ALSA: AACI: fix multiple IRQ claiming

Claiming the IRQ each time a playback or capture interface is opened
is wasteful; the second copy of the registered handler is identical to
the first and just wastes resources.  Track the number of opens and
only register the handler when necessary.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/sound/arm/aaci.h b/sound/arm/aaci.h
index 6a4a2eebdda1..04c4568413f4 100644
--- a/sound/arm/aaci.h
+++ b/sound/arm/aaci.h
@@ -226,6 +226,8 @@ struct aaci {
         struct snd_card         *card;
         void                    __iomem *base;
         unsigned int            fifosize;
+        unsigned int            users;
+        struct mutex            irq_lock;
 
         /* AC'97 */
         struct mutex            ac97_sem;