sh: mach-x3proto: Support for baseboard GPIOs.

obj-y += setup.o ilsel.o

obj-$(CONFIG_GENERIC_GPIO)	+= gpio.o

/*

 * 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_chip *chip = get_irq_desc_chip(desc);

	unsigned long mask;

	int pin;

	chip->mask_ack(irq);

	mask = __raw_readw(KEYDETR);

	for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)

		generic_handle_irq(x3proto_gpio_to_irq(NULL, pin));

	chip->unmask(irq);

}

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)

{

	unsigned 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;

		unsigned 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;

}

#ifndef __MACH_X3PROTO_HARDWARE_H

#define __MACH_X3PROTO_HARDWARE_H

struct gpio_chip;

/* arch/sh/boards/mach-x3proto/gpio.c */

int x3proto_gpio_setup(void);

extern struct gpio_chip x3proto_gpio_chip;

#define NR_BASEBOARD_GPIOS	16

#endif /* __MACH_X3PROTO_HARDWARE_H */