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#include<linux/module.h>
#include<linux/kernel.h>
#include<linux/fs.h>
#include<linux/init.h>
#include<linux/delay.h>
#include<asm/irq.h>
#include<linux/interrupt.h>
#include<asm/uaccess.h>
#include<asm/arch/regs-gpio.h>
#include<asm/hardware.h>
#define DEVICE_NAME "buttons"
#define BUTTON_MAJOR 232
static volatile int press_cnt[]={0,0,0,0};
struct button_irq_desc
{
int irq;
unsigned long flags;
char *name;
};
static struct button_irq_desc button_irqs[]=
{
{IRQ_EINT1,IRQF_TRIGGER_FALLING,"KEY1"},
{IRQ_EINT2,IRQF_TRIGGER_FALLING,"KEY2"},
{IRQ_EINT3, IRQF_TRIGGER_FALLING,"KEY3"},
// {IRQ_EINT0, IRQF_TRIGGER_FALLING,"KEY4"},
};
static irqreturn_t buttons_interrupt(int irq,void *dev_id)
{
volatile int *press_cnt=(volatile int *)dev_id;
*press_cnt=*press_cnt+1;
// ev_press=1; //表示中断发生了
// wake_up_interruptible(&button_waitq); //唤醒休眠的进程
printk("Now Key interrupt occur %d times!!!\n",*press_cnt);
return IRQ_RETVAL(IRQ_HANDLED);
}
static int s3c24xx_buttons_open(struct inode *inode,struct file *file)
{
int i;
int err;
for(i=0;i<sizeof(button_irqs)/sizeof(button_irqs[0]);i++)
{
//注册中断处理函数
err=request_irq(button_irqs[i].irq,buttons_interrupt,button_irqs[i].flags,button_irqs[i].name,(void *)&press_cnt[i]);
if(err)break;
}
if(err)
{
//释放已经注册的中断
i--;
for(;i>=0;i--)
free_irq(button_irqs[i].irq,(void *)&press_cnt[i]);
return -EBUSY;
}
return 0;
}
static int s3c24xx_buttons_close(struct inode *inode,struct file *file)
{
int i;
for(i=0;i<sizeof(button_irqs)/sizeof(button_irqs[0]);i++)
{
free_irq(button_irqs[i].irq,(void *)&press_cnt[i]);
}
return 0;
}
static struct file_operations s3c24xx_buttons_fops=
{
.owner = THIS_MODULE,
.open = s3c24xx_buttons_open,
.release = s3c24xx_buttons_close,
// .read = s3c24xx_buttons_read,
};
static int __init s3c24xx_buttons_init(void)
{
int ret;
ret =register_chrdev(BUTTON_MAJOR,DEVICE_NAME,&s3c24xx_buttons_fops);
if(ret<0)
{
printk(DEVICE_NAME "can't register major number\n");
return ret;
}
printk(DEVICE_NAME "initialized \n");
return 0;
}
static void __exit s3c24xx_buttons_exit(void)
{
unregister_chrdev(BUTTON_MAJOR,DEVICE_NAME);
}
module_init(s3c24xx_buttons_init);
module_exit(s3c24xx_buttons_exit); |
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