net: dsa: setup and teardown default CPU port

The dsa_dst_parse function called just before dsa_dst_apply does not
parse the tree but does only one thing: it assigns the default CPU port
to dst->cpu_dp and to each user ports.

This patch simplifies this by calling a dsa_tree_setup_default_cpu
function at the beginning of dsa_dst_apply directly.

A dsa_port_is_user helper is added for convenience.

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

1 files changed, 68 insertions, 85 deletions

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 283104e5ca6a..0a63a2119cd0 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -112,6 +112,11 @@ static bool dsa_port_is_cpu(struct dsa_port *port)
         return port->type == DSA_PORT_TYPE_CPU;
 }
 
+static bool dsa_port_is_user(struct dsa_port *dp)
+{
+        return dp->type == DSA_PORT_TYPE_USER;
+}
+
 static bool dsa_ds_find_port_dn(struct dsa_switch *ds,
                                 struct device_node *port)
 {
@@ -218,6 +223,64 @@ static int dsa_dst_complete(struct dsa_switch_tree *dst)
         return 0;
 }
 
+static struct dsa_port *dsa_tree_find_first_cpu(struct dsa_switch_tree *dst)
+{
+        struct dsa_switch *ds;
+        struct dsa_port *dp;
+        int device, port;
+
+        for (device = 0; device < DSA_MAX_SWITCHES; device++) {
+                ds = dst->ds[device];
+                if (!ds)
+                        continue;
+
+                for (port = 0; port < ds->num_ports; port++) {
+                        dp = &ds->ports[port];
+
+                        if (dsa_port_is_cpu(dp))
+                                return dp;
+                }
+        }
+
+        return NULL;
+}
+
+static int dsa_tree_setup_default_cpu(struct dsa_switch_tree *dst)
+{
+        struct dsa_switch *ds;
+        struct dsa_port *dp;
+        int device, port;
+
+        /* DSA currently only supports a single CPU port */
+        dst->cpu_dp = dsa_tree_find_first_cpu(dst);
+        if (!dst->cpu_dp) {
+                pr_warn("Tree has no master device\n");
+                return -EINVAL;
+        }
+
+        /* Assign the default CPU port to all ports of the fabric */
+        for (device = 0; device < DSA_MAX_SWITCHES; device++) {
+                ds = dst->ds[device];
+                if (!ds)
+                        continue;
+
+                for (port = 0; port < ds->num_ports; port++) {
+                        dp = &ds->ports[port];
+
+                        if (dsa_port_is_user(dp))
+                                dp->cpu_dp = dst->cpu_dp;
+                }
+        }
+
+        return 0;
+}
+
+static void dsa_tree_teardown_default_cpu(struct dsa_switch_tree *dst)
+{
+        /* DSA currently only supports a single CPU port */
+        dst->cpu_dp = NULL;
+}
+
 static int dsa_dsa_port_apply(struct dsa_port *port)
 {
         struct dsa_switch *ds = port->ds;
@@ -412,6 +475,10 @@ static int dsa_dst_apply(struct dsa_switch_tree *dst)
         u32 index;
         int err;
 
+        err = dsa_tree_setup_default_cpu(dst);
+        if (err)
+                return err;
+
         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
                 ds = dst->ds[index];
                 if (!ds)
@@ -464,7 +531,7 @@ static void dsa_dst_unapply(struct dsa_switch_tree *dst)
                 dsa_ds_unapply(dst, ds);
         }
 
-        dst->cpu_dp = NULL;
+        dsa_tree_teardown_default_cpu(dst);
 
         pr_info("DSA: tree %d unapplied\n", dst->index);
         dst->applied = false;
@@ -532,86 +599,6 @@ static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master)
         return 0;
 }
 
-static int dsa_cpu_parse(struct dsa_port *port, u32 index,
-                         struct dsa_switch_tree *dst,
-                         struct dsa_switch *ds)
-{
-        if (!dst->cpu_dp)
-                dst->cpu_dp = port;
-
-        return 0;
-}
-
-static int dsa_ds_parse(struct dsa_switch_tree *dst, struct dsa_switch *ds)
-{
-        struct dsa_port *port;
-        u32 index;
-        int err;
-
-        for (index = 0; index < ds->num_ports; index++) {
-                port = &ds->ports[index];
-                if (!dsa_port_is_valid(port) ||
-                    dsa_port_is_dsa(port))
-                        continue;
-
-                if (dsa_port_is_cpu(port)) {
-                        err = dsa_cpu_parse(port, index, dst, ds);
-                        if (err)
-                                return err;
-                }
-
-        }
-
-        pr_info("DSA: switch %d %d parsed\n", dst->index, ds->index);
-
-        return 0;
-}
-
-static int dsa_dst_parse(struct dsa_switch_tree *dst)
-{
-        struct dsa_switch *ds;
-        struct dsa_port *dp;
-        u32 index;
-        int port;
-        int err;
-
-        for (index = 0; index < DSA_MAX_SWITCHES; index++) {
-                ds = dst->ds[index];
-                if (!ds)
-                        continue;
-
-                err = dsa_ds_parse(dst, ds);
-                if (err)
-                        return err;
-        }
-
-        if (!dst->cpu_dp) {
-                pr_warn("Tree has no master device\n");
-                return -EINVAL;
-        }
-
-        /* Assign the default CPU port to all ports of the fabric */
-        for (index = 0; index < DSA_MAX_SWITCHES; index++) {
-                ds = dst->ds[index];
-                if (!ds)
-                        continue;
-
-                for (port = 0; port < ds->num_ports; port++) {
-                        dp = &ds->ports[port];
-                        if (!dsa_port_is_valid(dp) ||
-                            dsa_port_is_dsa(dp) ||
-                            dsa_port_is_cpu(dp))
-                                continue;
-
-                        dp->cpu_dp = dst->cpu_dp;
-                }
-        }
-
-        pr_info("DSA: tree %d parsed\n", dst->index);
-
-        return 0;
-}
-
 static int dsa_port_parse_of(struct dsa_port *dp, struct device_node *dn)
 {
         struct device_node *ethernet = of_parse_phandle(dn, "ethernet", 0);
@@ -810,10 +797,6 @@ static int _dsa_register_switch(struct dsa_switch *ds)
                 return -EINVAL;
         }
 
-        err = dsa_dst_parse(dst);
-        if (err)
-                goto out_del_dst;
-
         err = dsa_dst_apply(dst);
         if (err) {
                 dsa_dst_unapply(dst);