jack.c

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/*
 *  Jack abstraction layer
 *
 *  Copyright 2008 Wolfson Microelectronics
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/input.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <sound/jack.h>
#include <sound/core.h>

static int jack_switch_types[SND_JACK_SWITCH_TYPES] = {
    SW_HEADPHONE_INSERT,
    SW_MICROPHONE_INSERT,
    SW_LINEOUT_INSERT,
    SW_JACK_PHYSICAL_INSERT,
    SW_VIDEOOUT_INSERT,
    SW_LINEIN_INSERT,
};

static int snd_jack_dev_free(struct snd_device *device)
{
    struct snd_jack *jack = device->device_data;

    if (jack->private_free)
        jack->private_free(jack);

    /* If the input device is registered with the input subsystem
     * then we need to use a different deallocator. */
    if (jack->registered)
        input_unregister_device(jack->input_dev);
    else
        input_free_device(jack->input_dev);

    kfree(jack->id);
    kfree(jack);

    return 0;
}

static int snd_jack_dev_register(struct snd_device *device)
{
    struct snd_jack *jack = device->device_data;
    struct snd_card *card = device->card;
    int err, i;

    snprintf(jack->name, sizeof(jack->name), "%s %s",
         card->shortname, jack->id);
    jack->input_dev->name = jack->name;

    /* Default to the sound card device. */
    if (!jack->input_dev->dev.parent)
        jack->input_dev->dev.parent = snd_card_get_device_link(card);

    /* Add capabilities for any keys that are enabled */
    for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
        int testbit = SND_JACK_BTN_0 >> i;

        if (!(jack->type & testbit))
            continue;

        if (!jack->key[i])
            jack->key[i] = BTN_0 + i;

        input_set_capability(jack->input_dev, EV_KEY, jack->key[i]);
    }

    err = input_register_device(jack->input_dev);
    if (err == 0)
        jack->registered = 1;

    return err;
}

int snd_jack_new(struct snd_card *card, const char *id, int type,
         struct snd_jack **jjack)
{
    struct snd_jack *jack;
    int err;
    int i;
    static struct snd_device_ops ops = {
        .dev_free = snd_jack_dev_free,
        .dev_register = snd_jack_dev_register,
    };

    jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
    if (jack == NULL)
        return -ENOMEM;

    jack->id = kstrdup(id, GFP_KERNEL);

    jack->input_dev = input_allocate_device();
    if (jack->input_dev == NULL) {
        err = -ENOMEM;
        goto fail_input;
    }

    jack->input_dev->phys = "ALSA";

    jack->type = type;

    for (i = 0; i < SND_JACK_SWITCH_TYPES; i++)
        if (type & (1 << i))
            input_set_capability(jack->input_dev, EV_SW,
                         jack_switch_types[i]);

    err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
    if (err < 0)
        goto fail_input;

    *jjack = jack;

    return 0;

fail_input:
    input_free_device(jack->input_dev);
    kfree(jack->id);
    kfree(jack);
    return err;
}
EXPORT_SYMBOL(snd_jack_new);

void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
{
    WARN_ON(jack->registered);

    jack->input_dev->dev.parent = parent;
}
EXPORT_SYMBOL(snd_jack_set_parent);

int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
             int keytype)
{
    int key = fls(SND_JACK_BTN_0) - fls(type);

    WARN_ON(jack->registered);

    if (!keytype || key >= ARRAY_SIZE(jack->key))
        return -EINVAL;

    jack->type |= type;
    jack->key[key] = keytype;

    return 0;
}
EXPORT_SYMBOL(snd_jack_set_key);

void snd_jack_report(struct snd_jack *jack, int status)
{
    int i;

    if (!jack)
        return;

    for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
        int testbit = SND_JACK_BTN_0 >> i;

        if (jack->type & testbit)
            input_report_key(jack->input_dev, jack->key[i],
                     status & testbit);
    }

    for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
        int testbit = 1 << i;
        if (jack->type & testbit)
            input_report_switch(jack->input_dev,
                        jack_switch_types[i],
                        status & testbit);
    }

    input_sync(jack->input_dev);
}
EXPORT_SYMBOL(snd_jack_report);

MODULE_AUTHOR("Mark Brown <[email protected]>");
MODULE_DESCRIPTION("Jack detection support for ALSA");
MODULE_LICENSE("GPL");