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-rw-r--r--tools/iio/iio_generic_buffer.c682
1 files changed, 682 insertions, 0 deletions
diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
new file mode 100644
index 000000000000..e8c30521e99c
--- /dev/null
+++ b/tools/iio/iio_generic_buffer.c
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1/* Industrialio buffer test code.
2 *
3 * Copyright (c) 2008 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 * This program is primarily intended as an example application.
10 * Reads the current buffer setup from sysfs and starts a short capture
11 * from the specified device, pretty printing the result after appropriate
12 * conversion.
13 *
14 * Command line parameters
15 * generic_buffer -n <device_name> -t <trigger_name>
16 * If trigger name is not specified the program assumes you want a dataready
17 * trigger associated with the device and goes looking for it.
18 *
19 */
20
21#include <unistd.h>
22#include <stdlib.h>
23#include <dirent.h>
24#include <fcntl.h>
25#include <stdio.h>
26#include <errno.h>
27#include <sys/stat.h>
28#include <sys/dir.h>
29#include <linux/types.h>
30#include <string.h>
31#include <poll.h>
32#include <endian.h>
33#include <getopt.h>
34#include <inttypes.h>
35#include <stdbool.h>
36#include <signal.h>
37#include "iio_utils.h"
38
39/**
40 * enum autochan - state for the automatic channel enabling mechanism
41 */
42enum autochan {
43 AUTOCHANNELS_DISABLED,
44 AUTOCHANNELS_ENABLED,
45 AUTOCHANNELS_ACTIVE,
46};
47
48/**
49 * size_from_channelarray() - calculate the storage size of a scan
50 * @channels: the channel info array
51 * @num_channels: number of channels
52 *
53 * Has the side effect of filling the channels[i].location values used
54 * in processing the buffer output.
55 **/
56int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
57{
58 int bytes = 0;
59 int i = 0;
60
61 while (i < num_channels) {
62 if (bytes % channels[i].bytes == 0)
63 channels[i].location = bytes;
64 else
65 channels[i].location = bytes - bytes % channels[i].bytes
66 + channels[i].bytes;
67
68 bytes = channels[i].location + channels[i].bytes;
69 i++;
70 }
71
72 return bytes;
73}
74
75void print1byte(uint8_t input, struct iio_channel_info *info)
76{
77 /*
78 * Shift before conversion to avoid sign extension
79 * of left aligned data
80 */
81 input >>= info->shift;
82 input &= info->mask;
83 if (info->is_signed) {
84 int8_t val = (int8_t)(input << (8 - info->bits_used)) >>
85 (8 - info->bits_used);
86 printf("%05f ", ((float)val + info->offset) * info->scale);
87 } else {
88 printf("%05f ", ((float)input + info->offset) * info->scale);
89 }
90}
91
92void print2byte(uint16_t input, struct iio_channel_info *info)
93{
94 /* First swap if incorrect endian */
95 if (info->be)
96 input = be16toh(input);
97 else
98 input = le16toh(input);
99
100 /*
101 * Shift before conversion to avoid sign extension
102 * of left aligned data
103 */
104 input >>= info->shift;
105 input &= info->mask;
106 if (info->is_signed) {
107 int16_t val = (int16_t)(input << (16 - info->bits_used)) >>
108 (16 - info->bits_used);
109 printf("%05f ", ((float)val + info->offset) * info->scale);
110 } else {
111 printf("%05f ", ((float)input + info->offset) * info->scale);
112 }
113}
114
115void print4byte(uint32_t input, struct iio_channel_info *info)
116{
117 /* First swap if incorrect endian */
118 if (info->be)
119 input = be32toh(input);
120 else
121 input = le32toh(input);
122
123 /*
124 * Shift before conversion to avoid sign extension
125 * of left aligned data
126 */
127 input >>= info->shift;
128 input &= info->mask;
129 if (info->is_signed) {
130 int32_t val = (int32_t)(input << (32 - info->bits_used)) >>
131 (32 - info->bits_used);
132 printf("%05f ", ((float)val + info->offset) * info->scale);
133 } else {
134 printf("%05f ", ((float)input + info->offset) * info->scale);
135 }
136}
137
138void print8byte(uint64_t input, struct iio_channel_info *info)
139{
140 /* First swap if incorrect endian */
141 if (info->be)
142 input = be64toh(input);
143 else
144 input = le64toh(input);
145
146 /*
147 * Shift before conversion to avoid sign extension
148 * of left aligned data
149 */
150 input >>= info->shift;
151 input &= info->mask;
152 if (info->is_signed) {
153 int64_t val = (int64_t)(input << (64 - info->bits_used)) >>
154 (64 - info->bits_used);
155 /* special case for timestamp */
156 if (info->scale == 1.0f && info->offset == 0.0f)
157 printf("%" PRId64 " ", val);
158 else
159 printf("%05f ",
160 ((float)val + info->offset) * info->scale);
161 } else {
162 printf("%05f ", ((float)input + info->offset) * info->scale);
163 }
164}
165
166/**
167 * process_scan() - print out the values in SI units
168 * @data: pointer to the start of the scan
169 * @channels: information about the channels.
170 * Note: size_from_channelarray must have been called first
171 * to fill the location offsets.
172 * @num_channels: number of channels
173 **/
174void process_scan(char *data,
175 struct iio_channel_info *channels,
176 int num_channels)
177{
178 int k;
179
180 for (k = 0; k < num_channels; k++)
181 switch (channels[k].bytes) {
182 /* only a few cases implemented so far */
183 case 1:
184 print1byte(*(uint8_t *)(data + channels[k].location),
185 &channels[k]);
186 break;
187 case 2:
188 print2byte(*(uint16_t *)(data + channels[k].location),
189 &channels[k]);
190 break;
191 case 4:
192 print4byte(*(uint32_t *)(data + channels[k].location),
193 &channels[k]);
194 break;
195 case 8:
196 print8byte(*(uint64_t *)(data + channels[k].location),
197 &channels[k]);
198 break;
199 default:
200 break;
201 }
202 printf("\n");
203}
204
205static int enable_disable_all_channels(char *dev_dir_name, int enable)
206{
207 const struct dirent *ent;
208 char scanelemdir[256];
209 DIR *dp;
210 int ret;
211
212 snprintf(scanelemdir, sizeof(scanelemdir),
213 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name);
214 scanelemdir[sizeof(scanelemdir)-1] = '\0';
215
216 dp = opendir(scanelemdir);
217 if (!dp) {
218 fprintf(stderr, "Enabling/disabling channels: can't open %s\n",
219 scanelemdir);
220 return -EIO;
221 }
222
223 ret = -ENOENT;
224 while (ent = readdir(dp), ent) {
225 if (iioutils_check_suffix(ent->d_name, "_en")) {
226 printf("%sabling: %s\n",
227 enable ? "En" : "Dis",
228 ent->d_name);
229 ret = write_sysfs_int(ent->d_name, scanelemdir,
230 enable);
231 if (ret < 0)
232 fprintf(stderr, "Failed to enable/disable %s\n",
233 ent->d_name);
234 }
235 }
236
237 if (closedir(dp) == -1) {
238 perror("Enabling/disabling channels: "
239 "Failed to close directory");
240 return -errno;
241 }
242 return 0;
243}
244
245void print_usage(void)
246{
247 fprintf(stderr, "Usage: generic_buffer [options]...\n"
248 "Capture, convert and output data from IIO device buffer\n"
249 " -a Auto-activate all available channels\n"
250 " -c <n> Do n conversions\n"
251 " -e Disable wait for event (new data)\n"
252 " -g Use trigger-less mode\n"
253 " -l <n> Set buffer length to n samples\n"
254 " --device-name -n <name>\n"
255 " --device-num -N <num>\n"
256 " Set device by name or number (mandatory)\n"
257 " --trigger-name -t <name>\n"
258 " --trigger-num -T <num>\n"
259 " Set trigger by name or number\n"
260 " -w <n> Set delay between reads in us (event-less mode)\n");
261}
262
263enum autochan autochannels = AUTOCHANNELS_DISABLED;
264char *dev_dir_name = NULL;
265char *buf_dir_name = NULL;
266bool current_trigger_set = false;
267
268void cleanup(void)
269{
270 int ret;
271
272 /* Disable trigger */
273 if (dev_dir_name && current_trigger_set) {
274 /* Disconnect the trigger - just write a dummy name. */
275 ret = write_sysfs_string("trigger/current_trigger",
276 dev_dir_name, "NULL");
277 if (ret < 0)
278 fprintf(stderr, "Failed to disable trigger: %s\n",
279 strerror(-ret));
280 current_trigger_set = false;
281 }
282
283 /* Disable buffer */
284 if (buf_dir_name) {
285 ret = write_sysfs_int("enable", buf_dir_name, 0);
286 if (ret < 0)
287 fprintf(stderr, "Failed to disable buffer: %s\n",
288 strerror(-ret));
289 }
290
291 /* Disable channels if auto-enabled */
292 if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {
293 ret = enable_disable_all_channels(dev_dir_name, 0);
294 if (ret)
295 fprintf(stderr, "Failed to disable all channels\n");
296 autochannels = AUTOCHANNELS_DISABLED;
297 }
298}
299
300void sig_handler(int signum)
301{
302 fprintf(stderr, "Caught signal %d\n", signum);
303 cleanup();
304 exit(-signum);
305}
306
307void register_cleanup(void)
308{
309 struct sigaction sa = { .sa_handler = sig_handler };
310 const int signums[] = { SIGINT, SIGTERM, SIGABRT };
311 int ret, i;
312
313 for (i = 0; i < ARRAY_SIZE(signums); ++i) {
314 ret = sigaction(signums[i], &sa, NULL);
315 if (ret) {
316 perror("Failed to register signal handler");
317 exit(-1);
318 }
319 }
320}
321
322static const struct option longopts[] = {
323 { "device-name", 1, 0, 'n' },
324 { "device-num", 1, 0, 'N' },
325 { "trigger-name", 1, 0, 't' },
326 { "trigger-num", 1, 0, 'T' },
327 { },
328};
329
330int main(int argc, char **argv)
331{
332 unsigned long num_loops = 2;
333 unsigned long timedelay = 1000000;
334 unsigned long buf_len = 128;
335
336 int ret, c, i, j, toread;
337 int fp = -1;
338
339 int num_channels = 0;
340 char *trigger_name = NULL, *device_name = NULL;
341
342 char *data = NULL;
343 ssize_t read_size;
344 int dev_num = -1, trig_num;
345 char *buffer_access = NULL;
346 int scan_size;
347 int noevents = 0;
348 int notrigger = 0;
349 char *dummy;
350
351 struct iio_channel_info *channels;
352
353 register_cleanup();
354
355 while ((c = getopt_long(argc, argv, "ac:egl:n:N:t:T:w:", longopts, NULL)) != -1) {
356 switch (c) {
357 case 'a':
358 autochannels = AUTOCHANNELS_ENABLED;
359 break;
360 case 'c':
361 errno = 0;
362 num_loops = strtoul(optarg, &dummy, 10);
363 if (errno) {
364 ret = -errno;
365 goto error;
366 }
367
368 break;
369 case 'e':
370 noevents = 1;
371 break;
372 case 'g':
373 notrigger = 1;
374 break;
375 case 'l':
376 errno = 0;
377 buf_len = strtoul(optarg, &dummy, 10);
378 if (errno) {
379 ret = -errno;
380 goto error;
381 }
382
383 break;
384 case 'n':
385 device_name = strdup(optarg);
386 break;
387 case 'N':
388 errno = 0;
389 dev_num = strtoul(optarg, &dummy, 10);
390 if (errno) {
391 ret = -errno;
392 goto error;
393 }
394 break;
395 case 't':
396 trigger_name = strdup(optarg);
397 break;
398 case 'T':
399 errno = 0;
400 trig_num = strtoul(optarg, &dummy, 10);
401 if (errno)
402 return -errno;
403 break;
404 case 'w':
405 errno = 0;
406 timedelay = strtoul(optarg, &dummy, 10);
407 if (errno) {
408 ret = -errno;
409 goto error;
410 }
411 break;
412 case '?':
413 print_usage();
414 ret = -1;
415 goto error;
416 }
417 }
418
419 /* Find the device requested */
420 if (dev_num < 0 && !device_name) {
421 fprintf(stderr, "Device not set\n");
422 print_usage();
423 ret = -1;
424 goto error;
425 } else if (dev_num >= 0 && device_name) {
426 fprintf(stderr, "Only one of --device-num or --device-name needs to be set\n");
427 print_usage();
428 ret = -1;
429 goto error;
430 } else if (dev_num < 0) {
431 dev_num = find_type_by_name(device_name, "iio:device");
432 if (dev_num < 0) {
433 fprintf(stderr, "Failed to find the %s\n", device_name);
434 ret = dev_num;
435 goto error;
436 }
437 }
438 printf("iio device number being used is %d\n", dev_num);
439
440 ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
441 if (ret < 0)
442 return -ENOMEM;
443 /* Fetch device_name if specified by number */
444 if (!device_name) {
445 device_name = malloc(IIO_MAX_NAME_LENGTH);
446 if (!device_name) {
447 ret = -ENOMEM;
448 goto error;
449 }
450 ret = read_sysfs_string("name", dev_dir_name, device_name);
451 if (ret < 0) {
452 fprintf(stderr, "Failed to read name of device %d\n", dev_num);
453 goto error;
454 }
455 }
456
457 if (notrigger) {
458 printf("trigger-less mode selected\n");
459 } if (trig_num > 0) {
460 char *trig_dev_name;
461 ret = asprintf(&trig_dev_name, "%strigger%d", iio_dir, trig_num);
462 if (ret < 0) {
463 return -ENOMEM;
464 }
465 trigger_name = malloc(IIO_MAX_NAME_LENGTH);
466 ret = read_sysfs_string("name", trig_dev_name, trigger_name);
467 free(trig_dev_name);
468 if (ret < 0) {
469 fprintf(stderr, "Failed to read trigger%d name from\n", trig_num);
470 return ret;
471 }
472 printf("iio trigger number being used is %d\n", trig_num);
473 } else {
474 if (!trigger_name) {
475 /*
476 * Build the trigger name. If it is device associated
477 * its name is <device_name>_dev[n] where n matches
478 * the device number found above.
479 */
480 ret = asprintf(&trigger_name,
481 "%s-dev%d", device_name, dev_num);
482 if (ret < 0) {
483 ret = -ENOMEM;
484 goto error;
485 }
486 }
487
488 /* Look for this "-devN" trigger */
489 trig_num = find_type_by_name(trigger_name, "trigger");
490 if (trig_num < 0) {
491 /* OK try the simpler "-trigger" suffix instead */
492 free(trigger_name);
493 ret = asprintf(&trigger_name,
494 "%s-trigger", device_name);
495 if (ret < 0) {
496 ret = -ENOMEM;
497 goto error;
498 }
499 }
500
501 trig_num = find_type_by_name(trigger_name, "trigger");
502 if (trig_num < 0) {
503 fprintf(stderr, "Failed to find the trigger %s\n",
504 trigger_name);
505 ret = trig_num;
506 goto error;
507 }
508
509 printf("iio trigger number being used is %d\n", trig_num);
510 }
511
512 /*
513 * Parse the files in scan_elements to identify what channels are
514 * present
515 */
516 ret = build_channel_array(dev_dir_name, &channels, &num_channels);
517 if (ret) {
518 fprintf(stderr, "Problem reading scan element information\n"
519 "diag %s\n", dev_dir_name);
520 goto error;
521 }
522 if (num_channels && autochannels == AUTOCHANNELS_ENABLED) {
523 fprintf(stderr, "Auto-channels selected but some channels "
524 "are already activated in sysfs\n");
525 fprintf(stderr, "Proceeding without activating any channels\n");
526 }
527
528 if (!num_channels && autochannels == AUTOCHANNELS_ENABLED) {
529 fprintf(stderr,
530 "No channels are enabled, enabling all channels\n");
531
532 ret = enable_disable_all_channels(dev_dir_name, 1);
533 if (ret) {
534 fprintf(stderr, "Failed to enable all channels\n");
535 goto error;
536 }
537
538 /* This flags that we need to disable the channels again */
539 autochannels = AUTOCHANNELS_ACTIVE;
540
541 ret = build_channel_array(dev_dir_name, &channels,
542 &num_channels);
543 if (ret) {
544 fprintf(stderr, "Problem reading scan element "
545 "information\n"
546 "diag %s\n", dev_dir_name);
547 goto error;
548 }
549 if (!num_channels) {
550 fprintf(stderr, "Still no channels after "
551 "auto-enabling, giving up\n");
552 goto error;
553 }
554 }
555
556 if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
557 fprintf(stderr,
558 "No channels are enabled, we have nothing to scan.\n");
559 fprintf(stderr, "Enable channels manually in "
560 FORMAT_SCAN_ELEMENTS_DIR
561 "/*_en or pass -a to autoenable channels and "
562 "try again.\n", dev_dir_name);
563 ret = -ENOENT;
564 goto error;
565 }
566
567 /*
568 * Construct the directory name for the associated buffer.
569 * As we know that the lis3l02dq has only one buffer this may
570 * be built rather than found.
571 */
572 ret = asprintf(&buf_dir_name,
573 "%siio:device%d/buffer", iio_dir, dev_num);
574 if (ret < 0) {
575 ret = -ENOMEM;
576 goto error;
577 }
578
579 if (!notrigger) {
580 printf("%s %s\n", dev_dir_name, trigger_name);
581 /*
582 * Set the device trigger to be the data ready trigger found
583 * above
584 */
585 ret = write_sysfs_string_and_verify("trigger/current_trigger",
586 dev_dir_name,
587 trigger_name);
588 if (ret < 0) {
589 fprintf(stderr,
590 "Failed to write current_trigger file\n");
591 goto error;
592 }
593 }
594
595 /* Setup ring buffer parameters */
596 ret = write_sysfs_int("length", buf_dir_name, buf_len);
597 if (ret < 0)
598 goto error;
599
600 /* Enable the buffer */
601 ret = write_sysfs_int("enable", buf_dir_name, 1);
602 if (ret < 0) {
603 fprintf(stderr,
604 "Failed to enable buffer: %s\n", strerror(-ret));
605 goto error;
606 }
607
608 scan_size = size_from_channelarray(channels, num_channels);
609 data = malloc(scan_size * buf_len);
610 if (!data) {
611 ret = -ENOMEM;
612 goto error;
613 }
614
615 ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
616 if (ret < 0) {
617 ret = -ENOMEM;
618 goto error;
619 }
620
621 /* Attempt to open non blocking the access dev */
622 fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
623 if (fp == -1) { /* TODO: If it isn't there make the node */
624 ret = -errno;
625 fprintf(stderr, "Failed to open %s\n", buffer_access);
626 goto error;
627 }
628
629 for (j = 0; j < num_loops; j++) {
630 if (!noevents) {
631 struct pollfd pfd = {
632 .fd = fp,
633 .events = POLLIN,
634 };
635
636 ret = poll(&pfd, 1, -1);
637 if (ret < 0) {
638 ret = -errno;
639 goto error;
640 } else if (ret == 0) {
641 continue;
642 }
643
644 toread = buf_len;
645 } else {
646 usleep(timedelay);
647 toread = 64;
648 }
649
650 read_size = read(fp, data, toread * scan_size);
651 if (read_size < 0) {
652 if (errno == EAGAIN) {
653 fprintf(stderr, "nothing available\n");
654 continue;
655 } else {
656 break;
657 }
658 }
659 for (i = 0; i < read_size / scan_size; i++)
660 process_scan(data + scan_size * i, channels,
661 num_channels);
662 }
663
664error:
665 cleanup();
666
667 if (fp >= 0 && close(fp) == -1)
668 perror("Failed to close buffer");
669 free(buffer_access);
670 free(data);
671 free(buf_dir_name);
672 for (i = num_channels - 1; i >= 0; i--) {
673 free(channels[i].name);
674 free(channels[i].generic_name);
675 }
676 free(channels);
677 free(trigger_name);
678 free(device_name);
679 free(dev_dir_name);
680
681 return ret;
682}
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-25 07:08:00 -0400