/*
 * $Id: q40kbd.c,v 1.12 2002/02/02 22:26:44 vojtech Exp $
 *
 *  Copyright (c) 2000-2001 Vojtech Pavlik
 *
 *  Based on the work of:
 *	Richard Zidlicky <Richard.Zidlicky@stud.informatik.uni-erlangen.de>
 */

/*
 * Q40 PS/2 keyboard controller driver for Linux/m68k
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Should you need to contact me, the author, you can do so either by
 * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/serio.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/bitops.h>
#include <linux/platform_device.h>

#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/q40_master.h>
#include <asm/irq.h>
#include <asm/q40ints.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Q40 PS/2 keyboard controller driver");
MODULE_LICENSE("GPL");

DEFINE_SPINLOCK(q40kbd_lock);
static struct serio *q40kbd_port;
static struct platform_device *q40kbd_device;

static irqreturn_t q40kbd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	unsigned long flags;

	spin_lock_irqsave(&q40kbd_lock, flags);

	if (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG))
		serio_interrupt(q40kbd_port, master_inb(KEYCODE_REG), 0, regs);

	master_outb(-1, KEYBOARD_UNLOCK_REG);

	spin_unlock_irqrestore(&q40kbd_lock, flags);

	return IRQ_HANDLED;
}

/*
 * q40kbd_flush() flushes all data that may be in the keyboard buffers
 */

static void q40kbd_flush(void)
{
 	int maxread = 100;
	unsigned long flags;

	spin_lock_irqsave(&q40kbd_lock, flags);

 	while (maxread-- && (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG)))
 		master_inb(KEYCODE_REG);

	spin_unlock_irqrestore(&q40kbd_lock, flags);
}

/*
 * q40kbd_open() is called when a port is open by the higher layer.
 * It allocates the interrupt and enables in in the chip.
 */

static int q40kbd_open(struct serio *port)
{
	q40kbd_flush();

	if (request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0, "q40kbd", NULL)) {
		printk(KERN_ERR "q40kbd.c: Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
		return -1;
	}

 	/* off we go */
 	master_outb(-1, KEYBOARD_UNLOCK_REG);
 	master_outb(1, KEY_IRQ_ENABLE_REG);

 	return 0;
}

static void q40kbd_close(struct serio *port)
{
	master_outb(0, KEY_IRQ_ENABLE_REG);
	master_outb(-1, KEYBOARD_UNLOCK_REG);
	free_irq(Q40_IRQ_KEYBOARD, NULL);

	q40kbd_flush();
}

static struct serio * __init q40kbd_allocate_port(void)
{
	struct serio *serio;

	serio = kmalloc(sizeof(struct serio), GFP_KERNEL);
	if (serio) {
		memset(serio, 0, sizeof(struct serio));
		serio->id.type		= SERIO_8042;
		serio->open		= q40kbd_open;
		serio->close		= q40kbd_close;
		serio->dev.parent	= &q40kbd_device->dev;
		strlcpy(serio->name, "Q40 Kbd Port", sizeof(serio->name));
		strlcpy(serio->phys, "Q40", sizeof(serio->phys));
	}

	return serio;
}

static int __init q40kbd_init(void)
{
	if (!MACH_IS_Q40)
		return -EIO;

	q40kbd_device = platform_device_register_simple("q40kbd", -1, NULL, 0);
	if (IS_ERR(q40kbd_device))
		return PTR_ERR(q40kbd_device);

	if (!(q40kbd_port = q40kbd_allocate_port())) {
		platform_device_unregister(q40kbd_device);
		return -ENOMEM;
	}

	serio_register_port(q40kbd_port);
	printk(KERN_INFO "serio: Q40 kbd registered\n");

	return 0;
}

static void __exit q40kbd_exit(void)
{
	serio_unregister_port(q40kbd_port);
	platform_device_unregister(q40kbd_device);
}

module_init(q40kbd_init);
module_exit(q40kbd_exit);