Merge back earlier ACPI backlight material for 3.19-rc1.

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 9d75ead2a1f9..185a57d13723 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1681,6 +1681,19 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
                 printk(KERN_ERR PREFIX "Create sysfs link\n");
 }
 
+static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
+{
+        struct acpi_video_device *dev;
+        union acpi_object *levels;
+
+        mutex_lock(&video->device_list_lock);
+        list_for_each_entry(dev, &video->video_device_list, entry) {
+                if (!acpi_video_device_lcd_query_levels(dev, &levels))
+                        kfree(levels);
+        }
+        mutex_unlock(&video->device_list_lock);
+}
+
 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
 {
         struct acpi_video_device *dev;
@@ -1688,6 +1701,8 @@ static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
         if (video->backlight_registered)
                 return 0;
 
+        acpi_video_run_bcl_for_osi(video);
+
         if (!acpi_video_verify_backlight_support())
                 return 0;