gpio-test.c

嵌入式linux 设备驱动程序

#include <stdio.h>
#include <Stdlib.h> // System
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <linux/delay.h>
#include <sys/ioctl.h>
#define DEVICE_ GPIOTEST “/dev/gpio” //设备节点

int main ( int argc , char * argv [ ] )
{
	int fd ;
	int val=-1;
	fd =open ( DEVICE_GPIOTEST,O_RDONLY ) ; //打开设备
	if ( fd < O )
	{
		perror ( “can not open device” ) ;
		exit ( 1 ) ;
	}
	while ( 1 ) {
		printf ( “please Select number to run program \n” ) ;
		printf ( “1 : led on \n 2 : quit\n” ) ;
		scanf ( “ %d”, & val ) ;
		if ( val ==1 )
			//ioctl ( fd , 1 , 10 ) ;
			write(fd,1,1);
		else if ( val ==2 ) {
			close ( fd ) ;
		}
	}
	return 0;
}