From 28ee086d5b36aab2931f6740e409bb0fb6c65e5f Mon Sep 17 00:00:00 2001
From: Richard Purdie <rpurdie@rpsys.net>
Date: Thu, 8 Feb 2007 22:25:09 +0000
Subject: backlight: Fix external uses of backlight internal semaphore

backlight_device->sem has a very specific use as documented in the
header file. The external users of this are using it for a different
reason, to serialise access to the update_status() method.

backlight users were supposed to implement their own internal
serialisation of update_status() if needed but everyone is doing
things differently and incorrectly. Therefore add a global mutex to
take care of serialisation for everyone, once and for all.

Locking for get_brightness remains optional since most users don't
need it.

Also update the lcd class in a similar way.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
---
 drivers/macintosh/via-pmu-backlight.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

(limited to 'drivers/macintosh')

diff --git a/drivers/macintosh/via-pmu-backlight.c b/drivers/macintosh/via-pmu-backlight.c
index db8bcc35bc03..7ba2042b2dd0 100644
--- a/drivers/macintosh/via-pmu-backlight.c
+++ b/drivers/macintosh/via-pmu-backlight.c
@@ -166,11 +166,9 @@ void __init pmu_backlight_init()
 				pmu_backlight_data.max_brightness / 15);
 	}
 
-	down(&bd->sem);
 	bd->props->brightness = level;
 	bd->props->power = FB_BLANK_UNBLANK;
-	bd->props->update_status(bd);
-	up(&bd->sem);
+	backlight_update_status(bd);
 
 	mutex_lock(&pmac_backlight_mutex);
 	if (!pmac_backlight)
-- 
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