net: dsa: add cross-chip bridging operations

Introduce crosschip_bridge_{join,leave} operations in the dsa_switch_ops
structure, which can be used by switches supporting interconnection.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -456,6 +456,14 @@ struct dsa_switch_ops {
 				   bool ingress);
 	void	(*port_mirror_del)(struct dsa_switch *ds, int port,
 				   struct dsa_mall_mirror_tc_entry *mirror);
+
+	/*
+	 * Cross-chip operations
+	 */
+	int	(*crosschip_bridge_join)(struct dsa_switch *ds, int sw_index,
+					 int port, struct net_device *br);
+	void	(*crosschip_bridge_leave)(struct dsa_switch *ds, int sw_index,
+					  int port, struct net_device *br);
 };
 
 struct dsa_switch_driver {

net/dsa/switch.c

@@ -20,9 +20,9 @@ static int dsa_switch_bridge_join(struct dsa_switch *ds,
 	if (ds->index == info->sw_index && ds->ops->port_bridge_join)
 		return ds->ops->port_bridge_join(ds, info->port, info->br);
 
-	if (ds->index != info->sw_index)
-		dev_dbg(ds->dev, "crosschip DSA port %d.%d bridged to %s\n",
-			info->sw_index, info->port, netdev_name(info->br));
+	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
+		return ds->ops->crosschip_bridge_join(ds, info->sw_index,
+						      info->port, info->br);
 
 	return 0;
 }
@@ -33,9 +33,9 @@ static int dsa_switch_bridge_leave(struct dsa_switch *ds,
 	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
 		ds->ops->port_bridge_leave(ds, info->port, info->br);
 
-	if (ds->index != info->sw_index)
-		dev_dbg(ds->dev, "crosschip DSA port %d.%d unbridged from %s\n",
-			info->sw_index, info->port, netdev_name(info->br));
+	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
+		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
+						info->br);
 
 	return 0;
 }