From c461482c8072bb073e6146db320d3da85cdc89ad Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 23 Jun 2006 14:38:23 +0200 Subject: [ALSA] Unregister device files at disconnection Orignally proposed by Sam Revitch . Unregister device files at disconnection to avoid the futher accesses. Also, the dev_unregister callback is removed and replaced with the combination of disconnect + free. A new function snd_card_free_when_closed() is introduced, which is used in USB disconnect callback. Signed-off-by: Takashi Iwai Signed-off-by: Jaroslav Kysela --- sound/core/init.c | 69 +++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 54 insertions(+), 15 deletions(-) (limited to 'sound/core/init.c') diff --git a/sound/core/init.c b/sound/core/init.c index 1ecb029..5850d99 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -327,22 +327,10 @@ EXPORT_SYMBOL(snd_card_disconnect); * Returns zero. Frees all associated devices and frees the control * interface associated to given soundcard. */ -int snd_card_free(struct snd_card *card) +static int snd_card_do_free(struct snd_card *card) { struct snd_shutdown_f_ops *s_f_ops; - if (card == NULL) - return -EINVAL; - mutex_lock(&snd_card_mutex); - snd_cards[card->number] = NULL; - mutex_unlock(&snd_card_mutex); - -#ifdef CONFIG_PM - wake_up(&card->power_sleep); -#endif - /* wait, until all devices are ready for the free operation */ - wait_event(card->shutdown_sleep, card->files == NULL); - #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_FREE); @@ -371,10 +359,55 @@ int snd_card_free(struct snd_card *card) card->s_f_ops = s_f_ops->next; kfree(s_f_ops); } + kfree(card); + return 0; +} + +static int snd_card_free_prepare(struct snd_card *card) +{ + if (card == NULL) + return -EINVAL; + (void) snd_card_disconnect(card); mutex_lock(&snd_card_mutex); + snd_cards[card->number] = NULL; snd_cards_lock &= ~(1 << card->number); mutex_unlock(&snd_card_mutex); - kfree(card); +#ifdef CONFIG_PM + wake_up(&card->power_sleep); +#endif + return 0; +} + +int snd_card_free_when_closed(struct snd_card *card) +{ + int free_now = 0; + int ret = snd_card_free_prepare(card); + if (ret) + return ret; + + spin_lock(&card->files_lock); + if (card->files == NULL) + free_now = 1; + else + card->free_on_last_close = 1; + spin_unlock(&card->files_lock); + + if (free_now) + snd_card_do_free(card); + return 0; +} + +EXPORT_SYMBOL(snd_card_free_when_closed); + +int snd_card_free(struct snd_card *card) +{ + int ret = snd_card_free_prepare(card); + if (ret) + return ret; + + /* wait, until all devices are ready for the free operation */ + wait_event(card->shutdown_sleep, card->files == NULL); + snd_card_do_free(card); return 0; } @@ -718,6 +751,7 @@ EXPORT_SYMBOL(snd_card_file_add); int snd_card_file_remove(struct snd_card *card, struct file *file) { struct snd_monitor_file *mfile, *pfile = NULL; + int last_close = 0; spin_lock(&card->files_lock); mfile = card->files; @@ -732,9 +766,14 @@ int snd_card_file_remove(struct snd_card *card, struct file *file) pfile = mfile; mfile = mfile->next; } - spin_unlock(&card->files_lock); if (card->files == NULL) + last_close = 1; + spin_unlock(&card->files_lock); + if (last_close) { wake_up(&card->shutdown_sleep); + if (card->free_on_last_close) + snd_card_do_free(card); + } if (!mfile) { snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file); return -ENOENT; -- cgit v1.1