s3c2440_kb.c

键盘驱动程序

		if(key_changed())
		{
			pre_keyboard_code = curr_keyboard_code;
			save_key_to_queue(pre_keyboard_code);
			//printk("KEY_DOWN:%d		x=%d		y =%d\n",timeCount,x,y);
			//设置自动重复开始延时定时器
			/*repeat_timer.expires = jiffies + REPEAT_START_DELAY;
			add_timer(&repeat_timer);*/
			
		}
		
		timeCount=1;
		memset(snap_keyboard_code,0,12*sizeof(u_short));
		//curr_keyboard_code =0;
		
		kb_timer.expires = jiffies + KB_TIMER_DELAY;
		add_timer(&kb_timer);
		
		

	}
	else
	{
		//printk("snap_keyboard_code=%d, %d, %d, %d\n", snap_keyboard_code[3][0],snap_keyboard_code[3][1],snap_keyboard_code[3][2],snap_keyboard_code[3][3]);
		kb_timer.expires = jiffies + KB_TIMER_DELAY;
		add_timer(&kb_timer);

		//printk("timeCount:%d\n",timeCount);
		
		if (timeCount==TIME_OUT) //扫描5次后仍然没有得到稳定键值
		{
			//复位计数器
			timeCount=1;
			kbdev.keyStatus =KEY_UP;
			//使能中断
			enableIrq();
			//关闭定时器
			del_timer(&kb_timer);

			del_timer(&repeat_timer);
			//printk("enable irq \n\n\n");
			curr_keyboard_code = 0;
			pre_keyboard_code= 0 ;
			memset(snap_keyboard_code,0,12*sizeof(u_short));
		}
		else
			timeCount++;
	}
	
	spin_unlock_irq(&(kbdev.lock));
	
}

/*----------------------------------------------------
*  func:  从循环队列中读取按键的键码

*  param: 


*  return: 按键的键码
*                   
------------------------------------------------------*/
static inline int kbRead()
{
	u_short keyvalue;

	spin_lock_irq(&(kbdev.lock));
	
	 keyvalue = BUF_TAIL;

	INCBUF(kbdev.tail );

	spin_unlock_irq(&(tsdev.lock));

	return keyvalue;
}

/*----------------------------------------------------
*  func:  对应文件读的函数,如果循环队列中有键码,
		  则将键码拷贝到用户空间的buffer中
*  param: 
*        

*  return: 
*         返回从循环队列中读取的键码的字节数
*
*                   
------------------------------------------------------*/

static ssize_t
S3C2440_kb_read(struct file *filp, char *buffer, size_t count, loff_t * ppos)
{
	u_short keyvalue;
	if(kbdev.head == kbdev.tail)
	{
		
		return 0;
	}
	else
	{
		
		keyvalue = kbRead();
		count = sizeof(keyvalue);
		/*将数据拷贝到用户空间*/
		copy_to_user(buffer,&(keyvalue),count);
		return count;
	}

	
}

/*----------------------------------------------------
*  func:  与打开文件对应的open函数,初始化全局变量和定
*         时器以及请求中断
*  param: 
*        
*
*  return: 
*                   
------------------------------------------------------*/

static int S3C2440_kb_open(struct inode *inode, struct file *filp)
{

	kbdev.keyStatus = KEY_UP;
	kbdev.head=kbdev.tail = 0;
	kbdev.lock = SPIN_LOCK_UNLOCKED;
	repeat_lock = SPIN_LOCK_UNLOCKED;

	output_giop(0);

	//初始化定时器
	init_timer(&kb_timer);
	kb_timer.function = kb_timer_handler;

	//初始化重复按键定时器	
	init_timer(&repeat_timer);
	repeat_timer.function = repeat_timer_handler;


	/*if(requestIrq() !=0)
		return -1;*/
	enableIrq();

	MOD_INC_USE_COUNT;

	return 0;
}



static struct file_operations kb_fops = {
      owner:	THIS_MODULE,
      open:	    S3C2440_kb_open,
      read:	    S3C2440_kb_read,
      release:	s3c2440_kb_release,
};

/*----------------------------------------------------
*  func:  中断处理程序,关闭中断开启键盘扫描定时器
*  param: 
*        
*
*  return: 
*                   
------------------------------------------------------*/
static void keyboard_interrupt(int irq, void *dev_id, struct pt_regs *regs)

{   
	
	spin_lock_irq(&kbdev.lock);

	//禁止所有中断
	disable_irq(IRQ_EINT1);
	disable_irq(IRQ_EINT3);
	disable_irq(IRQ_EINT8);
	
	kbdev.irq = irq;
	//printk("irq=%d\n",kbdev.irq);

	//启动定时器
	kb_timer.expires = jiffies + KB_TIMER_DELAY;
	add_timer(&kb_timer);

	repeat_timer.expires = jiffies + REPEAT_START_DELAY;
	add_timer(&repeat_timer);

	
	
	spin_unlock_irq(&kbdev.lock);
}
/*----------------------------------------------------
*  func:  初始化eint中断相关寄存器,安装中断处理程序
*  param: 
*        
*
*  return: 
*                   
------------------------------------------------------*/
static int requestIrq()
{
	int ret;
	/* Enable  interrupt */
	//==================================================
	//  irq:	Linux中断号，与硬件中断号不同				
	//  handle: 中断处理程序							
	//  flag:   SA_INTERRUPT指示这是个快速中断处理程序	
	//  dev_id: 用于共享的中断信号线,通常设置成NULL  
	//===================================================
	
	ret = set_external_irq(IRQ_EINT1,EXT_FALLING_EDGE,GPIO_PULLUP_DIS);
	if(ret)
		goto eint_failed ;

	ret = request_irq(IRQ_EINT1, keyboard_interrupt, SA_INTERRUPT,
			  DEVICE_NAME, NULL);
    
	if(ret)
		goto eint1_failed;
	ret = set_external_irq(IRQ_EINT8,EXT_FALLING_EDGE,GPIO_PULLUP_DIS);  //EXT_LOWLEVEL
	if(ret)
		goto eint_failed;

	ret = request_irq(IRQ_EINT8, keyboard_interrupt, SA_INTERRUPT,
			  DEVICE_NAME, NULL);
	if(ret)
		goto eint8_failed;

	ret = set_external_irq(IRQ_EINT3,EXT_FALLING_EDGE,GPIO_PULLUP_DIS);
	if(ret)
		goto eint_failed;

	ret = request_irq(IRQ_EINT3, keyboard_interrupt, SA_INTERRUPT,
			  DEVICE_NAME, NULL);
	if(ret)
		goto eint3_failed;

	return 0;

eint3_failed:
	free_irq(IRQ_EINT3, keyboard_interrupt);
eint8_failed:
	free_irq(IRQ_EINT8, keyboard_interrupt);
eint1_failed:
	free_irq(IRQ_EINT1, keyboard_interrupt);

eint_failed:

	printk(DEVICE_NAME ": IRQ Requeset Error\n");

	return ret;

}


static int s3c2440_kb_release(struct inode *inode, struct file *filp)
{
		/*注销设备*/
//	unregister_chrdev(kbMajor, DEVICE_NAME);

    /*释放中断*/
/*
	free_irq(IRQ_EINT1,NULL);

	free_irq(IRQ_EINT8,NULL);

	free_irq(IRQ_EINT3,NULL);

	MOD_DEC_USE_COUNT;
*/
	return 0;
}

/*----------------------------------------------------
*  func: 初始化键盘驱动,注册字符设备
*  param: 
*        
*
*  return: 
			>=0 : 初始化键盘驱动成功
			<0: 失败
*                   
------------------------------------------------------*/
static int __init s3c2440_kb_init(void)
{
	int ret;

	/*初始化管腿配置*/

	init_gpjcon();

	output_giop(0);

	
	
	/*注册设备*/
	ret = register_chrdev(99, DEVICE_NAME, &kb_fops);
	if(ret < 0) {
		printk(DEVICE_NAME " can't get major number\n");
		return ret;
	}
	kbMajor = ret;

	printk("%s: major number=99\n",DEVICE_NAME);

	requestIrq();
	
	//暂时禁止所有中断，等到open时再打开
	disable_irq(IRQ_EINT1);
	disable_irq(IRQ_EINT3);
	disable_irq(IRQ_EINT8);

	return 0;
}

/*----------------------------------------------------
*  func: 注销字符设备,释放中断
*  param: 
*        
*
*  return: 
			
*                   
------------------------------------------------------*/
static void __exit s3c2440_kb_exit(void)
{
	
	/*注销设备*/
	unregister_chrdev(kbMajor, DEVICE_NAME);
	printk("exit\n");

    /*释放中断*/
	free_irq(IRQ_EINT1,NULL);

	free_irq(IRQ_EINT8,NULL);

	free_irq(IRQ_EINT3,NULL);
}

module_init(s3c2440_kb_init);
module_exit(s3c2440_kb_exit);

//EXPORT_SYMBOL(s3c2440_kb_init);
//EXPORT_SYMBOL(s3c2440_kb_exit);