linux-imx

/*

 *  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/input.h>

#include <linux/platform_device.h>

#include <linux/timex.h>

#include <linux/io.h>

​

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");

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 -EINVAL;

​

    switch (code) {

    case SND_BELL:

        if (value)

            value = 1000;

    case SND_TONE:

        break;

    default:

        return -EINVAL;

    }

​

    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);

    }