[PATCH 4.1 48/78] ALSA: usb-audio: Fix runtime PM unbalance

Greg Kroah-Hartman
2015-09-11T22:58:06Z

From: Takashi Iwai <tiwai@suse.de>

commit 9003ebb13f61e8c78a641e0dda7775183ada0625 upstream.

The fix for deadlock in PM in commit [1ee23fe07ee8: ALSA: usb-audio:
Fix deadlocks at resuming] introduced a new check of in_pm flag.
However, the brainless patch author evaluated it in a wrong way
(logical AND instead of logical OR), thus usb_autopm_get_interface()
is wrongly called at probing, leading to unbalance of runtime PM
refcount.

This patch fixes it by correcting the logic.

Reported-by: Hans Yang <hansy@nvidia.com>
Fixes: 1ee23fe07ee8 ('ALSA: usb-audio: Fix deadlocks at resuming')
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/usb/card.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -638,7 +638,7 @@ int snd_usb_autoresume(struct snd_usb_au
int err = -ENODEV;

down_read(&chip->shutdown_rwsem);
- if (chip->probing && chip->in_pm)
+ if (chip->probing || chip->in_pm)
err = 0;
else if (!chip->shutdown)
err = usb_autopm_get_interface(chip->pm_intf);