net: dsa: microchip: set the correct number of ports

The number of ports is incorrectly set to the maximum available for a DSA
switch. Even if the extra ports are not used, this causes some functions
to be called later, like port_disable() and port_stp_state_set(). If the
driver doesn't check the port index, it will end up modifying unknown
registers.

Fixes: b987e98e ("dsa: add DSA switch driver for Microchip KSZ9477")
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/microchip/ksz8795.c

@@ -1268,6 +1268,9 @@ static int ksz8795_switch_init(struct ksz_device *dev)
 			return -ENOMEM;
 	}
 
+	/* set the real number of ports */
+	dev->ds->num_ports = dev->port_cnt;
+
 	return 0;
 }
 

drivers/net/dsa/microchip/ksz9477.c

@@ -1588,6 +1588,9 @@ static int ksz9477_switch_init(struct ksz_device *dev)
 			return -ENOMEM;
 	}
 
+	/* set the real number of ports */
+	dev->ds->num_ports = dev->port_cnt;
+
 	return 0;
 }