYMBOL_GPL(iio_st_channel_release_all);
234
235int iio_st_read_channel_raw(struct iio_channel *chan, int *val)
236{
237 int val2, ret;
238
239 mutex_lock(&chan->indio_dev->info_exist_lock);
240 if (chan->indio_dev->info == NULL) {
241 ret = -ENODEV;
242 goto err_unlock;
243 }
244
245 ret = chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel,
246 val, &val2, 0);
247err_unlock:
248 mutex_unlock(&chan->indio_dev->info_exist_lock);
249
250 return ret;
251}
252EXPORT_SYMBOL_GPL(iio_st_read_channel_raw);
253
254int iio_st_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
255{
256 int ret;
257
258 mutex_lock(&chan->indio_dev->info_exist_lock);
259 if (chan->indio_dev->info == NULL) {
260 ret = -ENODEV;
261 goto err_unlock;
262 }
263
264 ret = chan->indio_dev->info->read_raw(chan->indio_dev,
265 chan->channel,
266 val, val2,
267 IIO_CHAN_INFO_SCALE);
268err_unlock:
269 mutex_unlock(&chan->indio_dev->info_exist_lock);
270
271 return ret;
272}
273EXPORT_SYMBOL_GPL(iio_st_read_channel_scale);
274
275int iio_st_get_channel_type(struct iio_channel *chan,
276 enum iio_chan_type *type)
277{
278 int ret = 0;
279 /* Need to verify underlying driver has not gone away */
280
281 mutex_lock(&chan->indio_dev->info_exist_lock);
282 if (chan->indio_dev->info == NULL) {
283 ret = -ENODEV;
284 goto err_unlock;
285 }
286
287 *type = chan->channel->type;
288err_unlock:
289 mutex_unlock(&chan->indio_dev->info_exist_lock);
290
291 return ret;
292}
293EXPORT_SYMBOL_GPL(iio_st_get_channel_type);