net: dsa: mv88e6xxx: add STU capability

Some switch models have a STU (per VLAN port state database). Add a new
capability flag to switches info, instead of checking their family.

Also if the 6165 family has an STU, it must have a VTU, so add the
MV88E6XXX_FLAG_VTU to its family flags.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/mv88e6xxx.h b/drivers/net/dsa/mv88e6xxx.h
index ca69a93..5f09a4e 100644
--- a/drivers/net/dsa/mv88e6xxx.h
+++ b/drivers/net/dsa/mv88e6xxx.h
@@ -403,6 +403,12 @@
 	 */
 	MV88E6XXX_CAP_SMI_PHY,
 
+	/* Per VLAN Spanning Tree Unit (STU).
+	 * The Port State database, if present, is accessed through VTU
+	 * operations and dedicated SID registers. See GLOBAL_VTU_SID.
+	 */
+	MV88E6XXX_CAP_STU,
+
 	/* Switch MAC/WoL/WoF register.
 	 * This requires an indirect access to set the switch MAC address
 	 * through GLOBAL2_SWITCH_MAC, otherwise GLOBAL_MAC_01, GLOBAL_MAC_23,
@@ -436,6 +442,7 @@
 #define MV88E6XXX_FLAG_PPU		BIT(MV88E6XXX_CAP_PPU)
 #define MV88E6XXX_FLAG_PPU_ACTIVE	BIT(MV88E6XXX_CAP_PPU_ACTIVE)
 #define MV88E6XXX_FLAG_SMI_PHY		BIT(MV88E6XXX_CAP_SMI_PHY)
+#define MV88E6XXX_FLAG_STU		BIT(MV88E6XXX_CAP_STU)
 #define MV88E6XXX_FLAG_SWITCH_MAC	BIT(MV88E6XXX_CAP_SWITCH_MAC_WOL_WOF)
 #define MV88E6XXX_FLAG_TEMP		BIT(MV88E6XXX_CAP_TEMP)
 #define MV88E6XXX_FLAG_TEMP_LIMIT	BIT(MV88E6XXX_CAP_TEMP_LIMIT)
@@ -451,12 +458,15 @@
 #define MV88E6XXX_FLAGS_FAMILY_6097	\
 	(MV88E6XXX_FLAG_ATU |		\
 	 MV88E6XXX_FLAG_PPU |		\
+	 MV88E6XXX_FLAG_STU |		\
 	 MV88E6XXX_FLAG_VLANTABLE |	\
 	 MV88E6XXX_FLAG_VTU)
 
 #define MV88E6XXX_FLAGS_FAMILY_6165	\
-	(MV88E6XXX_FLAG_SWITCH_MAC |	\
-	 MV88E6XXX_FLAG_TEMP)
+	(MV88E6XXX_FLAG_STU |		\
+	 MV88E6XXX_FLAG_SWITCH_MAC |	\
+	 MV88E6XXX_FLAG_TEMP |		\
+	 MV88E6XXX_FLAG_VTU)
 
 #define MV88E6XXX_FLAGS_FAMILY_6185	\
 	(MV88E6XXX_FLAG_ATU |		\
@@ -482,6 +492,7 @@
 	 MV88E6XXX_FLAG_PORTSTATE |	\
 	 MV88E6XXX_FLAG_PPU_ACTIVE |	\
 	 MV88E6XXX_FLAG_SMI_PHY |	\
+	 MV88E6XXX_FLAG_STU |		\
 	 MV88E6XXX_FLAG_SWITCH_MAC |	\
 	 MV88E6XXX_FLAG_TEMP |		\
 	 MV88E6XXX_FLAG_VLANTABLE |	\
@@ -494,6 +505,7 @@
 	 MV88E6XXX_FLAG_PORTSTATE |	\
 	 MV88E6XXX_FLAG_PPU_ACTIVE |	\
 	 MV88E6XXX_FLAG_SMI_PHY |	\
+	 MV88E6XXX_FLAG_STU |		\
 	 MV88E6XXX_FLAG_SWITCH_MAC |	\
 	 MV88E6XXX_FLAG_TEMP |		\
 	 MV88E6XXX_FLAG_TEMP_LIMIT |	\