diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index dbb425717f5ed4971ecdfc4b01f3bdfef555aac6..dfe6b44baf635701e155809b5b9304e55c63faae 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -3128,6 +3128,10 @@ mlxsw_sp_port_set_link_ksettings(struct net_device *dev,
 	ops->reg_ptys_eth_unpack(mlxsw_sp, ptys_pl, &eth_proto_cap, NULL, NULL);
 
 	autoneg = cmd->base.autoneg == AUTONEG_ENABLE;
+	if (!autoneg && cmd->base.speed == SPEED_56000) {
+		netdev_err(dev, "56G not supported with autoneg off\n");
+		return -EINVAL;
+	}
 	eth_proto_new = autoneg ?
 		ops->to_ptys_advert_link(mlxsw_sp, cmd) :
 		ops->to_ptys_speed(mlxsw_sp, cmd->base.speed);