diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index 6769ff6c1bc0..e44a4f87303c 100644
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -98,6 +98,7 @@ extern bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 				     int x, int y,
 				     struct drm_framebuffer *old_fb);
 extern bool drm_helper_crtc_in_use(struct drm_crtc *crtc);
+extern bool drm_helper_encoder_in_use(struct drm_encoder *encoder);
 
 extern void drm_helper_connector_dpms(struct drm_connector *connector, int mode);