u-boot/drivers/gpio/s3c2440_gpio.c
Gabriel Huau 5d889ae79e ARM : Add GPIO Driver and IOMUX definition for S3C2440
It's now possible to use the gpio driver interface
for s3c2440. This patch add iomux definitions too.

Signed-off-by: Gabriel Huau <contact@huau-gabriel.fr>
2012-10-03 10:50:20 +02:00

95 lines
2.4 KiB
C

/*
* Copyright (C) 2012
* Gabriel Huau <contact@huau-gabriel.fr>
*
* 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>
#include <asm/arch/s3c2440.h>
#include <asm/gpio.h>
#include <asm/io.h>
#define GPIO_INPUT 0x0
#define GPIO_OUTPUT 0x1
/* 0x4 means that we want DAT and not CON register */
#define GPIO_PORT(x) ((((x) >> 5) & 0x3) + 0x4)
#define GPIO_BIT(x) ((x) & 0x3f)
/*
* It's how we calculate the full port address
* We have to get the number of the port + 1 (Port A is at 0x56000001 ...)
* We move it at the second digit, and finally we add 0x4 because we want
* to modify GPIO DAT and not CON
*/
#define GPIO_FULLPORT(x) (S3C24X0_GPIO_BASE | ((GPIO_PORT(gpio) + 1) << 1))
int gpio_set_value(unsigned gpio, int value)
{
unsigned l = readl(GPIO_FULLPORT(gpio));
unsigned bit;
unsigned port = GPIO_FULLPORT(gpio);
/*
* All GPIO Port have a configuration on
* 2 bits excepted the first GPIO (A) which
* have only 1 bit of configuration.
*/
if (!GPIO_PORT(gpio))
bit = (0x1 << GPIO_BIT(gpio));
else
bit = (0x3 << GPIO_BIT(gpio));
if (value)
l |= bit;
else
l &= ~bit;
return writel(port, l);
}
int gpio_get_value(unsigned gpio)
{
unsigned l = readl(GPIO_FULLPORT(gpio));
if (GPIO_PORT(gpio) == 0) /* PORT A */
return (l >> GPIO_BIT(gpio)) & 0x1;
return (l >> GPIO_BIT(gpio)) & 0x3;
}
int gpio_request(unsigned gpio, const char *label)
{
return 0;
}
int gpio_free(unsigned gpio)
{
return 0;
}
int gpio_direction_input(unsigned gpio)
{
return writel(GPIO_FULLPORT(gpio), GPIO_INPUT << GPIO_BIT(gpio));
}
int gpio_direction_output(unsigned gpio, int value)
{
writel(GPIO_FULLPORT(gpio), GPIO_OUTPUT << GPIO_BIT(gpio));
return gpio_set_value(gpio, value);
}