net: dsa: mv88e6xxx: Refactor setting of jumbo frames

Some switches support jumbo frames. Refactor this code into operations
in the ops structure.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/port.c

@@ -607,6 +607,20 @@ int mv88e6xxx_port_set_8021q_mode(struct mv88e6xxx_chip *chip, int port,
 	return 0;
 }
 
+int mv88e6165_port_jumbo_config(struct mv88e6xxx_chip *chip, int port)
+{
+	u16 reg;
+	int err;
+
+	err = mv88e6xxx_port_read(chip, port, PORT_CONTROL_2, &reg);
+	if (err)
+		return err;
+
+	reg |= PORT_CONTROL_2_JUMBO_10240;
+
+	return mv88e6xxx_port_write(chip, port, PORT_CONTROL_2, reg);
+}
+
 /* Offset 0x0f: Port Ether type */
 
 int mv88e6351_port_set_ether_type(struct mv88e6xxx_chip *chip, int port,