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v4.10.11
 
  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		"  -A         Force-activate ALL channels\n"
251		"  -c <n>     Do n conversions\n"
 
252		"  -e         Disable wait for event (new data)\n"
253		"  -g         Use trigger-less mode\n"
254		"  -l <n>     Set buffer length to n samples\n"
255		"  --device-name -n <name>\n"
256		"  --device-num -N <num>\n"
257		"        Set device by name or number (mandatory)\n"
258		"  --trigger-name -t <name>\n"
259		"  --trigger-num -T <num>\n"
260		"        Set trigger by name or number\n"
261		"  -w <n>     Set delay between reads in us (event-less mode)\n");
262}
263
264enum autochan autochannels = AUTOCHANNELS_DISABLED;
265char *dev_dir_name = NULL;
266char *buf_dir_name = NULL;
267bool current_trigger_set = false;
 
268
269void cleanup(void)
270{
271	int ret;
272
273	/* Disable trigger */
274	if (dev_dir_name && current_trigger_set) {
275		/* Disconnect the trigger - just write a dummy name. */
276		ret = write_sysfs_string("trigger/current_trigger",
277					 dev_dir_name, "NULL");
278		if (ret < 0)
279			fprintf(stderr, "Failed to disable trigger: %s\n",
280				strerror(-ret));
281		current_trigger_set = false;
282	}
283
284	/* Disable buffer */
285	if (buf_dir_name) {
286		ret = write_sysfs_int("enable", buf_dir_name, 0);
287		if (ret < 0)
288			fprintf(stderr, "Failed to disable buffer: %s\n",
289				strerror(-ret));
290	}
291
292	/* Disable channels if auto-enabled */
293	if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {
294		ret = enable_disable_all_channels(dev_dir_name, 0);
295		if (ret)
296			fprintf(stderr, "Failed to disable all channels\n");
297		autochannels = AUTOCHANNELS_DISABLED;
298	}
299}
300
301void sig_handler(int signum)
302{
303	fprintf(stderr, "Caught signal %d\n", signum);
304	cleanup();
305	exit(-signum);
306}
307
308void register_cleanup(void)
309{
310	struct sigaction sa = { .sa_handler = sig_handler };
311	const int signums[] = { SIGINT, SIGTERM, SIGABRT };
312	int ret, i;
313
314	for (i = 0; i < ARRAY_SIZE(signums); ++i) {
315		ret = sigaction(signums[i], &sa, NULL);
316		if (ret) {
317			perror("Failed to register signal handler");
318			exit(-1);
319		}
320	}
321}
322
323static const struct option longopts[] = {
324	{ "device-name",	1, 0, 'n' },
325	{ "device-num",		1, 0, 'N' },
326	{ "trigger-name",	1, 0, 't' },
327	{ "trigger-num",	1, 0, 'T' },
328	{ },
329};
330
331int main(int argc, char **argv)
332{
333	unsigned long num_loops = 2;
334	unsigned long timedelay = 1000000;
335	unsigned long buf_len = 128;
336
337	int ret, c, i, j, toread;
338	int fp = -1;
 
 
 
 
 
339
340	int num_channels = 0;
341	char *trigger_name = NULL, *device_name = NULL;
342
343	char *data = NULL;
344	ssize_t read_size;
345	int dev_num = -1, trig_num = -1;
346	char *buffer_access = NULL;
347	int scan_size;
348	int noevents = 0;
349	int notrigger = 0;
350	char *dummy;
351	bool force_autochannels = false;
352
353	struct iio_channel_info *channels = NULL;
354
355	register_cleanup();
356
357	while ((c = getopt_long(argc, argv, "aAc:egl:n:N:t:T:w:?", longopts,
358				NULL)) != -1) {
359		switch (c) {
360		case 'a':
361			autochannels = AUTOCHANNELS_ENABLED;
362			break;
363		case 'A':
364			autochannels = AUTOCHANNELS_ENABLED;
365			force_autochannels = true;
366			break;	
 
 
 
 
 
 
 
 
 
 
 
 
 
367		case 'c':
368			errno = 0;
369			num_loops = strtoul(optarg, &dummy, 10);
370			if (errno) {
371				ret = -errno;
372				goto error;
373			}
374
375			break;
376		case 'e':
377			noevents = 1;
378			break;
379		case 'g':
380			notrigger = 1;
381			break;
382		case 'l':
383			errno = 0;
384			buf_len = strtoul(optarg, &dummy, 10);
385			if (errno) {
386				ret = -errno;
387				goto error;
388			}
389
390			break;
391		case 'n':
392			device_name = strdup(optarg);
393			break;
394		case 'N':
395			errno = 0;
396			dev_num = strtoul(optarg, &dummy, 10);
397			if (errno) {
398				ret = -errno;
399				goto error;
400			}
401			break;
402		case 't':
403			trigger_name = strdup(optarg);
404			break;
405		case 'T':
406			errno = 0;
407			trig_num = strtoul(optarg, &dummy, 10);
408			if (errno)
409				return -errno;
410			break;
411		case 'w':
412			errno = 0;
413			timedelay = strtoul(optarg, &dummy, 10);
414			if (errno) {
415				ret = -errno;
416				goto error;
417			}
418			break;
419		case '?':
420			print_usage();
421			ret = -1;
422			goto error;
423		}
424	}
425
426	/* Find the device requested */
427	if (dev_num < 0 && !device_name) {
428		fprintf(stderr, "Device not set\n");
429		print_usage();
430		ret = -1;
431		goto error;
432	} else if (dev_num >= 0 && device_name) {
433		fprintf(stderr, "Only one of --device-num or --device-name needs to be set\n");
434		print_usage();
435		ret = -1;
436		goto error;
437	} else if (dev_num < 0) {
438		dev_num = find_type_by_name(device_name, "iio:device");
439		if (dev_num < 0) {
440			fprintf(stderr, "Failed to find the %s\n", device_name);
441			ret = dev_num;
442			goto error;
443		}
444	}
445	printf("iio device number being used is %d\n", dev_num);
446
447	ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
448	if (ret < 0)
449		return -ENOMEM;
450	/* Fetch device_name if specified by number */
451	if (!device_name) {
452		device_name = malloc(IIO_MAX_NAME_LENGTH);
453		if (!device_name) {
454			ret = -ENOMEM;
455			goto error;
456		}
457		ret = read_sysfs_string("name", dev_dir_name, device_name);
458		if (ret < 0) {
459			fprintf(stderr, "Failed to read name of device %d\n", dev_num);
460			goto error;
461		}
462	}
463
464	if (notrigger) {
465		printf("trigger-less mode selected\n");
466	} else if (trig_num >= 0) {
467		char *trig_dev_name;
468		ret = asprintf(&trig_dev_name, "%strigger%d", iio_dir, trig_num);
469		if (ret < 0) {
470			return -ENOMEM;
471		}
472		trigger_name = malloc(IIO_MAX_NAME_LENGTH);
473		ret = read_sysfs_string("name", trig_dev_name, trigger_name);
474		free(trig_dev_name);
475		if (ret < 0) {
476			fprintf(stderr, "Failed to read trigger%d name from\n", trig_num);
477			return ret;
478		}
479		printf("iio trigger number being used is %d\n", trig_num);
480	} else {
481		if (!trigger_name) {
482			/*
483			 * Build the trigger name. If it is device associated
484			 * its name is <device_name>_dev[n] where n matches
485			 * the device number found above.
486			 */
487			ret = asprintf(&trigger_name,
488				       "%s-dev%d", device_name, dev_num);
489			if (ret < 0) {
490				ret = -ENOMEM;
491				goto error;
492			}
493		}
494
495		/* Look for this "-devN" trigger */
496		trig_num = find_type_by_name(trigger_name, "trigger");
497		if (trig_num < 0) {
498			/* OK try the simpler "-trigger" suffix instead */
499			free(trigger_name);
500			ret = asprintf(&trigger_name,
501				       "%s-trigger", device_name);
502			if (ret < 0) {
503				ret = -ENOMEM;
504				goto error;
505			}
506		}
507
508		trig_num = find_type_by_name(trigger_name, "trigger");
509		if (trig_num < 0) {
510			fprintf(stderr, "Failed to find the trigger %s\n",
511				trigger_name);
512			ret = trig_num;
513			goto error;
514		}
515
516		printf("iio trigger number being used is %d\n", trig_num);
517	}
518
519	/*
520	 * Parse the files in scan_elements to identify what channels are
521	 * present
522	 */
523	ret = build_channel_array(dev_dir_name, &channels, &num_channels);
524	if (ret) {
525		fprintf(stderr, "Problem reading scan element information\n"
526			"diag %s\n", dev_dir_name);
527		goto error;
528	}
529	if (num_channels && autochannels == AUTOCHANNELS_ENABLED &&
530	    !force_autochannels) {
531		fprintf(stderr, "Auto-channels selected but some channels "
532			"are already activated in sysfs\n");
533		fprintf(stderr, "Proceeding without activating any channels\n");
534	}
535
536	if ((!num_channels && autochannels == AUTOCHANNELS_ENABLED) ||
537	    (autochannels == AUTOCHANNELS_ENABLED && force_autochannels)) {
538		fprintf(stderr, "Enabling all channels\n");
539
540		ret = enable_disable_all_channels(dev_dir_name, 1);
541		if (ret) {
542			fprintf(stderr, "Failed to enable all channels\n");
543			goto error;
544		}
545
546		/* This flags that we need to disable the channels again */
547		autochannels = AUTOCHANNELS_ACTIVE;
548
549		ret = build_channel_array(dev_dir_name, &channels,
550					  &num_channels);
551		if (ret) {
552			fprintf(stderr, "Problem reading scan element "
553				"information\n"
554				"diag %s\n", dev_dir_name);
555			goto error;
556		}
557		if (!num_channels) {
558			fprintf(stderr, "Still no channels after "
559				"auto-enabling, giving up\n");
560			goto error;
561		}
562	}
563
564	if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
565		fprintf(stderr,
566			"No channels are enabled, we have nothing to scan.\n");
567		fprintf(stderr, "Enable channels manually in "
568			FORMAT_SCAN_ELEMENTS_DIR
569			"/*_en or pass -a to autoenable channels and "
570			"try again.\n", dev_dir_name);
571		ret = -ENOENT;
572		goto error;
573	}
574
575	/*
576	 * Construct the directory name for the associated buffer.
577	 * As we know that the lis3l02dq has only one buffer this may
578	 * be built rather than found.
579	 */
580	ret = asprintf(&buf_dir_name,
581		       "%siio:device%d/buffer", iio_dir, dev_num);
582	if (ret < 0) {
583		ret = -ENOMEM;
584		goto error;
585	}
586
 
 
 
 
 
 
 
 
 
 
 
 
 
587	if (!notrigger) {
588		printf("%s %s\n", dev_dir_name, trigger_name);
589		/*
590		 * Set the device trigger to be the data ready trigger found
591		 * above
592		 */
593		ret = write_sysfs_string_and_verify("trigger/current_trigger",
594						    dev_dir_name,
595						    trigger_name);
596		if (ret < 0) {
597			fprintf(stderr,
598				"Failed to write current_trigger file\n");
599			goto error;
600		}
601	}
602
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
603	/* Setup ring buffer parameters */
604	ret = write_sysfs_int("length", buf_dir_name, buf_len);
605	if (ret < 0)
606		goto error;
607
608	/* Enable the buffer */
609	ret = write_sysfs_int("enable", buf_dir_name, 1);
610	if (ret < 0) {
611		fprintf(stderr,
612			"Failed to enable buffer: %s\n", strerror(-ret));
 
613		goto error;
614	}
615
616	scan_size = size_from_channelarray(channels, num_channels);
617	data = malloc(scan_size * buf_len);
618	if (!data) {
619		ret = -ENOMEM;
620		goto error;
621	}
622
623	ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
624	if (ret < 0) {
625		ret = -ENOMEM;
626		goto error;
 
 
 
 
 
 
 
 
 
627	}
628
629	/* Attempt to open non blocking the access dev */
630	fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
631	if (fp == -1) { /* TODO: If it isn't there make the node */
632		ret = -errno;
633		fprintf(stderr, "Failed to open %s\n", buffer_access);
634		goto error;
635	}
636
637	for (j = 0; j < num_loops; j++) {
638		if (!noevents) {
639			struct pollfd pfd = {
640				.fd = fp,
641				.events = POLLIN,
642			};
643
644			ret = poll(&pfd, 1, -1);
645			if (ret < 0) {
646				ret = -errno;
647				goto error;
648			} else if (ret == 0) {
649				continue;
650			}
651
652			toread = buf_len;
653		} else {
654			usleep(timedelay);
655			toread = 64;
656		}
657
658		read_size = read(fp, data, toread * scan_size);
659		if (read_size < 0) {
660			if (errno == EAGAIN) {
661				fprintf(stderr, "nothing available\n");
662				continue;
663			} else {
664				break;
665			}
666		}
667		for (i = 0; i < read_size / scan_size; i++)
668			process_scan(data + scan_size * i, channels,
669				     num_channels);
670	}
671
672error:
673	cleanup();
674
675	if (fp >= 0 && close(fp) == -1)
 
 
676		perror("Failed to close buffer");
677	free(buffer_access);
678	free(data);
679	free(buf_dir_name);
680	for (i = num_channels - 1; i >= 0; i--) {
681		free(channels[i].name);
682		free(channels[i].generic_name);
683	}
684	free(channels);
685	free(trigger_name);
686	free(device_name);
687	free(dev_dir_name);
688
689	return ret;
690}
v5.14.15
  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 <getopt.h>
 30#include <inttypes.h>
 31#include <stdbool.h>
 32#include <signal.h>
 33#include <sys/ioctl.h>
 34#include <linux/iio/buffer.h>
 35#include "iio_utils.h"
 36
 37/**
 38 * enum autochan - state for the automatic channel enabling mechanism
 39 */
 40enum autochan {
 41	AUTOCHANNELS_DISABLED,
 42	AUTOCHANNELS_ENABLED,
 43	AUTOCHANNELS_ACTIVE,
 44};
 45
 46/**
 47 * size_from_channelarray() - calculate the storage size of a scan
 48 * @channels:		the channel info array
 49 * @num_channels:	number of channels
 50 *
 51 * Has the side effect of filling the channels[i].location values used
 52 * in processing the buffer output.
 53 **/
 54static int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
 55{
 56	int bytes = 0;
 57	int i = 0;
 58
 59	while (i < num_channels) {
 60		if (bytes % channels[i].bytes == 0)
 61			channels[i].location = bytes;
 62		else
 63			channels[i].location = bytes - bytes % channels[i].bytes
 64					       + channels[i].bytes;
 65
 66		bytes = channels[i].location + channels[i].bytes;
 67		i++;
 68	}
 69
 70	return bytes;
 71}
 72
 73static void print1byte(uint8_t input, struct iio_channel_info *info)
 74{
 75	/*
 76	 * Shift before conversion to avoid sign extension
 77	 * of left aligned data
 78	 */
 79	input >>= info->shift;
 80	input &= info->mask;
 81	if (info->is_signed) {
 82		int8_t val = (int8_t)(input << (8 - info->bits_used)) >>
 83			     (8 - info->bits_used);
 84		printf("%05f ", ((float)val + info->offset) * info->scale);
 85	} else {
 86		printf("%05f ", ((float)input + info->offset) * info->scale);
 87	}
 88}
 89
 90static void print2byte(uint16_t input, struct iio_channel_info *info)
 91{
 92	/* First swap if incorrect endian */
 93	if (info->be)
 94		input = be16toh(input);
 95	else
 96		input = le16toh(input);
 97
 98	/*
 99	 * Shift before conversion to avoid sign extension
100	 * of left aligned data
101	 */
102	input >>= info->shift;
103	input &= info->mask;
104	if (info->is_signed) {
105		int16_t val = (int16_t)(input << (16 - info->bits_used)) >>
106			      (16 - info->bits_used);
107		printf("%05f ", ((float)val + info->offset) * info->scale);
108	} else {
109		printf("%05f ", ((float)input + info->offset) * info->scale);
110	}
111}
112
113static void print4byte(uint32_t input, struct iio_channel_info *info)
114{
115	/* First swap if incorrect endian */
116	if (info->be)
117		input = be32toh(input);
118	else
119		input = le32toh(input);
120
121	/*
122	 * Shift before conversion to avoid sign extension
123	 * of left aligned data
124	 */
125	input >>= info->shift;
126	input &= info->mask;
127	if (info->is_signed) {
128		int32_t val = (int32_t)(input << (32 - info->bits_used)) >>
129			      (32 - info->bits_used);
130		printf("%05f ", ((float)val + info->offset) * info->scale);
131	} else {
132		printf("%05f ", ((float)input + info->offset) * info->scale);
133	}
134}
135
136static void print8byte(uint64_t input, struct iio_channel_info *info)
137{
138	/* First swap if incorrect endian */
139	if (info->be)
140		input = be64toh(input);
141	else
142		input = le64toh(input);
143
144	/*
145	 * Shift before conversion to avoid sign extension
146	 * of left aligned data
147	 */
148	input >>= info->shift;
149	input &= info->mask;
150	if (info->is_signed) {
151		int64_t val = (int64_t)(input << (64 - info->bits_used)) >>
152			      (64 - info->bits_used);
153		/* special case for timestamp */
154		if (info->scale == 1.0f && info->offset == 0.0f)
155			printf("%" PRId64 " ", val);
156		else
157			printf("%05f ",
158			       ((float)val + info->offset) * info->scale);
159	} else {
160		printf("%05f ", ((float)input + info->offset) * info->scale);
161	}
162}
163
164/**
165 * process_scan() - print out the values in SI units
166 * @data:		pointer to the start of the scan
167 * @channels:		information about the channels.
168 *			Note: size_from_channelarray must have been called first
169 *			      to fill the location offsets.
170 * @num_channels:	number of channels
171 **/
172static void process_scan(char *data, struct iio_channel_info *channels,
173			 int num_channels)
 
174{
175	int k;
176
177	for (k = 0; k < num_channels; k++)
178		switch (channels[k].bytes) {
179			/* only a few cases implemented so far */
180		case 1:
181			print1byte(*(uint8_t *)(data + channels[k].location),
182				   &channels[k]);
183			break;
184		case 2:
185			print2byte(*(uint16_t *)(data + channels[k].location),
186				   &channels[k]);
187			break;
188		case 4:
189			print4byte(*(uint32_t *)(data + channels[k].location),
190				   &channels[k]);
191			break;
192		case 8:
193			print8byte(*(uint64_t *)(data + channels[k].location),
194				   &channels[k]);
195			break;
196		default:
197			break;
198		}
199	printf("\n");
200}
201
202static int enable_disable_all_channels(char *dev_dir_name, int buffer_idx, int enable)
203{
204	const struct dirent *ent;
205	char scanelemdir[256];
206	DIR *dp;
207	int ret;
208
209	snprintf(scanelemdir, sizeof(scanelemdir),
210		 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name, buffer_idx);
211	scanelemdir[sizeof(scanelemdir)-1] = '\0';
212
213	dp = opendir(scanelemdir);
214	if (!dp) {
215		fprintf(stderr, "Enabling/disabling channels: can't open %s\n",
216			scanelemdir);
217		return -EIO;
218	}
219
220	ret = -ENOENT;
221	while (ent = readdir(dp), ent) {
222		if (iioutils_check_suffix(ent->d_name, "_en")) {
223			printf("%sabling: %s\n",
224			       enable ? "En" : "Dis",
225			       ent->d_name);
226			ret = write_sysfs_int(ent->d_name, scanelemdir,
227					      enable);
228			if (ret < 0)
229				fprintf(stderr, "Failed to enable/disable %s\n",
230					ent->d_name);
231		}
232	}
233
234	if (closedir(dp) == -1) {
235		perror("Enabling/disabling channels: "
236		       "Failed to close directory");
237		return -errno;
238	}
239	return 0;
240}
241
242static void print_usage(void)
243{
244	fprintf(stderr, "Usage: generic_buffer [options]...\n"
245		"Capture, convert and output data from IIO device buffer\n"
246		"  -a         Auto-activate all available channels\n"
247		"  -A         Force-activate ALL channels\n"
248		"  -b <n>     The buffer which to open (by index), default 0\n"
249		"  -c <n>     Do n conversions, or loop forever if n < 0\n"
250		"  -e         Disable wait for event (new data)\n"
251		"  -g         Use trigger-less mode\n"
252		"  -l <n>     Set buffer length to n samples\n"
253		"  --device-name -n <name>\n"
254		"  --device-num -N <num>\n"
255		"        Set device by name or number (mandatory)\n"
256		"  --trigger-name -t <name>\n"
257		"  --trigger-num -T <num>\n"
258		"        Set trigger by name or number\n"
259		"  -w <n>     Set delay between reads in us (event-less mode)\n");
260}
261
262static enum autochan autochannels = AUTOCHANNELS_DISABLED;
263static char *dev_dir_name = NULL;
264static char *buf_dir_name = NULL;
265static int buffer_idx = 0;
266static bool current_trigger_set = false;
267
268static void 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, buffer_idx, 0);
294		if (ret)
295			fprintf(stderr, "Failed to disable all channels\n");
296		autochannels = AUTOCHANNELS_DISABLED;
297	}
298}
299
300static void sig_handler(int signum)
301{
302	fprintf(stderr, "Caught signal %d\n", signum);
303	cleanup();
304	exit(-signum);
305}
306
307static void 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	long long num_loops = 2;
333	unsigned long timedelay = 1000000;
334	unsigned long buf_len = 128;
335
336	ssize_t i;
337	unsigned long long j;
338	unsigned long toread;
339	int ret, c;
340	struct stat st;
341	int fd = -1;
342	int buf_fd = -1;
343
344	int num_channels = 0;
345	char *trigger_name = NULL, *device_name = NULL;
346
347	char *data = NULL;
348	ssize_t read_size;
349	int dev_num = -1, trig_num = -1;
350	char *buffer_access = NULL;
351	int scan_size;
352	int noevents = 0;
353	int notrigger = 0;
354	char *dummy;
355	bool force_autochannels = false;
356
357	struct iio_channel_info *channels = NULL;
358
359	register_cleanup();
360
361	while ((c = getopt_long(argc, argv, "aAb:c:egl:n:N:t:T:w:?", longopts,
362				NULL)) != -1) {
363		switch (c) {
364		case 'a':
365			autochannels = AUTOCHANNELS_ENABLED;
366			break;
367		case 'A':
368			autochannels = AUTOCHANNELS_ENABLED;
369			force_autochannels = true;
370			break;
371		case 'b':
372			errno = 0;
373			buffer_idx = strtoll(optarg, &dummy, 10);
374			if (errno) {
375				ret = -errno;
376				goto error;
377			}
378			if (buffer_idx < 0) {
379				ret = -ERANGE;
380				goto error;
381			}
382
383			break;
384		case 'c':
385			errno = 0;
386			num_loops = strtoll(optarg, &dummy, 10);
387			if (errno) {
388				ret = -errno;
389				goto error;
390			}
391
392			break;
393		case 'e':
394			noevents = 1;
395			break;
396		case 'g':
397			notrigger = 1;
398			break;
399		case 'l':
400			errno = 0;
401			buf_len = strtoul(optarg, &dummy, 10);
402			if (errno) {
403				ret = -errno;
404				goto error;
405			}
406
407			break;
408		case 'n':
409			device_name = strdup(optarg);
410			break;
411		case 'N':
412			errno = 0;
413			dev_num = strtoul(optarg, &dummy, 10);
414			if (errno) {
415				ret = -errno;
416				goto error;
417			}
418			break;
419		case 't':
420			trigger_name = strdup(optarg);
421			break;
422		case 'T':
423			errno = 0;
424			trig_num = strtoul(optarg, &dummy, 10);
425			if (errno)
426				return -errno;
427			break;
428		case 'w':
429			errno = 0;
430			timedelay = strtoul(optarg, &dummy, 10);
431			if (errno) {
432				ret = -errno;
433				goto error;
434			}
435			break;
436		case '?':
437			print_usage();
438			ret = -1;
439			goto error;
440		}
441	}
442
443	/* Find the device requested */
444	if (dev_num < 0 && !device_name) {
445		fprintf(stderr, "Device not set\n");
446		print_usage();
447		ret = -1;
448		goto error;
449	} else if (dev_num >= 0 && device_name) {
450		fprintf(stderr, "Only one of --device-num or --device-name needs to be set\n");
451		print_usage();
452		ret = -1;
453		goto error;
454	} else if (dev_num < 0) {
455		dev_num = find_type_by_name(device_name, "iio:device");
456		if (dev_num < 0) {
457			fprintf(stderr, "Failed to find the %s\n", device_name);
458			ret = dev_num;
459			goto error;
460		}
461	}
462	printf("iio device number being used is %d\n", dev_num);
463
464	ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
465	if (ret < 0)
466		return -ENOMEM;
467	/* Fetch device_name if specified by number */
468	if (!device_name) {
469		device_name = malloc(IIO_MAX_NAME_LENGTH);
470		if (!device_name) {
471			ret = -ENOMEM;
472			goto error;
473		}
474		ret = read_sysfs_string("name", dev_dir_name, device_name);
475		if (ret < 0) {
476			fprintf(stderr, "Failed to read name of device %d\n", dev_num);
477			goto error;
478		}
479	}
480
481	if (notrigger) {
482		printf("trigger-less mode selected\n");
483	} else if (trig_num >= 0) {
484		char *trig_dev_name;
485		ret = asprintf(&trig_dev_name, "%strigger%d", iio_dir, trig_num);
486		if (ret < 0) {
487			return -ENOMEM;
488		}
489		trigger_name = malloc(IIO_MAX_NAME_LENGTH);
490		ret = read_sysfs_string("name", trig_dev_name, trigger_name);
491		free(trig_dev_name);
492		if (ret < 0) {
493			fprintf(stderr, "Failed to read trigger%d name from\n", trig_num);
494			return ret;
495		}
496		printf("iio trigger number being used is %d\n", trig_num);
497	} else {
498		if (!trigger_name) {
499			/*
500			 * Build the trigger name. If it is device associated
501			 * its name is <device_name>_dev[n] where n matches
502			 * the device number found above.
503			 */
504			ret = asprintf(&trigger_name,
505				       "%s-dev%d", device_name, dev_num);
506			if (ret < 0) {
507				ret = -ENOMEM;
508				goto error;
509			}
510		}
511
512		/* Look for this "-devN" trigger */
513		trig_num = find_type_by_name(trigger_name, "trigger");
514		if (trig_num < 0) {
515			/* OK try the simpler "-trigger" suffix instead */
516			free(trigger_name);
517			ret = asprintf(&trigger_name,
518				       "%s-trigger", device_name);
519			if (ret < 0) {
520				ret = -ENOMEM;
521				goto error;
522			}
523		}
524
525		trig_num = find_type_by_name(trigger_name, "trigger");
526		if (trig_num < 0) {
527			fprintf(stderr, "Failed to find the trigger %s\n",
528				trigger_name);
529			ret = trig_num;
530			goto error;
531		}
532
533		printf("iio trigger number being used is %d\n", trig_num);
534	}
535
536	/*
537	 * Parse the files in scan_elements to identify what channels are
538	 * present
539	 */
540	ret = build_channel_array(dev_dir_name, buffer_idx, &channels, &num_channels);
541	if (ret) {
542		fprintf(stderr, "Problem reading scan element information\n"
543			"diag %s\n", dev_dir_name);
544		goto error;
545	}
546	if (num_channels && autochannels == AUTOCHANNELS_ENABLED &&
547	    !force_autochannels) {
548		fprintf(stderr, "Auto-channels selected but some channels "
549			"are already activated in sysfs\n");
550		fprintf(stderr, "Proceeding without activating any channels\n");
551	}
552
553	if ((!num_channels && autochannels == AUTOCHANNELS_ENABLED) ||
554	    (autochannels == AUTOCHANNELS_ENABLED && force_autochannels)) {
555		fprintf(stderr, "Enabling all channels\n");
556
557		ret = enable_disable_all_channels(dev_dir_name, buffer_idx, 1);
558		if (ret) {
559			fprintf(stderr, "Failed to enable all channels\n");
560			goto error;
561		}
562
563		/* This flags that we need to disable the channels again */
564		autochannels = AUTOCHANNELS_ACTIVE;
565
566		ret = build_channel_array(dev_dir_name, buffer_idx, &channels,
567					  &num_channels);
568		if (ret) {
569			fprintf(stderr, "Problem reading scan element "
570				"information\n"
571				"diag %s\n", dev_dir_name);
572			goto error;
573		}
574		if (!num_channels) {
575			fprintf(stderr, "Still no channels after "
576				"auto-enabling, giving up\n");
577			goto error;
578		}
579	}
580
581	if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
582		fprintf(stderr,
583			"No channels are enabled, we have nothing to scan.\n");
584		fprintf(stderr, "Enable channels manually in "
585			FORMAT_SCAN_ELEMENTS_DIR
586			"/*_en or pass -a to autoenable channels and "
587			"try again.\n", dev_dir_name, buffer_idx);
588		ret = -ENOENT;
589		goto error;
590	}
591
592	/*
593	 * Construct the directory name for the associated buffer.
594	 * As we know that the lis3l02dq has only one buffer this may
595	 * be built rather than found.
596	 */
597	ret = asprintf(&buf_dir_name,
598		       "%siio:device%d/buffer%d", iio_dir, dev_num, buffer_idx);
599	if (ret < 0) {
600		ret = -ENOMEM;
601		goto error;
602	}
603
604	if (stat(buf_dir_name, &st)) {
605		fprintf(stderr, "Could not stat() '%s', got error %d: %s\n",
606			buf_dir_name, errno, strerror(errno));
607		ret = -errno;
608		goto error;
609	}
610
611	if (!S_ISDIR(st.st_mode)) {
612		fprintf(stderr, "File '%s' is not a directory\n", buf_dir_name);
613		ret = -EFAULT;
614		goto error;
615	}
616
617	if (!notrigger) {
618		printf("%s %s\n", dev_dir_name, trigger_name);
619		/*
620		 * Set the device trigger to be the data ready trigger found
621		 * above
622		 */
623		ret = write_sysfs_string_and_verify("trigger/current_trigger",
624						    dev_dir_name,
625						    trigger_name);
626		if (ret < 0) {
627			fprintf(stderr,
628				"Failed to write current_trigger file\n");
629			goto error;
630		}
631	}
632
633	ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
634	if (ret < 0) {
635		ret = -ENOMEM;
636		goto error;
637	}
638
639	/* Attempt to open non blocking the access dev */
640	fd = open(buffer_access, O_RDONLY | O_NONBLOCK);
641	if (fd == -1) { /* TODO: If it isn't there make the node */
642		ret = -errno;
643		fprintf(stderr, "Failed to open %s\n", buffer_access);
644		goto error;
645	}
646
647	/* specify for which buffer index we want an FD */
648	buf_fd = buffer_idx;
649
650	ret = ioctl(fd, IIO_BUFFER_GET_FD_IOCTL, &buf_fd);
651	if (ret == -1 || buf_fd == -1) {
652		ret = -errno;
653		if (ret == -ENODEV || ret == -EINVAL)
654			fprintf(stderr,
655				"Device does not have this many buffers\n");
656		else
657			fprintf(stderr, "Failed to retrieve buffer fd\n");
658
659		goto error;
660	}
661
662	/* Setup ring buffer parameters */
663	ret = write_sysfs_int("length", buf_dir_name, buf_len);
664	if (ret < 0)
665		goto error;
666
667	/* Enable the buffer */
668	ret = write_sysfs_int("enable", buf_dir_name, 1);
669	if (ret < 0) {
670		fprintf(stderr,
671			"Failed to enable buffer '%s': %s\n",
672			buf_dir_name, strerror(-ret));
673		goto error;
674	}
675
676	scan_size = size_from_channelarray(channels, num_channels);
677	data = malloc(scan_size * buf_len);
678	if (!data) {
679		ret = -ENOMEM;
680		goto error;
681	}
682
683	/**
684	 * This check is being done here for sanity reasons, however it
685	 * should be omitted under normal operation.
686	 * If this is buffer0, we check that we get EBUSY after this point.
687	 */
688	if (buffer_idx == 0) {
689		errno = 0;
690		read_size = read(fd, data, 1);
691		if (read_size > -1 || errno != EBUSY) {
692			ret = -EFAULT;
693			perror("Reading from '%s' should not be possible after ioctl()");
694			goto error;
695		}
696	}
697
698	/* close now the main chardev FD and let the buffer FD work */
699	if (close(fd) == -1)
700		perror("Failed to close character device file");
701	fd = -1;
 
 
 
702
703	for (j = 0; j < num_loops || num_loops < 0; j++) {
704		if (!noevents) {
705			struct pollfd pfd = {
706				.fd = buf_fd,
707				.events = POLLIN,
708			};
709
710			ret = poll(&pfd, 1, -1);
711			if (ret < 0) {
712				ret = -errno;
713				goto error;
714			} else if (ret == 0) {
715				continue;
716			}
717
718			toread = buf_len;
719		} else {
720			usleep(timedelay);
721			toread = 64;
722		}
723
724		read_size = read(buf_fd, data, toread * scan_size);
725		if (read_size < 0) {
726			if (errno == EAGAIN) {
727				fprintf(stderr, "nothing available\n");
728				continue;
729			} else {
730				break;
731			}
732		}
733		for (i = 0; i < read_size / scan_size; i++)
734			process_scan(data + scan_size * i, channels,
735				     num_channels);
736	}
737
738error:
739	cleanup();
740
741	if (fd >= 0 && close(fd) == -1)
742		perror("Failed to close character device");
743	if (buf_fd >= 0 && close(buf_fd) == -1)
744		perror("Failed to close buffer");
745	free(buffer_access);
746	free(data);
747	free(buf_dir_name);
748	for (i = num_channels - 1; i >= 0; i--) {
749		free(channels[i].name);
750		free(channels[i].generic_name);
751	}
752	free(channels);
753	free(trigger_name);
754	free(device_name);
755	free(dev_dir_name);
756
757	return ret;
758}