/*
 * digi00x.c - a part of driver for Digidesign Digi 002/003 family
 *
 * Copyright (c) 2014-2015 Takashi Sakamoto
 *
 * Licensed under the terms of the GNU General Public License, version 2.
 */

#include "digi00x.h"

MODULE_DESCRIPTION("Digidesign Digi 002/003 family Driver");
MODULE_AUTHOR("Takashi Sakamoto <o-takashi@sakamocchi.jp>");
MODULE_LICENSE("GPL v2");

#define VENDOR_DIGIDESIGN       0x00a07e
#define MODEL_DIGI00X           0x000002

static int name_card(struct snd_dg00x *dg00x)
{
        struct fw_device *fw_dev = fw_parent_device(dg00x->unit);
        char name[32] = {0};
        char *model;
        int err;

        err = fw_csr_string(dg00x->unit->directory, CSR_MODEL, name,
                            sizeof(name));
        if (err < 0)
                return err;

        model = skip_spaces(name);

        strcpy(dg00x->card->driver, "Digi00x");
        strcpy(dg00x->card->shortname, model);
        strcpy(dg00x->card->mixername, model);
        snprintf(dg00x->card->longname, sizeof(dg00x->card->longname),
                 "Digidesign %s, GUID %08x%08x at %s, S%d", model,
                 fw_dev->config_rom[3], fw_dev->config_rom[4],
                 dev_name(&dg00x->unit->device), 100 << fw_dev->max_speed);

        return 0;
}

static void dg00x_free(struct snd_dg00x *dg00x)
{
        snd_dg00x_stream_destroy_duplex(dg00x);
        snd_dg00x_transaction_unregister(dg00x);

        fw_unit_put(dg00x->unit);

        mutex_destroy(&dg00x->mutex);
}

static void dg00x_card_free(struct snd_card *card)
{
        dg00x_free(card->private_data);
}

static void do_registration(struct work_struct *work)
{
        struct snd_dg00x *dg00x =
                        container_of(work, struct snd_dg00x, dwork.work);
        int err;

        if (dg00x->registered)
                return;

        err = snd_card_new(&dg00x->unit->device, -1, NULL, THIS_MODULE, 0,
                           &dg00x->card);
        if (err < 0)
                return;

        err = name_card(dg00x);
        if (err < 0)
                goto error;

        err = snd_dg00x_stream_init_duplex(dg00x);
        if (err < 0)
                goto error;

        snd_dg00x_proc_init(dg00x);

        err = snd_dg00x_create_pcm_devices(dg00x);
        if (err < 0)
                goto error;

        err = snd_dg00x_create_midi_devices(dg00x);
        if (err < 0)
                goto error;

        err = snd_dg00x_create_hwdep_device(dg00x);
        if (err < 0)
                goto error;

        err = snd_dg00x_transaction_register(dg00x);
        if (err < 0)
                goto error;

        err = snd_card_register(dg00x->card);
        if (err < 0)
                goto error;

        dg00x->card->private_free = dg00x_card_free;
        dg00x->card->private_data = dg00x;
        dg00x->registered = true;

        return;
error:
        snd_dg00x_transaction_unregister(dg00x);
        snd_dg00x_stream_destroy_duplex(dg00x);
        snd_card_free(dg00x->card);
        dev_info(&dg00x->unit->device,
                 "Sound card registration failed: %d\n", err);
}

static int snd_dg00x_probe(struct fw_unit *unit,
                           const struct ieee1394_device_id *entry)
{
        struct snd_dg00x *dg00x;

        /* Allocate this independent of sound card instance. */
        dg00x = kzalloc(sizeof(struct snd_dg00x), GFP_KERNEL);
        if (dg00x == NULL)
                return -ENOMEM;

        dg00x->unit = fw_unit_get(unit);
        dev_set_drvdata(&unit->device, dg00x);

        mutex_init(&dg00x->mutex);
        spin_lock_init(&dg00x->lock);
        init_waitqueue_head(&dg00x->hwdep_wait);

        /* Allocate and register this sound card later. */
        INIT_DEFERRABLE_WORK(&dg00x->dwork, do_registration);
        snd_fw_schedule_registration(unit, &dg00x->dwork);

        return 0;
}

static void snd_dg00x_update(struct fw_unit *unit)
{
        struct snd_dg00x *dg00x = dev_get_drvdata(&unit->device);

        /* Postpone a workqueue for deferred registration. */
        if (!dg00x->registered)
                snd_fw_schedule_registration(unit, &dg00x->dwork);

        snd_dg00x_transaction_reregister(dg00x);

        /*
         * After registration, userspace can start packet streaming, then this
         * code block works fine.
         */
        if (dg00x->registered) {
                mutex_lock(&dg00x->mutex);
                snd_dg00x_stream_update_duplex(dg00x);
                mutex_unlock(&dg00x->mutex);
        }
}

static void snd_dg00x_remove(struct fw_unit *unit)
{
        struct snd_dg00x *dg00x = dev_get_drvdata(&unit->device);

        /*
         * Confirm to stop the work for registration before the sound card is
         * going to be released. The work is not scheduled again because bus
         * reset handler is not called anymore.
         */
        cancel_delayed_work_sync(&dg00x->dwork);

        if (dg00x->registered) {
                /* No need to wait for releasing card object in this context. */
                snd_card_free_when_closed(dg00x->card);
        } else {
                /* Don't forget this case. */
                dg00x_free(dg00x);
        }
}

static const struct ieee1394_device_id snd_dg00x_id_table[] = {
        /* Both of 002/003 use the same ID. */
        {
                .match_flags = IEEE1394_MATCH_VENDOR_ID |
                               IEEE1394_MATCH_MODEL_ID,
                .vendor_id = VENDOR_DIGIDESIGN,
                .model_id = MODEL_DIGI00X,
        },
        {}
};
MODULE_DEVICE_TABLE(ieee1394, snd_dg00x_id_table);

static struct fw_driver dg00x_driver = {
        .driver = {
                .owner = THIS_MODULE,
                .name = "snd-firewire-digi00x",
                .bus = &fw_bus_type,
        },
        .probe    = snd_dg00x_probe,
        .update   = snd_dg00x_update,
        .remove   = snd_dg00x_remove,
        .id_table = snd_dg00x_id_table,
};

static int __init snd_dg00x_init(void)
{
        return driver_register(&dg00x_driver.driver);
}

static void __exit snd_dg00x_exit(void)
{
        driver_unregister(&dg00x_driver.driver);
}

module_init(snd_dg00x_init);
module_exit(snd_dg00x_exit);