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// SPDX-License-Identifier: GPL-2.0
/*
* arch/sh/boards/mach-x3proto/gpio.c
*
* Renesas SH-X3 Prototype Baseboard GPIO Support.
*
* Copyright (C) 2010 - 2012 Paul Mundt
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/gpio/driver.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/irqdomain.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 struct irq_domain *x3proto_irq_domain;
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)
{
int virq;
if (gpio < chip->ngpio)
virq = irq_create_mapping(x3proto_irq_domain, gpio);
else
virq = -ENXIO;
return virq;
}
static void x3proto_gpio_irq_handler(struct irq_desc *desc)
{
struct irq_data *data = irq_desc_get_irq_data(desc);
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(irq_linear_revmap(x3proto_irq_domain, 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,
};
static int x3proto_gpio_irq_map(struct irq_domain *domain, unsigned int virq,
irq_hw_number_t hwirq)
{
irq_set_chip_and_handler_name(virq, &dummy_irq_chip, handle_simple_irq,
"gpio");
return 0;
}
static struct irq_domain_ops x3proto_gpio_irq_ops = {
.map = x3proto_gpio_irq_map,
.xlate = irq_domain_xlate_twocell,
};
int __init x3proto_gpio_setup(void)
{
int ilsel, ret;
ilsel = ilsel_enable(ILSEL_KEY);
if (unlikely(ilsel < 0))
return ilsel;
ret = gpiochip_add_data(&x3proto_gpio_chip, NULL);
if (unlikely(ret))
goto err_gpio;
x3proto_irq_domain = irq_domain_add_linear(NULL, NR_BASEBOARD_GPIOS,
&x3proto_gpio_irq_ops, NULL);
if (unlikely(!x3proto_irq_domain))
goto err_irq;
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);
irq_set_chained_handler(ilsel, x3proto_gpio_irq_handler);
irq_set_irq_wake(ilsel, 1);
return 0;
err_irq:
gpiochip_remove(&x3proto_gpio_chip);
ret = 0;
err_gpio:
synchronize_irq(ilsel);
ilsel_disable(ILSEL_KEY);
return ret;
}