u-boot/drivers/gpio/mx31_gpio.c
Stefano Babic 7d27cd08b4 MX31: add accessor function to get a gpio
The patch adds an accessor function to get the value of a gpio.

Signed-off-by: Stefano Babic <sbabic@denx.de>
2010-04-30 05:23:25 -05:00

88 lines
2 KiB
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>
#include <asm/arch/mx31.h>
#include <asm/arch/mx31-regs.h>
/* GPIO port description */
static unsigned long gpio_ports[] = {
[0] = GPIO1_BASE,
[1] = GPIO2_BASE,
[2] = GPIO3_BASE,
};
int mx31_gpio_direction(unsigned int gpio, enum mx31_gpio_direction direction)
{
unsigned int port = gpio >> 5;
u32 l;
if (port >= ARRAY_SIZE(gpio_ports))
return 1;
gpio &= 0x1f;
l = __REG(gpio_ports[port] + GPIO_GDIR);
switch (direction) {
case MX31_GPIO_DIRECTION_OUT:
l |= 1 << gpio;
break;
case MX31_GPIO_DIRECTION_IN:
l &= ~(1 << gpio);
}
__REG(gpio_ports[port] + GPIO_GDIR) = l;
return 0;
}
void mx31_gpio_set(unsigned int gpio, unsigned int value)
{
unsigned int port = gpio >> 5;
u32 l;
if (port >= ARRAY_SIZE(gpio_ports))
return;
gpio &= 0x1f;
l = __REG(gpio_ports[port] + GPIO_DR);
if (value)
l |= 1 << gpio;
else
l &= ~(1 << gpio);
__REG(gpio_ports[port] + GPIO_DR) = l;
}
int mx31_gpio_get(unsigned int gpio)
{
unsigned int port = gpio >> 5;
u32 l;
if (port >= ARRAY_SIZE(gpio_ports))
return -1;
gpio &= 0x1f;
l = (__REG(gpio_ports[port] + GPIO_DR) >> gpio) & 0x01;
return l;
}