[PATCH] ALSA: firewire-motu: fix unreleased lock warning in hwdep device

[Takashi Sakamoto]

Smatch static analysis tool detects that acquired lock is not released
in hwdep device when condition branch is passed due to no event. It is
unlikely to occur, while fulfilling is preferable for better coding.

Reported-by: Dan Carpenter <error27 at gmail.com>
Fixes: 634ec0b2906e ("ALSA: firewire-motu: notify event for parameter change in register DSP model")
Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/motu/motu-hwdep.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c
index a900fc0e7644..88d1f4b56e4b 100644
--- a/sound/firewire/motu/motu-hwdep.c
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -87,6 +87,10 @@ static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
 			return -EFAULT;
 
 		count = consumed;
+	} else {
+		spin_unlock_irq(&motu->lock);
+
+		count = 0;
 	}
 
 	return count;
-- 
2.37.2