[ALSA] Fix disconnection of proc interface

[firefly-linux-kernel-4.4.55.git] / sound / core / init.c

diff --git a/sound/core/init.c b/sound/core/init.c
index 2ff0e5e90865c70e4bce751f03c59b02e2d8ccc0..1ecb029ff4c91b9e8bfda319ae45dbc78ec3f8e5 100644 (file)
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -38,11 +38,11 @@ struct snd_shutdown_f_ops {
        struct snd_shutdown_f_ops *next;
 };
 
-unsigned int snd_cards_lock = 0;       /* locked for registering/using */
-struct snd_card *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL};
+static unsigned int snd_cards_lock;    /* locked for registering/using */
+struct snd_card *snd_cards[SNDRV_CARDS];
 EXPORT_SYMBOL(snd_cards);
 
-DEFINE_RWLOCK(snd_card_rwlock);
+static DEFINE_MUTEX(snd_card_mutex);
 
 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
@@ -112,7 +112,7 @@ struct snd_card *snd_card_new(int idx, const char *xid,
                strlcpy(card->id, xid, sizeof(card->id));
        }
        err = 0;
-       write_lock(&snd_card_rwlock);
+       mutex_lock(&snd_card_mutex);
        if (idx < 0) {
                int idx2;
                for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
@@ -130,12 +130,12 @@ struct snd_card *snd_card_new(int idx, const char *xid,
        else
                err = -ENODEV;
        if (idx < 0 || err < 0) {
-               write_unlock(&snd_card_rwlock);
+               mutex_unlock(&snd_card_mutex);
                snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1);
                goto __error;
        }
        snd_cards_lock |= 1 << idx;             /* lock it */
-       write_unlock(&snd_card_rwlock);
+       mutex_unlock(&snd_card_mutex);
        card->number = idx;
        card->module = module;
        INIT_LIST_HEAD(&card->devices);
@@ -173,6 +173,17 @@ struct snd_card *snd_card_new(int idx, const char *xid,
 
 EXPORT_SYMBOL(snd_card_new);
 
+/* return non-zero if a card is already locked */
+int snd_card_locked(int card)
+{
+       int locked;
+
+       mutex_lock(&snd_card_mutex);
+       locked = snd_cards_lock & (1 << card);
+       mutex_unlock(&snd_card_mutex);
+       return locked;
+}
+
 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
 {
        return -ENODEV;
@@ -240,9 +251,9 @@ int snd_card_disconnect(struct snd_card *card)
        spin_unlock(&card->files_lock);
 
        /* phase 1: disable fops (user space) operations for ALSA API */
-       write_lock(&snd_card_rwlock);
+       mutex_lock(&snd_card_mutex);
        snd_cards[card->number] = NULL;
-       write_unlock(&snd_card_rwlock);
+       mutex_unlock(&snd_card_mutex);
        
        /* phase 2: replace file->f_op with special dummy operations */
        
@@ -299,6 +310,7 @@ int snd_card_disconnect(struct snd_card *card)
        if (err < 0)
                snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
 
+       snd_info_card_disconnect(card);
        return 0;       
 }
 
@@ -321,9 +333,9 @@ int snd_card_free(struct snd_card *card)
 
        if (card == NULL)
                return -EINVAL;
-       write_lock(&snd_card_rwlock);
+       mutex_lock(&snd_card_mutex);
        snd_cards[card->number] = NULL;
-       write_unlock(&snd_card_rwlock);
+       mutex_unlock(&snd_card_mutex);
 
 #ifdef CONFIG_PM
        wake_up(&card->power_sleep);
@@ -349,7 +361,7 @@ int snd_card_free(struct snd_card *card)
        }
        if (card->private_free)
                card->private_free(card);
-       snd_info_unregister(card->proc_id);
+       snd_info_free_entry(card->proc_id);
        if (snd_info_card_free(card) < 0) {
                snd_printk(KERN_WARNING "unable to free card info\n");
                /* Not fatal error */
@@ -359,9 +371,9 @@ int snd_card_free(struct snd_card *card)
                card->s_f_ops = s_f_ops->next;
                kfree(s_f_ops);
        }
-       write_lock(&snd_card_rwlock);
+       mutex_lock(&snd_card_mutex);
        snd_cards_lock &= ~(1 << card->number);
-       write_unlock(&snd_card_rwlock);
+       mutex_unlock(&snd_card_mutex);
        kfree(card);
        return 0;
 }
@@ -497,16 +509,16 @@ int snd_card_register(struct snd_card *card)
        snd_assert(card != NULL, return -EINVAL);
        if ((err = snd_device_register_all(card)) < 0)
                return err;
-       write_lock(&snd_card_rwlock);
+       mutex_lock(&snd_card_mutex);
        if (snd_cards[card->number]) {
                /* already registered */
-               write_unlock(&snd_card_rwlock);
+               mutex_unlock(&snd_card_mutex);
                return 0;
        }
        if (card->id[0] == '\0')
                choose_default_id(card);
        snd_cards[card->number] = card;
-       write_unlock(&snd_card_rwlock);
+       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)
@@ -518,7 +530,7 @@ int snd_card_register(struct snd_card *card)
 EXPORT_SYMBOL(snd_card_register);
 
 #ifdef CONFIG_PROC_FS
-static struct snd_info_entry *snd_card_info_entry = NULL;
+static struct snd_info_entry *snd_card_info_entry;
 
 static void snd_card_info_read(struct snd_info_entry *entry,
                               struct snd_info_buffer *buffer)
@@ -527,7 +539,7 @@ static void snd_card_info_read(struct snd_info_entry *entry,
        struct snd_card *card;
 
        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
-               read_lock(&snd_card_rwlock);
+               mutex_lock(&snd_card_mutex);
                if ((card = snd_cards[idx]) != NULL) {
                        count++;
                        snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
@@ -538,7 +550,7 @@ static void snd_card_info_read(struct snd_info_entry *entry,
                        snd_iprintf(buffer, "                      %s\n",
                                        card->longname);
                }
-               read_unlock(&snd_card_rwlock);
+               mutex_unlock(&snd_card_mutex);
        }
        if (!count)
                snd_iprintf(buffer, "--- no soundcards ---\n");
@@ -552,12 +564,12 @@ void snd_card_info_read_oss(struct snd_info_buffer *buffer)
        struct snd_card *card;
 
        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
-               read_lock(&snd_card_rwlock);
+               mutex_lock(&snd_card_mutex);
                if ((card = snd_cards[idx]) != NULL) {
                        count++;
                        snd_iprintf(buffer, "%s\n", card->longname);
                }
-               read_unlock(&snd_card_rwlock);
+               mutex_unlock(&snd_card_mutex);
        }
        if (!count) {
                snd_iprintf(buffer, "--- no soundcards ---\n");
@@ -575,11 +587,11 @@ static void snd_card_module_info_read(struct snd_info_entry *entry,
        struct snd_card *card;
 
        for (idx = 0; idx < SNDRV_CARDS; idx++) {
-               read_lock(&snd_card_rwlock);
+               mutex_lock(&snd_card_mutex);
                if ((card = snd_cards[idx]) != NULL)
                        snd_iprintf(buffer, "%2i %s\n",
                                    idx, card->module->name);
-               read_unlock(&snd_card_rwlock);
+               mutex_unlock(&snd_card_mutex);
        }
 }
 #endif
@@ -614,9 +626,9 @@ int __init snd_card_info_init(void)
 
 int __exit snd_card_info_done(void)
 {
-       snd_info_unregister(snd_card_info_entry);
+       snd_info_free_entry(snd_card_info_entry);
 #ifdef MODULE
-       snd_info_unregister(snd_card_module_info_entry);
+       snd_info_free_entry(snd_card_module_info_entry);
 #endif
        return 0;
 }