diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 2740a0ef3f49..987fbb2ef911 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1245,23 +1245,29 @@ intel_attached_encoder(struct drm_connector *connector)
 	return to_intel_connector(connector)->encoder;
 }
 
+static inline bool intel_encoder_is_dig_port(struct intel_encoder *encoder)
+{
+	switch (encoder->type) {
+	case INTEL_OUTPUT_DDI:
+	case INTEL_OUTPUT_DP:
+	case INTEL_OUTPUT_EDP:
+	case INTEL_OUTPUT_HDMI:
+		return true;
+	default:
+		return false;
+	}
+}
+
 static inline struct intel_digital_port *
 enc_to_dig_port(struct drm_encoder *encoder)
 {
 	struct intel_encoder *intel_encoder = to_intel_encoder(encoder);
 
-	switch (intel_encoder->type) {
-	case INTEL_OUTPUT_DDI:
-		WARN_ON(!HAS_DDI(to_i915(encoder->dev)));
-		/* fall through */
-	case INTEL_OUTPUT_DP:
-	case INTEL_OUTPUT_EDP:
-	case INTEL_OUTPUT_HDMI:
+	if (intel_encoder_is_dig_port(intel_encoder))
 		return container_of(encoder, struct intel_digital_port,
 				    base.base);
-	default:
+	else
 		return NULL;
-	}
 }
 
 static inline struct intel_dp_mst_encoder *