[PATCH] backlight last round of fixes

Fix some more problems (inverted use of semaphores in some places).  He
also moved my checks into within the protected section which is better.

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 106d428..276a215 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -1800,14 +1800,15 @@
 
 static void aty128_bl_set_power(struct fb_info *info, int power)
 {
-	if (info->bl_dev == NULL)
-		return;
-
 	mutex_lock(&info->bl_mutex);
-	up(&info->bl_dev->sem);
-	info->bl_dev->props->power = power;
-	__aty128_bl_update_status(info->bl_dev);
-	down(&info->bl_dev->sem);
+
+	if (info->bl_dev) {
+		down(&info->bl_dev->sem);
+		info->bl_dev->props->power = power;
+		__aty128_bl_update_status(info->bl_dev);
+		up(&info->bl_dev->sem);
+	}
+
 	mutex_unlock(&info->bl_mutex);
 }
 
@@ -1842,11 +1843,11 @@
 		219 * FB_BACKLIGHT_MAX / MAX_LEVEL);
 	mutex_unlock(&info->bl_mutex);
 
-	up(&bd->sem);
+	down(&bd->sem);
 	bd->props->brightness = aty128_bl_data.max_brightness;
 	bd->props->power = FB_BLANK_UNBLANK;
 	bd->props->update_status(bd);
-	down(&bd->sem);
+	up(&bd->sem);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
 	mutex_lock(&pmac_backlight_mutex);