diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
index 77f3cee3af0d15892eff5029938e8d1449b7cfcb..49e3a0cb1b5b3e8150d726466d5b22b033995054 100644
--- a/drivers/net/dsa/lan9303-core.c
+++ b/drivers/net/dsa/lan9303-core.c
@@ -20,6 +20,8 @@
 
 #include "lan9303.h"
 
+#define LAN9303_NUM_PORTS 3
+
 /* 13.2 System Control and Status Registers
  * Multiply register number by 4 to get address offset.
  */