diff --git a/python/adapters/openolt/openolt_platform.py b/python/adapters/openolt/openolt_platform.py
index a52d653..9f63af0 100644
--- a/python/adapters/openolt/openolt_platform.py
+++ b/python/adapters/openolt/openolt_platform.py
@@ -114,7 +114,7 @@
         if intf_type is Port.ETHERNET_NNI:
             return (0x1 << 16) | intf_id
         elif intf_type is Port.PON_OLT:
-            return 0x2 << 28 | intf_id
+            return (0x2 << 28) | intf_id
         else:
             raise Exception('Invalid port type')