diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 08af8d6b844b67e0653f93c5dc012706d9a13b19..b3d68964b407677148f11551dababb0d7cb71853 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -137,8 +137,10 @@ EXPORT_SYMBOL(drm_dp_link_train_channel_eq_delay);
 u8 drm_dp_link_rate_to_bw_code(int link_rate)
 {
 	switch (link_rate) {
-	case 162000:
 	default:
+		WARN(1, "unknown DP link rate %d, using %x\n", link_rate,
+		     DP_LINK_BW_1_62);
+	case 162000:
 		return DP_LINK_BW_1_62;
 	case 270000:
 		return DP_LINK_BW_2_7;
@@ -151,8 +153,9 @@ EXPORT_SYMBOL(drm_dp_link_rate_to_bw_code);
 int drm_dp_bw_code_to_link_rate(u8 link_bw)
 {
 	switch (link_bw) {
-	case DP_LINK_BW_1_62:
 	default:
+		WARN(1, "unknown DP link BW code %x, using 162000\n", link_bw);
+	case DP_LINK_BW_1_62:
 		return 162000;
 	case DP_LINK_BW_2_7:
 		return 270000;