linux-sg2042/arch/mips/loongson/common/gpio.c

140 lines
2.8 KiB
C

/*
* STLS2F GPIO Support
*
* Copyright (c) 2008 Richard Liu, STMicroelectronics <richard.liu@st.com>
* Copyright (c) 2008-2010 Arnaud Patard <apatard@mandriva.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/err.h>
#include <asm/types.h>
#include <loongson.h>
#include <linux/gpio.h>
#define STLS2F_N_GPIO 4
#define STLS2F_GPIO_IN_OFFSET 16
static DEFINE_SPINLOCK(gpio_lock);
int gpio_get_value(unsigned gpio)
{
u32 val;
u32 mask;
if (gpio >= STLS2F_N_GPIO)
return __gpio_get_value(gpio);
mask = 1 << (gpio + STLS2F_GPIO_IN_OFFSET);
spin_lock(&gpio_lock);
val = LOONGSON_GPIODATA;
spin_unlock(&gpio_lock);
return ((val & mask) != 0);
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned gpio, int state)
{
u32 val;
u32 mask;
if (gpio >= STLS2F_N_GPIO) {
__gpio_set_value(gpio, state);
return ;
}
mask = 1 << gpio;
spin_lock(&gpio_lock);
val = LOONGSON_GPIODATA;
if (state)
val |= mask;
else
val &= (~mask);
LOONGSON_GPIODATA = val;
spin_unlock(&gpio_lock);
}
EXPORT_SYMBOL(gpio_set_value);
int gpio_cansleep(unsigned gpio)
{
if (gpio < STLS2F_N_GPIO)
return 0;
else
return __gpio_cansleep(gpio);
}
EXPORT_SYMBOL(gpio_cansleep);
static int ls2f_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
u32 temp;
u32 mask;
if (gpio >= STLS2F_N_GPIO)
return -EINVAL;
spin_lock(&gpio_lock);
mask = 1 << gpio;
temp = LOONGSON_GPIOIE;
temp |= mask;
LOONGSON_GPIOIE = temp;
spin_unlock(&gpio_lock);
return 0;
}
static int ls2f_gpio_direction_output(struct gpio_chip *chip,
unsigned gpio, int level)
{
u32 temp;
u32 mask;
if (gpio >= STLS2F_N_GPIO)
return -EINVAL;
gpio_set_value(gpio, level);
spin_lock(&gpio_lock);
mask = 1 << gpio;
temp = LOONGSON_GPIOIE;
temp &= (~mask);
LOONGSON_GPIOIE = temp;
spin_unlock(&gpio_lock);
return 0;
}
static int ls2f_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
return gpio_get_value(gpio);
}
static void ls2f_gpio_set_value(struct gpio_chip *chip,
unsigned gpio, int value)
{
gpio_set_value(gpio, value);
}
static struct gpio_chip ls2f_chip = {
.label = "ls2f",
.direction_input = ls2f_gpio_direction_input,
.get = ls2f_gpio_get_value,
.direction_output = ls2f_gpio_direction_output,
.set = ls2f_gpio_set_value,
.base = 0,
.ngpio = STLS2F_N_GPIO,
};
static int __init ls2f_gpio_setup(void)
{
return gpiochip_add(&ls2f_chip);
}
arch_initcall(ls2f_gpio_setup);