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;