ixp4xx-beeper.c

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/*
 * Generic IXP4xx beeper driver
 *
 * Copyright (C) 2005 Tower Technologies
 *
 * based on nslu2-io.c
 *  Copyright (C) 2004 Karen Spearel
 *
 * Author: Alessandro Zummo <[email protected]>
 * Maintainers: http://www.nslu2-linux.org/
 *
 * 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/module.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <mach/hardware.h>

MODULE_AUTHOR("Alessandro Zummo <[email protected]>");
MODULE_DESCRIPTION("ixp4xx beeper driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ixp4xx-beeper");

static DEFINE_SPINLOCK(beep_lock);

static void ixp4xx_spkr_control(unsigned int pin, unsigned int count)
{
    unsigned long flags;

    spin_lock_irqsave(&beep_lock, flags);

     if (count) {
        gpio_line_config(pin, IXP4XX_GPIO_OUT);
        gpio_line_set(pin, IXP4XX_GPIO_LOW);

        *IXP4XX_OSRT2 = (count & ~IXP4XX_OST_RELOAD_MASK) | IXP4XX_OST_ENABLE;
    } else {
        gpio_line_config(pin, IXP4XX_GPIO_IN);
        gpio_line_set(pin, IXP4XX_GPIO_HIGH);

        *IXP4XX_OSRT2 = 0;
    }

    spin_unlock_irqrestore(&beep_lock, flags);
}

static int ixp4xx_spkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
    unsigned int pin = (unsigned int) input_get_drvdata(dev);
    unsigned int count = 0;

    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 = (IXP4XX_TIMER_FREQ / (value * 4)) - 1;

    ixp4xx_spkr_control(pin, count);

    return 0;
}

static irqreturn_t ixp4xx_spkr_interrupt(int irq, void *dev_id)
{
    /* clear interrupt */
    *IXP4XX_OSST = IXP4XX_OSST_TIMER_2_PEND;

    /* flip the beeper output */
    *IXP4XX_GPIO_GPOUTR ^= (1 << (unsigned int) dev_id);

    return IRQ_HANDLED;
}

static int __devinit ixp4xx_spkr_probe(struct platform_device *dev)
{
    struct input_dev *input_dev;
    int err;

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

    input_set_drvdata(input_dev, (void *) dev->id);

    input_dev->name = "ixp4xx beeper",
    input_dev->phys = "ixp4xx/gpio";
    input_dev->id.bustype = BUS_HOST;
    input_dev->id.vendor  = 0x001f;
    input_dev->id.product = 0x0001;
    input_dev->id.version = 0x0100;
    input_dev->dev.parent = &dev->dev;

    input_dev->evbit[0] = BIT_MASK(EV_SND);
    input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
    input_dev->event = ixp4xx_spkr_event;

    err = request_irq(IRQ_IXP4XX_TIMER2, &ixp4xx_spkr_interrupt,
              IRQF_NO_SUSPEND, "ixp4xx-beeper",
              (void *) dev->id);
    if (err)
        goto err_free_device;

    err = input_register_device(input_dev);
    if (err)
        goto err_free_irq;

    platform_set_drvdata(dev, input_dev);

    return 0;

 err_free_irq:
    free_irq(IRQ_IXP4XX_TIMER2, dev);
 err_free_device:
    input_free_device(input_dev);

    return err;
}

static int __devexit ixp4xx_spkr_remove(struct platform_device *dev)
{
    struct input_dev *input_dev = platform_get_drvdata(dev);
    unsigned int pin = (unsigned int) input_get_drvdata(input_dev);

    input_unregister_device(input_dev);
    platform_set_drvdata(dev, NULL);

    /* turn the speaker off */
    disable_irq(IRQ_IXP4XX_TIMER2);
    ixp4xx_spkr_control(pin, 0);

    free_irq(IRQ_IXP4XX_TIMER2, dev);

    return 0;
}

static void ixp4xx_spkr_shutdown(struct platform_device *dev)
{
    struct input_dev *input_dev = platform_get_drvdata(dev);
    unsigned int pin = (unsigned int) input_get_drvdata(input_dev);

    /* turn off the speaker */
    disable_irq(IRQ_IXP4XX_TIMER2);
    ixp4xx_spkr_control(pin, 0);
}

static struct platform_driver ixp4xx_spkr_platform_driver = {
    .driver     = {
        .name   = "ixp4xx-beeper",
        .owner  = THIS_MODULE,
    },
    .probe      = ixp4xx_spkr_probe,
    .remove     = __devexit_p(ixp4xx_spkr_remove),
    .shutdown   = ixp4xx_spkr_shutdown,
};
module_platform_driver(ixp4xx_spkr_platform_driver);