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/**
* snd_card_register - register the soundcard
* @card: soundcard structure
*
* This function registers all the devices assigned to the soundcard.
* Until calling this, the ALSA control interface is blocked from the
* external accesses. Thus, you should call this function at the end
* of the initialization of the card.
*
* Returns zero otherwise a negative error code if the registrain failed.
*/
int snd_card_register(struct snd_card *card)
{
int err;
if (snd_BUG_ON(!card))
return -EINVAL;
#ifndef CONFIG_SYSFS_DEPRECATED
if (!card->card_dev) {
card->card_dev = device_create(sound_class, card->dev,
MKDEV(0, 0), card,
"card%i", card->number);
if (IS_ERR(card->card_dev))
card->card_dev = NULL;
}
#endif
if ((err = snd_device_register_all(card)) < 0)
return err;
mutex_lock(&snd_card_mutex);
if (snd_cards[card->number]) {
/* already registered */
mutex_unlock(&snd_card_mutex);
return 0;
}
snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
snd_cards[card->number] = card;
mutex_unlock(&snd_card_mutex);
init_info_for_card(card);
#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
if (snd_mixer_oss_notify_callback)
snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
#endif
#ifndef CONFIG_SYSFS_DEPRECATED
if (card->card_dev) {
err = device_create_file(card->card_dev, &card_id_attrs);
if (err < 0)
return err;
err = device_create_file(card->card_dev, &card_number_attrs);
if (err < 0)
return err;
}
#endif
return 0;
}
EXPORT_SYMBOL(snd_card_register);
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