diff --git a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c
index cac8f085b16d..2cf7f0fc170b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c
@@ -166,16 +166,16 @@ static inline int mlx5_ptys_rate_enum_to_int(enum mlx5_ptys_rate rate)
 	}
 }
 
-static int mlx5i_get_speed_settings(u16 ib_link_width_oper, u16 ib_proto_oper)
+static u32 mlx5i_get_speed_settings(u16 ib_link_width_oper, u16 ib_proto_oper)
 {
 	int rate, width;
 
 	rate = mlx5_ptys_rate_enum_to_int(ib_proto_oper);
 	if (rate < 0)
-		return -EINVAL;
+		return SPEED_UNKNOWN;
 	width = mlx5_ptys_width_enum_to_int(ib_link_width_oper);
 	if (width < 0)
-		return -EINVAL;
+		return SPEED_UNKNOWN;
 
 	return rate * width;
 }
@@ -198,16 +198,13 @@ static int mlx5i_get_link_ksettings(struct net_device *netdev,
 	ethtool_link_ksettings_zero_link_mode(link_ksettings, advertising);
 
 	speed = mlx5i_get_speed_settings(ib_link_width_oper, ib_proto_oper);
-	if (speed < 0)
-		return -EINVAL;
+	link_ksettings->base.speed = speed;
+	link_ksettings->base.duplex = speed == SPEED_UNKNOWN ? DUPLEX_UNKNOWN : DUPLEX_FULL;
 
-	link_ksettings->base.duplex = DUPLEX_FULL;
 	link_ksettings->base.port = PORT_OTHER;
 
 	link_ksettings->base.autoneg = AUTONEG_DISABLE;
 
-	link_ksettings->base.speed = speed;
-
 	return 0;
 }