timerk.c

frv400开发板上的8253计数器的编程

#include<linux/fs.h>
#include<linux/kernel.h>
#include<linux/module.h>
#include<linux/configfs.h>
#include<linux/init.h>
#include<linux/types.h>
#include<linux/ioctl.h>
#include<asm/io.h>
#include<asm/uaccess.h>

#define	TIMER_IOC_LL		0xdc
#define	TIMER_OPEN		_IOW(TIMER_IOC_LL,0,int)
#define	TIMER			_IOW(TIMER_IOC_LL,1,int)
#define	TIMER_CLOSE		_IOW(TIMER_IOC_LL,2,int)
#define	TIMER_GET		_IOW(TIMER_IOC_LL,4,int)
#define	MAJOR_MINOR	252
#define	DEVICE_NAME		"lltimer"

int	timer_open(struct inode *node,struct file *fop)
{
	outb_p(0x80,0x63);
	return 0;
}

int	timer_close(struct inode *node,struct file *fop)
{
	return 0;
}

static int timer_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	unsigned char data;
	switch(cmd)
	{
		case 	TIMER_OPEN:
			outb_p(0x03,0x61);
			outb_p(0xbe,0x43);
			break;
		case 	TIMER:
			data=arg&0xff;
			outb_p(data,0x42);
			data=(arg>>8)&0xff;
			outb_p(data,0x42);
			break;
		case 	TIMER_CLOSE:
			outb_p(0x00,0x61);
			break;
		case		TIMER_GET:
			outb_p(0x60,arg);
			//inb_p(0x60,arg);
			break;
		default:	
			break;
	}
	return 0;
}

struct file_operations fop=
{		
	open:	timer_open,
	release:	timer_close,
	ioctl:	timer_ioctl,
};

int init_module()
{
	register_chrdev(MAJOR_MINOR,DEVICE_NAME,&fop);
	return 0;
}

void cleanup_module()
{
	unregister_chrdev(MAJOR_MINOR,DEVICE_NAME);
}