rpckbd.c

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/*
 *  Copyright (c) 2000-2001 Vojtech Pavlik
 *  Copyright (c) 2002 Russell King
 */

/*
 * Acorn RiscPC PS/2 keyboard controller driver for Linux/ARM
 */

/*
 * 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/interrupt.h>
#include <linux/init.h>
#include <linux/serio.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>

#include <mach/hardware.h>
#include <asm/hardware/iomd.h>

MODULE_AUTHOR("Vojtech Pavlik, Russell King");
MODULE_DESCRIPTION("Acorn RiscPC PS/2 keyboard controller driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:kart");

struct rpckbd_data {
    int tx_irq;
    int rx_irq;
};

static int rpckbd_write(struct serio *port, unsigned char val)
{
    while (!(iomd_readb(IOMD_KCTRL) & (1 << 7)))
        cpu_relax();

    iomd_writeb(val, IOMD_KARTTX);

    return 0;
}

static irqreturn_t rpckbd_rx(int irq, void *dev_id)
{
    struct serio *port = dev_id;
    unsigned int byte;
    int handled = IRQ_NONE;

    while (iomd_readb(IOMD_KCTRL) & (1 << 5)) {
        byte = iomd_readb(IOMD_KARTRX);

        serio_interrupt(port, byte, 0);
        handled = IRQ_HANDLED;
    }
    return handled;
}

static irqreturn_t rpckbd_tx(int irq, void *dev_id)
{
    return IRQ_HANDLED;
}

static int rpckbd_open(struct serio *port)
{
    struct rpckbd_data *rpckbd = port->port_data;

    /* Reset the keyboard state machine. */
    iomd_writeb(0, IOMD_KCTRL);
    iomd_writeb(8, IOMD_KCTRL);
    iomd_readb(IOMD_KARTRX);

    if (request_irq(rpckbd->rx_irq, rpckbd_rx, 0, "rpckbd", port) != 0) {
        printk(KERN_ERR "rpckbd.c: Could not allocate keyboard receive IRQ\n");
        return -EBUSY;
    }

    if (request_irq(rpckbd->tx_irq, rpckbd_tx, 0, "rpckbd", port) != 0) {
        printk(KERN_ERR "rpckbd.c: Could not allocate keyboard transmit IRQ\n");
        free_irq(rpckbd->rx_irq, port);
        return -EBUSY;
    }

    return 0;
}

static void rpckbd_close(struct serio *port)
{
    struct rpckbd_data *rpckbd = port->port_data;

    free_irq(rpckbd->rx_irq, port);
    free_irq(rpckbd->tx_irq, port);
}

/*
 * Allocate and initialize serio structure for subsequent registration
 * with serio core.
 */
static int __devinit rpckbd_probe(struct platform_device *dev)
{
    struct rpckbd_data *rpckbd;
    struct serio *serio;
    int tx_irq, rx_irq;

    rx_irq = platform_get_irq(dev, 0);
    if (rx_irq <= 0)
        return rx_irq < 0 ? rx_irq : -ENXIO;

    tx_irq = platform_get_irq(dev, 1);
    if (tx_irq <= 0)
        return tx_irq < 0 ? tx_irq : -ENXIO;

    serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
    rpckbd = kzalloc(sizeof(*rpckbd), GFP_KERNEL);
    if (!serio || !rpckbd) {
        kfree(rpckbd);
        kfree(serio);
        return -ENOMEM;
    }

    rpckbd->rx_irq = rx_irq;
    rpckbd->tx_irq = tx_irq;

    serio->id.type      = SERIO_8042;
    serio->write        = rpckbd_write;
    serio->open     = rpckbd_open;
    serio->close        = rpckbd_close;
    serio->dev.parent   = &dev->dev;
    serio->port_data    = rpckbd;
    strlcpy(serio->name, "RiscPC PS/2 kbd port", sizeof(serio->name));
    strlcpy(serio->phys, "rpckbd/serio0", sizeof(serio->phys));

    platform_set_drvdata(dev, serio);
    serio_register_port(serio);
    return 0;
}

static int __devexit rpckbd_remove(struct platform_device *dev)
{
    struct serio *serio = platform_get_drvdata(dev);
    struct rpckbd_data *rpckbd = serio->port_data;

    serio_unregister_port(serio);
    kfree(rpckbd);

    return 0;
}

static struct platform_driver rpckbd_driver = {
    .probe      = rpckbd_probe,
    .remove     = __devexit_p(rpckbd_remove),
    .driver     = {
        .name   = "kart",
        .owner  = THIS_MODULE,
    },
};
module_platform_driver(rpckbd_driver);