1 files changed, 35 insertions, 7 deletions

diff --git a/drivers/video/nvidia/nv_backlight.c b/drivers/video/nvidia/nv_backlight.c
index 1c1c10c699c5..5b75ae4e9457 100644
--- a/drivers/video/nvidia/nv_backlight.c
+++ b/drivers/video/nvidia/nv_backlight.c
@@ -26,9 +26,11 @@
  */
 #define MIN_LEVEL 0x158
 #define MAX_LEVEL 0x534
+#define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)
 
 static struct backlight_properties nvidia_bl_data;
 
+/* Call with fb_info->bl_mutex held */
 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
                 int level)
 {
@@ -36,9 +38,7 @@ static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
         int nlevel;
 
         /* Get and convert the value */
-        mutex_lock(&info->bl_mutex);
-        nlevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL;
-        mutex_unlock(&info->bl_mutex);
+        nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;
 
         if (nlevel < 0)
                 nlevel = 0;
@@ -50,7 +50,8 @@ static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
         return nlevel;
 }
 
-static int nvidia_bl_update_status(struct backlight_device *bd)
+/* Call with fb_info->bl_mutex held */
+static int __nvidia_bl_update_status(struct backlight_device *bd)
 {
         struct nvidia_par *par = class_get_devdata(&bd->class_dev);
         u32 tmp_pcrt, tmp_pmc, fpcontrol;
@@ -84,6 +85,19 @@ static int nvidia_bl_update_status(struct backlight_device *bd)
         return 0;
 }
 
+static int nvidia_bl_update_status(struct backlight_device *bd)
+{
+        struct nvidia_par *par = class_get_devdata(&bd->class_dev);
+        struct fb_info *info = pci_get_drvdata(par->pci_dev);
+        int ret;
+
+        mutex_lock(&info->bl_mutex);
+        ret = __nvidia_bl_update_status(bd);
+        mutex_unlock(&info->bl_mutex);
+
+        return ret;
+}
+
 static int nvidia_bl_get_brightness(struct backlight_device *bd)
 {
         return bd->props->brightness;
@@ -96,6 +110,20 @@ static struct backlight_properties nvidia_bl_data = {
         .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
 };
 
+void nvidia_bl_set_power(struct fb_info *info, int power)
+{
+        mutex_lock(&info->bl_mutex);
+
+        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);
+}
+
 void nvidia_bl_init(struct nvidia_par *par)
 {
         struct fb_info *info = pci_get_drvdata(par->pci_dev);
@@ -116,7 +144,7 @@ void nvidia_bl_init(struct nvidia_par *par)
         bd = backlight_device_register(name, par, &nvidia_bl_data);
         if (IS_ERR(bd)) {
                 info->bl_dev = NULL;
-                printk("nvidia: Backlight registration failed\n");
+                printk(KERN_WARNING "nvidia: Backlight registration failed\n");
                 goto error;
         }
 
@@ -127,11 +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);