diff --git a/drivers/gpu/drm/drm_gem_atomic_helper.c b/drivers/gpu/drm/drm_gem_atomic_helper.c
index 3bb6bfd560d3..dd9efa7e3216 100644
--- a/drivers/gpu/drm/drm_gem_atomic_helper.c
+++ b/drivers/gpu/drm/drm_gem_atomic_helper.c
@@ -319,26 +319,6 @@ void drm_gem_destroy_shadow_plane_state(struct drm_plane *plane,
 }
 EXPORT_SYMBOL(drm_gem_destroy_shadow_plane_state);
 
-/**
- * __drm_gem_reset_shadow_plane - resets a shadow-buffered plane
- * @plane: the plane
- * @shadow_plane_state: the shadow-buffered plane state
- *
- * This function resets state for shadow-buffered planes. Helpful
- * for drivers that subclass struct drm_shadow_plane_state.
- */
-void __drm_gem_reset_shadow_plane(struct drm_plane *plane,
-				  struct drm_shadow_plane_state *shadow_plane_state)
-{
-	if (shadow_plane_state) {
-		__drm_atomic_helper_plane_reset(plane, &shadow_plane_state->base);
-		drm_format_conv_state_init(&shadow_plane_state->fmtcnv_state);
-	} else {
-		__drm_atomic_helper_plane_reset(plane, NULL);
-	}
-}
-EXPORT_SYMBOL(__drm_gem_reset_shadow_plane);
-
 /**
  * drm_gem_begin_shadow_fb_access - prepares shadow framebuffers for CPU access
  * @plane: the plane
diff --git a/include/drm/drm_gem_atomic_helper.h b/include/drm/drm_gem_atomic_helper.h
index 2deb0cd9ebbe..d41877f77b77 100644
--- a/include/drm/drm_gem_atomic_helper.h
+++ b/include/drm/drm_gem_atomic_helper.h
@@ -91,8 +91,6 @@ to_drm_shadow_plane_state(struct drm_plane_state *state)
 void __drm_gem_duplicate_shadow_plane_state(struct drm_plane *plane,
 					    struct drm_shadow_plane_state *new_shadow_plane_state);
 void __drm_gem_destroy_shadow_plane_state(struct drm_shadow_plane_state *shadow_plane_state);
-void __drm_gem_reset_shadow_plane(struct drm_plane *plane,
-				  struct drm_shadow_plane_state *shadow_plane_state);
 
 void __drm_gem_shadow_plane_state_init(struct drm_plane *plane,
 				       struct drm_shadow_plane_state *shadow_plane_state);