git.itanic.dy.fi Git - glucose/blob - hiddev.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <sys/ioctl.h>
   5 #include <linux/hiddev.h>
   6 #include <errno.h>
   7 #include <string.h>
   8 #include <fcntl.h>
   9
  10 #include "hiddev.h"
  11
  12 #define PRINT_FIELD(field) printf(#field ": %04x\n", field)
  13
  14 int hiddev_read(unsigned char *data, int bufsize, int fd)
  15 {
  16         struct hiddev_event readBuffer[READ_BUFFER_LENGTH];
  17         int ret, n, i;
  18
  19         ret = read(fd, readBuffer, sizeof(readBuffer));
  20         if (ret < 0)
  21                 return ret;
  22
  23         n = ret / sizeof(readBuffer[0]);
  24         for (i = 0; i < n && i < bufsize; i++)
  25                 data[i] = readBuffer[i].value;
  26         return n;
  27 }
  28
  29 int hiddev_write(const unsigned char data[64], int fd , int usage_code)
  30 {
  31         int rc = 0, uindex, error;
  32
  33         struct hiddev_usage_ref uref;
  34         struct hiddev_report_info rinfo;
  35
  36         uref.report_id = *data++;
  37         uref.report_type = HID_REPORT_TYPE_OUTPUT;
  38         uref.field_index = 0;
  39
  40         uref.usage_code = usage_code;
  41
  42         for (uindex = 0; uindex < 63; uindex++) {
  43                 uref.usage_index = uindex;
  44                 uref.value = *data++;
  45
  46                 rc = ioctl(fd, HIDIOCSUSAGE, &uref);
  47                 if (rc != 0)
  48                         goto err;
  49         }
  50
  51         rinfo.report_type = HID_REPORT_TYPE_OUTPUT;
  52         rinfo.report_id =  0x0;
  53         rinfo.num_fields = 1;
  54
  55         rc = ioctl(fd, HIDIOCSREPORT, &rinfo);
  56         if (rc != 0)
  57                 goto err2;
  58
  59         return 0;
  60 err2:
  61         printf("HIDIOCSREPORT\n");
  62 err:
  63         error = errno;
  64         printf("Error in IOCTL: %s\n", strerror(error));
  65
  66         return rc;
  67 }
  68
  69 static int get_usagecode(int fd)
  70 {
  71         struct hiddev_usage_ref uref;
  72         int rc, error;
  73
  74         uref.report_type = HID_REPORT_TYPE_OUTPUT;
  75         uref.report_id = 0x0;
  76         uref.field_index = 0;
  77         uref.usage_index = 0;
  78
  79         rc = ioctl(fd, HIDIOCGUCODE, &uref);
  80         if (rc < 0) {
  81                 error = errno;
  82                 printf("Error gettin usage code: %s\n", strerror(error));
  83                 return rc;
  84         }
  85
  86         return uref.usage_code;
  87 }
  88
  89 int hiddev_open(const char *device_path, int *usage_code)
  90 {
  91         struct hiddev_devinfo device_info;
  92         struct hiddev_report_info rinfo;
  93         int ret, error;
  94         int fd;
  95         fd = ret = open(device_path, O_RDWR);
  96
  97         if (fd < 0)
  98                 goto err;
  99
 100
 101         rinfo.report_type = HID_REPORT_TYPE_OUTPUT;
 102         rinfo.report_id = HID_REPORT_ID_FIRST;
 103         ret = ioctl(fd, HIDIOCGREPORTINFO, &rinfo);
 104         if (ret < 0)
 105                 goto err;
 106
 107         PRINT_FIELD(rinfo.report_type);
 108         PRINT_FIELD(rinfo.report_id);
 109         PRINT_FIELD(rinfo.num_fields);
 110
 111         *usage_code = get_usagecode(fd);
 112
 113         if (*usage_code < 0)
 114                 return -8;
 115
 116         ret = ioctl(fd, HIDIOCGDEVINFO, &device_info);
 117
 118         if (ret < 0)
 119                 goto err;
 120
 121         PRINT_FIELD(device_info.bustype);
 122         PRINT_FIELD(device_info.busnum);
 123         PRINT_FIELD(device_info.devnum);
 124         PRINT_FIELD(device_info.ifnum);
 125         PRINT_FIELD(device_info.vendor);
 126         PRINT_FIELD(device_info.product);
 127         PRINT_FIELD(device_info.version);
 128         PRINT_FIELD(device_info.num_applications);
 129
 130         return fd;
 131
 132 err:
 133         error = errno;
 134         printf("Error opening device %s: %s\n", device_path, strerror(error));
 135         return ret;
 136 }
 137