[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>

5 files changed, 42 insertions, 37 deletions

diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 106d428b72c9..276a21530b95 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -1800,14 +1800,15 @@ static struct backlight_properties aty128_bl_data = {
 
 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 @@ static void aty128_bl_init(struct aty128fb_par *par)
                 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);
diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 510e4ea296ed..19a71f045784 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -2199,14 +2199,15 @@ static struct backlight_properties aty_bl_data = {
 
 static void aty_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;
-        __aty_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;
+                __aty_bl_update_status(info->bl_dev);
+                up(&info->bl_dev->sem);
+        }
+
         mutex_unlock(&info->bl_mutex);
 }
 
@@ -2237,11 +2238,11 @@ static void aty_bl_init(struct atyfb_par *par)
                 0xFF * FB_BACKLIGHT_MAX / MAX_LEVEL);
         mutex_unlock(&info->bl_mutex);
 
-        up(&bd->sem);
+        down(&bd->sem);
         bd->props->brightness = aty_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);
diff --git a/drivers/video/aty/radeon_backlight.c b/drivers/video/aty/radeon_backlight.c
index 1755dddf1899..585eb7b9e636 100644
--- a/drivers/video/aty/radeon_backlight.c
+++ b/drivers/video/aty/radeon_backlight.c
@@ -195,11 +195,11 @@ void radeonfb_bl_init(struct radeonfb_info *rinfo)
                 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
         mutex_unlock(&rinfo->info->bl_mutex);
 
-        up(&bd->sem);
+        down(&bd->sem);
         bd->props->brightness = radeon_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);
diff --git a/drivers/video/nvidia/nv_backlight.c b/drivers/video/nvidia/nv_backlight.c
index 14c37c42191c..5b75ae4e9457 100644
--- a/drivers/video/nvidia/nv_backlight.c
+++ b/drivers/video/nvidia/nv_backlight.c
@@ -112,13 +112,15 @@ static struct backlight_properties nvidia_bl_data = {
 
 void nvidia_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;
-        __nvidia_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;
+                __nvidia_bl_update_status(info->bl_dev);
+                up(&info->bl_dev->sem);
+        }
+
         mutex_unlock(&info->bl_mutex);
 }
 
@@ -153,11 +155,11 @@ void nvidia_bl_init(struct nvidia_par *par)
                 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
         mutex_unlock(&info->bl_mutex);
 
-        up(&bd->sem);
+        down(&bd->sem);
         bd->props->brightness = nvidia_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);
diff --git a/drivers/video/riva/fbdev.c b/drivers/video/riva/fbdev.c
index 90363943bd57..8ddb47a56b07 100644
--- a/drivers/video/riva/fbdev.c
+++ b/drivers/video/riva/fbdev.c
@@ -354,14 +354,15 @@ static struct backlight_properties riva_bl_data = {
 
 static void riva_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;
-        __riva_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;
+                __riva_bl_update_status(info->bl_dev);
+                up(&info->bl_dev->sem);
+        }
+
         mutex_unlock(&info->bl_mutex);
 }
 
@@ -396,11 +397,11 @@ static void riva_bl_init(struct riva_par *par)
                 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
         mutex_unlock(&info->bl_mutex);
 
-        up(&bd->sem);
+        down(&bd->sem);
         bd->props->brightness = riva_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);