diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index be825802b228ca2dcde59a03ef514a95765f3999..bb78c9e16113320e88c6de7bc2bbb1a3ee320c86 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -258,15 +258,6 @@ void acpi_video_dmi_promote_vendor(void)
 }
 EXPORT_SYMBOL(acpi_video_dmi_promote_vendor);
 
-/* To be called when a driver who previously promoted the vendor
- * interface */
-void acpi_video_dmi_demote_vendor(void)
-{
-	acpi_video_caps_check();
-	acpi_video_support &= ~ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
-}
-EXPORT_SYMBOL(acpi_video_dmi_demote_vendor);
-
 /* Returns true if video.ko can do backlight switching */
 int acpi_video_backlight_support(void)
 {
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index e4da5e35e29cd8ee66f443ddd070276ea268e248..01bffd30c6c77d56a096b6cc2d2832c8d365eda0 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -248,7 +248,6 @@ extern bool wmi_has_guid(const char *guid);
 extern long acpi_video_get_capabilities(acpi_handle graphics_dev_handle);
 extern long acpi_is_video_device(acpi_handle handle);
 extern void acpi_video_dmi_promote_vendor(void);
-extern void acpi_video_dmi_demote_vendor(void);
 extern int acpi_video_backlight_support(void);
 extern int acpi_video_display_switch_support(void);
 
@@ -268,10 +267,6 @@ static inline void acpi_video_dmi_promote_vendor(void)
 {
 }
 
-static inline void acpi_video_dmi_demote_vendor(void)
-{
-}
-
 static inline int acpi_video_backlight_support(void)
 {
 	return 0;