mlxsw: switchx2: Add support for physical port names

Export to userspace the front panel name of the port, so that udev can
rename the ports accordingly. The convention suggested by switchdev
documentation is used: pX

Signed-off-by: Elad Raz <eladr@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/switchx2.c

@@ -81,6 +81,9 @@ struct mlxsw_sx_port {
 	struct mlxsw_sx_port_pcpu_stats __percpu *pcpu_stats;
 	struct mlxsw_sx *mlxsw_sx;
 	u8 local_port;
+	struct {
+		u8 module;
+	} mapping;
 };
 
 /* tx_hdr_version
@@ -257,7 +260,8 @@ mlxsw_sx_port_system_port_mapping_set(struct mlxsw_sx_port *mlxsw_sx_port)
 }
 
 static int mlxsw_sx_port_module_info_get(struct mlxsw_sx *mlxsw_sx,
-					 u8 local_port, u8 *p_width)
+					 u8 local_port, u8 *p_module,
+					 u8 *p_width)
 {
 	char pmlp_pl[MLXSW_REG_PMLP_LEN];
 	int err;
@@ -266,6 +270,7 @@ static int mlxsw_sx_port_module_info_get(struct mlxsw_sx *mlxsw_sx,
 	err = mlxsw_reg_query(mlxsw_sx->core, MLXSW_REG(pmlp), pmlp_pl);
 	if (err)
 		return err;
+	*p_module = mlxsw_reg_pmlp_module_get(pmlp_pl, 0);
 	*p_width = mlxsw_reg_pmlp_width_get(pmlp_pl);
 	return 0;
 }
@@ -383,12 +388,26 @@ mlxsw_sx_port_get_stats64(struct net_device *dev,
 	return stats;
 }
 
+static int mlxsw_sx_port_get_phys_port_name(struct net_device *dev, char *name,
+					    size_t len)
+{
+	struct mlxsw_sx_port *mlxsw_sx_port = netdev_priv(dev);
+	int err;
+
+	err = snprintf(name, len, "p%d", mlxsw_sx_port->mapping.module + 1);
+	if (err >= len)
+		return -EINVAL;
+
+	return 0;
+}
+
 static const struct net_device_ops mlxsw_sx_port_netdev_ops = {
 	.ndo_open		= mlxsw_sx_port_open,
 	.ndo_stop		= mlxsw_sx_port_stop,
 	.ndo_start_xmit		= mlxsw_sx_port_xmit,
 	.ndo_change_mtu		= mlxsw_sx_port_change_mtu,
 	.ndo_get_stats64	= mlxsw_sx_port_get_stats64,
+	.ndo_get_phys_port_name = mlxsw_sx_port_get_phys_port_name,
 };
 
 static void mlxsw_sx_port_get_drvinfo(struct net_device *dev,
@@ -957,7 +976,8 @@ mlxsw_sx_port_mac_learning_mode_set(struct mlxsw_sx_port *mlxsw_sx_port,
 	return mlxsw_reg_write(mlxsw_sx->core, MLXSW_REG(spmlr), spmlr_pl);
 }
 
-static int mlxsw_sx_port_create(struct mlxsw_sx *mlxsw_sx, u8 local_port)
+static int mlxsw_sx_port_create(struct mlxsw_sx *mlxsw_sx, u8 local_port,
+				u8 module)
 {
 	struct mlxsw_sx_port *mlxsw_sx_port;
 	struct net_device *dev;
@@ -971,6 +991,7 @@ static int mlxsw_sx_port_create(struct mlxsw_sx *mlxsw_sx, u8 local_port)
 	mlxsw_sx_port->dev = dev;
 	mlxsw_sx_port->mlxsw_sx = mlxsw_sx;
 	mlxsw_sx_port->local_port = local_port;
+	mlxsw_sx_port->mapping.module = module;
 
 	mlxsw_sx_port->pcpu_stats =
 		netdev_alloc_pcpu_stats(struct mlxsw_sx_port_pcpu_stats);
@@ -1119,7 +1140,7 @@ static void mlxsw_sx_ports_remove(struct mlxsw_sx *mlxsw_sx)
 static int mlxsw_sx_ports_create(struct mlxsw_sx *mlxsw_sx)
 {
 	size_t alloc_size;
-	u8 width;
+	u8 module, width;
 	int i;
 	int err;
 
@@ -1129,12 +1150,13 @@ static int mlxsw_sx_ports_create(struct mlxsw_sx *mlxsw_sx)
 		return -ENOMEM;
 
 	for (i = 1; i < MLXSW_PORT_MAX_PORTS; i++) {
-		err = mlxsw_sx_port_module_info_get(mlxsw_sx, i, &width);
+		err = mlxsw_sx_port_module_info_get(mlxsw_sx, i, &module,
+						    &width);
 		if (err)
 			goto err_port_module_info_get;
 		if (!width)
 			continue;
-		err = mlxsw_sx_port_create(mlxsw_sx, i);
+		err = mlxsw_sx_port_create(mlxsw_sx, i, module);
 		if (err)
 			goto err_port_create;
 	}