linux-stable-rt/arch/sh/boards/mach-x3proto/gpio.c

137 lines
3.1 KiB
C

/*
* arch/sh/boards/mach-x3proto/gpio.c
*
* Renesas SH-X3 Prototype Baseboard GPIO Support.
*
* Copyright (C) 2010 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <mach/ilsel.h>
#include <mach/hardware.h>
#define KEYCTLR 0xb81c0000
#define KEYOUTR 0xb81c0002
#define KEYDETR 0xb81c0004
static DEFINE_SPINLOCK(x3proto_gpio_lock);
static unsigned int x3proto_gpio_irq_map[NR_BASEBOARD_GPIOS] = { 0, };
static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
unsigned long flags;
unsigned int data;
spin_lock_irqsave(&x3proto_gpio_lock, flags);
data = __raw_readw(KEYCTLR);
data |= (1 << gpio);
__raw_writew(data, KEYCTLR);
spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
return 0;
}
static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio)
{
return !!(__raw_readw(KEYDETR) & (1 << gpio));
}
static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
{
return x3proto_gpio_irq_map[gpio];
}
static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
{
struct irq_data *data = irq_get_irq_data(irq);
struct irq_chip *chip = irq_data_get_irq_chip(data);
unsigned long mask;
int pin;
chip->irq_mask_ack(data);
mask = __raw_readw(KEYDETR);
for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)
generic_handle_irq(x3proto_gpio_to_irq(NULL, pin));
chip->irq_unmask(data);
}
struct gpio_chip x3proto_gpio_chip = {
.label = "x3proto-gpio",
.direction_input = x3proto_gpio_direction_input,
.get = x3proto_gpio_get,
.to_irq = x3proto_gpio_to_irq,
.base = -1,
.ngpio = NR_BASEBOARD_GPIOS,
};
int __init x3proto_gpio_setup(void)
{
int ilsel;
int ret, i;
ilsel = ilsel_enable(ILSEL_KEY);
if (unlikely(ilsel < 0))
return ilsel;
ret = gpiochip_add(&x3proto_gpio_chip);
if (unlikely(ret))
goto err_gpio;
for (i = 0; i < NR_BASEBOARD_GPIOS; i++) {
unsigned long flags;
int irq = create_irq();
if (unlikely(irq < 0)) {
ret = -EINVAL;
goto err_irq;
}
spin_lock_irqsave(&x3proto_gpio_lock, flags);
x3proto_gpio_irq_map[i] = irq;
set_irq_chip_and_handler_name(irq, &dummy_irq_chip,
handle_simple_irq, "gpio");
spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
}
pr_info("registering '%s' support, handling GPIOs %u -> %u, "
"bound to IRQ %u\n",
x3proto_gpio_chip.label, x3proto_gpio_chip.base,
x3proto_gpio_chip.base + x3proto_gpio_chip.ngpio,
ilsel);
set_irq_chained_handler(ilsel, x3proto_gpio_irq_handler);
set_irq_wake(ilsel, 1);
return 0;
err_irq:
for (; i >= 0; --i)
if (x3proto_gpio_irq_map[i])
destroy_irq(x3proto_gpio_irq_map[i]);
ret = gpiochip_remove(&x3proto_gpio_chip);
if (unlikely(ret))
pr_err("Failed deregistering GPIO\n");
err_gpio:
synchronize_irq(ilsel);
ilsel_disable(ILSEL_KEY);
return ret;
}