diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
index f9776ca85de3..2b1423a43437 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -1707,6 +1707,39 @@ static void sanitize_aux_ch(struct intel_bios_encoder_data *devdata,
 	child->aux_channel = 0;
 }
 
+static u8 dvo_port_type(u8 dvo_port)
+{
+	switch (dvo_port) {
+	case DVO_PORT_HDMIA:
+	case DVO_PORT_HDMIB:
+	case DVO_PORT_HDMIC:
+	case DVO_PORT_HDMID:
+	case DVO_PORT_HDMIE:
+	case DVO_PORT_HDMIF:
+	case DVO_PORT_HDMIG:
+	case DVO_PORT_HDMIH:
+	case DVO_PORT_HDMII:
+		return DVO_PORT_HDMIA;
+	case DVO_PORT_DPA:
+	case DVO_PORT_DPB:
+	case DVO_PORT_DPC:
+	case DVO_PORT_DPD:
+	case DVO_PORT_DPE:
+	case DVO_PORT_DPF:
+	case DVO_PORT_DPG:
+	case DVO_PORT_DPH:
+	case DVO_PORT_DPI:
+		return DVO_PORT_DPA;
+	case DVO_PORT_MIPIA:
+	case DVO_PORT_MIPIB:
+	case DVO_PORT_MIPIC:
+	case DVO_PORT_MIPID:
+		return DVO_PORT_MIPIA;
+	default:
+		return dvo_port;
+	}
+}
+
 static enum port __dvo_port_to_port(int n_ports, int n_dvo,
 				    const int port_mapping[][3], u8 dvo_port)
 {
@@ -2623,8 +2656,25 @@ bool intel_bios_is_port_edp(struct drm_i915_private *i915, enum port port)
 	return false;
 }
 
-static bool child_dev_is_dp_dual_mode(const struct child_device_config *child,
-				      enum port port)
+static bool child_dev_is_dp_dual_mode(const struct child_device_config *child)
+{
+	if ((child->device_type & DEVICE_TYPE_DP_DUAL_MODE_BITS) !=
+	    (DEVICE_TYPE_DP_DUAL_MODE & DEVICE_TYPE_DP_DUAL_MODE_BITS))
+		return false;
+
+	if (dvo_port_type(child->dvo_port) == DVO_PORT_DPA)
+		return true;
+
+	/* Only accept a HDMI dvo_port as DP++ if it has an AUX channel */
+	if (dvo_port_type(child->dvo_port) == DVO_PORT_HDMIA &&
+	    child->aux_channel != 0)
+		return true;
+
+	return false;
+}
+
+bool intel_bios_is_port_dp_dual_mode(struct drm_i915_private *i915,
+				     enum port port)
 {
 	static const struct {
 		u16 dp, hdmi;
@@ -2639,32 +2689,23 @@ static bool child_dev_is_dp_dual_mode(const struct child_device_config *child,
 		[PORT_E] = { DVO_PORT_DPE, DVO_PORT_HDMIE, },
 		[PORT_F] = { DVO_PORT_DPF, DVO_PORT_HDMIF, },
 	};
+	const struct intel_bios_encoder_data *devdata;
+
+	if (HAS_DDI(i915)) {
+		const struct intel_bios_encoder_data *devdata;
+
+		devdata = intel_bios_encoder_data_lookup(i915, port);
+
+		return devdata && child_dev_is_dp_dual_mode(&devdata->child);
+	}
 
 	if (port == PORT_A || port >= ARRAY_SIZE(port_mapping))
 		return false;
 
-	if ((child->device_type & DEVICE_TYPE_DP_DUAL_MODE_BITS) !=
-	    (DEVICE_TYPE_DP_DUAL_MODE & DEVICE_TYPE_DP_DUAL_MODE_BITS))
-		return false;
-
-	if (child->dvo_port == port_mapping[port].dp)
-		return true;
-
-	/* Only accept a HDMI dvo_port as DP++ if it has an AUX channel */
-	if (child->dvo_port == port_mapping[port].hdmi &&
-	    child->aux_channel != 0)
-		return true;
-
-	return false;
-}
-
-bool intel_bios_is_port_dp_dual_mode(struct drm_i915_private *i915,
-				     enum port port)
-{
-	const struct intel_bios_encoder_data *devdata;
-
 	list_for_each_entry(devdata, &i915->vbt.display_devices, node) {
-		if (child_dev_is_dp_dual_mode(&devdata->child, port))
+		if ((devdata->child.dvo_port == port_mapping[port].dp ||
+		     devdata->child.dvo_port == port_mapping[port].hdmi) &&
+		    child_dev_is_dp_dual_mode(&devdata->child))
 			return true;
 	}