keys4.c

华恒开发板s3c2410的按钮中断处理程序.其中keys4.c 为驱动程序,key.c为按钮测试程序. 先用insmod加载模块.再运行./key进行测试

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>

#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <asm/irq.h>
#include <asm/hardware.h>
#include <asm/uaccess.h>
#include <asm/arch/irqs.h>
#include <asm/io.h>
#include <asm/semaphore.h> 
#include <linux/major.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>

#define KEYS4_MAJOR 138 

#define NOKEY	0
#define KEY1	'1'
#define KEY2	'2'
#define KEY3	'3'
#define KEY4	'4'


static struct semaphore key_sem;
static char key = NOKEY;

devfs_handle_t devfs_keys4;


static void  keys4_clearirq(void)
{
/*respond to EINT2-EINT5*/
	SRCPND &= (~0x0000001c);  //bit2,3,4
	INTPND = INTPND;
	EINTPEND &= (~0x0000003c); //bit2,3,4,5
}

static void key1_irq_isr(int irq, void *dev_id, struct pt_regs *regs)
{
	keys4_clearirq();
//	SRCPND &= (~0x0000001c);  //bit2,3,4
//	INTPND = INTPND;
//	EINTPEND &= (~0x0000003c); //bit2,3,4,5
	key=KEY1;
	up(&key_sem);
}
static void key2_irq_isr(int irq, void *dev_id, struct pt_regs *regs)
{
	keys4_clearirq();
//	SRCPND &= (~0x0000001c);  //bit2,3,4
//	INTPND = INTPND;
//	EINTPEND &= (~0x0000003c); //bit2,3,4,5
        key=KEY2;
	up(&key_sem);
}

static void key3_irq_isr(int irq, void *dev_id, struct pt_regs *regs)
{
	keys4_clearirq();
//	SRCPND &= (~0x0000001c);  //bit2,3,4
//	INTPND = INTPND;
//	EINTPEND &= (~0x0000003c); //bit2,3,4,5
        key=KEY3;
	up(&key_sem);
}
static void key4_irq_isr(int irq, void *dev_id, struct pt_regs *regs)
{
	keys4_clearirq();
//	SRCPND &= (~0x0000001c);  //bit2,3,4
//	INTPND = INTPND;
//	EINTPEND &= (~0x0000003c); //bit2,3,4,5
	key=KEY4;
	up(&key_sem);
}

static ssize_t keys4_read(struct inode *inode, char *buf, unsigned long count)
{
	down_interruptible(&key_sem);
	put_user(key,buf);
	key=NOKEY;
	return 1;
}

int keys4_open(struct inode *inode, struct file *file)
{

//	keys4_clearirq();
//	enable_irq(IRQ_EINT2);
//	enable_irq(IRQ_EINT3);
//	enable_irq(IRQ_EINT4);
//	enable_irq(IRQ_EINT5);
	
	sema_init(&key_sem,0);
	return 0;
}

void keys4_release(struct inode *inode, struct file *filp)
{
//	keys4_cleanirq();
//        disable_irq(IRQ_EINT2);
//	disable_irq(IRQ_EINT3);
//	disable_irq(IRQ_EINT4);
//	disable_irq(IRQ_EINT5);
        printk("release ok!\n");
        return;
}


struct file_operations keys4_fops = {
	read:keys4_read,
	open:keys4_open,
	release:keys4_release,
};

static int __init keys4_init(void)
{
	static int rc;
        unsigned long gpfup;

	set_external_irq(IRQ_EINT2,EXT_FALLING_EDGE, GPIO_PULLUP_DIS);
	set_external_irq(IRQ_EINT3,EXT_FALLING_EDGE, GPIO_PULLUP_DIS);
	set_external_irq(IRQ_EINT4,EXT_FALLING_EDGE, GPIO_PULLUP_DIS);
	set_external_irq(IRQ_EINT5,EXT_FALLING_EDGE, GPIO_PULLUP_DIS);
	
        gpfup = ioremap(0x56000058,4);
        (*(volatile unsigned long *)gpfup) &= 0xc3;  //bit2,3,4,5 = 0.

	disable_irq(IRQ_EINT2);
	enable_irq(IRQ_EINT2);
	disable_irq(IRQ_EINT3);
	enable_irq(IRQ_EINT3);
	disable_irq(IRQ_EINT4);
	enable_irq(IRQ_EINT4);
	disable_irq(IRQ_EINT5);
	enable_irq(IRQ_EINT5);


	rc = request_irq(IRQ_EINT5, key1_irq_isr, SA_INTERRUPT, "keys4", NULL);
	if (rc) {
		printk("<1>keys4irq 1 irq not registered. Error: %d\n", rc);
	}
	
	rc = request_irq(IRQ_EINT4, key2_irq_isr, SA_INTERRUPT, "keys4", NULL);
	if (rc) {
		printk("<1>keyirq 2 irq not registered. Error: %d\n", rc);
	}
	
	rc = request_irq(IRQ_EINT3, key3_irq_isr, SA_INTERRUPT, "keys4", NULL);
	if (rc) {
		printk("<1>keyirq 3 irq not registered. Error: %d\n", rc);
	}	
	
	rc = request_irq(IRQ_EINT2, key4_irq_isr, SA_INTERRUPT, "keys4", NULL);
	if (rc) {
		printk("<1>keyirq 4 irq not registered. Error: %d\n", rc);
	}
	
//	disable_irq(IRQ_EINT2);
//	disable_irq(IRQ_EINT3);
//	disable_irq(IRQ_EINT4);
//	disable_irq(IRQ_EINT5);

        printk("*********keys4 init ok!***********\n"); 
      
	/* Register myirq as character device */
        devfs_keys4 = devfs_register(NULL,"keys4",DEVFS_FL_DEFAULT,KEYS4_MAJOR,                              0, S_IFCHR |S_IRUSR |S_IWUSR |S_IRGRP |S_IWGRP,                                 &keys4_fops, NULL);	


/*        if ((rc = register_chrdev(keyirq_MAJOR, "keys4", &keys4_fops)) < 0) {
		printk("keyirq: can't get major %d\n",keyirq_MAJOR);
		return;
	}	
*/				
	return 0;
}

static void __exit keys4_exit(void)
{
        
	disable_irq(IRQ_EINT2);
	disable_irq(IRQ_EINT3);
	disable_irq(IRQ_EINT4);
	disable_irq(IRQ_EINT5);

        free_irq(IRQ_EINT5, key1_irq_isr);
        free_irq(IRQ_EINT4, key2_irq_isr);
        free_irq(IRQ_EINT3, key3_irq_isr);
        free_irq(IRQ_EINT2, key4_irq_isr);

	devfs_unregister(devfs_keys4);

}

module_init(keys4_init);
module_exit(keys4_exit);

//__initcall(keys4_init);