u-boot/drivers/gpio/mxc_gpio.c

/*
 * Copyright (C) 2009
 * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */
#include <common.h>
#ifdef CONFIG_MX31
#include <asm/arch/mx31-regs.h>
#endif
#ifdef CONFIG_MX51
#include <asm/arch/imx-regs.h>
#endif
#include <asm/io.h>
#include <mxc_gpio.h>

/* GPIO port description */
static unsigned long gpio_ports[] = {
	[0] = GPIO1_BASE_ADDR,
	[1] = GPIO2_BASE_ADDR,
	[2] = GPIO3_BASE_ADDR,
#ifdef CONFIG_MX51
	[3] = GPIO4_BASE_ADDR,
#endif
};

int mxc_gpio_direction(unsigned int gpio, enum mxc_gpio_direction direction)
{
	unsigned int port = gpio >> 5;
	struct gpio_regs *regs;
	u32 l;

	if (port >= ARRAY_SIZE(gpio_ports))
		return 1;

	gpio &= 0x1f;

	regs = (struct gpio_regs *)gpio_ports[port];

	l = readl(&regs->gpio_dir);

	switch (direction) {
	case MXC_GPIO_DIRECTION_OUT:
		l |= 1 << gpio;
		break;
	case MXC_GPIO_DIRECTION_IN:
		l &= ~(1 << gpio);
	}
	writel(l, &regs->gpio_dir);

	return 0;
}

void mxc_gpio_set(unsigned int gpio, unsigned int value)
{
	unsigned int port = gpio >> 5;
	struct gpio_regs *regs;
	u32 l;

	if (port >= ARRAY_SIZE(gpio_ports))
		return;

	gpio &= 0x1f;

	regs = (struct gpio_regs *)gpio_ports[port];

	l = readl(&regs->gpio_dr);
	if (value)
		l |= 1 << gpio;
	else
		l &= ~(1 << gpio);
	writel(l, &regs->gpio_dr);
}

int mxc_gpio_get(unsigned int gpio)
{
	unsigned int port = gpio >> 5;
	struct gpio_regs *regs;
	u32 l;

	if (port >= ARRAY_SIZE(gpio_ports))
		return -1;

	gpio &= 0x1f;

	regs = (struct gpio_regs *)gpio_ports[port];

	l = (readl(&regs->gpio_dr) >> gpio) & 0x01;

	return l;
}