ALSA: core: Make snd_card_disconnect() return void

All callers from other files ignore the return value of this function.
And it can only ever return a non-zero value if the parameter card is NULL.

Move the check for card being NULL into snd_card_free_when_closed() to keep
the previous behaviour. Note this isn't necessary for
snd_card_disconnect_sync() because if card was NULL in there the dereference
of card for dev_err() would oops the kernel. Replace this by an oops
triggered by the dereference of card for spin_lock_irq().

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Geoff Levand <geoff@infradead.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20230207191907.467756-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/include/sound/core.h b/include/sound/core.h
index 4365c35d038b4cd6fe6ee675d4dbc5bc4bd67739..9a73c60b6f1ea82e95fbfb263a4cf01bb61bcc31 100644 (file)
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -286,7 +286,7 @@ int snd_devm_card_new(struct device *parent, int idx, const char *xid,
                      struct module *module, size_t extra_size,
                      struct snd_card **card_ret);
 
-int snd_card_disconnect(struct snd_card *card);
+void snd_card_disconnect(struct snd_card *card);
 void snd_card_disconnect_sync(struct snd_card *card);
 int snd_card_free(struct snd_card *card);
 int snd_card_free_when_closed(struct snd_card *card);

diff --git a/sound/core/init.c b/sound/core/init.c
index 5377f94eb2111f844e1c439926f1a27bfb728fd4..a03eddab12fe24d53f616467fac7b2b6f26e14b0 100644 (file)
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -489,17 +489,17 @@ static const struct file_operations snd_shutdown_f_ops =
  *  Note: The current implementation replaces all active file->f_op with special
  *        dummy file operations (they do nothing except release).
  */
-int snd_card_disconnect(struct snd_card *card)
+void snd_card_disconnect(struct snd_card *card)
 {
        struct snd_monitor_file *mfile;
 
        if (!card)
-               return -EINVAL;
+               return;
 
        spin_lock(&card->files_lock);
        if (card->shutdown) {
                spin_unlock(&card->files_lock);
-               return 0;
+               return;
        }
        card->shutdown = 1;
 
@@ -548,7 +548,6 @@ int snd_card_disconnect(struct snd_card *card)
        wake_up(&card->power_sleep);
        snd_power_sync_ref(card);
 #endif
-       return 0;       
 }
 EXPORT_SYMBOL(snd_card_disconnect);
 
@@ -563,15 +562,7 @@ EXPORT_SYMBOL(snd_card_disconnect);
  */
 void snd_card_disconnect_sync(struct snd_card *card)
 {
-       int err;
-
-       err = snd_card_disconnect(card);
-       if (err < 0) {
-               dev_err(card->dev,
-                       "snd_card_disconnect error (%d), skipping sync\n",
-                       err);
-               return;
-       }
+       snd_card_disconnect(card);
 
        spin_lock_irq(&card->files_lock);
        wait_event_lock_irq(card->remove_sleep,
@@ -619,9 +610,10 @@ static int snd_card_do_free(struct snd_card *card)
  */
 int snd_card_free_when_closed(struct snd_card *card)
 {
-       int ret = snd_card_disconnect(card);
-       if (ret)
-               return ret;
+       if (!card)
+               return -EINVAL;
+
+       snd_card_disconnect(card);
        put_device(&card->card_dev);
        return 0;
 }