[ALSA] Unregister device files at disconnection

Orignally proposed by Sam Revitch <sam.revitch@gmail.com>.
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 <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 9 insertions, 26 deletions

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 51577c22f8ce..8a2bdfae63e3 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -55,7 +55,6 @@ static int snd_rawmidi_free(struct snd_rawmidi *rawmidi);
 static int snd_rawmidi_dev_free(struct snd_device *device);
 static int snd_rawmidi_dev_register(struct snd_device *device);
 static int snd_rawmidi_dev_disconnect(struct snd_device *device);
-static int snd_rawmidi_dev_unregister(struct snd_device *device);
 
 static LIST_HEAD(snd_rawmidi_devices);
 static DEFINE_MUTEX(register_mutex);
@@ -1426,7 +1425,6 @@ int snd_rawmidi_new(struct snd_card *card, char *id, int device,
                 .dev_free = snd_rawmidi_dev_free,
                 .dev_register = snd_rawmidi_dev_register,
                 .dev_disconnect = snd_rawmidi_dev_disconnect,
-                .dev_unregister = snd_rawmidi_dev_unregister
         };
 
         snd_assert(rrawmidi != NULL, return -EINVAL);
@@ -1479,6 +1477,14 @@ static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
 static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
 {
         snd_assert(rmidi != NULL, return -ENXIO);       
+
+        snd_info_free_entry(rmidi->proc_entry);
+        rmidi->proc_entry = NULL;
+        mutex_lock(&register_mutex);
+        if (rmidi->ops && rmidi->ops->dev_unregister)
+                rmidi->ops->dev_unregister(rmidi);
+        mutex_unlock(&register_mutex);
+
         snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
         snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
         if (rmidi->private_free)
@@ -1587,21 +1593,6 @@ static int snd_rawmidi_dev_disconnect(struct snd_device *device)
 
         mutex_lock(&register_mutex);
         list_del_init(&rmidi->list);
-        mutex_unlock(&register_mutex);
-        return 0;
-}
-
-static int snd_rawmidi_dev_unregister(struct snd_device *device)
-{
-        struct snd_rawmidi *rmidi = device->device_data;
-
-        snd_assert(rmidi != NULL, return -ENXIO);
-        mutex_lock(&register_mutex);
-        list_del(&rmidi->list);
-        if (rmidi->proc_entry) {
-                snd_info_free_entry(rmidi->proc_entry);
-                rmidi->proc_entry = NULL;
-        }
 #ifdef CONFIG_SND_OSSEMUL
         if (rmidi->ossreg) {
                 if ((int)rmidi->device == midi_map[rmidi->card->number]) {
@@ -1615,17 +1606,9 @@ static int snd_rawmidi_dev_unregister(struct snd_device *device)
                 rmidi->ossreg = 0;
         }
 #endif /* CONFIG_SND_OSSEMUL */
-        if (rmidi->ops && rmidi->ops->dev_unregister)
-                rmidi->ops->dev_unregister(rmidi);
         snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
         mutex_unlock(&register_mutex);
-#if defined(CONFIG_SND_SEQUENCER) || (defined(MODULE) && defined(CONFIG_SND_SEQUENCER_MODULE))
-        if (rmidi->seq_dev) {
-                snd_device_free(rmidi->card, rmidi->seq_dev);
-                rmidi->seq_dev = NULL;
-        }
-#endif
-        return snd_rawmidi_free(rmidi);
+        return 0;
 }
 
 /**