1 /* IIO - useful set of util functionality
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
10 /* Made up value to limit allocation sizes */
11 #include <string.h>
12 #include <stdlib.h>
13 #include <ctype.h>
14 #include <stdio.h>
15 #include <stdint.h>
16 #include <dirent.h>
17
18 #define IIO_MAX_NAME_LENGTH 30
19
20 #define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
21 #define FORMAT_TYPE_FILE "%s_type"
22
23 const char *iio_dir = "/sys/bus/iio/devices/";
24
25 /**
26 * iioutils_break_up_name() - extract generic name from full channel name
27 * @full_name: the full channel name
28 * @generic_name: the output generic channel name
29 **/
iioutils_break_up_name(const char * full_name,char ** generic_name)30 static int iioutils_break_up_name(const char *full_name,
31 char **generic_name)
32 {
33 char *current;
34 char *w, *r;
35 char *working;
36 current = strdup(full_name);
37 working = strtok(current, "_\0");
38 w = working;
39 r = working;
40
41 while (*r != '\0') {
42 if (!isdigit(*r)) {
43 *w = *r;
44 w++;
45 }
46 r++;
47 }
48 *w = '\0';
49 *generic_name = strdup(working);
50 free(current);
51
52 return 0;
53 }
54
55 /**
56 * struct iio_channel_info - information about a given channel
57 * @name: channel name
58 * @generic_name: general name for channel type
59 * @scale: scale factor to be applied for conversion to si units
60 * @offset: offset to be applied for conversion to si units
61 * @index: the channel index in the buffer output
62 * @bytes: number of bytes occupied in buffer output
63 * @mask: a bit mask for the raw output
64 * @is_signed: is the raw value stored signed
65 * @enabled: is this channel enabled
66 **/
67 struct iio_channel_info {
68 char *name;
69 char *generic_name;
70 float scale;
71 float offset;
72 unsigned index;
73 unsigned bytes;
74 unsigned bits_used;
75 unsigned shift;
76 uint64_t mask;
77 unsigned be;
78 unsigned is_signed;
79 unsigned enabled;
80 unsigned location;
81 };
82
83 /**
84 * iioutils_get_type() - find and process _type attribute data
85 * @is_signed: output whether channel is signed
86 * @bytes: output how many bytes the channel storage occupies
87 * @mask: output a bit mask for the raw data
88 * @be: big endian
89 * @device_dir: the iio device directory
90 * @name: the channel name
91 * @generic_name: the channel type name
92 **/
iioutils_get_type(unsigned * is_signed,unsigned * bytes,unsigned * bits_used,unsigned * shift,uint64_t * mask,unsigned * be,const char * device_dir,const char * name,const char * generic_name)93 inline int iioutils_get_type(unsigned *is_signed,
94 unsigned *bytes,
95 unsigned *bits_used,
96 unsigned *shift,
97 uint64_t *mask,
98 unsigned *be,
99 const char *device_dir,
100 const char *name,
101 const char *generic_name)
102 {
103 FILE *sysfsfp;
104 int ret;
105 DIR *dp;
106 char *scan_el_dir, *builtname, *builtname_generic, *filename = 0;
107 char signchar, endianchar;
108 unsigned padint;
109 const struct dirent *ent;
110
111 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
112 if (ret < 0) {
113 ret = -ENOMEM;
114 goto error_ret;
115 }
116 ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
117 if (ret < 0) {
118 ret = -ENOMEM;
119 goto error_free_scan_el_dir;
120 }
121 ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name);
122 if (ret < 0) {
123 ret = -ENOMEM;
124 goto error_free_builtname;
125 }
126
127 dp = opendir(scan_el_dir);
128 if (dp == NULL) {
129 ret = -errno;
130 goto error_free_builtname_generic;
131 }
132 while (ent = readdir(dp), ent != NULL)
133 /*
134 * Do we allow devices to override a generic name with
135 * a specific one?
136 */
137 if ((strcmp(builtname, ent->d_name) == 0) ||
138 (strcmp(builtname_generic, ent->d_name) == 0)) {
139 ret = asprintf(&filename,
140 "%s/%s", scan_el_dir, ent->d_name);
141 if (ret < 0) {
142 ret = -ENOMEM;
143 goto error_closedir;
144 }
145 sysfsfp = fopen(filename, "r");
146 if (sysfsfp == NULL) {
147 printf("failed to open %s\n", filename);
148 ret = -errno;
149 goto error_free_filename;
150 }
151
152 ret = fscanf(sysfsfp,
153 "%ce:%c%u/%u>>%u",
154 &endianchar,
155 &signchar,
156 bits_used,
157 &padint, shift);
158 if (ret < 0) {
159 printf("failed to pass scan type description\n");
160 return ret;
161 }
162 *be = (endianchar == 'b');
163 *bytes = padint / 8;
164 if (*bits_used == 64)
165 *mask = ~0;
166 else
167 *mask = (1 << *bits_used) - 1;
168 if (signchar == 's')
169 *is_signed = 1;
170 else
171 *is_signed = 0;
172 fclose(sysfsfp);
173 free(filename);
174
175 filename = 0;
176 }
177 error_free_filename:
178 if (filename)
179 free(filename);
180 error_closedir:
181 closedir(dp);
182 error_free_builtname_generic:
183 free(builtname_generic);
184 error_free_builtname:
185 free(builtname);
186 error_free_scan_el_dir:
187 free(scan_el_dir);
188 error_ret:
189 return ret;
190 }
191
iioutils_get_param_float(float * output,const char * param_name,const char * device_dir,const char * name,const char * generic_name)192 inline int iioutils_get_param_float(float *output,
193 const char *param_name,
194 const char *device_dir,
195 const char *name,
196 const char *generic_name)
197 {
198 FILE *sysfsfp;
199 int ret;
200 DIR *dp;
201 char *builtname, *builtname_generic;
202 char *filename = NULL;
203 const struct dirent *ent;
204
205 ret = asprintf(&builtname, "%s_%s", name, param_name);
206 if (ret < 0) {
207 ret = -ENOMEM;
208 goto error_ret;
209 }
210 ret = asprintf(&builtname_generic,
211 "%s_%s", generic_name, param_name);
212 if (ret < 0) {
213 ret = -ENOMEM;
214 goto error_free_builtname;
215 }
216 dp = opendir(device_dir);
217 if (dp == NULL) {
218 ret = -errno;
219 goto error_free_builtname_generic;
220 }
221 while (ent = readdir(dp), ent != NULL)
222 if ((strcmp(builtname, ent->d_name) == 0) ||
223 (strcmp(builtname_generic, ent->d_name) == 0)) {
224 ret = asprintf(&filename,
225 "%s/%s", device_dir, ent->d_name);
226 if (ret < 0) {
227 ret = -ENOMEM;
228 goto error_closedir;
229 }
230 sysfsfp = fopen(filename, "r");
231 if (!sysfsfp) {
232 ret = -errno;
233 goto error_free_filename;
234 }
235 fscanf(sysfsfp, "%f", output);
236 break;
237 }
238 error_free_filename:
239 if (filename)
240 free(filename);
241 error_closedir:
242 closedir(dp);
243 error_free_builtname_generic:
244 free(builtname_generic);
245 error_free_builtname:
246 free(builtname);
247 error_ret:
248 return ret;
249 }
250
251 /**
252 * bsort_channel_array_by_index() - reorder so that the array is in index order
253 *
254 **/
255
bsort_channel_array_by_index(struct iio_channel_info ** ci_array,int cnt)256 inline void bsort_channel_array_by_index(struct iio_channel_info **ci_array,
257 int cnt)
258 {
259
260 struct iio_channel_info temp;
261 int x, y;
262
263 for (x = 0; x < cnt; x++)
264 for (y = 0; y < (cnt - 1); y++)
265 if ((*ci_array)[y].index > (*ci_array)[y+1].index) {
266 temp = (*ci_array)[y + 1];
267 (*ci_array)[y + 1] = (*ci_array)[y];
268 (*ci_array)[y] = temp;
269 }
270 }
271
272 /**
273 * build_channel_array() - function to figure out what channels are present
274 * @device_dir: the IIO device directory in sysfs
275 * @
276 **/
build_channel_array(const char * device_dir,struct iio_channel_info ** ci_array,int * counter)277 inline int build_channel_array(const char *device_dir,
278 struct iio_channel_info **ci_array,
279 int *counter)
280 {
281 DIR *dp;
282 FILE *sysfsfp;
283 int count, i;
284 struct iio_channel_info *current;
285 int ret;
286 const struct dirent *ent;
287 char *scan_el_dir;
288 char *filename;
289
290 *counter = 0;
291 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
292 if (ret < 0) {
293 ret = -ENOMEM;
294 goto error_ret;
295 }
296 dp = opendir(scan_el_dir);
297 if (dp == NULL) {
298 ret = -errno;
299 goto error_free_name;
300 }
301 while (ent = readdir(dp), ent != NULL)
302 if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
303 "_en") == 0) {
304 ret = asprintf(&filename,
305 "%s/%s", scan_el_dir, ent->d_name);
306 if (ret < 0) {
307 ret = -ENOMEM;
308 goto error_close_dir;
309 }
310 sysfsfp = fopen(filename, "r");
311 if (sysfsfp == NULL) {
312 ret = -errno;
313 free(filename);
314 goto error_close_dir;
315 }
316 fscanf(sysfsfp, "%u", &ret);
317 printf("%s, %d\n", filename, ret);
318 if (ret == 1)
319 (*counter)++;
320 fclose(sysfsfp);
321 free(filename);
322 }
323 *ci_array = malloc(sizeof(**ci_array) * (*counter));
324 if (*ci_array == NULL) {
325 ret = -ENOMEM;
326 goto error_close_dir;
327 }
328 closedir(dp);
329 dp = opendir(scan_el_dir);
330 //seekdir(dp, 0);
331 count = 0;
332 while (ent = readdir(dp), ent != NULL) {
333 if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
334 "_en") == 0) {
335 current = &(*ci_array)[count++];
336 ret = asprintf(&filename,
337 "%s/%s", scan_el_dir, ent->d_name);
338 if (ret < 0) {
339 ret = -ENOMEM;
340 /* decrement count to avoid freeing name */
341 count--;
342 goto error_cleanup_array;
343 }
344 sysfsfp = fopen(filename, "r");
345 if (sysfsfp == NULL) {
346 free(filename);
347 ret = -errno;
348 goto error_cleanup_array;
349 }
350 fscanf(sysfsfp, "%u", ¤t->enabled);
351 fclose(sysfsfp);
352
353 if (!current->enabled) {
354 free(filename);
355 count--;
356 continue;
357 }
358
359 current->scale = 1.0;
360 current->offset = 0;
361 current->name = strndup(ent->d_name,
362 strlen(ent->d_name) -
363 strlen("_en"));
364 if (current->name == NULL) {
365 free(filename);
366 ret = -ENOMEM;
367 goto error_cleanup_array;
368 }
369 /* Get the generic and specific name elements */
370 ret = iioutils_break_up_name(current->name,
371 ¤t->generic_name);
372 if (ret) {
373 free(filename);
374 goto error_cleanup_array;
375 }
376 ret = asprintf(&filename,
377 "%s/%s_index",
378 scan_el_dir,
379 current->name);
380 if (ret < 0) {
381 free(filename);
382 ret = -ENOMEM;
383 goto error_cleanup_array;
384 }
385 sysfsfp = fopen(filename, "r");
386 fscanf(sysfsfp, "%u", ¤t->index);
387 fclose(sysfsfp);
388 free(filename);
389 /* Find the scale */
390 ret = iioutils_get_param_float(¤t->scale,
391 "scale",
392 device_dir,
393 current->name,
394 current->generic_name);
395 if (ret < 0)
396 goto error_cleanup_array;
397 ret = iioutils_get_param_float(¤t->offset,
398 "offset",
399 device_dir,
400 current->name,
401 current->generic_name);
402 if (ret < 0)
403 goto error_cleanup_array;
404 ret = iioutils_get_type(¤t->is_signed,
405 ¤t->bytes,
406 ¤t->bits_used,
407 ¤t->shift,
408 ¤t->mask,
409 ¤t->be,
410 device_dir,
411 current->name,
412 current->generic_name);
413 }
414 }
415
416 closedir(dp);
417 /* reorder so that the array is in index order */
418 bsort_channel_array_by_index(ci_array, *counter);
419
420 return 0;
421
422 error_cleanup_array:
423 for (i = count - 1; i >= 0; i--)
424 free((*ci_array)[i].name);
425 free(*ci_array);
426 error_close_dir:
427 closedir(dp);
428 error_free_name:
429 free(scan_el_dir);
430 error_ret:
431 return ret;
432 }
433
_write_sysfs_int(char * filename,char * basedir,int val,int verify)434 inline int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
435 {
436 int ret;
437 FILE *sysfsfp;
438 int test;
439 //char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
440 char temp[200];
441 ret = 0;
442 if (temp == NULL)
443 return -ENOMEM;
444 sprintf(temp, "%s/%s", basedir, filename);
445 sysfsfp = fopen(temp, "w");
446 if (sysfsfp == NULL) {
447 printf("failed to open write %s\n", temp);
448 ret = -errno;
449 printf("ERROR1=%d\n", ret);
450 while(1);
451 goto error_free;
452 }
453 fprintf(sysfsfp, "%d", val);
454 fclose(sysfsfp);
455 if (verify) {
456 sysfsfp = fopen(temp, "r");
457 if (sysfsfp == NULL) {
458 printf("failed to open read %s\n", temp);
459 ret = -errno;
460 printf("ERROR2=%d\n", ret);
461 while(1);
462 goto error_free;
463 }
464 fscanf(sysfsfp, "%d", &test);
465 if (test != val) {
466 printf("Possible failure in int write %d to %s%s\n",
467 val,
468 basedir,
469 filename);
470 ret = -1;
471 }
472 }
473 error_free:
474 fclose(sysfsfp);
475 //free(temp);
476 return ret;
477 }
478
write_sysfs_int(char * filename,char * basedir,int val)479 int write_sysfs_int(char *filename, char *basedir, int val)
480 {
481 return _write_sysfs_int(filename, basedir, val, 0);
482 }
483
write_sysfs_int_and_verify(char * filename,char * basedir,int val)484 int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
485 {
486 printf("echo %d > %s/%s\n", val, basedir, filename);
487 return _write_sysfs_int(filename, basedir, val, 1);
488 }
489
write_sysfs_int64(char * filename,char * basedir,long long val)490 inline int write_sysfs_int64(char *filename, char *basedir, long long val)
491 {
492 int ret;
493 FILE *sysfsfp;
494 int test;
495 //char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
496 char temp[200];
497 ret = 0;
498 if (temp == NULL)
499 return -ENOMEM;
500 sprintf(temp, "%s/%s", basedir, filename);
501 sysfsfp = fopen(temp, "w");
502 if (sysfsfp == NULL) {
503 printf("failed to open write %s\n", temp);
504 ret = -errno;
505 printf("ERROR1=%d\n", ret);
506 while(1);
507 goto error_free;
508 }
509 fprintf(sysfsfp, "%lld", val);
510 fclose(sysfsfp);
511 error_free:
512 fclose(sysfsfp);
513 //free(temp);
514 return ret;
515 }
516
_write_sysfs_string(char * filename,char * basedir,char * val,int verify)517 int _write_sysfs_string(char *filename, char *basedir, char *val, int verify)
518 {
519 int ret = 0;
520 FILE *sysfsfp;
521 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
522 if (temp == NULL) {
523 printf("Memory allocation failed\n");
524 return -ENOMEM;
525 }
526 sprintf(temp, "%s/%s", basedir, filename);
527 sysfsfp = fopen(temp, "w");
528 if (sysfsfp == NULL) {
529 printf("Could not open %s\n", temp);
530 ret = -errno;
531 goto error_free;
532 }
533 fprintf(sysfsfp, "%s", val);
534 fclose(sysfsfp);
535 if (verify) {
536 sysfsfp = fopen(temp, "r");
537 if (sysfsfp == NULL) {
538 printf("could not open file to verify\n");
539 ret = -errno;
540 goto error_free;
541 }
542 fscanf(sysfsfp, "%s", temp);
543 if (strcmp(temp, val) != 0) {
544 printf("Possible failure in string write of %s "
545 "Should be %s "
546 "written to %s\%s\n",
547 temp,
548 val,
549 basedir,
550 filename);
551 ret = -1;
552 }
553 }
554 error_free:
555 free(temp);
556
557 return ret;
558 }
559
560 /**
561 * write_sysfs_string_and_verify() - string write, readback and verify
562 * @filename: name of file to write to
563 * @basedir: the sysfs directory in which the file is to be found
564 * @val: the string to write
565 **/
write_sysfs_string_and_verify(char * filename,char * basedir,char * val)566 int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
567 {
568 return _write_sysfs_string(filename, basedir, val, 1);
569 }
570
write_sysfs_string(char * filename,char * basedir,char * val)571 int write_sysfs_string(char *filename, char *basedir, char *val)
572 {
573 return _write_sysfs_string(filename, basedir, val, 0);
574 }
575
read_sysfs_posint(char * filename,char * basedir)576 int read_sysfs_posint(char *filename, char *basedir)
577 {
578 int ret;
579 FILE *sysfsfp;
580 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
581 if (temp == NULL) {
582 printf("Memory allocation failed");
583 return -ENOMEM;
584 }
585 sprintf(temp, "%s/%s", basedir, filename);
586 sysfsfp = fopen(temp, "r");
587 if (sysfsfp == NULL) {
588 ret = -errno;
589 goto error_free;
590 }
591 fscanf(sysfsfp, "%d\n", &ret);
592 fclose(sysfsfp);
593 error_free:
594 free(temp);
595 return ret;
596 }
597
read_sysfs_poslonglong(char * filename,char * basedir)598 long long read_sysfs_poslonglong(char *filename, char *basedir)
599 {
600 long long ret;
601 FILE *sysfsfp;
602 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
603 if (temp == NULL) {
604 printf("Memory allocation failed");
605 return -ENOMEM;
606 }
607 sprintf(temp, "%s/%s", basedir, filename);
608 sysfsfp = fopen(temp, "r");
609 if (sysfsfp == NULL) {
610 ret = -errno;
611 goto error_free;
612 }
613 fscanf(sysfsfp, "%lld\n", &ret);
614 fclose(sysfsfp);
615 error_free:
616 free(temp);
617 return ret;
618 }
619
read_sysfs_float(char * filename,char * basedir,float * val)620 int read_sysfs_float(char *filename, char *basedir, float *val)
621 {
622 float ret = 0;
623 FILE *sysfsfp;
624 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
625 if (temp == NULL) {
626 printf("Memory allocation failed");
627 return -ENOMEM;
628 }
629 sprintf(temp, "%s/%s", basedir, filename);
630 sysfsfp = fopen(temp, "r");
631 if (sysfsfp == NULL) {
632 ret = -errno;
633 goto error_free;
634 }
635 fscanf(sysfsfp, "%f\n", val);
636 fclose(sysfsfp);
637 error_free:
638 free(temp);
639 return ret;
640 }
enable(const char * device_dir,struct iio_channel_info ** ci_array,int * counter)641 int enable(const char *device_dir,
642 struct iio_channel_info **ci_array,
643 int *counter)
644 {
645 DIR *dp;
646 int ret;
647 const struct dirent *ent;
648 char *scan_el_dir;
649
650 *counter = 0;
651 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
652 if (ret < 0) {
653 ret = -ENOMEM;
654 goto error_ret;
655 }
656 dp = opendir(scan_el_dir);
657 if (dp == NULL) {
658 ret = -errno;
659 goto error_free_name;
660 }
661 while (ent = readdir(dp), ent != NULL)
662 if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
663 "_en") == 0) {
664 write_sysfs_int_and_verify((char *)ent->d_name, scan_el_dir, 1);
665 }
666 return 0;
667 error_ret:
668 error_free_name:
669 return -1;
670 }
disable_q_out(const char * device_dir,struct iio_channel_info ** ci_array,int * counter)671 int disable_q_out(const char *device_dir,
672 struct iio_channel_info **ci_array,
673 int *counter) {
674 DIR *dp;
675 int ret;
676 const struct dirent *ent;
677 char *scan_el_dir;
678
679 *counter = 0;
680 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
681 if (ret < 0) {
682 ret = -ENOMEM;
683 goto error_ret;
684 }
685 dp = opendir(scan_el_dir);
686 if (dp == NULL) {
687 ret = -errno;
688 goto error_free_name;
689 }
690 while (ent = readdir(dp), ent != NULL)
691 if (strncmp(ent->d_name, "in_quaternion", strlen("in_quaternion")) == 0) {
692 write_sysfs_int_and_verify((char *)ent->d_name, scan_el_dir, 0);
693 }
694 return 0;
695 error_ret:
696 error_free_name:
697 return -1;
698
699 }
700
701