net: dsa: mv88e6xxx: Fix support for DSA tagging for older switches.

Older chips only support DSA tagging on the CPU port. New devices
support both DSA and EDSA. The driver needs to tell the core the tag
protocol to use, and configure the switch for what is available.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/mv88e6xxx/Kconfig b/drivers/net/dsa/mv88e6xxx/Kconfig
index 490bc06..ac77737 100644
--- a/drivers/net/dsa/mv88e6xxx/Kconfig
+++ b/drivers/net/dsa/mv88e6xxx/Kconfig
@@ -2,6 +2,7 @@
 	tristate "Marvell 88E6xxx Ethernet switch fabric support"
 	depends on NET_DSA
 	select NET_DSA_TAG_EDSA
+	select NET_DSA_TAG_DSA
 	help
 	  This driver adds support for most of the Marvell 88E6xxx models of
 	  Ethernet switch chips, except 88E6060.
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 63cad6c..b315769 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2483,28 +2483,13 @@
 		PORT_CONTROL_USE_TAG | PORT_CONTROL_USE_IP |
 		PORT_CONTROL_STATE_FORWARDING;
 	if (dsa_is_cpu_port(ds, port)) {
-		if (mv88e6xxx_6095_family(chip) || mv88e6xxx_6185_family(chip))
-			reg |= PORT_CONTROL_DSA_TAG;
-		if (mv88e6xxx_6352_family(chip) ||
-		    mv88e6xxx_6351_family(chip) ||
-		    mv88e6xxx_6165_family(chip) ||
-		    mv88e6xxx_6097_family(chip) ||
-		    mv88e6xxx_6320_family(chip)) {
+		if (mv88e6xxx_has(chip, MV88E6XXX_FLAG_EDSA))
 			reg |= PORT_CONTROL_FRAME_ETHER_TYPE_DSA |
 				PORT_CONTROL_FORWARD_UNKNOWN |
 				PORT_CONTROL_FORWARD_UNKNOWN_MC;
-		}
-
-		if (mv88e6xxx_6352_family(chip) ||
-		    mv88e6xxx_6351_family(chip) ||
-		    mv88e6xxx_6165_family(chip) ||
-		    mv88e6xxx_6097_family(chip) ||
-		    mv88e6xxx_6095_family(chip) ||
-		    mv88e6xxx_6065_family(chip) ||
-		    mv88e6xxx_6185_family(chip) ||
-		    mv88e6xxx_6320_family(chip)) {
-			reg |= PORT_CONTROL_EGRESS_ADD_TAG;
-		}
+		else
+			reg |= PORT_CONTROL_DSA_TAG;
+		reg |= PORT_CONTROL_EGRESS_ADD_TAG;
 	}
 	if (dsa_is_dsa_port(ds, port)) {
 		if (mv88e6xxx_6095_family(chip) ||
@@ -2632,10 +2617,13 @@
 		/* Port Ethertype: use the Ethertype DSA Ethertype
 		 * value.
 		 */
-		ret = _mv88e6xxx_reg_write(chip, REG_PORT(port),
-					   PORT_ETH_TYPE, ETH_P_EDSA);
-		if (ret)
-			return ret;
+		if (mv88e6xxx_has(chip, MV88E6XXX_FLAG_EDSA)) {
+			ret = _mv88e6xxx_reg_write(chip, REG_PORT(port),
+						   PORT_ETH_TYPE, ETH_P_EDSA);
+			if (ret)
+				return ret;
+		}
+
 		/* Tag Remap: use an identity 802.1p prio -> switch
 		 * prio mapping.
 		 */
@@ -3926,7 +3914,12 @@
 
 static enum dsa_tag_protocol mv88e6xxx_get_tag_protocol(struct dsa_switch *ds)
 {
-	return DSA_TAG_PROTO_EDSA;
+	struct mv88e6xxx_chip *chip = ds_to_priv(ds);
+
+	if (mv88e6xxx_has(chip, MV88E6XXX_FLAG_EDSA))
+		return DSA_TAG_PROTO_EDSA;
+
+	return DSA_TAG_PROTO_DSA;
 }
 
 static const char *mv88e6xxx_drv_probe(struct device *dsa_dev,
diff --git a/drivers/net/dsa/mv88e6xxx/mv88e6xxx.h b/drivers/net/dsa/mv88e6xxx/mv88e6xxx.h
index 1f9bab5..e157d4f 100644
--- a/drivers/net/dsa/mv88e6xxx/mv88e6xxx.h
+++ b/drivers/net/dsa/mv88e6xxx/mv88e6xxx.h
@@ -386,6 +386,12 @@
 };
 
 enum mv88e6xxx_cap {
+	/* Two different tag protocols can be used by the driver. All
+	 * switches support DSA, but only later generations support
+	 * EDSA.
+	 */
+	MV88E6XXX_CAP_EDSA,
+
 	/* Energy Efficient Ethernet.
 	 */
 	MV88E6XXX_CAP_EEE,
@@ -447,6 +453,7 @@
 };
 
 /* Bitmask of capabilities */
+#define MV88E6XXX_FLAG_EDSA		BIT(MV88E6XXX_CAP_EDSA)
 #define MV88E6XXX_FLAG_EEE		BIT(MV88E6XXX_CAP_EEE)
 
 #define MV88E6XXX_FLAG_SMI_CMD		BIT(MV88E6XXX_CAP_SMI_CMD)
@@ -547,7 +554,8 @@
 	 MV88E6XXX_FLAG_VTU)
 
 #define MV88E6XXX_FLAGS_FAMILY_6320	\
-	(MV88E6XXX_FLAG_EEE |		\
+	(MV88E6XXX_FLAG_EDSA |		\
+	 MV88E6XXX_FLAG_EEE |		\
 	 MV88E6XXX_FLAG_GLOBAL2 |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_2X |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_0X |	\
@@ -564,7 +572,8 @@
 	 MV88E6XXX_FLAGS_SMI_PHY)
 
 #define MV88E6XXX_FLAGS_FAMILY_6351	\
-	(MV88E6XXX_FLAG_GLOBAL2 |	\
+	(MV88E6XXX_FLAG_EDSA |		\
+	 MV88E6XXX_FLAG_GLOBAL2 |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_2X |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_0X |	\
 	 MV88E6XXX_FLAG_G2_SWITCH_MAC |	\
@@ -579,7 +588,8 @@
 	 MV88E6XXX_FLAGS_SMI_PHY)
 
 #define MV88E6XXX_FLAGS_FAMILY_6352	\
-	(MV88E6XXX_FLAG_EEE |		\
+	(MV88E6XXX_FLAG_EDSA |		\
+	 MV88E6XXX_FLAG_EEE |		\
 	 MV88E6XXX_FLAG_GLOBAL2 |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_2X |	\
 	 MV88E6XXX_FLAG_G2_MGMT_EN_0X |	\