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12#include <linux/kernel.h>
13#include <linux/export.h>
14#include <linux/device.h>
15#include <linux/fs.h>
16#include <linux/cdev.h>
17#include <linux/slab.h>
18#include <linux/poll.h>
19#include <linux/sched/signal.h>
20
21#include <linux/iio/iio.h>
22#include "iio_core.h"
23#include <linux/iio/sysfs.h>
24#include <linux/iio/buffer.h>
25#include <linux/iio/buffer_impl.h>
26
27static const char * const iio_endian_prefix[] = {
28 [IIO_BE] = "be",
29 [IIO_LE] = "le",
30};
31
32static bool iio_buffer_is_active(struct iio_buffer *buf)
33{
34 return !list_empty(&buf->buffer_list);
35}
36
37static size_t iio_buffer_data_available(struct iio_buffer *buf)
38{
39 return buf->access->data_available(buf);
40}
41
42static int iio_buffer_flush_hwfifo(struct iio_dev *indio_dev,
43 struct iio_buffer *buf, size_t required)
44{
45 if (!indio_dev->info->hwfifo_flush_to_buffer)
46 return -ENODEV;
47
48 return indio_dev->info->hwfifo_flush_to_buffer(indio_dev, required);
49}
50
51static bool iio_buffer_ready(struct iio_dev *indio_dev, struct iio_buffer *buf,
52 size_t to_wait, int to_flush)
53{
54 size_t avail;
55 int flushed = 0;
56
57
58 if (!indio_dev->info)
59 return true;
60
61
62 if (!iio_buffer_is_active(buf)) {
63 to_wait = min_t(size_t, to_wait, 1);
64 to_flush = 0;
65 }
66
67 avail = iio_buffer_data_available(buf);
68
69 if (avail >= to_wait) {
70
71 if (!to_wait && avail < to_flush)
72 iio_buffer_flush_hwfifo(indio_dev, buf,
73 to_flush - avail);
74 return true;
75 }
76
77 if (to_flush)
78 flushed = iio_buffer_flush_hwfifo(indio_dev, buf,
79 to_wait - avail);
80 if (flushed <= 0)
81 return false;
82
83 if (avail + flushed >= to_wait)
84 return true;
85
86 return false;
87}
88
89
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95
96
97
98
99
100
101
102ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
103 size_t n, loff_t *f_ps)
104{
105 struct iio_dev *indio_dev = filp->private_data;
106 struct iio_buffer *rb = indio_dev->buffer;
107 DEFINE_WAIT_FUNC(wait, woken_wake_function);
108 size_t datum_size;
109 size_t to_wait;
110 int ret = 0;
111
112 if (!indio_dev->info)
113 return -ENODEV;
114
115 if (!rb || !rb->access->read_first_n)
116 return -EINVAL;
117
118 datum_size = rb->bytes_per_datum;
119
120
121
122
123
124 if (!datum_size)
125 return 0;
126
127 if (filp->f_flags & O_NONBLOCK)
128 to_wait = 0;
129 else
130 to_wait = min_t(size_t, n / datum_size, rb->watermark);
131
132 add_wait_queue(&rb->pollq, &wait);
133 do {
134 if (!indio_dev->info) {
135 ret = -ENODEV;
136 break;
137 }
138
139 if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) {
140 if (signal_pending(current)) {
141 ret = -ERESTARTSYS;
142 break;
143 }
144
145 wait_woken(&wait, TASK_INTERRUPTIBLE,
146 MAX_SCHEDULE_TIMEOUT);
147 continue;
148 }
149
150 ret = rb->access->read_first_n(rb, n, buf);
151 if (ret == 0 && (filp->f_flags & O_NONBLOCK))
152 ret = -EAGAIN;
153 } while (ret == 0);
154 remove_wait_queue(&rb->pollq, &wait);
155
156 return ret;
157}
158
159
160
161
162
163
164
165
166
167
168__poll_t iio_buffer_poll(struct file *filp,
169 struct poll_table_struct *wait)
170{
171 struct iio_dev *indio_dev = filp->private_data;
172 struct iio_buffer *rb = indio_dev->buffer;
173
174 if (!indio_dev->info || rb == NULL)
175 return 0;
176
177 poll_wait(filp, &rb->pollq, wait);
178 if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0))
179 return EPOLLIN | EPOLLRDNORM;
180 return 0;
181}
182
183
184
185
186
187
188
189
190void iio_buffer_wakeup_poll(struct iio_dev *indio_dev)
191{
192 if (!indio_dev->buffer)
193 return;
194
195 wake_up(&indio_dev->buffer->pollq);
196}
197
198void iio_buffer_init(struct iio_buffer *buffer)
199{
200 INIT_LIST_HEAD(&buffer->demux_list);
201 INIT_LIST_HEAD(&buffer->buffer_list);
202 init_waitqueue_head(&buffer->pollq);
203 kref_init(&buffer->ref);
204 if (!buffer->watermark)
205 buffer->watermark = 1;
206}
207EXPORT_SYMBOL(iio_buffer_init);
208
209
210
211
212
213
214void iio_buffer_set_attrs(struct iio_buffer *buffer,
215 const struct attribute **attrs)
216{
217 buffer->attrs = attrs;
218}
219EXPORT_SYMBOL_GPL(iio_buffer_set_attrs);
220
221static ssize_t iio_show_scan_index(struct device *dev,
222 struct device_attribute *attr,
223 char *buf)
224{
225 return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index);
226}
227
228static ssize_t iio_show_fixed_type(struct device *dev,
229 struct device_attribute *attr,
230 char *buf)
231{
232 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
233 u8 type = this_attr->c->scan_type.endianness;
234
235 if (type == IIO_CPU) {
236#ifdef __LITTLE_ENDIAN
237 type = IIO_LE;
238#else
239 type = IIO_BE;
240#endif
241 }
242 if (this_attr->c->scan_type.repeat > 1)
243 return sprintf(buf, "%s:%c%d/%dX%d>>%u\n",
244 iio_endian_prefix[type],
245 this_attr->c->scan_type.sign,
246 this_attr->c->scan_type.realbits,
247 this_attr->c->scan_type.storagebits,
248 this_attr->c->scan_type.repeat,
249 this_attr->c->scan_type.shift);
250 else
251 return sprintf(buf, "%s:%c%d/%d>>%u\n",
252 iio_endian_prefix[type],
253 this_attr->c->scan_type.sign,
254 this_attr->c->scan_type.realbits,
255 this_attr->c->scan_type.storagebits,
256 this_attr->c->scan_type.shift);
257}
258
259static ssize_t iio_scan_el_show(struct device *dev,
260 struct device_attribute *attr,
261 char *buf)
262{
263 int ret;
264 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
265
266
267 ret = !!test_bit(to_iio_dev_attr(attr)->address,
268 indio_dev->buffer->scan_mask);
269
270 return sprintf(buf, "%d\n", ret);
271}
272
273
274static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks,
275 unsigned int masklength,
276 const unsigned long *mask,
277 bool strict)
278{
279 if (bitmap_empty(mask, masklength))
280 return NULL;
281 while (*av_masks) {
282 if (strict) {
283 if (bitmap_equal(mask, av_masks, masklength))
284 return av_masks;
285 } else {
286 if (bitmap_subset(mask, av_masks, masklength))
287 return av_masks;
288 }
289 av_masks += BITS_TO_LONGS(masklength);
290 }
291 return NULL;
292}
293
294static bool iio_validate_scan_mask(struct iio_dev *indio_dev,
295 const unsigned long *mask)
296{
297 if (!indio_dev->setup_ops->validate_scan_mask)
298 return true;
299
300 return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask);
301}
302
303
304
305
306
307
308
309
310
311
312
313static int iio_scan_mask_set(struct iio_dev *indio_dev,
314 struct iio_buffer *buffer, int bit)
315{
316 const unsigned long *mask;
317 unsigned long *trialmask;
318
319 trialmask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
320 sizeof(*trialmask), GFP_KERNEL);
321 if (trialmask == NULL)
322 return -ENOMEM;
323 if (!indio_dev->masklength) {
324 WARN(1, "Trying to set scanmask prior to registering buffer\n");
325 goto err_invalid_mask;
326 }
327 bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
328 set_bit(bit, trialmask);
329
330 if (!iio_validate_scan_mask(indio_dev, trialmask))
331 goto err_invalid_mask;
332
333 if (indio_dev->available_scan_masks) {
334 mask = iio_scan_mask_match(indio_dev->available_scan_masks,
335 indio_dev->masklength,
336 trialmask, false);
337 if (!mask)
338 goto err_invalid_mask;
339 }
340 bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
341
342 bitmap_free(trialmask);
343
344 return 0;
345
346err_invalid_mask:
347 bitmap_free(trialmask);
348 return -EINVAL;
349}
350
351static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit)
352{
353 clear_bit(bit, buffer->scan_mask);
354 return 0;
355}
356
357static int iio_scan_mask_query(struct iio_dev *indio_dev,
358 struct iio_buffer *buffer, int bit)
359{
360 if (bit > indio_dev->masklength)
361 return -EINVAL;
362
363 if (!buffer->scan_mask)
364 return 0;
365
366
367 return !!test_bit(bit, buffer->scan_mask);
368};
369
370static ssize_t iio_scan_el_store(struct device *dev,
371 struct device_attribute *attr,
372 const char *buf,
373 size_t len)
374{
375 int ret;
376 bool state;
377 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
378 struct iio_buffer *buffer = indio_dev->buffer;
379 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
380
381 ret = strtobool(buf, &state);
382 if (ret < 0)
383 return ret;
384 mutex_lock(&indio_dev->mlock);
385 if (iio_buffer_is_active(indio_dev->buffer)) {
386 ret = -EBUSY;
387 goto error_ret;
388 }
389 ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address);
390 if (ret < 0)
391 goto error_ret;
392 if (!state && ret) {
393 ret = iio_scan_mask_clear(buffer, this_attr->address);
394 if (ret)
395 goto error_ret;
396 } else if (state && !ret) {
397 ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address);
398 if (ret)
399 goto error_ret;
400 }
401
402error_ret:
403 mutex_unlock(&indio_dev->mlock);
404
405 return ret < 0 ? ret : len;
406
407}
408
409static ssize_t iio_scan_el_ts_show(struct device *dev,
410 struct device_attribute *attr,
411 char *buf)
412{
413 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
414 return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp);
415}
416
417static ssize_t iio_scan_el_ts_store(struct device *dev,
418 struct device_attribute *attr,
419 const char *buf,
420 size_t len)
421{
422 int ret;
423 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
424 bool state;
425
426 ret = strtobool(buf, &state);
427 if (ret < 0)
428 return ret;
429
430 mutex_lock(&indio_dev->mlock);
431 if (iio_buffer_is_active(indio_dev->buffer)) {
432 ret = -EBUSY;
433 goto error_ret;
434 }
435 indio_dev->buffer->scan_timestamp = state;
436error_ret:
437 mutex_unlock(&indio_dev->mlock);
438
439 return ret ? ret : len;
440}
441
442static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
443 const struct iio_chan_spec *chan)
444{
445 int ret, attrcount = 0;
446 struct iio_buffer *buffer = indio_dev->buffer;
447
448 ret = __iio_add_chan_devattr("index",
449 chan,
450 &iio_show_scan_index,
451 NULL,
452 0,
453 IIO_SEPARATE,
454 &indio_dev->dev,
455 &buffer->scan_el_dev_attr_list);
456 if (ret)
457 return ret;
458 attrcount++;
459 ret = __iio_add_chan_devattr("type",
460 chan,
461 &iio_show_fixed_type,
462 NULL,
463 0,
464 0,
465 &indio_dev->dev,
466 &buffer->scan_el_dev_attr_list);
467 if (ret)
468 return ret;
469 attrcount++;
470 if (chan->type != IIO_TIMESTAMP)
471 ret = __iio_add_chan_devattr("en",
472 chan,
473 &iio_scan_el_show,
474 &iio_scan_el_store,
475 chan->scan_index,
476 0,
477 &indio_dev->dev,
478 &buffer->scan_el_dev_attr_list);
479 else
480 ret = __iio_add_chan_devattr("en",
481 chan,
482 &iio_scan_el_ts_show,
483 &iio_scan_el_ts_store,
484 chan->scan_index,
485 0,
486 &indio_dev->dev,
487 &buffer->scan_el_dev_attr_list);
488 if (ret)
489 return ret;
490 attrcount++;
491 ret = attrcount;
492 return ret;
493}
494
495static ssize_t iio_buffer_read_length(struct device *dev,
496 struct device_attribute *attr,
497 char *buf)
498{
499 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
500 struct iio_buffer *buffer = indio_dev->buffer;
501
502 return sprintf(buf, "%d\n", buffer->length);
503}
504
505static ssize_t iio_buffer_write_length(struct device *dev,
506 struct device_attribute *attr,
507 const char *buf, size_t len)
508{
509 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
510 struct iio_buffer *buffer = indio_dev->buffer;
511 unsigned int val;
512 int ret;
513
514 ret = kstrtouint(buf, 10, &val);
515 if (ret)
516 return ret;
517
518 if (val == buffer->length)
519 return len;
520
521 mutex_lock(&indio_dev->mlock);
522 if (iio_buffer_is_active(indio_dev->buffer)) {
523 ret = -EBUSY;
524 } else {
525 buffer->access->set_length(buffer, val);
526 ret = 0;
527 }
528 if (ret)
529 goto out;
530 if (buffer->length && buffer->length < buffer->watermark)
531 buffer->watermark = buffer->length;
532out:
533 mutex_unlock(&indio_dev->mlock);
534
535 return ret ? ret : len;
536}
537
538static ssize_t iio_buffer_show_enable(struct device *dev,
539 struct device_attribute *attr,
540 char *buf)
541{
542 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
543 return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer));
544}
545
546static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev,
547 unsigned int scan_index)
548{
549 const struct iio_chan_spec *ch;
550 unsigned int bytes;
551
552 ch = iio_find_channel_from_si(indio_dev, scan_index);
553 bytes = ch->scan_type.storagebits / 8;
554 if (ch->scan_type.repeat > 1)
555 bytes *= ch->scan_type.repeat;
556 return bytes;
557}
558
559static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev)
560{
561 return iio_storage_bytes_for_si(indio_dev,
562 indio_dev->scan_index_timestamp);
563}
564
565static int iio_compute_scan_bytes(struct iio_dev *indio_dev,
566 const unsigned long *mask, bool timestamp)
567{
568 unsigned bytes = 0;
569 int length, i;
570
571
572 for_each_set_bit(i, mask,
573 indio_dev->masklength) {
574 length = iio_storage_bytes_for_si(indio_dev, i);
575 bytes = ALIGN(bytes, length);
576 bytes += length;
577 }
578
579 if (timestamp) {
580 length = iio_storage_bytes_for_timestamp(indio_dev);
581 bytes = ALIGN(bytes, length);
582 bytes += length;
583 }
584 return bytes;
585}
586
587static void iio_buffer_activate(struct iio_dev *indio_dev,
588 struct iio_buffer *buffer)
589{
590 iio_buffer_get(buffer);
591 list_add(&buffer->buffer_list, &indio_dev->buffer_list);
592}
593
594static void iio_buffer_deactivate(struct iio_buffer *buffer)
595{
596 list_del_init(&buffer->buffer_list);
597 wake_up_interruptible(&buffer->pollq);
598 iio_buffer_put(buffer);
599}
600
601static void iio_buffer_deactivate_all(struct iio_dev *indio_dev)
602{
603 struct iio_buffer *buffer, *_buffer;
604
605 list_for_each_entry_safe(buffer, _buffer,
606 &indio_dev->buffer_list, buffer_list)
607 iio_buffer_deactivate(buffer);
608}
609
610static int iio_buffer_enable(struct iio_buffer *buffer,
611 struct iio_dev *indio_dev)
612{
613 if (!buffer->access->enable)
614 return 0;
615 return buffer->access->enable(buffer, indio_dev);
616}
617
618static int iio_buffer_disable(struct iio_buffer *buffer,
619 struct iio_dev *indio_dev)
620{
621 if (!buffer->access->disable)
622 return 0;
623 return buffer->access->disable(buffer, indio_dev);
624}
625
626static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev,
627 struct iio_buffer *buffer)
628{
629 unsigned int bytes;
630
631 if (!buffer->access->set_bytes_per_datum)
632 return;
633
634 bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask,
635 buffer->scan_timestamp);
636
637 buffer->access->set_bytes_per_datum(buffer, bytes);
638}
639
640static int iio_buffer_request_update(struct iio_dev *indio_dev,
641 struct iio_buffer *buffer)
642{
643 int ret;
644
645 iio_buffer_update_bytes_per_datum(indio_dev, buffer);
646 if (buffer->access->request_update) {
647 ret = buffer->access->request_update(buffer);
648 if (ret) {
649 dev_dbg(&indio_dev->dev,
650 "Buffer not started: buffer parameter update failed (%d)\n",
651 ret);
652 return ret;
653 }
654 }
655
656 return 0;
657}
658
659static void iio_free_scan_mask(struct iio_dev *indio_dev,
660 const unsigned long *mask)
661{
662
663 if (!indio_dev->available_scan_masks)
664 bitmap_free(mask);
665}
666
667struct iio_device_config {
668 unsigned int mode;
669 unsigned int watermark;
670 const unsigned long *scan_mask;
671 unsigned int scan_bytes;
672 bool scan_timestamp;
673};
674
675static int iio_verify_update(struct iio_dev *indio_dev,
676 struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer,
677 struct iio_device_config *config)
678{
679 unsigned long *compound_mask;
680 const unsigned long *scan_mask;
681 bool strict_scanmask = false;
682 struct iio_buffer *buffer;
683 bool scan_timestamp;
684 unsigned int modes;
685
686 memset(config, 0, sizeof(*config));
687 config->watermark = ~0;
688
689
690
691
692
693 if (remove_buffer && !insert_buffer &&
694 list_is_singular(&indio_dev->buffer_list))
695 return 0;
696
697 modes = indio_dev->modes;
698
699 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
700 if (buffer == remove_buffer)
701 continue;
702 modes &= buffer->access->modes;
703 config->watermark = min(config->watermark, buffer->watermark);
704 }
705
706 if (insert_buffer) {
707 modes &= insert_buffer->access->modes;
708 config->watermark = min(config->watermark,
709 insert_buffer->watermark);
710 }
711
712
713 if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) {
714 config->mode = INDIO_BUFFER_TRIGGERED;
715 } else if (modes & INDIO_BUFFER_HARDWARE) {
716
717
718
719
720 if (insert_buffer && !list_empty(&indio_dev->buffer_list))
721 return -EINVAL;
722 config->mode = INDIO_BUFFER_HARDWARE;
723 strict_scanmask = true;
724 } else if (modes & INDIO_BUFFER_SOFTWARE) {
725 config->mode = INDIO_BUFFER_SOFTWARE;
726 } else {
727
728 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
729 dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n");
730 return -EINVAL;
731 }
732
733
734 compound_mask = bitmap_zalloc(indio_dev->masklength, GFP_KERNEL);
735 if (compound_mask == NULL)
736 return -ENOMEM;
737
738 scan_timestamp = false;
739
740 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
741 if (buffer == remove_buffer)
742 continue;
743 bitmap_or(compound_mask, compound_mask, buffer->scan_mask,
744 indio_dev->masklength);
745 scan_timestamp |= buffer->scan_timestamp;
746 }
747
748 if (insert_buffer) {
749 bitmap_or(compound_mask, compound_mask,
750 insert_buffer->scan_mask, indio_dev->masklength);
751 scan_timestamp |= insert_buffer->scan_timestamp;
752 }
753
754 if (indio_dev->available_scan_masks) {
755 scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks,
756 indio_dev->masklength,
757 compound_mask,
758 strict_scanmask);
759 bitmap_free(compound_mask);
760 if (scan_mask == NULL)
761 return -EINVAL;
762 } else {
763 scan_mask = compound_mask;
764 }
765
766 config->scan_bytes = iio_compute_scan_bytes(indio_dev,
767 scan_mask, scan_timestamp);
768 config->scan_mask = scan_mask;
769 config->scan_timestamp = scan_timestamp;
770
771 return 0;
772}
773
774
775
776
777
778
779
780
781struct iio_demux_table {
782 unsigned from;
783 unsigned to;
784 unsigned length;
785 struct list_head l;
786};
787
788static void iio_buffer_demux_free(struct iio_buffer *buffer)
789{
790 struct iio_demux_table *p, *q;
791 list_for_each_entry_safe(p, q, &buffer->demux_list, l) {
792 list_del(&p->l);
793 kfree(p);
794 }
795}
796
797static int iio_buffer_add_demux(struct iio_buffer *buffer,
798 struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc,
799 unsigned int length)
800{
801
802 if (*p && (*p)->from + (*p)->length == in_loc &&
803 (*p)->to + (*p)->length == out_loc) {
804 (*p)->length += length;
805 } else {
806 *p = kmalloc(sizeof(**p), GFP_KERNEL);
807 if (*p == NULL)
808 return -ENOMEM;
809 (*p)->from = in_loc;
810 (*p)->to = out_loc;
811 (*p)->length = length;
812 list_add_tail(&(*p)->l, &buffer->demux_list);
813 }
814
815 return 0;
816}
817
818static int iio_buffer_update_demux(struct iio_dev *indio_dev,
819 struct iio_buffer *buffer)
820{
821 int ret, in_ind = -1, out_ind, length;
822 unsigned in_loc = 0, out_loc = 0;
823 struct iio_demux_table *p = NULL;
824
825
826 iio_buffer_demux_free(buffer);
827 kfree(buffer->demux_bounce);
828 buffer->demux_bounce = NULL;
829
830
831 if (bitmap_equal(indio_dev->active_scan_mask,
832 buffer->scan_mask,
833 indio_dev->masklength))
834 return 0;
835
836
837 for_each_set_bit(out_ind,
838 buffer->scan_mask,
839 indio_dev->masklength) {
840 in_ind = find_next_bit(indio_dev->active_scan_mask,
841 indio_dev->masklength,
842 in_ind + 1);
843 while (in_ind != out_ind) {
844 in_ind = find_next_bit(indio_dev->active_scan_mask,
845 indio_dev->masklength,
846 in_ind + 1);
847 length = iio_storage_bytes_for_si(indio_dev, in_ind);
848
849 in_loc = roundup(in_loc, length) + length;
850 }
851 length = iio_storage_bytes_for_si(indio_dev, in_ind);
852 out_loc = roundup(out_loc, length);
853 in_loc = roundup(in_loc, length);
854 ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length);
855 if (ret)
856 goto error_clear_mux_table;
857 out_loc += length;
858 in_loc += length;
859 }
860
861 if (buffer->scan_timestamp) {
862 length = iio_storage_bytes_for_timestamp(indio_dev);
863 out_loc = roundup(out_loc, length);
864 in_loc = roundup(in_loc, length);
865 ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length);
866 if (ret)
867 goto error_clear_mux_table;
868 out_loc += length;
869 in_loc += length;
870 }
871 buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL);
872 if (buffer->demux_bounce == NULL) {
873 ret = -ENOMEM;
874 goto error_clear_mux_table;
875 }
876 return 0;
877
878error_clear_mux_table:
879 iio_buffer_demux_free(buffer);
880
881 return ret;
882}
883
884static int iio_update_demux(struct iio_dev *indio_dev)
885{
886 struct iio_buffer *buffer;
887 int ret;
888
889 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
890 ret = iio_buffer_update_demux(indio_dev, buffer);
891 if (ret < 0)
892 goto error_clear_mux_table;
893 }
894 return 0;
895
896error_clear_mux_table:
897 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list)
898 iio_buffer_demux_free(buffer);
899
900 return ret;
901}
902
903static int iio_enable_buffers(struct iio_dev *indio_dev,
904 struct iio_device_config *config)
905{
906 struct iio_buffer *buffer;
907 int ret;
908
909 indio_dev->active_scan_mask = config->scan_mask;
910 indio_dev->scan_timestamp = config->scan_timestamp;
911 indio_dev->scan_bytes = config->scan_bytes;
912
913 iio_update_demux(indio_dev);
914
915
916 if (indio_dev->setup_ops->preenable) {
917 ret = indio_dev->setup_ops->preenable(indio_dev);
918 if (ret) {
919 dev_dbg(&indio_dev->dev,
920 "Buffer not started: buffer preenable failed (%d)\n", ret);
921 goto err_undo_config;
922 }
923 }
924
925 if (indio_dev->info->update_scan_mode) {
926 ret = indio_dev->info
927 ->update_scan_mode(indio_dev,
928 indio_dev->active_scan_mask);
929 if (ret < 0) {
930 dev_dbg(&indio_dev->dev,
931 "Buffer not started: update scan mode failed (%d)\n",
932 ret);
933 goto err_run_postdisable;
934 }
935 }
936
937 if (indio_dev->info->hwfifo_set_watermark)
938 indio_dev->info->hwfifo_set_watermark(indio_dev,
939 config->watermark);
940
941 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
942 ret = iio_buffer_enable(buffer, indio_dev);
943 if (ret)
944 goto err_disable_buffers;
945 }
946
947 indio_dev->currentmode = config->mode;
948
949 if (indio_dev->setup_ops->postenable) {
950 ret = indio_dev->setup_ops->postenable(indio_dev);
951 if (ret) {
952 dev_dbg(&indio_dev->dev,
953 "Buffer not started: postenable failed (%d)\n", ret);
954 goto err_disable_buffers;
955 }
956 }
957
958 return 0;
959
960err_disable_buffers:
961 list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list,
962 buffer_list)
963 iio_buffer_disable(buffer, indio_dev);
964err_run_postdisable:
965 indio_dev->currentmode = INDIO_DIRECT_MODE;
966 if (indio_dev->setup_ops->postdisable)
967 indio_dev->setup_ops->postdisable(indio_dev);
968err_undo_config:
969 indio_dev->active_scan_mask = NULL;
970
971 return ret;
972}
973
974static int iio_disable_buffers(struct iio_dev *indio_dev)
975{
976 struct iio_buffer *buffer;
977 int ret = 0;
978 int ret2;
979
980
981 if (list_empty(&indio_dev->buffer_list))
982 return 0;
983
984
985
986
987
988
989
990
991 if (indio_dev->setup_ops->predisable) {
992 ret2 = indio_dev->setup_ops->predisable(indio_dev);
993 if (ret2 && !ret)
994 ret = ret2;
995 }
996
997 list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
998 ret2 = iio_buffer_disable(buffer, indio_dev);
999 if (ret2 && !ret)
1000 ret = ret2;
1001 }
1002
1003 indio_dev->currentmode = INDIO_DIRECT_MODE;
1004
1005 if (indio_dev->setup_ops->postdisable) {
1006 ret2 = indio_dev->setup_ops->postdisable(indio_dev);
1007 if (ret2 && !ret)
1008 ret = ret2;
1009 }
1010
1011 iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask);
1012 indio_dev->active_scan_mask = NULL;
1013
1014 return ret;
1015}
1016
1017static int __iio_update_buffers(struct iio_dev *indio_dev,
1018 struct iio_buffer *insert_buffer,
1019 struct iio_buffer *remove_buffer)
1020{
1021 struct iio_device_config new_config;
1022 int ret;
1023
1024 ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer,
1025 &new_config);
1026 if (ret)
1027 return ret;
1028
1029 if (insert_buffer) {
1030 ret = iio_buffer_request_update(indio_dev, insert_buffer);
1031 if (ret)
1032 goto err_free_config;
1033 }
1034
1035 ret = iio_disable_buffers(indio_dev);
1036 if (ret)
1037 goto err_deactivate_all;
1038
1039 if (remove_buffer)
1040 iio_buffer_deactivate(remove_buffer);
1041 if (insert_buffer)
1042 iio_buffer_activate(indio_dev, insert_buffer);
1043
1044
1045 if (list_empty(&indio_dev->buffer_list))
1046 return 0;
1047
1048 ret = iio_enable_buffers(indio_dev, &new_config);
1049 if (ret)
1050 goto err_deactivate_all;
1051
1052 return 0;
1053
1054err_deactivate_all:
1055
1056
1057
1058
1059
1060
1061
1062
1063 iio_buffer_deactivate_all(indio_dev);
1064
1065err_free_config:
1066 iio_free_scan_mask(indio_dev, new_config.scan_mask);
1067 return ret;
1068}
1069
1070int iio_update_buffers(struct iio_dev *indio_dev,
1071 struct iio_buffer *insert_buffer,
1072 struct iio_buffer *remove_buffer)
1073{
1074 int ret;
1075
1076 if (insert_buffer == remove_buffer)
1077 return 0;
1078
1079 mutex_lock(&indio_dev->info_exist_lock);
1080 mutex_lock(&indio_dev->mlock);
1081
1082 if (insert_buffer && iio_buffer_is_active(insert_buffer))
1083 insert_buffer = NULL;
1084
1085 if (remove_buffer && !iio_buffer_is_active(remove_buffer))
1086 remove_buffer = NULL;
1087
1088 if (!insert_buffer && !remove_buffer) {
1089 ret = 0;
1090 goto out_unlock;
1091 }
1092
1093 if (indio_dev->info == NULL) {
1094 ret = -ENODEV;
1095 goto out_unlock;
1096 }
1097
1098 ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer);
1099
1100out_unlock:
1101 mutex_unlock(&indio_dev->mlock);
1102 mutex_unlock(&indio_dev->info_exist_lock);
1103
1104 return ret;
1105}
1106EXPORT_SYMBOL_GPL(iio_update_buffers);
1107
1108void iio_disable_all_buffers(struct iio_dev *indio_dev)
1109{
1110 iio_disable_buffers(indio_dev);
1111 iio_buffer_deactivate_all(indio_dev);
1112}
1113
1114static ssize_t iio_buffer_store_enable(struct device *dev,
1115 struct device_attribute *attr,
1116 const char *buf,
1117 size_t len)
1118{
1119 int ret;
1120 bool requested_state;
1121 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1122 bool inlist;
1123
1124 ret = strtobool(buf, &requested_state);
1125 if (ret < 0)
1126 return ret;
1127
1128 mutex_lock(&indio_dev->mlock);
1129
1130
1131 inlist = iio_buffer_is_active(indio_dev->buffer);
1132
1133 if (inlist == requested_state)
1134 goto done;
1135
1136 if (requested_state)
1137 ret = __iio_update_buffers(indio_dev,
1138 indio_dev->buffer, NULL);
1139 else
1140 ret = __iio_update_buffers(indio_dev,
1141 NULL, indio_dev->buffer);
1142
1143done:
1144 mutex_unlock(&indio_dev->mlock);
1145 return (ret < 0) ? ret : len;
1146}
1147
1148static const char * const iio_scan_elements_group_name = "scan_elements";
1149
1150static ssize_t iio_buffer_show_watermark(struct device *dev,
1151 struct device_attribute *attr,
1152 char *buf)
1153{
1154 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1155 struct iio_buffer *buffer = indio_dev->buffer;
1156
1157 return sprintf(buf, "%u\n", buffer->watermark);
1158}
1159
1160static ssize_t iio_buffer_store_watermark(struct device *dev,
1161 struct device_attribute *attr,
1162 const char *buf,
1163 size_t len)
1164{
1165 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1166 struct iio_buffer *buffer = indio_dev->buffer;
1167 unsigned int val;
1168 int ret;
1169
1170 ret = kstrtouint(buf, 10, &val);
1171 if (ret)
1172 return ret;
1173 if (!val)
1174 return -EINVAL;
1175
1176 mutex_lock(&indio_dev->mlock);
1177
1178 if (val > buffer->length) {
1179 ret = -EINVAL;
1180 goto out;
1181 }
1182
1183 if (iio_buffer_is_active(indio_dev->buffer)) {
1184 ret = -EBUSY;
1185 goto out;
1186 }
1187
1188 buffer->watermark = val;
1189out:
1190 mutex_unlock(&indio_dev->mlock);
1191
1192 return ret ? ret : len;
1193}
1194
1195static ssize_t iio_dma_show_data_available(struct device *dev,
1196 struct device_attribute *attr,
1197 char *buf)
1198{
1199 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1200 size_t bytes;
1201
1202 bytes = iio_buffer_data_available(indio_dev->buffer);
1203
1204 return sprintf(buf, "%zu\n", bytes);
1205}
1206
1207static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length,
1208 iio_buffer_write_length);
1209static struct device_attribute dev_attr_length_ro = __ATTR(length,
1210 S_IRUGO, iio_buffer_read_length, NULL);
1211static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR,
1212 iio_buffer_show_enable, iio_buffer_store_enable);
1213static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR,
1214 iio_buffer_show_watermark, iio_buffer_store_watermark);
1215static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark,
1216 S_IRUGO, iio_buffer_show_watermark, NULL);
1217static DEVICE_ATTR(data_available, S_IRUGO,
1218 iio_dma_show_data_available, NULL);
1219
1220static struct attribute *iio_buffer_attrs[] = {
1221 &dev_attr_length.attr,
1222 &dev_attr_enable.attr,
1223 &dev_attr_watermark.attr,
1224 &dev_attr_data_available.attr,
1225};
1226
1227int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
1228{
1229 struct iio_dev_attr *p;
1230 struct attribute **attr;
1231 struct iio_buffer *buffer = indio_dev->buffer;
1232 int ret, i, attrn, attrcount, attrcount_orig = 0;
1233 const struct iio_chan_spec *channels;
1234
1235 channels = indio_dev->channels;
1236 if (channels) {
1237 int ml = indio_dev->masklength;
1238
1239 for (i = 0; i < indio_dev->num_channels; i++)
1240 ml = max(ml, channels[i].scan_index + 1);
1241 indio_dev->masklength = ml;
1242 }
1243
1244 if (!buffer)
1245 return 0;
1246
1247 attrcount = 0;
1248 if (buffer->attrs) {
1249 while (buffer->attrs[attrcount] != NULL)
1250 attrcount++;
1251 }
1252
1253 attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1,
1254 sizeof(struct attribute *), GFP_KERNEL);
1255 if (!attr)
1256 return -ENOMEM;
1257
1258 memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs));
1259 if (!buffer->access->set_length)
1260 attr[0] = &dev_attr_length_ro.attr;
1261
1262 if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK)
1263 attr[2] = &dev_attr_watermark_ro.attr;
1264
1265 if (buffer->attrs)
1266 memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs,
1267 sizeof(struct attribute *) * attrcount);
1268
1269 attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL;
1270
1271 buffer->buffer_group.name = "buffer";
1272 buffer->buffer_group.attrs = attr;
1273
1274 indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group;
1275
1276 if (buffer->scan_el_attrs != NULL) {
1277 attr = buffer->scan_el_attrs->attrs;
1278 while (*attr++ != NULL)
1279 attrcount_orig++;
1280 }
1281 attrcount = attrcount_orig;
1282 INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list);
1283 channels = indio_dev->channels;
1284 if (channels) {
1285
1286 for (i = 0; i < indio_dev->num_channels; i++) {
1287 if (channels[i].scan_index < 0)
1288 continue;
1289
1290 ret = iio_buffer_add_channel_sysfs(indio_dev,
1291 &channels[i]);
1292 if (ret < 0)
1293 goto error_cleanup_dynamic;
1294 attrcount += ret;
1295 if (channels[i].type == IIO_TIMESTAMP)
1296 indio_dev->scan_index_timestamp =
1297 channels[i].scan_index;
1298 }
1299 if (indio_dev->masklength && buffer->scan_mask == NULL) {
1300 buffer->scan_mask = bitmap_zalloc(indio_dev->masklength,
1301 GFP_KERNEL);
1302 if (buffer->scan_mask == NULL) {
1303 ret = -ENOMEM;
1304 goto error_cleanup_dynamic;
1305 }
1306 }
1307 }
1308
1309 buffer->scan_el_group.name = iio_scan_elements_group_name;
1310
1311 buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
1312 sizeof(buffer->scan_el_group.attrs[0]),
1313 GFP_KERNEL);
1314 if (buffer->scan_el_group.attrs == NULL) {
1315 ret = -ENOMEM;
1316 goto error_free_scan_mask;
1317 }
1318 if (buffer->scan_el_attrs)
1319 memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs,
1320 sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig);
1321 attrn = attrcount_orig;
1322
1323 list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l)
1324 buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
1325 indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group;
1326
1327 return 0;
1328
1329error_free_scan_mask:
1330 bitmap_free(buffer->scan_mask);
1331error_cleanup_dynamic:
1332 iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
1333 kfree(indio_dev->buffer->buffer_group.attrs);
1334
1335 return ret;
1336}
1337
1338void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
1339{
1340 if (!indio_dev->buffer)
1341 return;
1342
1343 bitmap_free(indio_dev->buffer->scan_mask);
1344 kfree(indio_dev->buffer->buffer_group.attrs);
1345 kfree(indio_dev->buffer->scan_el_group.attrs);
1346 iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list);
1347}
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
1359 const unsigned long *mask)
1360{
1361 return bitmap_weight(mask, indio_dev->masklength) == 1;
1362}
1363EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot);
1364
1365static const void *iio_demux(struct iio_buffer *buffer,
1366 const void *datain)
1367{
1368 struct iio_demux_table *t;
1369
1370 if (list_empty(&buffer->demux_list))
1371 return datain;
1372 list_for_each_entry(t, &buffer->demux_list, l)
1373 memcpy(buffer->demux_bounce + t->to,
1374 datain + t->from, t->length);
1375
1376 return buffer->demux_bounce;
1377}
1378
1379static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data)
1380{
1381 const void *dataout = iio_demux(buffer, data);
1382 int ret;
1383
1384 ret = buffer->access->store_to(buffer, dataout);
1385 if (ret)
1386 return ret;
1387
1388
1389
1390
1391
1392 wake_up_interruptible_poll(&buffer->pollq, EPOLLIN | EPOLLRDNORM);
1393 return 0;
1394}
1395
1396
1397
1398
1399
1400
1401int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data)
1402{
1403 int ret;
1404 struct iio_buffer *buf;
1405
1406 list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) {
1407 ret = iio_push_to_buffer(buf, data);
1408 if (ret < 0)
1409 return ret;
1410 }
1411
1412 return 0;
1413}
1414EXPORT_SYMBOL_GPL(iio_push_to_buffers);
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425static void iio_buffer_release(struct kref *ref)
1426{
1427 struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref);
1428
1429 buffer->access->release(buffer);
1430}
1431
1432
1433
1434
1435
1436
1437
1438struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer)
1439{
1440 if (buffer)
1441 kref_get(&buffer->ref);
1442
1443 return buffer;
1444}
1445EXPORT_SYMBOL_GPL(iio_buffer_get);
1446
1447
1448
1449
1450
1451void iio_buffer_put(struct iio_buffer *buffer)
1452{
1453 if (buffer)
1454 kref_put(&buffer->ref, iio_buffer_release);
1455}
1456EXPORT_SYMBOL_GPL(iio_buffer_put);
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467void iio_device_attach_buffer(struct iio_dev *indio_dev,
1468 struct iio_buffer *buffer)
1469{
1470 indio_dev->buffer = iio_buffer_get(buffer);
1471}
1472EXPORT_SYMBOL_GPL(iio_device_attach_buffer);
1473