pcsp_input.c

Go to the documentation of this file.

/*
 *  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/init.h>
#include <linux/input.h>
#include <asm/io.h>
#include "pcsp.h"

static void pcspkr_do_sound(unsigned int count)
{
    unsigned long flags;

    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);
}

void pcspkr_stop_sound(void)
{
    pcspkr_do_sound(0);
}

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

    if (atomic_read(&pcsp_chip.timer_active) || !pcsp_chip.pcspkr)
        return 0;

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

    default:
        return -1;
    }

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

    pcspkr_do_sound(count);

    return 0;
}

int __devinit pcspkr_input_init(struct input_dev **rdev, struct device *dev)
{
    int err;

    struct input_dev *input_dev = input_allocate_device();
    if (!input_dev)
        return -ENOMEM;

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

    input_dev->evbit[0] = BIT(EV_SND);
    input_dev->sndbit[0] = BIT(SND_BELL) | BIT(SND_TONE);
    input_dev->event = pcspkr_input_event;

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

    *rdev = input_dev;
    return 0;
}

int pcspkr_input_remove(struct input_dev *dev)
{
    pcspkr_stop_sound();
    input_unregister_device(dev);   /* this also does kfree() */

    return 0;
}