[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>
diff --git a/sound/core/control.c b/sound/core/control.c
index e9c8854..f0c7272 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1375,6 +1375,11 @@
struct snd_card *card = device->device_data;
struct list_head *flist;
struct snd_ctl_file *ctl;
+ int err, cardnum;
+
+ snd_assert(card != NULL, return -ENXIO);
+ cardnum = card->number;
+ snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
down_read(&card->controls_rwsem);
list_for_each(flist, &card->ctl_files) {
@@ -1383,6 +1388,10 @@
kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
}
up_read(&card->controls_rwsem);
+
+ if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
+ card, -1)) < 0)
+ return err;
return 0;
}
@@ -1404,23 +1413,6 @@
}
/*
- * de-registration of the control device
- */
-static int snd_ctl_dev_unregister(struct snd_device *device)
-{
- struct snd_card *card = device->device_data;
- int err, cardnum;
-
- snd_assert(card != NULL, return -ENXIO);
- cardnum = card->number;
- snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
- if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
- card, -1)) < 0)
- return err;
- return snd_ctl_dev_free(device);
-}
-
-/*
* create control core:
* called from init.c
*/
@@ -1430,7 +1422,6 @@
.dev_free = snd_ctl_dev_free,
.dev_register = snd_ctl_dev_register,
.dev_disconnect = snd_ctl_dev_disconnect,
- .dev_unregister = snd_ctl_dev_unregister
};
snd_assert(card != NULL, return -ENXIO);