mlxsw: spectrum: Handle PORT_PRE_BRIDGE_FLAGS

In preparation for getting rid of switchdev_port_attr_get(), have mlxsw
check for the bridge flags being set through switchdev_port_attr_set()
when the SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS attribute identifier is
used.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c

@@ -595,6 +595,17 @@ mlxsw_sp_bridge_port_learning_set(struct mlxsw_sp_port *mlxsw_sp_port,
 	return err;
 }
 
+static int mlxsw_sp_port_attr_br_pre_flags_set(struct mlxsw_sp_port
+					       *mlxsw_sp_port,
+					       struct switchdev_trans *trans,
+					       unsigned long brport_flags)
+{
+	if (brport_flags & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD))
+		return -EINVAL;
+
+	return 0;
+}
+
 static int mlxsw_sp_port_attr_br_flags_set(struct mlxsw_sp_port *mlxsw_sp_port,
 					   struct switchdev_trans *trans,
 					   struct net_device *orig_dev,
@@ -841,6 +852,11 @@ static int mlxsw_sp_port_attr_set(struct net_device *dev,
 						       attr->orig_dev,
 						       attr->u.stp_state);
 		break;
+	case SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS:
+		err = mlxsw_sp_port_attr_br_pre_flags_set(mlxsw_sp_port,
+							  trans,
+							  attr->u.brport_flags);
+		break;
 	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS:
 		err = mlxsw_sp_port_attr_br_flags_set(mlxsw_sp_port, trans,
 						      attr->orig_dev,