diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 3134f50..67c251f 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -290,6 +290,48 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
 EXPORT_SYMBOL(drm_atomic_get_crtc_state);
 
 /**
+ * drm_atomic_set_mode_for_crtc - set mode for CRTC
+ * @state: the CRTC whose incoming state to update
+ * @mode: kernel-internal mode to use for the CRTC, or NULL to disable
+ *
+ * Set a mode (originating from the kernel) on the desired CRTC state, and
+ * update the CRTC state's enable and mode_changed parameters as necessary.
+ * If disabling, it will also set active to false.
+ */
+int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
+				 struct drm_display_mode *mode)
+{
+	/* Early return for no change. */
+	if (!mode && !state->enable)
+		return 0;
+	if (mode && state->enable &&
+	    memcmp(&state->mode, mode, sizeof(*mode)) == 0)
+		return 0;
+
+	state->mode_changed = true;
+
+	if (mode) {
+		drm_mode_copy(&state->mode, mode);
+		state->enable = true;
+	} else {
+		memset(&state->mode, 0, sizeof(state->mode));
+		state->enable = false;
+		state->active = false;
+	}
+
+	if (state->enable)
+		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
+				 mode->name, state);
+	else
+		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
+				 state);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_atomic_set_mode_for_crtc);
+
+
+/**
  * drm_atomic_crtc_set_property - set property on CRTC
  * @crtc: the drm CRTC to set a property on
  * @state: the state object to update with the new property value
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index a64bacd..70ce243 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -369,20 +369,6 @@ drm_atomic_helper_check_modeset(struct drm_device *dev,
 	struct drm_connector_state *connector_state;
 	int i, ret;
 
-	for_each_crtc_in_state(state, crtc, crtc_state, i) {
-		if (!drm_mode_equal(&crtc->state->mode, &crtc_state->mode)) {
-			DRM_DEBUG_ATOMIC("[CRTC:%d] mode changed\n",
-					 crtc->base.id);
-			crtc_state->mode_changed = true;
-		}
-
-		if (crtc->state->enable != crtc_state->enable) {
-			DRM_DEBUG_ATOMIC("[CRTC:%d] enable changed\n",
-					 crtc->base.id);
-			crtc_state->mode_changed = true;
-		}
-	}
-
 	for_each_connector_in_state(state, connector, connector_state, i) {
 		/*
 		 * This only sets crtc->mode_changed for routing changes,
@@ -1607,8 +1593,9 @@ retry:
 		WARN_ON(set->fb);
 		WARN_ON(set->num_connectors);
 
-		crtc_state->enable = false;
-		crtc_state->active = false;
+		ret = drm_atomic_set_mode_for_crtc(crtc_state, NULL);
+		if (ret != 0)
+			goto fail;
 
 		ret = drm_atomic_set_crtc_for_plane(primary_state, NULL);
 		if (ret != 0)
@@ -1622,9 +1609,10 @@ retry:
 	WARN_ON(!set->fb);
 	WARN_ON(!set->num_connectors);
 
-	crtc_state->enable = true;
+	ret = drm_atomic_set_mode_for_crtc(crtc_state, set->mode);
+	if (ret != 0)
+		goto fail;
 	crtc_state->active = true;
-	drm_mode_copy(&crtc_state->mode, set->mode);
 
 	ret = drm_atomic_set_crtc_for_plane(primary_state, crtc);
 	if (ret != 0)
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 9297a61..cc77a4f 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -937,10 +937,10 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mod
 			crtc_state->crtc = crtc;
 	}
 
-	crtc_state->enable = true;
 	crtc_state->planes_changed = true;
-	crtc_state->mode_changed = true;
-	drm_mode_copy(&crtc_state->mode, mode);
+	ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
+	if (ret)
+		goto out;
 	drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
 
 	if (crtc_funcs->atomic_check) {
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 240092a..7e31972 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9896,7 +9896,9 @@ retry:
 	if (ret)
 		goto fail;
 
-	drm_mode_copy(&crtc_state->base.mode, mode);
+	ret = drm_atomic_set_mode_for_crtc(&crtc_state->base, mode);
+	if (ret)
+		goto fail;
 
 	if (intel_set_mode(crtc, state)) {
 		DRM_DEBUG_KMS("failed to set mode on load-detect pipe\n");
@@ -12494,8 +12496,11 @@ void intel_crtc_restore_mode(struct drm_crtc *crtc)
 
 		crtc_state->base.enable = intel_crtc->new_enabled;
 
-		if (&intel_crtc->base == crtc)
-			drm_mode_copy(&crtc_state->base.mode, &crtc->mode);
+		if (&intel_crtc->base == crtc) {
+			ret = drm_atomic_set_mode_for_crtc(&crtc_state->base,
+							   &crtc->mode);
+			WARN_ON(ret);
+		}
 	}
 
 	intel_modeset_setup_plane_state(state, crtc, &crtc->mode,
@@ -12633,8 +12638,9 @@ intel_modeset_stage_output_state(struct drm_device *dev,
 	if (IS_ERR(crtc_state))
 		return PTR_ERR(crtc_state);
 
-	if (set->mode)
-		drm_mode_copy(&crtc_state->mode, set->mode);
+	ret = drm_atomic_set_mode_for_crtc(crtc_state, set->mode);
+	if (ret)
+		return ret;
 
 	if (set->num_connectors)
 		crtc_state->active = true;
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index e89db0c..55f4604 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -110,6 +110,12 @@ drm_atomic_get_existing_connector_state(struct drm_atomic_state *state,
 }
 
 int __must_check
+drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
+			     struct drm_display_mode *mode);
+int __must_check
+drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
+				  struct drm_property_blob *blob);
+int __must_check
 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
 			      struct drm_crtc *crtc);
 void drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
