pcspkr.c

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/*
 *  PC Speaker beeper driver for Linux
 *
 *  Copyright (c) 2002 Vojtech Pavlik
 *  Copyright (c) 1992 Orest Zborowski
 *
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i8253.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/platform_device.h>
#include <linux/timex.h>
#include <asm/io.h>

MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
MODULE_DESCRIPTION("PC Speaker beeper driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pcspkr");

static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
    unsigned int count = 0;
    unsigned long flags;

    if (type != EV_SND)
        return -1;

    switch (code) {
        case SND_BELL: if (value) value = 1000;
        case SND_TONE: break;
        default: return -1;
    }

    if (value > 20 && value < 32767)
        count = PIT_TICK_RATE / value;

    raw_spin_lock_irqsave(&i8253_lock, flags);

    if (count) {
        /* set command for counter 2, 2 byte write */
        outb_p(0xB6, 0x43);
        /* select desired HZ */
        outb_p(count & 0xff, 0x42);
        outb((count >> 8) & 0xff, 0x42);
        /* enable counter 2 */
        outb_p(inb_p(0x61) | 3, 0x61);
    } else {
        /* disable counter 2 */
        outb(inb_p(0x61) & 0xFC, 0x61);
    }

    raw_spin_unlock_irqrestore(&i8253_lock, flags);

    return 0;
}

static int __devinit pcspkr_probe(struct platform_device *dev)
{
    struct input_dev *pcspkr_dev;
    int err;

    pcspkr_dev = input_allocate_device();
    if (!pcspkr_dev)
        return -ENOMEM;

    pcspkr_dev->name = "PC Speaker";
    pcspkr_dev->phys = "isa0061/input0";
    pcspkr_dev->id.bustype = BUS_ISA;
    pcspkr_dev->id.vendor = 0x001f;
    pcspkr_dev->id.product = 0x0001;
    pcspkr_dev->id.version = 0x0100;
    pcspkr_dev->dev.parent = &dev->dev;

    pcspkr_dev->evbit[0] = BIT_MASK(EV_SND);
    pcspkr_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
    pcspkr_dev->event = pcspkr_event;

    err = input_register_device(pcspkr_dev);
    if (err) {
        input_free_device(pcspkr_dev);
        return err;
    }

    platform_set_drvdata(dev, pcspkr_dev);

    return 0;
}

static int __devexit pcspkr_remove(struct platform_device *dev)
{
    struct input_dev *pcspkr_dev = platform_get_drvdata(dev);

    input_unregister_device(pcspkr_dev);
    platform_set_drvdata(dev, NULL);
    /* turn off the speaker */
    pcspkr_event(NULL, EV_SND, SND_BELL, 0);

    return 0;
}

static int pcspkr_suspend(struct device *dev)
{
    pcspkr_event(NULL, EV_SND, SND_BELL, 0);

    return 0;
}

static void pcspkr_shutdown(struct platform_device *dev)
{
    /* turn off the speaker */
    pcspkr_event(NULL, EV_SND, SND_BELL, 0);
}

static const struct dev_pm_ops pcspkr_pm_ops = {
    .suspend = pcspkr_suspend,
};

static struct platform_driver pcspkr_platform_driver = {
    .driver     = {
        .name   = "pcspkr",
        .owner  = THIS_MODULE,
        .pm = &pcspkr_pm_ops,
    },
    .probe      = pcspkr_probe,
    .remove     = __devexit_p(pcspkr_remove),
    .shutdown   = pcspkr_shutdown,
};
module_platform_driver(pcspkr_platform_driver);