HIDDEV examples
 | These complete examples will compile with gcc -Wall -W. If you have updated your linux kernel, and have not updated your header files, you may need to use the -I option to pick up the version of hiddev.h from your new kernel. For example, if you have the kernel in a directory /a/b/c, then you would compile the first example with the command gcc -Wall -W -I/a/b/c/include example1.c -o example1. Naturally, you replace /a/b/c with the directory you really used. |
Example 1. HIDIOCVERSION example
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <asm/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/hiddev.h>
int main (int argc, char **argv) {
int fd = -1;
int version;
/* ioctl() requires a file descriptor, so we check we got one, and then open it */
if (argc != 2) {
fprintf(stderr, "usage: %s hiddevice - probably /dev/usb/hiddev0\n", argv[0]);
exit(1);
}
if ((fd = open(argv[1], O_RDONLY)) < 0) {
perror("hiddev open");
exit(1);
}
/* ioctl() accesses the underlying driver */
ioctl(fd, HIDIOCGVERSION, &version);
/* the HIDIOCGVERSION ioctl() returns an int */
/* so we unpack it and display it */
printf("hiddev driver version is %d.%d.%d\n",
version >> 16, (version >> 8) & 0xff, version & 0xff);
close(fd);
exit(0);
} |
Example 2. HIDIOCGDEVINFO example
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <asm/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/hiddev.h>
int main (int argc, char **argv) {
int fd = -1;
struct hiddev_devinfo device_info;
/* ioctl() requires a file descriptor, so we check we got one, and then open it */
if (argc != 2) {
fprintf(stderr, "usage: %s hiddevice - probably /dev/usb/hiddev0\n", argv[0]);
exit(1);
}
if ((fd = open(argv[1], O_RDONLY)) < 0) {
perror("hiddev open");
exit(1);
}
/* suck out some device information */
ioctl(fd, HIDIOCGDEVINFO, &device_info);
/* the HIDIOCGDEVINFO ioctl() returns hiddev_devinfo
* structure - see <linux/hiddev.h>
* So we work through the various elements, displaying
* each of them
*/
printf("vendor 0x%04hx product 0x%04hx version 0x%04hx ",
device_info.vendor, device_info.product, device_info.version);
printf("has %i application%s ", device_info.num_applications,
(device_info.num_applications==1?"":"s"));
printf("and is on bus: %d devnum: %d ifnum: %d\n",
device_info.busnum, device_info.devnum, device_info.ifnum);
close(fd);
exit(0);
} |
Example 3. HIDIOCAPPLICATION example
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <asm/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/hiddev.h>
int main (int argc, char **argv) {
int fd = -1;
unsigned int yalv;
int appl;
struct hiddev_devinfo device_info;
/* ioctl() requires a file descriptor, so we check we got one, and then open it */
if (argc != 2) {
fprintf(stderr, "usage: %s hiddevice - probably /dev/usb/hiddev0\n", argv[0]);
exit(1);
}
if ((fd = open(argv[1], O_RDONLY)) < 0) {
perror("hiddev open");
exit(1);
}
/* suck out some device information */
ioctl(fd, HIDIOCGDEVINFO, &device_info);
/* Now that we have the number of applications (in the
* device_info.num_applications field),
* we can retrieve them using the HIDIOCAPPLICATION ioctl()
* applications are indexed from 0..{num_applications-1}
*/
for (yalv = 0; yalv < device_info.num_applications; yalv++) {
appl = ioctl(fd, HIDIOCAPPLICATION, yalv);
if (appl > 0) {
printf("Application %i is 0x%x ", yalv, appl);
/* The magic values come from various usage table specs */
switch ( appl >> 16)
{
case 0x01 :
printf("(Generic Desktop Page)\n");
break;
case 0x0c :
printf("(Consumer Product Page)\n");
break;
case 0x80 :
printf("(USB Monitor Page)\n");
break;
case 0x81 :
printf("(USB Enumerated Values Page)\n");
break;
case 0x82 :
printf("(VESA Virtual Controls Page)\n");
break;
case 0x83 :
printf("(Reserved Monitor Page)\n");
break;
case 0x84 :
printf("(Power Device Page)\n");
break;
case 0x85 :
printf("(Battery System Page)\n");
break;
case 0x86 :
case 0x87 :
printf("(Reserved Power Device Page)\n");
break;
default :
printf("(Unknown page - needs to be added)\n");
}
}
}
close(fd);
exit(0);
} |