drivers/staging/iio/Documentation/iio_utils.h

   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 #define IIO_EVENT_CODE_RING_50_FULL 200
  11 #define IIO_EVENT_CODE_RING_75_FULL 201
  12 #define IIO_EVENT_CODE_RING_100_FULL 202
  13
  14 struct iio_event_data {
  15         int id;
  16         __s64 timestamp;
  17 };
  18
  19
  20 inline char *find_ring_subelement(const char *directory, const char *subelement)
  21 {
  22         DIR *dp;
  23         const struct dirent *ent;
  24         int pos;
  25         char temp[100];
  26         char *returnstring;
  27         dp = opendir(directory);
  28         if (dp == NULL) {
  29                 printf("could not directory: %s\n", directory);
  30                 return NULL;
  31         }
  32         while (ent = readdir(dp), ent != NULL) {
  33                 if (strcmp(ent->d_name, ".") != 0 &&
  34                     strcmp(ent->d_name, "..") != 0)  {
  35                         if (strncmp(ent->d_name, subelement, strlen(subelement)) == 0) {
  36                                 int length = sprintf(temp, "%s%s%s", directory, ent->d_name, "/");
  37                                 returnstring = malloc(length+1);
  38                                 strncpy(returnstring, temp, length+1);
  39                                 return returnstring;
  40
  41                         }
  42                 }
  43         }
  44         return 0;
  45 }
  46
  47
  48 char *find_type_by_name(const char *name, const char *type)
  49 {
  50         const char *iio_dir = "/sys/class/iio/";
  51         const struct dirent *ent;
  52         int cnt, pos, pos2;
  53
  54         FILE *nameFile;
  55         DIR *dp;
  56         char thisname[100];
  57         char temp[100];
  58
  59         char *returnstring = NULL;
  60         struct stat Stat;
  61         pos = sprintf(temp, "%s", iio_dir);
  62         dp = opendir(iio_dir);
  63         if (dp == NULL) {
  64                 printf("No industrialio devices available");
  65                 return NULL;
  66         }
  67         while (ent = readdir(dp), ent != NULL) {
  68                 cnt++;
  69                 /*reject . and .. */
  70                 if (strcmp(ent->d_name, ".") != 0 &&
  71                     strcmp(ent->d_name, "..") != 0)  {
  72                         /*make sure it isn't a trigger!*/
  73                         if (strncmp(ent->d_name, type, strlen(type)) == 0) {
  74                                 /* build full path to new file */
  75                                 pos2 = pos + sprintf(temp + pos, "%s/", ent->d_name);
  76                                 sprintf(temp + pos2, "name");
  77                                 printf("search location %s\n", temp);
  78                                 nameFile = fopen(temp, "r");
  79                                 if (!nameFile) {
  80                                         sprintf(temp + pos2, "modalias", ent->d_name);
  81                                         nameFile = fopen(temp, "r");
  82                                         if (!nameFile) {
  83                                                 printf("Failed to find a name for device\n");
  84                                                 return NULL;
  85                                         }
  86                                 }
  87                                 fscanf(nameFile, "%s", thisname);
  88                                 if (strcmp(name, thisname) == 0) {
  89                                         returnstring = malloc(strlen(temp) + 1);
  90                                         sprintf(temp + pos2, "");
  91                                         strcpy(returnstring, temp);
  92                                         return returnstring;
  93                                 }
  94                                 fclose(nameFile);
  95
  96                         }
  97                 }
  98         }
  99 }
 100
 101 int write_sysfs_int(char *filename, char *basedir, int val)
 102 {
 103         int ret;
 104         FILE  *sysfsfp;
 105         char temp[100];
 106         sprintf(temp, "%s%s", basedir, filename);
 107         sysfsfp = fopen(temp, "w");
 108         if (sysfsfp == NULL)
 109                 return -1;
 110         fprintf(sysfsfp, "%d", val);
 111         fclose(sysfsfp);
 112         return 0;
 113 }
 114
 115 /**
 116  * write_sysfs_string_and_verify() - string write, readback and verify
 117  * @filename: name of file to write to
 118  * @basedir: the sysfs directory in which the file is to be found
 119  * @val: the string to write
 120  **/
 121 int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
 122 {
 123         int ret;
 124         FILE  *sysfsfp;
 125         char temp[100];
 126         sprintf(temp, "%s%s", basedir, filename);
 127         sysfsfp = fopen(temp, "w");
 128         if (sysfsfp == NULL)
 129                 return -1;
 130         fprintf(sysfsfp, "%s", val);
 131         fclose(sysfsfp);
 132
 133         sysfsfp = fopen(temp, "r");
 134         if (sysfsfp == NULL)
 135                 return -1;
 136         fscanf(sysfsfp, "%s", temp);
 137         if (strcmp(temp, val) != 0) {
 138                 printf("Possible failure in string write %s to %s%s \n",
 139                        val,
 140                        basedir,
 141                        filename);
 142                 return -1;
 143         }
 144         return 0;
 145 }
 146
 147 int read_sysfs_posint(char *filename, char *basedir)
 148 {
 149         int ret;
 150         FILE  *sysfsfp;
 151         char temp[100];
 152         sprintf(temp, "%s%s", basedir, filename);
 153         sysfsfp = fopen(temp, "r");
 154         if (sysfsfp == NULL)
 155                 return -1;
 156         fscanf(sysfsfp, "%d\n", &ret);
 157         fclose(sysfsfp);
 158         return ret;
 159 }