openwrt/target/linux/ramips/files/arch/mips/ralink/common/gpio.c

115 lines
2.7 KiB
C

/*
* Ralink SoC specific GPIO support
*
* Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/io.h>
#include <asm/mach-ralink/ramips_gpio.h>
#include <ralink_soc.h>
static inline struct ramips_gpio_chip *to_ramips_gpio(struct gpio_chip *chip)
{
struct ramips_gpio_chip *rg;
rg = container_of(chip, struct ramips_gpio_chip, chip);
return rg;
}
static inline void ramips_gpio_wr(struct ramips_gpio_chip *rg, u8 reg, u32 val)
{
__raw_writel(val, rg->regs_base + rg->regs[reg]);
}
static inline u32 ramips_gpio_rr(struct ramips_gpio_chip *rg, u8 reg)
{
return __raw_readl(rg->regs_base + rg->regs[reg]);
}
static int ramips_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
unsigned long flags;
u32 t;
spin_lock_irqsave(&rg->lock, flags);
t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR);
t &= ~(1 << offset);
ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t);
spin_unlock_irqrestore(&rg->lock, flags);
return 0;
}
static int ramips_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
unsigned long flags;
u32 reg;
u32 t;
reg = (value) ? RAMIPS_GPIO_REG_SET : RAMIPS_GPIO_REG_RESET;
spin_lock_irqsave(&rg->lock, flags);
ramips_gpio_wr(rg, reg, 1 << offset);
t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR);
t |= 1 << offset;
ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t);
spin_unlock_irqrestore(&rg->lock, flags);
return 0;
}
static void ramips_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
u32 reg;
reg = (value) ? RAMIPS_GPIO_REG_SET : RAMIPS_GPIO_REG_RESET;
ramips_gpio_wr(rg, reg, 1 << offset);
}
static int ramips_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
u32 t;
t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DATA);
return !!(t & (1 << offset));
}
static __init void ramips_gpio_chip_add(struct ramips_gpio_chip *rg)
{
spin_lock_init(&rg->lock);
rg->regs_base = ioremap(rg->map_base, rg->map_size);
rg->chip.direction_input = ramips_gpio_direction_input;
rg->chip.direction_output = ramips_gpio_direction_output;
rg->chip.get = ramips_gpio_get;
rg->chip.set = ramips_gpio_set;
/* set polarity to low for all lines */
ramips_gpio_wr(rg, RAMIPS_GPIO_REG_POL, 0);
gpiochip_add(&rg->chip);
}
__init int ramips_gpio_init(struct ramips_gpio_data *data)
{
int i;
for (i = 0; i < data->num_chips; i++)
ramips_gpio_chip_add(&data->chips[i]);
return 0;
}