Move lock methods to base class

src/cocotb_bus/drivers/__init__.py

@@ -81,6 +81,8 @@ def __init__(self):
         """Constructor for a driver instance."""
         self._pending = Event(name="Driver._pending")
         self._sendQ = deque()
+        self.busy_event = Event("Driver._busy")
+        self.busy = False
 
         # Sub-classes may already set up logging
         if not hasattr(self, "log"):
@@ -89,6 +91,16 @@ def __init__(self):
         # Create an independent coroutine which can send stuff
         self._thread = cocotb.scheduler.add(self._send_thread())
 
+    async def _acquire_lock(self):
+        if self.busy:
+            await self.busy_event.wait()
+        self.busy_event.clear()
+        self.busy = True
+
+    def _release_lock(self):
+        self.busy = False
+        self.busy_event.set()
+
     def kill(self):
         """Kill the coroutine sending stuff."""
         if self._thread:

src/cocotb_bus/drivers/avalon.py

@@ -79,22 +79,10 @@ class AvalonMaster(AvalonMM):
     def __init__(self, entity, name, clock, **kwargs):
         AvalonMM.__init__(self, entity, name, clock, **kwargs)
         self.log.debug("AvalonMaster created")
-        self.busy_event = Event("%s_busy" % name)
-        self.busy = False
 
     def __len__(self):
         return 2**len(self.bus.address)
 
-    async def _acquire_lock(self):
-        if self.busy:
-            await self.busy_event.wait()
-        self.busy_event.clear()
-        self.busy = True
-
-    def _release_lock(self):
-        self.busy = False
-        self.busy_event.set()
-
     @coroutine
     async def read(self, address: int, sync: bool = True) -> BinaryValue:
         """Issue a request to the bus and block until this comes back.

src/cocotb_bus/drivers/opb.py

@@ -31,18 +31,6 @@ def __init__(self, entity, name, clock, **kwargs):
         BusDriver.__init__(self, entity, name, clock, **kwargs)
         self.bus.select.setimmediatevalue(0)
         self.log.debug("OPBMaster created")
-        self.busy_event = Event("%s_busy" % name)
-        self.busy = False
-
-    async def _acquire_lock(self):
-        if self.busy:
-            await self.busy_event.wait()
-        self.busy_event.clear()
-        self.busy = True
-
-    def _release_lock(self):
-        self.busy = False
-        self.busy_event.set()
 
     @cocotb.coroutine
     async def read(self, address: int, sync: bool = True) -> BinaryValue: