openwrt/package/gpioctl/src/main.c

77 lines
1.7 KiB
C

/*
* 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, MA02111-1307USA
*
* Feedback, Bugs... blogic@openwrt.org
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/gpio_dev.h>
#include <linux/ioctl.h>
void
print_usage()
{
printf("gpioctl dirin|dirout|get|set|clear gpio\n");
exit(0);
}
int
main(int argc, char **argv)
{
int gpio_pin;
int fd;
int result = 0;
if (argc != 3)
{
print_usage();
}
if ((fd = open("/dev/gpio", O_RDWR)) < 0)
{
printf("Error whilst opening /dev/gpio\n");
return -1;
}
gpio_pin = atoi(argv[2]);
printf("using gpio pin %d\n", gpio_pin);
if (!strcmp(argv[1], "dirin"))
{
ioctl(fd, GPIO_DIR_IN, gpio_pin);
} else if (!strcmp(argv[1], "dirout"))
{
ioctl(fd, GPIO_DIR_OUT, gpio_pin);
} else if (!strcmp(argv[1], "get"))
{
result = ioctl(fd, GPIO_GET, gpio_pin);
printf("Pin %d is %s\n", gpio_pin, (result ? "HIGH" : "LOW"));
} else if (!strcmp(argv[1], "set"))
{
ioctl(fd, GPIO_SET, gpio_pin);
} else if (!strcmp(argv[1], "clear"))
{
ioctl(fd, GPIO_CLEAR, gpio_pin);
} else print_usage();
return result;
}