pcsp.c

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/*
 * PC-Speaker driver for Linux
 *
 * Copyright (C) 1997-2001  David Woodhouse
 * Copyright (C) 2001-2008  Stas Sergeev
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <asm/bitops.h>
#include "pcsp_input.h"
#include "pcsp.h"

MODULE_AUTHOR("Stas Sergeev <[email protected]>");
MODULE_DESCRIPTION("PC-Speaker driver");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{PC-Speaker, pcsp}}");
MODULE_ALIAS("platform:pcspkr");

static int index = SNDRV_DEFAULT_IDX1;  /* Index 0-MAX */
static char *id = SNDRV_DEFAULT_STR1;   /* ID for this card */
static bool enable = SNDRV_DEFAULT_ENABLE1; /* Enable this card */
static bool nopcm;  /* Disable PCM capability of the driver */

module_param(index, int, 0444);
MODULE_PARM_DESC(index, "Index value for pcsp soundcard.");
module_param(id, charp, 0444);
MODULE_PARM_DESC(id, "ID string for pcsp soundcard.");
module_param(enable, bool, 0444);
MODULE_PARM_DESC(enable, "Enable PC-Speaker sound.");
module_param(nopcm, bool, 0444);
MODULE_PARM_DESC(nopcm, "Disable PC-Speaker PCM sound. Only beeps remain.");

struct snd_pcsp pcsp_chip;

static int __devinit snd_pcsp_create(struct snd_card *card)
{
    static struct snd_device_ops ops = { };
    struct timespec tp;
    int err;
    int div, min_div, order;

    if (!nopcm) {
        hrtimer_get_res(CLOCK_MONOTONIC, &tp);
        if (tp.tv_sec || tp.tv_nsec > PCSP_MAX_PERIOD_NS) {
            printk(KERN_ERR "PCSP: Timer resolution is not sufficient "
                "(%linS)\n", tp.tv_nsec);
            printk(KERN_ERR "PCSP: Make sure you have HPET and ACPI "
                "enabled.\n");
            printk(KERN_ERR "PCSP: Turned into nopcm mode.\n");
            nopcm = 1;
        }
    }

    if (loops_per_jiffy >= PCSP_MIN_LPJ && tp.tv_nsec <= PCSP_MIN_PERIOD_NS)
        min_div = MIN_DIV;
    else
        min_div = MAX_DIV;
#if PCSP_DEBUG
    printk(KERN_DEBUG "PCSP: lpj=%li, min_div=%i, res=%li\n",
           loops_per_jiffy, min_div, tp.tv_nsec);
#endif

    div = MAX_DIV / min_div;
    order = fls(div) - 1;

    pcsp_chip.max_treble = min(order, PCSP_MAX_TREBLE);
    pcsp_chip.treble = min(pcsp_chip.max_treble, PCSP_DEFAULT_TREBLE);
    pcsp_chip.playback_ptr = 0;
    pcsp_chip.period_ptr = 0;
    atomic_set(&pcsp_chip.timer_active, 0);
    pcsp_chip.enable = 1;
    pcsp_chip.pcspkr = 1;

    spin_lock_init(&pcsp_chip.substream_lock);

    pcsp_chip.card = card;
    pcsp_chip.port = 0x61;
    pcsp_chip.irq = -1;
    pcsp_chip.dma = -1;

    /* Register device */
    err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, &pcsp_chip, &ops);
    if (err < 0)
        return err;

    return 0;
}

static int __devinit snd_card_pcsp_probe(int devnum, struct device *dev)
{
    struct snd_card *card;
    int err;

    if (devnum != 0)
        return -EINVAL;

    hrtimer_init(&pcsp_chip.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
    pcsp_chip.timer.function = pcsp_do_timer;

    err = snd_card_create(index, id, THIS_MODULE, 0, &card);
    if (err < 0)
        return err;

    err = snd_pcsp_create(card);
    if (err < 0) {
        snd_card_free(card);
        return err;
    }
    if (!nopcm) {
        err = snd_pcsp_new_pcm(&pcsp_chip);
        if (err < 0) {
            snd_card_free(card);
            return err;
        }
    }
    err = snd_pcsp_new_mixer(&pcsp_chip, nopcm);
    if (err < 0) {
        snd_card_free(card);
        return err;
    }

    snd_card_set_dev(pcsp_chip.card, dev);

    strcpy(card->driver, "PC-Speaker");
    strcpy(card->shortname, "pcsp");
    sprintf(card->longname, "Internal PC-Speaker at port 0x%x",
        pcsp_chip.port);

    err = snd_card_register(card);
    if (err < 0) {
        snd_card_free(card);
        return err;
    }

    return 0;
}

static int __devinit alsa_card_pcsp_init(struct device *dev)
{
    int err;

    err = snd_card_pcsp_probe(0, dev);
    if (err) {
        printk(KERN_ERR "PC-Speaker initialization failed.\n");
        return err;
    }

#ifdef CONFIG_DEBUG_PAGEALLOC
    /* Well, CONFIG_DEBUG_PAGEALLOC makes the sound horrible. Lets alert */
    printk(KERN_WARNING "PCSP: CONFIG_DEBUG_PAGEALLOC is enabled, "
           "which may make the sound noisy.\n");
#endif

    return 0;
}

static void __devexit alsa_card_pcsp_exit(struct snd_pcsp *chip)
{
    snd_card_free(chip->card);
}

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

    err = pcspkr_input_init(&pcsp_chip.input_dev, &dev->dev);
    if (err < 0)
        return err;

    err = alsa_card_pcsp_init(&dev->dev);
    if (err < 0) {
        pcspkr_input_remove(pcsp_chip.input_dev);
        return err;
    }

    platform_set_drvdata(dev, &pcsp_chip);
    return 0;
}

static int __devexit pcsp_remove(struct platform_device *dev)
{
    struct snd_pcsp *chip = platform_get_drvdata(dev);
    alsa_card_pcsp_exit(chip);
    pcspkr_input_remove(chip->input_dev);
    platform_set_drvdata(dev, NULL);
    return 0;
}

static void pcsp_stop_beep(struct snd_pcsp *chip)
{
    pcsp_sync_stop(chip);
    pcspkr_stop_sound();
}

#ifdef CONFIG_PM_SLEEP
static int pcsp_suspend(struct device *dev)
{
    struct snd_pcsp *chip = dev_get_drvdata(dev);
    pcsp_stop_beep(chip);
    snd_pcm_suspend_all(chip->pcm);
    return 0;
}

static SIMPLE_DEV_PM_OPS(pcsp_pm, pcsp_suspend, NULL);
#define PCSP_PM_OPS &pcsp_pm
#else
#define PCSP_PM_OPS NULL
#endif  /* CONFIG_PM_SLEEP */

static void pcsp_shutdown(struct platform_device *dev)
{
    struct snd_pcsp *chip = platform_get_drvdata(dev);
    pcsp_stop_beep(chip);
}

static struct platform_driver pcsp_platform_driver = {
    .driver     = {
        .name   = "pcspkr",
        .owner  = THIS_MODULE,
        .pm = PCSP_PM_OPS,
    },
    .probe      = pcsp_probe,
    .remove     = __devexit_p(pcsp_remove),
    .shutdown   = pcsp_shutdown,
};

static int __init pcsp_init(void)
{
    if (!enable)
        return -ENODEV;
    return platform_driver_register(&pcsp_platform_driver);
}

static void __exit pcsp_exit(void)
{
    platform_driver_unregister(&pcsp_platform_driver);
}

module_init(pcsp_init);
module_exit(pcsp_exit);