u-boot/drivers/gpio/spear_gpio.c
Stefan Roese 2cb06a4fda GPIO: Add SPEAr GPIO driver
Tested on x600 (SPEAr600).

Signed-off-by: Stefan Roese <sr@denx.de>
2012-07-07 14:07:42 +02:00

102 lines
2.2 KiB
C

/*
* Copyright (C) 2012 Stefan Roese <sr@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
*/
/*
* Driver for SPEAr600 GPIO controller
*/
#include <common.h>
#include <asm/arch/hardware.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <errno.h>
static int gpio_direction(unsigned gpio,
enum gpio_direction direction)
{
struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
u32 val;
val = readl(&regs->gpiodir);
if (direction == GPIO_DIRECTION_OUT)
val |= 1 << gpio;
else
val &= ~(1 << gpio);
writel(val, &regs->gpiodir);
return 0;
}
int gpio_set_value(unsigned gpio, int value)
{
struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
writel(1 << gpio, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
return 0;
}
int gpio_get_value(unsigned gpio)
{
struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
u32 val;
val = readl(&regs->gpiodata[DATA_REG_ADDR(gpio)]);
return !!val;
}
int gpio_request(unsigned gpio, const char *label)
{
if (gpio >= SPEAR_GPIO_COUNT)
return -EINVAL;
return 0;
}
int gpio_free(unsigned gpio)
{
return 0;
}
void gpio_toggle_value(unsigned gpio)
{
gpio_set_value(gpio, !gpio_get_value(gpio));
}
int gpio_direction_input(unsigned gpio)
{
return gpio_direction(gpio, GPIO_DIRECTION_IN);
}
int gpio_direction_output(unsigned gpio, int value)
{
int ret = gpio_direction(gpio, GPIO_DIRECTION_OUT);
if (ret < 0)
return ret;
gpio_set_value(gpio, value);
return 0;
}