/*
 *	int0_driver.c - int0 driver ( low-level )
 *	
 *	Author: 	li ming <admin@lumit.org>
 *	Date:		2005-6-12
 *	Copyleft:	http://www.lumit.org
 */

#include "int0_driver.h"
#include "led_api.h"

/*  
; hardware connection
; PIO8	(gpio)
; 1  	(int0)
; so output value = 0x00000100 = (0b0000 0000  0000 0000  0000 0001  0000 0000)
*/

/* set int0 related gpio */
int int0_open( void )
{
	// set gpio's direction: set IOPMOD register mode bit to 0 = input
	IOPMOD = IOPMOD & (~0x00000100);
	
	// unmask the switch interrupt ...........	
	INTMSK &= ~((1<<21) | (1<<0));   
	
	return 0;
}

int int0_read( char * buf, int count )
{	
	// do nothing		
	return count;
}

int int0_write( char * buf, int count )
{	
	// do nothing
	return count;
}

int int0_ioctl( unsigned int cmd, unsigned long arg )
{
	switch( cmd )
	{
		// Enable interrupt request and Unmask PIO8 interrupt
		case	INT0_ENABLE_INTERRUPT:		
			IOPCON 	|= INT0_IO_ENABLE; 
			break;

		// clear int 0 pending interrupts
		case	INT0_CLEAR_INTERRUPT:
			INTPND |= INT0_MASK;
			break;
					
		// set rising edge interrupt
		case	INT0_RISING_EDGE_INTERRUPT:		
		  	IOPCON	|= INT0_IO_RISING_EDGE;		
			break;
		
		// set falling edge interrupt
		case	INT0_FALLING_EDGE_INTERRUPT:	
		  	IOPCON	|= INT0_IO_FALLING_EDGE;
			break;
		
		// set both edge interrupt
		case	INT0_BOTH_EDGE_INTERRUPT:		
		  	IOPCON	|= INT0_IO_BOTH_EDGE;
			break;
				  	
		// set as active high
		case	INT0_ACTIVE_HIGH:
			IOPCON	|= INT0_IO_ACTIVE_HIGH;
			break;
			
		default:
			break;
	}	
	
	return 0;
}

int int0_release( void )
{
	// do nothing 
	return 0;	
}