驱动程序如下
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/module.h>#include <linux/kernel.h>#include <linux/fs.h>#include <linux/init.h>#include <linux/delay.h>#include <linux/irq.h>#include <asm/uaccess.h>#include <asm/irq.h>#include <asm/io.h>#include <mach/gpio.h>#include<linux/cdev.h> int key_id;struct cdev cdev;dev_t devno;/*等待队列头*/wait_queue_head_t key_q;/*中断事件标志，中断服务程序将它置为1，read函数将它置为0*/unsigned int key_num=0;#define DRIVER_NAME "my_key_driver"struct class *my_class;static irqreturn_t key_func(int irq,void *dev_id){key_id=(int)dev_id;/*唤醒*/key_num=1;wake_up(&key_q);return 0;}static int key_open(struct inode *inode,struct file *file){request_irq(IRQ_EINT(16),key_func,IRQF_TRIGGER_FALLING,"k1",1);request_irq(IRQ_EINT(17),key_func,IRQF_TRIGGER_FALLING,"k2",2);request_irq(IRQ_EINT(18),key_func,IRQF_TRIGGER_FALLING,"k3",3);request_irq(IRQ_EINT(19),key_func,IRQF_TRIGGER_FALLING,"k4",4);request_irq(IRQ_EINT(24),key_func,IRQF_TRIGGER_FALLING,"k5",5);request_irq(IRQ_EINT(25),key_func,IRQF_TRIGGER_FALLING,"k6",6);request_irq(IRQ_EINT(26),key_func,IRQF_TRIGGER_FALLING,"k7",7);request_irq(IRQ_EINT(27),key_func,IRQF_TRIGGER_FALLING,"k8",8);return 0;}static int key_close(struct inode *inode,struct file *file){free_irq(IRQ_EINT(16),1);free_irq(IRQ_EINT(17),2);free_irq(IRQ_EINT(18),3);free_irq(IRQ_EINT(19),4);free_irq(IRQ_EINT(24),5);free_irq(IRQ_EINT(25),6);free_irq(IRQ_EINT(26),7);free_irq(IRQ_EINT(27),8);return 0;}ssize_t key_read(struct file *filp, char __user *buf, size_t size,loff_t *pos){/*如果没有按键按下，休眠，让出CPU*/wait_event(key_q,key_num);/*如果有按键按下*/copy_to_user(buf,&key_id,sizeof(key_id)); key_num=0;return 0;}static struct file_Operations key_fops ={.owner = THIS_MODULE,.open = key_open,.release = key_close,.read=key_read,};static int __init key_interrupt_init(void){cdev_init(&cdev,&key_fops);alloc_chrdev_region(&devno, 0 , 1 , "mykey_interrupt");cdev_add(&cdev, devno, 1);my_class = class_create(THIS_MODULE, "key_interrupt_class");if(IS_ERR(my_class)){PRintk("Err: failed in creating class./n");return -1;}device_create(my_class, NULL, devno,NULL,"key_interrput_driver");init_waitqueue_head(&key_q);return 0;}static void key_interrupt_exit(void){device_destroy(my_class,devno);class_destroy(my_class);cdev_del(&cdev);unregister_chrdev_region(devno,1);}module_init(key_interrupt_init);module_exit(key_interrupt_exit);MODULE_LICENSE("GPL");MODULE_AUTHOR("EIGHT_FIVE");
测试程序如下
#include<stdio.h>#include<sys/ioctl.h>#include<sys/types.h>#include<sys/stat.h>#include<fcntl.h>int main(int argv,char **argc){int fd,buf;fd=open("/dev/key_interrput_driver",0x666);while(1){read(fd,&buf,4);printf("key_val =%d/n",buf);}return 0;}
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