s3c44b0-key.c

４４b0和linux操作系统下的按键中断驱动程序

#include	<linux/config.h>
#include	<linux/module.h>
#include	<linux/kernel.h>
#include	<linux/init.h>
#include	<asm/delay.h>
#include	<asm/uaccess.h>
#include	<linux/fs.h>
#include	<linux/devfs_fs_kernel.h>
#include	<linux/sched.h>
#include	<asm/hardware.h>

//#undef	DEBUG
#define		DEBUG
#ifdef		DEBUG
#define		DPRINTK(x... )	printk("s3c44b0_key:"##x)
#else	
#define		DPRINTK(x...)
#endif
#define 	DEVICE_NAME	"s3c44b0-key"
#define		KEYMinor	1

static 	int	KEYMajor = 0;
static 	int	s3c44b0_KEY_read(struct file *filp, char *buf, size_t count,loff_t *f_pos)
{
	return 0;
}

static	int	s3c44b0_KEY_open(struct inode *inode,struct file *filp)
{
	MOD_INC_USE_COUNT;
	DPRINTK("open\n");
	return 0;
}

static	int	s3c44b0_KEY_release(struct inode *inode, struct file *filp)
{
	MOD_DEC_USE_COUNT;
	DPRINTK("release\n");
	return 0;
}

static	struct	file_operations s3c44b0_fops = {
	owner:	THIS_MODULE,
	open:	s3c44b0_KEY_open,
	write:  s3c44b0_KEY_read,
	release:s3c44b0_KEY_release,
};

static	void	s3c44b0x_KEY_isr(int irq,void *dev_id,struct pt_regs *regs)
{
	switch(irq)
	{
		case 24:
			printk("A\n");
			break;
		case 25:
			printk("B\n");
			break;
	} 
	*((volatile unsigned int*)S3C44B0X_I_ISPC)=(0x1<<irq);
}

#ifdef CONFIG_DEVFS_FS
static	devfs_handle_t	devfs_s3c44b0_dir,devfs_s3c44b0raw;
#endif

static	int	__init	s3c44b0_KEY_init(void)
{
	int ret;	
	ret = register_chrdev(KEYMajor,DEVICE_NAME,&s3c44b0_fops);
	if(ret<0)
	{
		printk(DEVICE_NAME "can't get major number\n");
		return ret;
	}
	KEYMajor = ret;
#ifdef	CONFIG_DEVFS_FS
        devfs_s3c44b0_dir=devfs_mk_dir(NULL,"key",NULL);
	devfs_s3c44b0raw=devfs_register(devfs_s3c44b0_dir,"0",DEVFS_FL_DEFAULT,KEYMajor,\
					KEYMinor,S_IFCHR|S_IRUSR|S_IWUSR,&s3c44b0_fops,NULL);
#endif
	if(request_irq(24,s3c44b0x_KEY_isr,SA_INTERRUPT,DEVICE_NAME,NULL)<0)
	DPRINTK("Failed to register IRQ 24\n");
	if(request_irq(25,s3c44b0x_KEY_isr,SA_INTERRUPT,DEVICE_NAME,NULL)<0)
	DPRINTK("Failed to register IRQ 25\n");
	
	printk(DEVICE_NAME "initialized IRQ 24 25\n");
	return 0;
}

static	void	__exit	s3c44b0_KEY_exit(void)
{
	free_irq(24,NULL);
	free_irq(25,NULL);
#ifdef	CONFIG_DEVFS_FS
	devfs_unregister(devfs_s3c44b0raw);
	devfs_unregister(devfs_s3c44b0_dir);
#endif
	unregister_chrdev(KEYMajor, DEVICE_NAME);
	
}

module_init(s3c44b0_KEY_init);
module_exit(s3c44b0_KEY_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("ZCY");
MODULE_DESCRIPTION("SEG7 driver fo EB44b0");