net: dsa: define port types

Introduce an enumerated type for ports, which will be way more explicit
to identify a port type instead of digging into switch port masks.

A port can be of type CPU, DSA, user, or unused by default. This is a
static parsed information that cannot be changed at runtime.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -180,6 +180,13 @@ struct dsa_port {
 	struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev,
 			       struct packet_type *pt);
 
+	enum {
+		DSA_PORT_TYPE_UNUSED = 0,
+		DSA_PORT_TYPE_CPU,
+		DSA_PORT_TYPE_DSA,
+		DSA_PORT_TYPE_USER,
+	} type;
+
 	struct dsa_switch	*ds;
 	unsigned int		index;
 	const char		*name;

net/dsa/dsa2.c

@@ -185,6 +185,7 @@ static int dsa_ds_complete(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 			return err;
 
 		ds->dsa_port_mask |= BIT(index);
+		port->type = DSA_PORT_TYPE_DSA;
 	}
 
 	return 0;
@@ -504,6 +505,7 @@ static int dsa_cpu_parse(struct dsa_port *port, u32 index,
 	 * net/dsa/dsa.c::dsa_switch_setup_one does.
 	 */
 	ds->cpu_port_mask |= BIT(index);
+	port->type = DSA_PORT_TYPE_CPU;
 
 	tag_protocol = ds->ops->get_tag_protocol(ds);
 	tag_ops = dsa_resolve_tag_protocol(tag_protocol);
@@ -543,6 +545,7 @@ static int dsa_ds_parse(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 			 * net/dsa/dsa.c::dsa_switch_setup_one does.
 			 */
 			ds->enabled_port_mask |= BIT(index);
+			port->type = DSA_PORT_TYPE_USER;
 		}
 
 	}

net/dsa/legacy.c

@@ -101,6 +101,7 @@ static int dsa_switch_setup_one(struct dsa_switch *ds,
 	struct dsa_chip_data *cd = ds->cd;
 	bool valid_name_found = false;
 	int index = ds->index;
+	struct dsa_port *dp;
 	int i, ret;
 
 	/*
@@ -109,6 +110,8 @@ static int dsa_switch_setup_one(struct dsa_switch *ds,
 	for (i = 0; i < ds->num_ports; i++) {
 		char *name;
 
+		dp = &ds->ports[i];
+
 		name = cd->port_names[i];
 		if (name == NULL)
 			continue;
@@ -122,10 +125,13 @@ static int dsa_switch_setup_one(struct dsa_switch *ds,
 			dst->cpu_dp = &ds->ports[i];
 			dst->cpu_dp->master = master;
 			ds->cpu_port_mask |= 1 << i;
+			dp->type = DSA_PORT_TYPE_CPU;
 		} else if (!strcmp(name, "dsa")) {
 			ds->dsa_port_mask |= 1 << i;
+			dp->type = DSA_PORT_TYPE_DSA;
 		} else {
 			ds->enabled_port_mask |= 1 << i;
+			dp->type = DSA_PORT_TYPE_USER;
 		}
 		valid_name_found = true;
 	}