linux/arch/mips/kernel/gpio_txx9.c
Atsushi Nemoto a9aec7fe74 [MIPS] generic txx9 gpio support
This is a board-independent TXx9 gpio API implementation using gpiolib.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-04-28 17:14:31 +01:00

88 lines
2.1 KiB
C

/*
* A gpio chip driver for TXx9 SoCs
*
* Copyright (C) 2008 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
*
* 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/spinlock.h>
#include <linux/gpio.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <asm/txx9pio.h>
static DEFINE_SPINLOCK(txx9_gpio_lock);
static struct txx9_pio_reg __iomem *txx9_pioptr;
static int txx9_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
return __raw_readl(&txx9_pioptr->din) & (1 << offset);
}
static void txx9_gpio_set_raw(unsigned int offset, int value)
{
u32 val;
val = __raw_readl(&txx9_pioptr->dout);
if (value)
val |= 1 << offset;
else
val &= ~(1 << offset);
__raw_writel(val, &txx9_pioptr->dout);
}
static void txx9_gpio_set(struct gpio_chip *chip, unsigned int offset,
int value)
{
unsigned long flags;
spin_lock_irqsave(&txx9_gpio_lock, flags);
txx9_gpio_set_raw(offset, value);
mmiowb();
spin_unlock_irqrestore(&txx9_gpio_lock, flags);
}
static int txx9_gpio_dir_in(struct gpio_chip *chip, unsigned int offset)
{
spin_lock_irq(&txx9_gpio_lock);
__raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset),
&txx9_pioptr->dir);
mmiowb();
spin_unlock_irq(&txx9_gpio_lock);
return 0;
}
static int txx9_gpio_dir_out(struct gpio_chip *chip, unsigned int offset,
int value)
{
spin_lock_irq(&txx9_gpio_lock);
txx9_gpio_set_raw(offset, value);
__raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset),
&txx9_pioptr->dir);
mmiowb();
spin_unlock_irq(&txx9_gpio_lock);
return 0;
}
static struct gpio_chip txx9_gpio_chip = {
.get = txx9_gpio_get,
.set = txx9_gpio_set,
.direction_input = txx9_gpio_dir_in,
.direction_output = txx9_gpio_dir_out,
.label = "TXx9",
};
int __init txx9_gpio_init(unsigned long baseaddr,
unsigned int base, unsigned int num)
{
txx9_pioptr = ioremap(baseaddr, sizeof(struct txx9_pio_reg));
if (!txx9_pioptr)
return -ENODEV;
txx9_gpio_chip.base = base;
txx9_gpio_chip.ngpio = num;
return gpiochip_add(&txx9_gpio_chip);
}