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1// SPDX-License-Identifier: GPL-2.0-only
2/* Industrialio buffer test code.
3 *
4 * Copyright (c) 2008 Jonathan Cameron
5 *
6 * This program is primarily intended as an example application.
7 * Reads the current buffer setup from sysfs and starts a short capture
8 * from the specified device, pretty printing the result after appropriate
9 * conversion.
10 *
11 * Command line parameters
12 * generic_buffer -n <device_name> -t <trigger_name>
13 * If trigger name is not specified the program assumes you want a dataready
14 * trigger associated with the device and goes looking for it.
15 */
16
17#include <unistd.h>
18#include <stdlib.h>
19#include <dirent.h>
20#include <fcntl.h>
21#include <stdio.h>
22#include <errno.h>
23#include <sys/stat.h>
24#include <sys/dir.h>
25#include <linux/types.h>
26#include <string.h>
27#include <poll.h>
28#include <endian.h>
29#include <float.h>
30#include <getopt.h>
31#include <inttypes.h>
32#include <stdbool.h>
33#include <signal.h>
34#include <sys/ioctl.h>
35#include <linux/iio/buffer.h>
36#include "iio_utils.h"
37
38/**
39 * enum autochan - state for the automatic channel enabling mechanism
40 */
41enum autochan {
42 AUTOCHANNELS_DISABLED,
43 AUTOCHANNELS_ENABLED,
44 AUTOCHANNELS_ACTIVE,
45};
46
47/**
48 * size_from_channelarray() - calculate the storage size of a scan
49 * @channels: the channel info array
50 * @num_channels: number of channels
51 *
52 * Has the side effect of filling the channels[i].location values used
53 * in processing the buffer output.
54 **/
55static unsigned int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
56{
57 unsigned int bytes = 0;
58 int i = 0, max = 0;
59 unsigned int misalignment;
60
61 while (i < num_channels) {
62 if (channels[i].bytes > max)
63 max = channels[i].bytes;
64 if (bytes % channels[i].bytes == 0)
65 channels[i].location = bytes;
66 else
67 channels[i].location = bytes - bytes % channels[i].bytes
68 + channels[i].bytes;
69
70 bytes = channels[i].location + channels[i].bytes;
71 i++;
72 }
73 /*
74 * We want the data in next sample to also be properly aligned so
75 * we'll add padding at the end if needed. Adding padding only
76 * works for channel data which size is 2^n bytes.
77 */
78 misalignment = bytes % max;
79 if (misalignment)
80 bytes += max - misalignment;
81
82 return bytes;
83}
84
85static void print1byte(uint8_t input, struct iio_channel_info *info)
86{
87 /*
88 * Shift before conversion to avoid sign extension
89 * of left aligned data
90 */
91 input >>= info->shift;
92 input &= info->mask;
93 switch (info->format) {
94 case 's': {
95 int8_t val = (int8_t)(input << (8 - info->bits_used)) >>
96 (8 - info->bits_used);
97 printf("%05f ", ((float)val + info->offset) * info->scale);
98 break;
99 }
100 case 'u':
101 printf("%05f ", ((float)input + info->offset) * info->scale);
102 break;
103 case 'f':
104 printf("<invalid 1-byte float> ");
105 break;
106 }
107}
108
109static void print2byte(uint16_t input, struct iio_channel_info *info)
110{
111 /* First swap if incorrect endian */
112 if (info->be)
113 input = be16toh(input);
114 else
115 input = le16toh(input);
116
117 /*
118 * Shift before conversion to avoid sign extension
119 * of left aligned data
120 */
121 input >>= info->shift;
122 input &= info->mask;
123 switch (info->format) {
124 case 's': {
125 int16_t val = (int16_t)(input << (16 - info->bits_used)) >>
126 (16 - info->bits_used);
127 printf("%05f ", ((float)val + info->offset) * info->scale);
128 break;
129 }
130 case 'u':
131 printf("%05f ", ((float)input + info->offset) * info->scale);
132 break;
133 case 'f': {
134#if defined(__FLT16_MAX__)
135 union {
136 uint16_t u;
137 _Float16 f;
138 } converter;
139
140 converter.u = input;
141 printf("%05f ", ((float)converter.f + info->offset) * info->scale);
142#else
143 printf("<unsupported 2-byte float> ");
144#endif
145 break;
146 }
147 }
148}
149
150static void print4byte(uint32_t input, struct iio_channel_info *info)
151{
152 /* First swap if incorrect endian */
153 if (info->be)
154 input = be32toh(input);
155 else
156 input = le32toh(input);
157
158 /*
159 * Shift before conversion to avoid sign extension
160 * of left aligned data
161 */
162 input >>= info->shift;
163 input &= info->mask;
164 switch (info->format) {
165 case 's': {
166 int32_t val = (int32_t)(input << (32 - info->bits_used)) >>
167 (32 - info->bits_used);
168 printf("%05f ", ((float)val + info->offset) * info->scale);
169 break;
170 }
171 case 'u':
172 printf("%05f ", ((float)input + info->offset) * info->scale);
173 break;
174 case 'f': {
175 union {
176 uint32_t u;
177 float f;
178 } converter;
179
180 converter.u = input;
181 printf("%05f ", (converter.f + info->offset) * info->scale);
182 break;
183 }
184 }
185}
186
187static void print8byte(uint64_t input, struct iio_channel_info *info)
188{
189 /* First swap if incorrect endian */
190 if (info->be)
191 input = be64toh(input);
192 else
193 input = le64toh(input);
194
195 /*
196 * Shift before conversion to avoid sign extension
197 * of left aligned data
198 */
199 input >>= info->shift;
200 input &= info->mask;
201 switch (info->format) {
202 case 's': {
203 int64_t val = (int64_t)(input << (64 - info->bits_used)) >>
204 (64 - info->bits_used);
205 /* special case for timestamp */
206 if (info->scale == 1.0f && info->offset == 0.0f)
207 printf("%" PRId64 " ", val);
208 else
209 printf("%05f ",
210 ((float)val + info->offset) * info->scale);
211 break;
212 }
213 case 'u':
214 printf("%05f ", ((float)input + info->offset) * info->scale);
215 break;
216 case 'f': {
217 union {
218 uint64_t u;
219 double f;
220 } converter;
221
222 converter.u = input;
223 printf("%05f ", (converter.f + info->offset) * info->scale);
224 break;
225 }
226 }
227}
228
229/**
230 * process_scan() - print out the values in SI units
231 * @data: pointer to the start of the scan
232 * @channels: information about the channels.
233 * Note: size_from_channelarray must have been called first
234 * to fill the location offsets.
235 * @num_channels: number of channels
236 **/
237static void process_scan(char *data, struct iio_channel_info *channels,
238 int num_channels)
239{
240 int k;
241
242 for (k = 0; k < num_channels; k++)
243 switch (channels[k].bytes) {
244 /* only a few cases implemented so far */
245 case 1:
246 print1byte(*(uint8_t *)(data + channels[k].location),
247 &channels[k]);
248 break;
249 case 2:
250 print2byte(*(uint16_t *)(data + channels[k].location),
251 &channels[k]);
252 break;
253 case 4:
254 print4byte(*(uint32_t *)(data + channels[k].location),
255 &channels[k]);
256 break;
257 case 8:
258 print8byte(*(uint64_t *)(data + channels[k].location),
259 &channels[k]);
260 break;
261 default:
262 break;
263 }
264 printf("\n");
265}
266
267static int enable_disable_all_channels(char *dev_dir_name, int buffer_idx, int enable)
268{
269 const struct dirent *ent;
270 char scanelemdir[256];
271 DIR *dp;
272 int ret;
273
274 snprintf(scanelemdir, sizeof(scanelemdir),
275 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name, buffer_idx);
276 scanelemdir[sizeof(scanelemdir)-1] = '\0';
277
278 dp = opendir(scanelemdir);
279 if (!dp) {
280 fprintf(stderr, "Enabling/disabling channels: can't open %s\n",
281 scanelemdir);
282 return -EIO;
283 }
284
285 ret = -ENOENT;
286 while (ent = readdir(dp), ent) {
287 if (iioutils_check_suffix(ent->d_name, "_en")) {
288 printf("%sabling: %s\n",
289 enable ? "En" : "Dis",
290 ent->d_name);
291 ret = write_sysfs_int(ent->d_name, scanelemdir,
292 enable);
293 if (ret < 0)
294 fprintf(stderr, "Failed to enable/disable %s\n",
295 ent->d_name);
296 }
297 }
298
299 if (closedir(dp) == -1) {
300 perror("Enabling/disabling channels: "
301 "Failed to close directory");
302 return -errno;
303 }
304 return 0;
305}
306
307static void print_usage(void)
308{
309 fprintf(stderr, "Usage: generic_buffer [options]...\n"
310 "Capture, convert and output data from IIO device buffer\n"
311 " -a Auto-activate all available channels\n"
312 " -A Force-activate ALL channels\n"
313 " -b <n> The buffer which to open (by index), default 0\n"
314 " -c <n> Do n conversions, or loop forever if n < 0\n"
315 " -e Disable wait for event (new data)\n"
316 " -g Use trigger-less mode\n"
317 " -l <n> Set buffer length to n samples\n"
318 " --device-name -n <name>\n"
319 " --device-num -N <num>\n"
320 " Set device by name or number (mandatory)\n"
321 " --trigger-name -t <name>\n"
322 " --trigger-num -T <num>\n"
323 " Set trigger by name or number\n"
324 " -w <n> Set delay between reads in us (event-less mode)\n");
325}
326
327static enum autochan autochannels = AUTOCHANNELS_DISABLED;
328static char *dev_dir_name = NULL;
329static char *buf_dir_name = NULL;
330static int buffer_idx = 0;
331static bool current_trigger_set = false;
332
333static void cleanup(void)
334{
335 int ret;
336
337 /* Disable trigger */
338 if (dev_dir_name && current_trigger_set) {
339 /* Disconnect the trigger - just write a dummy name. */
340 ret = write_sysfs_string("trigger/current_trigger",
341 dev_dir_name, "NULL");
342 if (ret < 0)
343 fprintf(stderr, "Failed to disable trigger: %s\n",
344 strerror(-ret));
345 current_trigger_set = false;
346 }
347
348 /* Disable buffer */
349 if (buf_dir_name) {
350 ret = write_sysfs_int("enable", buf_dir_name, 0);
351 if (ret < 0)
352 fprintf(stderr, "Failed to disable buffer: %s\n",
353 strerror(-ret));
354 }
355
356 /* Disable channels if auto-enabled */
357 if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {
358 ret = enable_disable_all_channels(dev_dir_name, buffer_idx, 0);
359 if (ret)
360 fprintf(stderr, "Failed to disable all channels\n");
361 autochannels = AUTOCHANNELS_DISABLED;
362 }
363}
364
365static void sig_handler(int signum)
366{
367 fprintf(stderr, "Caught signal %d\n", signum);
368 cleanup();
369 exit(-signum);
370}
371
372static void register_cleanup(void)
373{
374 struct sigaction sa = { .sa_handler = sig_handler };
375 const int signums[] = { SIGINT, SIGTERM, SIGABRT };
376 int ret, i;
377
378 for (i = 0; i < ARRAY_SIZE(signums); ++i) {
379 ret = sigaction(signums[i], &sa, NULL);
380 if (ret) {
381 perror("Failed to register signal handler");
382 exit(-1);
383 }
384 }
385}
386
387static const struct option longopts[] = {
388 { "device-name", 1, 0, 'n' },
389 { "device-num", 1, 0, 'N' },
390 { "trigger-name", 1, 0, 't' },
391 { "trigger-num", 1, 0, 'T' },
392 { }
393};
394
395int main(int argc, char **argv)
396{
397 long long num_loops = 2;
398 unsigned long timedelay = 1000000;
399 unsigned long buf_len = 128;
400
401 ssize_t i;
402 unsigned long long j;
403 unsigned long toread;
404 int ret, c;
405 struct stat st;
406 int fd = -1;
407 int buf_fd = -1;
408
409 int num_channels = 0;
410 char *trigger_name = NULL, *device_name = NULL;
411
412 char *data = NULL;
413 ssize_t read_size;
414 int dev_num = -1, trig_num = -1;
415 char *buffer_access = NULL;
416 unsigned int scan_size;
417 int noevents = 0;
418 int notrigger = 0;
419 char *dummy;
420 bool force_autochannels = false;
421
422 struct iio_channel_info *channels = NULL;
423
424 register_cleanup();
425
426 while ((c = getopt_long(argc, argv, "aAb:c:egl:n:N:t:T:w:?", longopts,
427 NULL)) != -1) {
428 switch (c) {
429 case 'a':
430 autochannels = AUTOCHANNELS_ENABLED;
431 break;
432 case 'A':
433 autochannels = AUTOCHANNELS_ENABLED;
434 force_autochannels = true;
435 break;
436 case 'b':
437 errno = 0;
438 buffer_idx = strtoll(optarg, &dummy, 10);
439 if (errno) {
440 ret = -errno;
441 goto error;
442 }
443 if (buffer_idx < 0) {
444 ret = -ERANGE;
445 goto error;
446 }
447
448 break;
449 case 'c':
450 errno = 0;
451 num_loops = strtoll(optarg, &dummy, 10);
452 if (errno) {
453 ret = -errno;
454 goto error;
455 }
456
457 break;
458 case 'e':
459 noevents = 1;
460 break;
461 case 'g':
462 notrigger = 1;
463 break;
464 case 'l':
465 errno = 0;
466 buf_len = strtoul(optarg, &dummy, 10);
467 if (errno) {
468 ret = -errno;
469 goto error;
470 }
471
472 break;
473 case 'n':
474 device_name = strdup(optarg);
475 break;
476 case 'N':
477 errno = 0;
478 dev_num = strtoul(optarg, &dummy, 10);
479 if (errno) {
480 ret = -errno;
481 goto error;
482 }
483 break;
484 case 't':
485 trigger_name = strdup(optarg);
486 break;
487 case 'T':
488 errno = 0;
489 trig_num = strtoul(optarg, &dummy, 10);
490 if (errno)
491 return -errno;
492 break;
493 case 'w':
494 errno = 0;
495 timedelay = strtoul(optarg, &dummy, 10);
496 if (errno) {
497 ret = -errno;
498 goto error;
499 }
500 break;
501 case '?':
502 print_usage();
503 ret = -1;
504 goto error;
505 }
506 }
507
508 /* Find the device requested */
509 if (dev_num < 0 && !device_name) {
510 fprintf(stderr, "Device not set\n");
511 print_usage();
512 ret = -1;
513 goto error;
514 } else if (dev_num >= 0 && device_name) {
515 fprintf(stderr, "Only one of --device-num or --device-name needs to be set\n");
516 print_usage();
517 ret = -1;
518 goto error;
519 } else if (dev_num < 0) {
520 dev_num = find_type_by_name(device_name, "iio:device");
521 if (dev_num < 0) {
522 fprintf(stderr, "Failed to find the %s\n", device_name);
523 ret = dev_num;
524 goto error;
525 }
526 }
527 printf("iio device number being used is %d\n", dev_num);
528
529 ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
530 if (ret < 0)
531 return -ENOMEM;
532 /* Fetch device_name if specified by number */
533 if (!device_name) {
534 device_name = malloc(IIO_MAX_NAME_LENGTH);
535 if (!device_name) {
536 ret = -ENOMEM;
537 goto error;
538 }
539 ret = read_sysfs_string("name", dev_dir_name, device_name);
540 if (ret < 0) {
541 fprintf(stderr, "Failed to read name of device %d\n", dev_num);
542 goto error;
543 }
544 }
545
546 if (notrigger) {
547 printf("trigger-less mode selected\n");
548 } else if (trig_num >= 0) {
549 char *trig_dev_name;
550 ret = asprintf(&trig_dev_name, "%strigger%d", iio_dir, trig_num);
551 if (ret < 0) {
552 return -ENOMEM;
553 }
554 trigger_name = malloc(IIO_MAX_NAME_LENGTH);
555 if (!trigger_name) {
556 ret = -ENOMEM;
557 goto error;
558 }
559 ret = read_sysfs_string("name", trig_dev_name, trigger_name);
560 free(trig_dev_name);
561 if (ret < 0) {
562 fprintf(stderr, "Failed to read trigger%d name from\n", trig_num);
563 return ret;
564 }
565 printf("iio trigger number being used is %d\n", trig_num);
566 } else {
567 if (!trigger_name) {
568 /*
569 * Build the trigger name. If it is device associated
570 * its name is <device_name>_dev[n] where n matches
571 * the device number found above.
572 */
573 ret = asprintf(&trigger_name,
574 "%s-dev%d", device_name, dev_num);
575 if (ret < 0) {
576 ret = -ENOMEM;
577 goto error;
578 }
579 }
580
581 /* Look for this "-devN" trigger */
582 trig_num = find_type_by_name(trigger_name, "trigger");
583 if (trig_num < 0) {
584 /* OK try the simpler "-trigger" suffix instead */
585 free(trigger_name);
586 ret = asprintf(&trigger_name,
587 "%s-trigger", device_name);
588 if (ret < 0) {
589 ret = -ENOMEM;
590 goto error;
591 }
592 }
593
594 trig_num = find_type_by_name(trigger_name, "trigger");
595 if (trig_num < 0) {
596 fprintf(stderr, "Failed to find the trigger %s\n",
597 trigger_name);
598 ret = trig_num;
599 goto error;
600 }
601
602 printf("iio trigger number being used is %d\n", trig_num);
603 }
604
605 /*
606 * Parse the files in scan_elements to identify what channels are
607 * present
608 */
609 ret = build_channel_array(dev_dir_name, buffer_idx, &channels, &num_channels);
610 if (ret) {
611 fprintf(stderr, "Problem reading scan element information\n"
612 "diag %s\n", dev_dir_name);
613 goto error;
614 }
615 if (num_channels && autochannels == AUTOCHANNELS_ENABLED &&
616 !force_autochannels) {
617 fprintf(stderr, "Auto-channels selected but some channels "
618 "are already activated in sysfs\n");
619 fprintf(stderr, "Proceeding without activating any channels\n");
620 }
621
622 if ((!num_channels && autochannels == AUTOCHANNELS_ENABLED) ||
623 (autochannels == AUTOCHANNELS_ENABLED && force_autochannels)) {
624 fprintf(stderr, "Enabling all channels\n");
625
626 ret = enable_disable_all_channels(dev_dir_name, buffer_idx, 1);
627 if (ret) {
628 fprintf(stderr, "Failed to enable all channels\n");
629 goto error;
630 }
631
632 /* This flags that we need to disable the channels again */
633 autochannels = AUTOCHANNELS_ACTIVE;
634
635 ret = build_channel_array(dev_dir_name, buffer_idx, &channels,
636 &num_channels);
637 if (ret) {
638 fprintf(stderr, "Problem reading scan element "
639 "information\n"
640 "diag %s\n", dev_dir_name);
641 goto error;
642 }
643 if (!num_channels) {
644 fprintf(stderr, "Still no channels after "
645 "auto-enabling, giving up\n");
646 goto error;
647 }
648 }
649
650 if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
651 fprintf(stderr,
652 "No channels are enabled, we have nothing to scan.\n");
653 fprintf(stderr, "Enable channels manually in "
654 FORMAT_SCAN_ELEMENTS_DIR
655 "/*_en or pass -a to autoenable channels and "
656 "try again.\n", dev_dir_name, buffer_idx);
657 ret = -ENOENT;
658 goto error;
659 }
660
661 /*
662 * Construct the directory name for the associated buffer.
663 * As we know that the lis3l02dq has only one buffer this may
664 * be built rather than found.
665 */
666 ret = asprintf(&buf_dir_name,
667 "%siio:device%d/buffer%d", iio_dir, dev_num, buffer_idx);
668 if (ret < 0) {
669 ret = -ENOMEM;
670 goto error;
671 }
672
673 if (stat(buf_dir_name, &st)) {
674 fprintf(stderr, "Could not stat() '%s', got error %d: %s\n",
675 buf_dir_name, errno, strerror(errno));
676 ret = -errno;
677 goto error;
678 }
679
680 if (!S_ISDIR(st.st_mode)) {
681 fprintf(stderr, "File '%s' is not a directory\n", buf_dir_name);
682 ret = -EFAULT;
683 goto error;
684 }
685
686 if (!notrigger) {
687 printf("%s %s\n", dev_dir_name, trigger_name);
688 /*
689 * Set the device trigger to be the data ready trigger found
690 * above
691 */
692 ret = write_sysfs_string_and_verify("trigger/current_trigger",
693 dev_dir_name,
694 trigger_name);
695 if (ret < 0) {
696 fprintf(stderr,
697 "Failed to write current_trigger file\n");
698 goto error;
699 }
700 }
701
702 ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
703 if (ret < 0) {
704 ret = -ENOMEM;
705 goto error;
706 }
707
708 /* Attempt to open non blocking the access dev */
709 fd = open(buffer_access, O_RDONLY | O_NONBLOCK);
710 if (fd == -1) { /* TODO: If it isn't there make the node */
711 ret = -errno;
712 fprintf(stderr, "Failed to open %s\n", buffer_access);
713 goto error;
714 }
715
716 /* specify for which buffer index we want an FD */
717 buf_fd = buffer_idx;
718
719 ret = ioctl(fd, IIO_BUFFER_GET_FD_IOCTL, &buf_fd);
720 if (ret == -1 || buf_fd == -1) {
721 ret = -errno;
722 if (ret == -ENODEV || ret == -EINVAL)
723 fprintf(stderr,
724 "Device does not have this many buffers\n");
725 else
726 fprintf(stderr, "Failed to retrieve buffer fd\n");
727
728 goto error;
729 }
730
731 /* Setup ring buffer parameters */
732 ret = write_sysfs_int("length", buf_dir_name, buf_len);
733 if (ret < 0)
734 goto error;
735
736 /* Enable the buffer */
737 ret = write_sysfs_int("enable", buf_dir_name, 1);
738 if (ret < 0) {
739 fprintf(stderr,
740 "Failed to enable buffer '%s': %s\n",
741 buf_dir_name, strerror(-ret));
742 goto error;
743 }
744
745 scan_size = size_from_channelarray(channels, num_channels);
746
747 size_t total_buf_len = scan_size * buf_len;
748
749 if (scan_size > 0 && total_buf_len / scan_size != buf_len) {
750 ret = -EFAULT;
751 perror("Integer overflow happened when calculate scan_size * buf_len");
752 goto error;
753 }
754
755 data = malloc(total_buf_len);
756 if (!data) {
757 ret = -ENOMEM;
758 goto error;
759 }
760
761 /**
762 * This check is being done here for sanity reasons, however it
763 * should be omitted under normal operation.
764 * If this is buffer0, we check that we get EBUSY after this point.
765 */
766 if (buffer_idx == 0) {
767 errno = 0;
768 read_size = read(fd, data, 1);
769 if (read_size > -1 || errno != EBUSY) {
770 ret = -EFAULT;
771 perror("Reading from '%s' should not be possible after ioctl()");
772 goto error;
773 }
774 }
775
776 /* close now the main chardev FD and let the buffer FD work */
777 if (close(fd) == -1)
778 perror("Failed to close character device file");
779 fd = -1;
780
781 for (j = 0; j < num_loops || num_loops < 0; j++) {
782 if (!noevents) {
783 struct pollfd pfd = {
784 .fd = buf_fd,
785 .events = POLLIN,
786 };
787
788 ret = poll(&pfd, 1, -1);
789 if (ret < 0) {
790 ret = -errno;
791 goto error;
792 } else if (ret == 0) {
793 continue;
794 }
795
796 } else {
797 usleep(timedelay);
798 }
799
800 toread = buf_len;
801
802 read_size = read(buf_fd, data, toread * scan_size);
803 if (read_size < 0) {
804 if (errno == EAGAIN) {
805 fprintf(stderr, "nothing available\n");
806 continue;
807 } else {
808 break;
809 }
810 }
811 for (i = 0; i < read_size / scan_size; i++)
812 process_scan(data + scan_size * i, channels,
813 num_channels);
814 }
815
816error:
817 cleanup();
818
819 if (fd >= 0 && close(fd) == -1)
820 perror("Failed to close character device");
821 if (buf_fd >= 0 && close(buf_fd) == -1)
822 perror("Failed to close buffer");
823 free(buffer_access);
824 free(data);
825 free(buf_dir_name);
826 for (i = num_channels - 1; i >= 0; i--) {
827 free(channels[i].name);
828 free(channels[i].generic_name);
829 }
830 free(channels);
831 free(trigger_name);
832 free(device_name);
833 free(dev_dir_name);
834
835 return ret;
836}