1 /* IIO - useful set of util functionality
3 * Copyright (c) 2008 Jonathan Cameron
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.
19 #include "iio_utils.h"
21 const char *iio_dir = "/sys/bus/iio/devices/";
23 static char * const iio_direction[] = {
29 * iioutils_break_up_name() - extract generic name from full channel name
30 * @full_name: the full channel name
31 * @generic_name: the output generic channel name
33 int iioutils_break_up_name(const char *full_name,
38 char *working, *prefix = "";
41 for (i = 0; i < sizeof(iio_direction) / sizeof(iio_direction[0]); i++)
42 if (!strncmp(full_name, iio_direction[i],
43 strlen(iio_direction[i]))) {
44 prefix = iio_direction[i];
48 current = strdup(full_name + strlen(prefix) + 1);
49 working = strtok(current, "_\0");
62 asprintf(generic_name, "%s_%s", prefix, working);
69 * iioutils_get_type() - find and process _type attribute data
70 * @is_signed: output whether channel is signed
71 * @bytes: output how many bytes the channel storage occupies
72 * @mask: output a bit mask for the raw data
74 * @device_dir: the iio device directory
75 * @name: the channel name
76 * @generic_name: the channel type name
78 int iioutils_get_type(unsigned *is_signed,
84 const char *device_dir,
86 const char *generic_name)
91 char *scan_el_dir, *builtname, *builtname_generic, *filename = 0;
92 char signchar, endianchar;
94 const struct dirent *ent;
96 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
101 ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
104 goto error_free_scan_el_dir;
106 ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name);
109 goto error_free_builtname;
112 dp = opendir(scan_el_dir);
115 goto error_free_builtname_generic;
117 while (ent = readdir(dp), ent != NULL)
119 * Do we allow devices to override a generic name with
122 if ((strcmp(builtname, ent->d_name) == 0) ||
123 (strcmp(builtname_generic, ent->d_name) == 0)) {
124 ret = asprintf(&filename,
125 "%s/%s", scan_el_dir, ent->d_name);
130 sysfsfp = fopen(filename, "r");
131 if (sysfsfp == NULL) {
132 printf("failed to open %s\n", filename);
134 goto error_free_filename;
137 ret = fscanf(sysfsfp,
144 printf("failed to pass scan type description\n");
146 goto error_close_sysfsfp;
148 *be = (endianchar == 'b');
150 if (*bits_used == 64)
153 *mask = (1 << *bits_used) - 1;
172 error_free_builtname_generic:
173 free(builtname_generic);
174 error_free_builtname:
176 error_free_scan_el_dir:
182 int iioutils_get_param_float(float *output,
183 const char *param_name,
184 const char *device_dir,
186 const char *generic_name)
191 char *builtname, *builtname_generic;
192 char *filename = NULL;
193 const struct dirent *ent;
195 ret = asprintf(&builtname, "%s_%s", name, param_name);
200 ret = asprintf(&builtname_generic,
201 "%s_%s", generic_name, param_name);
204 goto error_free_builtname;
206 dp = opendir(device_dir);
209 goto error_free_builtname_generic;
211 while (ent = readdir(dp), ent != NULL)
212 if ((strcmp(builtname, ent->d_name) == 0) ||
213 (strcmp(builtname_generic, ent->d_name) == 0)) {
214 ret = asprintf(&filename,
215 "%s/%s", device_dir, ent->d_name);
220 sysfsfp = fopen(filename, "r");
223 goto error_free_filename;
225 fscanf(sysfsfp, "%f", output);
233 error_free_builtname_generic:
234 free(builtname_generic);
235 error_free_builtname:
242 * bsort_channel_array_by_index() - reorder so that the array is in index order
246 void bsort_channel_array_by_index(struct iio_channel_info **ci_array,
250 struct iio_channel_info temp;
253 for (x = 0; x < cnt; x++)
254 for (y = 0; y < (cnt - 1); y++)
255 if ((*ci_array)[y].index > (*ci_array)[y+1].index) {
256 temp = (*ci_array)[y + 1];
257 (*ci_array)[y + 1] = (*ci_array)[y];
258 (*ci_array)[y] = temp;
263 * build_channel_array() - function to figure out what channels are present
264 * @device_dir: the IIO device directory in sysfs
267 int build_channel_array(const char *device_dir,
268 struct iio_channel_info **ci_array,
274 struct iio_channel_info *current;
276 const struct dirent *ent;
281 ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
286 dp = opendir(scan_el_dir);
289 goto error_free_name;
291 while (ent = readdir(dp), ent != NULL)
292 if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
294 ret = asprintf(&filename,
295 "%s/%s", scan_el_dir, ent->d_name);
298 goto error_close_dir;
300 sysfsfp = fopen(filename, "r");
301 if (sysfsfp == NULL) {
304 goto error_close_dir;
306 fscanf(sysfsfp, "%i", &ret);
312 *ci_array = malloc(sizeof(**ci_array) * (*counter));
313 if (*ci_array == NULL) {
315 goto error_close_dir;
319 while (ent = readdir(dp), ent != NULL) {
320 if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
322 int current_enabled = 0;
324 current = &(*ci_array)[count++];
325 ret = asprintf(&filename,
326 "%s/%s", scan_el_dir, ent->d_name);
329 /* decrement count to avoid freeing name */
331 goto error_cleanup_array;
333 sysfsfp = fopen(filename, "r");
334 if (sysfsfp == NULL) {
337 goto error_cleanup_array;
339 fscanf(sysfsfp, "%i", ¤t_enabled);
342 if (!current_enabled) {
348 current->scale = 1.0;
350 current->name = strndup(ent->d_name,
351 strlen(ent->d_name) -
353 if (current->name == NULL) {
356 goto error_cleanup_array;
358 /* Get the generic and specific name elements */
359 ret = iioutils_break_up_name(current->name,
360 ¤t->generic_name);
363 goto error_cleanup_array;
365 ret = asprintf(&filename,
372 goto error_cleanup_array;
374 sysfsfp = fopen(filename, "r");
375 fscanf(sysfsfp, "%u", ¤t->index);
379 ret = iioutils_get_param_float(¤t->scale,
383 current->generic_name);
385 goto error_cleanup_array;
386 ret = iioutils_get_param_float(¤t->offset,
390 current->generic_name);
392 goto error_cleanup_array;
393 ret = iioutils_get_type(¤t->is_signed,
401 current->generic_name);
406 /* reorder so that the array is in index order */
407 bsort_channel_array_by_index(ci_array, *counter);
412 for (i = count - 1; i >= 0; i--)
413 free((*ci_array)[i].name);
424 * find_type_by_name() - function to match top level types by name
425 * @name: top level type instance name
426 * @type: the type of top level instance being sort
428 * Typical types this is used for are device and trigger.
430 int find_type_by_name(const char *name, const char *type)
432 const struct dirent *ent;
433 int number, numstrlen;
437 char thisname[IIO_MAX_NAME_LENGTH];
440 dp = opendir(iio_dir);
442 printf("No industrialio devices available\n");
446 while (ent = readdir(dp), ent != NULL) {
447 if (strcmp(ent->d_name, ".") != 0 &&
448 strcmp(ent->d_name, "..") != 0 &&
449 strlen(ent->d_name) > strlen(type) &&
450 strncmp(ent->d_name, type, strlen(type)) == 0) {
451 numstrlen = sscanf(ent->d_name + strlen(type),
454 /* verify the next character is not a colon */
455 if (strncmp(ent->d_name + strlen(type) + numstrlen,
458 filename = malloc(strlen(iio_dir)
462 if (filename == NULL) {
466 sprintf(filename, "%s%s%d/name",
470 nameFile = fopen(filename, "r");
476 fscanf(nameFile, "%s", thisname);
478 if (strcmp(name, thisname) == 0) {
489 int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
494 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
498 sprintf(temp, "%s/%s", basedir, filename);
499 sysfsfp = fopen(temp, "w");
500 if (sysfsfp == NULL) {
501 printf("failed to open %s\n", temp);
505 fprintf(sysfsfp, "%d", val);
508 sysfsfp = fopen(temp, "r");
509 if (sysfsfp == NULL) {
510 printf("failed to open %s\n", temp);
514 fscanf(sysfsfp, "%d", &test);
517 printf("Possible failure in int write %d to %s%s\n",
529 int write_sysfs_int(char *filename, char *basedir, int val)
531 return _write_sysfs_int(filename, basedir, val, 0);
534 int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
536 return _write_sysfs_int(filename, basedir, val, 1);
539 int _write_sysfs_string(char *filename, char *basedir, char *val, int verify)
543 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
546 printf("Memory allocation failed\n");
549 sprintf(temp, "%s/%s", basedir, filename);
550 sysfsfp = fopen(temp, "w");
551 if (sysfsfp == NULL) {
552 printf("Could not open %s\n", temp);
556 fprintf(sysfsfp, "%s", val);
559 sysfsfp = fopen(temp, "r");
560 if (sysfsfp == NULL) {
561 printf("could not open file to verify\n");
565 fscanf(sysfsfp, "%s", temp);
567 if (strcmp(temp, val) != 0) {
568 printf("Possible failure in string write of %s "
570 "written to %s\%s\n",
585 * write_sysfs_string_and_verify() - string write, readback and verify
586 * @filename: name of file to write to
587 * @basedir: the sysfs directory in which the file is to be found
588 * @val: the string to write
590 int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
592 return _write_sysfs_string(filename, basedir, val, 1);
595 int write_sysfs_string(char *filename, char *basedir, char *val)
597 return _write_sysfs_string(filename, basedir, val, 0);
600 int read_sysfs_posint(char *filename, char *basedir)
604 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
607 printf("Memory allocation failed");
610 sprintf(temp, "%s/%s", basedir, filename);
611 sysfsfp = fopen(temp, "r");
612 if (sysfsfp == NULL) {
616 fscanf(sysfsfp, "%d\n", &ret);
623 int read_sysfs_float(char *filename, char *basedir, float *val)
627 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
630 printf("Memory allocation failed");
633 sprintf(temp, "%s/%s", basedir, filename);
634 sysfsfp = fopen(temp, "r");
635 if (sysfsfp == NULL) {
639 fscanf(sysfsfp, "%f\n", val);
646 int read_sysfs_string(const char *filename, const char *basedir, char *str)
650 char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
653 printf("Memory allocation failed");
656 sprintf(temp, "%s/%s", basedir, filename);
657 sysfsfp = fopen(temp, "r");
658 if (sysfsfp == NULL) {
662 fscanf(sysfsfp, "%s\n", str);
669 #endif /* _IIO_UTILS_H */