// SPDX-License-Identifier: GPL-2.0-only
/*
 *  PC Speaker beeper driver for Linux
 *
 *  Copyright (c) 2002 Vojtech Pavlik
 *  Copyright (c) 1992 Orest Zborowski
 */


#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;
                break;
        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);
        }

        raw_spin_unlock_irqrestore(&i8253_lock, flags);

        return 0;
}

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

        input_unregister_device(pcspkr_dev);
        /* turn off the speaker */
        pcspkr_event(NULL, EV_SND, SND_BELL, 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",
                .pm     = &pcspkr_pm_ops,
        },
        .probe          = pcspkr_probe,
        .remove         = pcspkr_remove,
        .shutdown       = pcspkr_shutdown,
};
module_platform_driver(pcspkr_platform_driver);