net: dsa: pass bridge device when a port leaves

Upon reception of the NETDEV_CHANGEUPPER, a leaving port is already
unbridged, so reflect this by assigning the port's bridge_dev pointer to
NULL before calling the port_bridge_leave DSA driver operation.

Now that the bridge_dev pointer is exposed to the drivers, reflecting
the current state of the DSA switch fabric is necessary for the drivers
to adjust their port based VLANs correctly.

Pass the bridge device pointer to the port_bridge_leave operation so
that drivers have all information to re-program their chips properly,
and do not need to cache it anymore.

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

drivers/net/dsa/b53/b53_common.c

@@ -1354,7 +1354,7 @@ int b53_br_join(struct dsa_switch *ds, int port, struct net_device *bridge)
 }
 EXPORT_SYMBOL(b53_br_join);
 
-void b53_br_leave(struct dsa_switch *ds, int port)
+void b53_br_leave(struct dsa_switch *ds, int port, struct net_device *br)
 {
 	struct b53_device *dev = ds->priv;
 	struct net_device *bridge = dev->ports[port].bridge_dev;

drivers/net/dsa/b53/b53_priv.h

@@ -382,7 +382,7 @@ void b53_get_strings(struct dsa_switch *ds, int port, uint8_t *data);
 void b53_get_ethtool_stats(struct dsa_switch *ds, int port, uint64_t *data);
 int b53_get_sset_count(struct dsa_switch *ds);
 int b53_br_join(struct dsa_switch *ds, int port, struct net_device *bridge);
-void b53_br_leave(struct dsa_switch *ds, int port);
+void b53_br_leave(struct dsa_switch *ds, int port, struct net_device *bridge);
 void b53_br_set_stp_state(struct dsa_switch *ds, int port, u8 state);
 void b53_br_fast_age(struct dsa_switch *ds, int port);
 int b53_vlan_filtering(struct dsa_switch *ds, int port, bool vlan_filtering);