q40kbd.c

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/*
 *  Copyright (c) 2000-2001 Vojtech Pavlik
 *
 *  Based on the work of:
 *  Richard Zidlicky <[email protected]>
 */

/*
 * 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 <[email protected]>, 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 <linux/slab.h>

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

#define DRV_NAME    "q40kbd"

MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
MODULE_DESCRIPTION("Q40 PS/2 keyboard controller driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);

struct q40kbd {
    struct serio *port;
    spinlock_t lock;
};

static irqreturn_t q40kbd_interrupt(int irq, void *dev_id)
{
    struct q40kbd *q40kbd = dev_id;
    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);

    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(struct q40kbd *q40kbd)
{
    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);
}

static void q40kbd_stop(void)
{
    master_outb(0, KEY_IRQ_ENABLE_REG);
    master_outb(-1, KEYBOARD_UNLOCK_REG);
}

/*
 * 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)
{
    struct q40kbd *q40kbd = port->port_data;

    q40kbd_flush(q40kbd);

    /* 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)
{
    struct q40kbd *q40kbd = port->port_data;

    q40kbd_stop();
    q40kbd_flush(q40kbd);
}

static int __devinit q40kbd_probe(struct platform_device *pdev)
{
    struct q40kbd *q40kbd;
    struct serio *port;
    int error;

    q40kbd = kzalloc(sizeof(struct q40kbd), GFP_KERNEL);
    port = kzalloc(sizeof(struct serio), GFP_KERNEL);
    if (!q40kbd || !port) {
        error = -ENOMEM;
        goto err_free_mem;
    }

    q40kbd->port = port;
    spin_lock_init(&q40kbd->lock);

    port->id.type = SERIO_8042;
    port->open = q40kbd_open;
    port->close = q40kbd_close;
    port->port_data = q40kbd;
    port->dev.parent = &pdev->dev;
    strlcpy(port->name, "Q40 Kbd Port", sizeof(port->name));
    strlcpy(port->phys, "Q40", sizeof(port->phys));

    q40kbd_stop();

    error = request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0,
                DRV_NAME, q40kbd);
    if (error) {
        dev_err(&pdev->dev, "Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
        goto err_free_mem;
    }

    serio_register_port(q40kbd->port);

    platform_set_drvdata(pdev, q40kbd);
    printk(KERN_INFO "serio: Q40 kbd registered\n");

    return 0;

err_free_mem:
    kfree(port);
    kfree(q40kbd);
    return error;
}

static int __devexit q40kbd_remove(struct platform_device *pdev)
{
    struct q40kbd *q40kbd = platform_get_drvdata(pdev);

    /*
     * q40kbd_close() will be called as part of unregistering
     * and will ensure that IRQ is turned off, so it is safe
     * to unregister port first and free IRQ later.
     */
    serio_unregister_port(q40kbd->port);
    free_irq(Q40_IRQ_KEYBOARD, q40kbd);
    kfree(q40kbd);

    platform_set_drvdata(pdev, NULL);
    return 0;
}

static struct platform_driver q40kbd_driver = {
    .driver     = {
        .name   = "q40kbd",
        .owner  = THIS_MODULE,
    },
    .remove     = __devexit_p(q40kbd_remove),
};

static int __init q40kbd_init(void)
{
    return platform_driver_probe(&q40kbd_driver, q40kbd_probe);
}

static void __exit q40kbd_exit(void)
{
    platform_driver_unregister(&q40kbd_driver);
}

module_init(q40kbd_init);
module_exit(q40kbd_exit);