diff options
Diffstat (limited to 'sound/core/init.c')
| -rw-r--r-- | sound/core/init.c | 40 |
1 files changed, 22 insertions, 18 deletions
diff --git a/sound/core/init.c b/sound/core/init.c index 079c12d64b0e..db99b7fad6ad 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -1,22 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Initialization routines * Copyright (c) by Jaroslav Kysela <perex@perex.cz> - * - * - * 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/init.h> @@ -49,8 +34,7 @@ static const struct file_operations snd_shutdown_f_ops; /* locked for registering/using */ static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS); -struct snd_card *snd_cards[SNDRV_CARDS]; -EXPORT_SYMBOL(snd_cards); +static struct snd_card *snd_cards[SNDRV_CARDS]; static DEFINE_MUTEX(snd_card_mutex); @@ -268,6 +252,26 @@ int snd_card_new(struct device *parent, int idx, const char *xid, } EXPORT_SYMBOL(snd_card_new); +/** + * snd_card_ref - Get the card object from the index + * @idx: the card index + * + * Returns a card object corresponding to the given index or NULL if not found. + * Release the object via snd_card_unref(). + */ +struct snd_card *snd_card_ref(int idx) +{ + struct snd_card *card; + + mutex_lock(&snd_card_mutex); + card = snd_cards[idx]; + if (card) + get_device(&card->card_dev); + mutex_unlock(&snd_card_mutex); + return card; +} +EXPORT_SYMBOL_GPL(snd_card_ref); + /* return non-zero if a card is already locked */ int snd_card_locked(int card) { |