VOL-470 - Support VENET as open flow port

Change-Id: I21c6923860b2bb9a386f3332720593b6517d2844
diff --git a/voltha/core/logical_device_agent.py b/voltha/core/logical_device_agent.py
index 083f42e..1d8fe4b 100644
--- a/voltha/core/logical_device_agent.py
+++ b/voltha/core/logical_device_agent.py
@@ -627,10 +627,14 @@
             ]
             assert len(upstream_ports) == 1
             downstream_ports = [
-                port for port in ports if port.type == Port.PON_OLT
+                port for port in ports if port.type == Port.PON_OLT \
+                                            or port.type == Port.VENET_OLT
             ]
-            assert len(downstream_ports) == 1, \
-                'Initially, we only handle one PON port'
+            _is_any_venet_port = any(_port.type == Port.VENET_OLT for _port in
+                                  downstream_ports)
+            if _is_any_venet_port != True:
+                assert len(downstream_ports) == 1, \
+                    'Initially, we only handle one PON port'
             flows = OrderedDict((f.id, f) for f in [
                 mk_flow_stat(
                     priority=2000,
@@ -651,13 +655,14 @@
         def leaf_device_default_rules(device):
             ports = self.root_proxy.get('/devices/{}/ports'.format(device.id))
             upstream_ports = [
-                port for port in ports if port.type == Port.PON_ONU
+                port for port in ports if port.type == Port.PON_ONU \
+                                            or port.type == Port.VENET_ONU
             ]
             assert len(upstream_ports) == 1
             downstream_ports = [
                 port for port in ports if port.type == Port.ETHERNET_UNI
             ]
-            assert len(downstream_ports) == 1
+            # assert len(downstream_ports) == 1
             flows = OrderedDict((f.id, f) for f in [
                 mk_flow_stat(
                     priority=500,
diff --git a/voltha/protos/device.proto b/voltha/protos/device.proto
index 15db1f1..30baf34 100644
--- a/voltha/protos/device.proto
+++ b/voltha/protos/device.proto
@@ -174,6 +174,8 @@
         ETHERNET_UNI = 2;
         PON_OLT = 3;
         PON_ONU = 4;
+        VENET_OLT = 5;
+        VENET_ONU = 6;
     }
 
     uint32 port_no = 1;  // Device-unique port number