key.c

该文件是摩托罗拉的嵌入式芯片dragonball MX1的在嵌入式linux下键盘驱动

#define	__KERNEL__
#define	MODULE


/////////////////////////////////////////////////////////////////////////////
#include <linux/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <asm/uaccess.h>        /* get_user,copy_to_user */

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/in.h>
//include <linux/malloc.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/init.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <linux/errno.h>
#include <linux/tqueue.h>
#include <linux/wait.h>
#include <asm/irq.h>
#include <asm/arch/hardware.h>
#include <asm/arch/irqs.h>
#include <linux/devfs_fs_kernel.h>
#include "mx1_def.h"
#include "key.h"


void delay(void);
int key_open(struct inode * inode, struct file * filp);
int key_release(struct inode * inode, struct file * filp);
unsigned int key_poll(struct file * filp, struct poll_table_struct * wait);
int init_key(void);
static void pb_irq_handle(int irq, void *dev_id, struct pt_regs *regs);
void cleanup_key(void);
ssize_t key_read(struct file * filp, char * buf, size_t count, loff_t * l);

char *dev_id="KeyBoardIrq";
#define	V_ADDRESS(x)	(*((volatile unsigned long* )(0xF0000000|x)))

unsigned char  key_val=0xff;
wait_queue_head_t 	ts_wait;

struct file_operations key_fops = {
	open:           key_open,
	release:        key_release,
	read:           key_read,
	poll:           key_poll,
	};


int key_open(struct inode * inode, struct file * filp)
{
	//       enable_irq(12);
	MOD_INC_USE_COUNT;
	return 0;
}

/******************************************************************************
* Function Name: key_release
*
* Input: 		inode	:
* 			filp	:
* Value Returned:	int	: Return status.If no error, return 0.
*
* Description: release resource when close the inode
*
* Modification History:
* 	wang kuo
*****************************************************************************/
int key_release(struct inode * inode,
struct file * filp)
{
	//    disable_irq(12);
	MOD_DEC_USE_COUNT;
	return 0;
}

ssize_t key_read(struct file * filp, char * buf, size_t count, loff_t * l)
{
	copy_to_user(buf, &key_val, 1);
	key_val = 0xff;
	return 0;
}

unsigned int key_poll(struct file * filp, struct poll_table_struct * wait)
{
	poll_wait(filp,&ts_wait,wait);

	if (key_val != 0xff)
	return POLLIN |POLLRDNORM;
	else
	return 0;
}
static void pb_irq_handle(int irq, void *dev_id, struct pt_regs *regs)
{

	unsigned long status_isr=0;
	unsigned long dr_bak=0;
	
	unsigned pta_mask = 0x8000;
	unsigned ptc_mask = 0x10000;
	int i=0;
	unsigned int row=0, col=0;

	if(!((V_ADDRESS(PTA_ISR) & 0x1)||(V_ADDRESS(PTC_ISR) & 0xE000)))	
		return;
	
	// Disable Interruption
	V_ADDRESS(PTA_IMR)  &=~ 0x00000001;	//PA0
	V_ADDRESS(PTC_IMR)  &=~ 0x0000E000;	//PC13, PC14, PC15
	
	// ROW: PC14, PC15, PA0, PC13 
	status_isr |= (V_ADDRESS(PTC_ISR) & 0x2000) >> 13;	                         
	status_isr |= (V_ADDRESS(PTC_ISR) & 0x4000) >> 11;
	status_isr |= (V_ADDRESS(PTC_ISR) & 0x8000) >> 13;
	status_isr |= (V_ADDRESS(PTA_ISR) & 0x1)    <<  1;
	
	V_ADDRESS(PTA_ISR)  |= 0x00000001;
	V_ADDRESS(PTC_ISR)  |= 0x0000E000;
	
	/////////////////////////////////////////////////////////////////////////

	if(status_isr)
	{
		row = (status_isr/2);
		if(row>3)   row =3;

		//PC14、PC15、PA0、PC13
		dr_bak=((V_ADDRESS(PTC_SSR) & 0xE000) | (V_ADDRESS(PTA_SSR) & 0x1));
		
		while(dr_bak == ((V_ADDRESS(PTC_SSR) & 0xE000) | (V_ADDRESS(PTA_SSR) & 0x1)))
		{
			//  PA15、PA16、PC16、PC17
			if(col < 2){
				V_ADDRESS(PTA_DR) &=~0x18000;	
				V_ADDRESS(PTA_DR) |= pta_mask;	
				pta_mask = pta_mask << 1;
			}
			else {
				V_ADDRESS(PTC_DR) &=~0x30000;
				V_ADDRESS(PTC_DR) |= ptc_mask;
				ptc_mask = ptc_mask << 1;
			}
			if(col==4)  break;
			col++;

		}
		col = 4-col;
		if(col<=3 && row<=3)
		{
			printk("Key(%u, %u) pressed!\n",row,col);
			for(;i<2000;i++)
				delay();			
			V_ADDRESS(PTA_DR) &=~0x18000;
			V_ADDRESS(PTC_DR) &=~0x30000;
			key_val = (row << 4) | col;
		}
	}

	///////////////////////////////////////////////////////////////////////////////
	//    restore_flags(flags);

	V_ADDRESS(PTA_IMR)  |= 0x00000001;
	V_ADDRESS(PTC_IMR)  |= 0x0000E000;
	wake_up_interruptible(&ts_wait);
}
void delay(void)
{
	unsigned long i= 1<<12;
	
	for(;i>0;i--){};
}



//////////////////////////////////////////////////////////////////////////////////////////////////
#ifdef MODULE
int init_module(void)
#else
int __init init_key(void)
#endif
{
	unsigned int result = 0;
	init_waitqueue_head(&ts_wait);

	// PA15、PA16、PC16、PC17 OUTPUT
	
	V_ADDRESS(PTA_GIUS) |= 0x18000;		// PA15, PA16
	V_ADDRESS(PTA_OCR1) |= 0xC0000000;	// PA15
	V_ADDRESS(PTA_OCR2) |= 0x3;		// PA16
	V_ADDRESS(PTA_DDIR) |= 0x18000;
	V_ADDRESS(PTA_DR)   &=~0x18000;
	
	V_ADDRESS(PTC_GIUS) |= 0x30000;
	V_ADDRESS(PTC_DDIR) |= 0x30000;
	V_ADDRESS(PTC_OCR2) |= 0xF;		// PC16, PC17
	V_ADDRESS(PTC_DR)   &=~0x30000;
	
	// PC14、PC15、PA0、PC13 INTERRUPT
	V_ADDRESS(PTA_GIUS) |= 0x1;		// PA0
	V_ADDRESS(PTA_DDIR) &=~0x1;
	V_ADDRESS(PTA_ICR1) &=~0x3;
	V_ADDRESS(PTA_ICR1) |= 0x1;
	V_ADDRESS(PTA_ISR)  |= 0x1;

	V_ADDRESS(PTC_GIUS) |= 0xE000;		// PC14, PC15, PC13
	V_ADDRESS(PTC_DDIR) &=~0xE000;
	V_ADDRESS(PTC_ICR1) &=~0xFC000000;
	V_ADDRESS(PTC_ICR1) |= 0x54000000;
	V_ADDRESS(PTC_ISR)  |= 0xE000;

	result = register_chrdev(250, "/tmp/keyBoard", &key_fops);

	if (result < 0) {
		printk("<1>key_dev: can't get major number 250\n");
		unregister_chrdev(250,"keyBoard");
		return result;
	}
	printk("<1>register_chrdev: %d\n", result);
	
	// 
	V_ADDRESS(PTA_IMR)  |= 0x1;	// PA0
	V_ADDRESS(PTC_IMR)  |= 0xE000;	// PC14, PC15, PC13

	result=request_irq(11,pb_irq_handle,SA_SHIRQ,"keyBoard", dev_id);
	result=request_irq(13,pb_irq_handle,SA_SHIRQ,"keyBoard", dev_id);
	
	enable_irq(11);
	enable_irq(13);
	
	printk("<1> request_irq: %d\n", result);
	return 0;
}



#ifdef MODULE
void cleanup_module(void)
#else
void __exit cleanup_key(void)
#endif
{
	disable_irq(11);
	disable_irq(13);
	V_ADDRESS(PTA_IMR)  &=~ 0x00000001;	//PA0
	V_ADDRESS(PTC_IMR)  &=~ 0x0000E000;	//PC13, PC14, PC15
	
	free_irq(11, dev_id);
	free_irq(13, dev_id);
	unregister_chrdev(250,"keyBoard");
}



#ifndef MODULE
module_init(init_key);
module_exit(cleanup_key);
#endif