gpio.c.svn-base

RT-Thread是发展中的下一代微内核嵌入式实时操作系统

/*
 * File      : gpio.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, 2007, RT-Thread Develop Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://openlab.rt-thread.com/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2007-03-26     bernard xiong
 */
#include <rtthread.h>
#include <rthw.h>
#include <pxa270.h>

#include "gpio.h"

rt_uint32 rt_hw_gpio_get_function(rt_uint32 gpio)
{
	rt_uint32 rv, io;

	rv = PXA2X0_GPIO_GAFR(gpio) >> PXA2X0_GPIO_FN_SHIFT(gpio);
	rv = rv & PXA2X0_GPIO_FN;

	io = PXA2X0_GPIO_GPDR(gpio);
	if (io & PXA2X0_GPIO_BIT(gpio)) rv |= PXA2X0_GPIO_OUT;

	io = PXA2X0_GPIO_GPLR(gpio);
	if (io & PXA2X0_GPIO_BIT(gpio)) rv |= PXA2X0_GPIO_SET;

	return (rv);
}

rt_uint32 rt_hw_gpio_set_function(rt_uint32 gpio, rt_uint32 fn)
{
	rt_uint32 rv, bit;
	rt_uint32 oldfn;

	oldfn = rt_hw_gpio_get_function(gpio);

	if ((fn & PXA2X0_GPIO_FN) == (oldfn & PXA2X0_GPIO_FN) &&
			(fn & PXA2X0_GPIO_OUT) == (oldfn & PXA2X0_GPIO_OUT))
	{
		/*
		 * The pin's function is not changing.
		 * For Alternate Functions and GPIO input, we can just
		 * return now.
		 * For GPIO output pins, check the initial state is
		 * the same.
		 *
		 * Return 'fn' instead of 'oldfn' so the caller can
		 * reliably detect that we didn't change anything.
		 * (The initial state might be different for non-
		 * GPIO output pins).
		 */
		if (!(fn & PXA2X0_GPIO_OUT) || (fn & PXA2X0_GPIO_SET) == (oldfn & PXA2X0_GPIO_SET))
			return (fn);
	}

	/*
	 * See section 4.1.3.7 of the PXA2x0 Developer's Manual for
	 * the correct procedure for changing GPIO pin functions.
	 */
	bit = PXA2X0_GPIO_BIT(gpio);

	/*
	 * 1. Configure the correct set/clear state of the pin
	 */
	if ((fn & PXA2X0_GPIO_SET)) PXA2X0_GPIO_GPSR(gpio) = bit;
	else PXA2X0_GPIO_GPCR(gpio) = bit;

	/*
	 * 2. Configure the pin as an input or output as appropriate
	 */
	rv = PXA2X0_GPIO_GPDR(gpio) & ~bit;
	if ((fn & PXA2X0_GPIO_OUT)) rv |= bit;
	
	PXA2X0_GPIO_GPDR(gpio) = rv;

	/*
	 * 3. Configure the pin's function
	 */
	fn = ((fn) & PXA2X0_GPIO_FN) << PXA2X0_GPIO_FN_SHIFT(gpio);
	rv = PXA2X0_GPIO_GAFR(gpio) & ~(PXA2X0_GPIO_FN << PXA2X0_GPIO_FN_SHIFT(gpio));
	PXA2X0_GPIO_GAFR(gpio) = rv | ~(fn << PXA2X0_GPIO_FN_SHIFT(gpio));

	return (oldfn);
}

void rt_hw_gpio_interrupt_handler_0(int vector);
void rt_hw_gpio_interrupt_handler_1(int vector);
void rt_hw_gpio_interrupt_handler_n(int vector);

void rt_hw_gpio_init()
{
	/* install interrupt handler */
	rt_hw_interrupt_install(PXA2X0_INT_GPION, rt_hw_gpio_interrupt_handler_n, RT_NULL);
	rt_hw_interrupt_umask(PXA2X0_INT_GPION);
}

void rt_hw_gpio_interrupt_install(int gpio, void (*handler)(int gpio, void* data), void* data)
{
}

void rt_hw_gpio_interrupt_mask(int gpio)
{
}

void rt_hw_gpio_interrupt_umask(int gpio)
{
}

void rt_hw_gpio_interrupt_handler_0(int vector)
{
	/* ack pending interrupt */
	PXA2X0_GPIO_GEDR0 = PXA2X0_GPIO_BIT(0);
}

void rt_hw_gpio_interrupt_handler_1(int vector)
{
	/* ack pending interrupt */
	PXA2X0_GPIO_GEDR1 = PXA2X0_GPIO_BIT(1);
}

extern int rt_hw_kbd_scankeyboard(void);
extern void rt_hw_led_set(rt_uint32 enable);
void rt_hw_gpio_interrupt_handler_n(int vector)
{
	rt_uint32 scan, gedr;
	static rt_uint32 led = 1;
	
	/* get interrupted gpio */
	gedr = PXA2X0_GPIO_GEDR0;
	if (gedr == 0)
	{
		/* try GEDR1 */
		gedr = PXA2X0_GPIO_GEDR1;
		if (gedr ==0)
		{
			/* try GEDR2 */
			gedr = PXA2X0_GPIO_GEDR2;
			if (gedr == 0) return;
			else
			{
				/* ack pending interrupt */
				PXA2X0_GPIO_GEDR2 = gedr;
			}
		}
		else
		{
			/* ack pending interrupt */
			PXA2X0_GPIO_GEDR1 = gedr;
		}
	}
	else
	{
		/* ack pending interrupt */
		PXA2X0_GPIO_GEDR0 = gedr;
	}
	
	scan = rt_hw_kbd_scankeyboard();
	if (scan != -2 && scan != -1)
	{
		rt_kprintf("%d\n", scan);
		scan ++;
		rt_hw_led_set(led);
		
		if (led) led = 0;
		else led = 1;
	}
}