diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 1bec8de96412..77a9d67a02d1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5177,7 +5177,7 @@ static enum intel_display_power_domain port_to_power_domain(enum port port)
 	case PORT_E:
 		return POWER_DOMAIN_PORT_DDI_E_LANES;
 	default:
-		WARN_ON_ONCE(1);
+		MISSING_CASE(port);
 		return POWER_DOMAIN_PORT_OTHER;
 	}
 }
@@ -5197,7 +5197,7 @@ static enum intel_display_power_domain port_to_aux_power_domain(enum port port)
 		/* FIXME: Check VBT for actual wiring of PORT E */
 		return POWER_DOMAIN_AUX_D;
 	default:
-		WARN_ON_ONCE(1);
+		MISSING_CASE(port);
 		return POWER_DOMAIN_AUX_A;
 	}
 }
@@ -5258,7 +5258,7 @@ intel_display_port_aux_power_domain(struct intel_encoder *intel_encoder)
 		intel_dig_port = enc_to_mst(&intel_encoder->base)->primary;
 		return port_to_aux_power_domain(intel_dig_port->port);
 	default:
-		WARN_ON_ONCE(1);
+		MISSING_CASE(intel_encoder->type);
 		return POWER_DOMAIN_AUX_A;
 	}
 }