net: dsa: make "label" property optional for dsa2

In the new DTS bindings for DSA (dsa2), the "ethernet" and "link"
phandles are respectively mandatory and exclusive to CPU port and DSA
link device tree nodes.

Simplify dsa2.c a bit by checking the presence of such phandle instead
of checking the redundant "label" property.

Then the Linux philosophy for Ethernet switch ports is to expose them to
userspace as standard NICs by default. Thus use the standard enumerated
"eth%d" device name if no "label" property is provided for a user port.
This allows to save DTS files from subjective net device names.

If one wants to rename an interface, udev rules can be used as usual.

Of course the current behavior is unchanged, and the optional "label"
property for user ports has precedence over the enumerated name.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 20 deletions

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index bad119cee2a3..9526bdf2a34a 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -81,30 +81,12 @@ static void dsa_dst_del_ds(struct dsa_switch_tree *dst,
 
 static bool dsa_port_is_dsa(struct device_node *port)
 {
-	const char *name;
-
-	name = of_get_property(port, "label", NULL);
-	if (!name)
-		return false;
-
-	if (!strcmp(name, "dsa"))
-		return true;
-
-	return false;
+	return !!of_parse_phandle(port, "link", 0);
 }
 
 static bool dsa_port_is_cpu(struct device_node *port)
 {
-	const char *name;
-
-	name = of_get_property(port, "label", NULL);
-	if (!name)
-		return false;
-
-	if (!strcmp(name, "cpu"))
-		return true;
-
-	return false;
+	return !!of_parse_phandle(port, "ethernet", 0);
 }
 
 static bool dsa_ds_find_port(struct dsa_switch *ds,
@@ -268,6 +250,8 @@ static int dsa_user_port_apply(struct device_node *port, u32 index,
 	int err;
 
 	name = of_get_property(port, "label", NULL);
+	if (!name)
+		name = "eth%d";
 
 	err = dsa_slave_create(ds, ds->dev, index, name);
 	if (err) {