Initial commit moving openolt adapter from voltha-go to the new repo.
This version works with ponsim rather than openolt, this is temporary.
It is currently being fixed to work with openolt.

Change-Id: I34a800c98f050140b367e2d474b7aa8b79f34b9a
Signed-off-by: William Kurkian <wkurkian@cisco.com>
diff --git a/python/common/utils/deferred_utils.py b/python/common/utils/deferred_utils.py
new file mode 100644
index 0000000..3c55c1a
--- /dev/null
+++ b/python/common/utils/deferred_utils.py
@@ -0,0 +1,56 @@
+# Copyright 2017-present Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+from twisted.internet.error import AlreadyCalled
+
+
+class TimeOutError(Exception): pass
+
+
+class DeferredWithTimeout(Deferred):
+    """
+    Deferred with a timeout. If neither the callback nor the errback method
+    is not called within the given time, the deferred's errback will be called
+    with a TimeOutError() exception.
+
+    All other uses are the same as of Deferred().
+    """
+    def __init__(self, timeout=1.0):
+        Deferred.__init__(self)
+        self._timeout = timeout
+        self.timer = reactor.callLater(timeout, self.timed_out)
+
+    def timed_out(self):
+        self.errback(
+            TimeOutError('timed out after {} seconds'.format(self._timeout)))
+
+    def callback(self, result):
+        self._cancel_timer()
+        return Deferred.callback(self, result)
+
+    def errback(self, fail):
+        self._cancel_timer()
+        return Deferred.errback(self, fail)
+
+    def cancel(self):
+        self._cancel_timer()
+        return Deferred.cancel(self)
+
+    def _cancel_timer(self):
+        try:
+            self.timer.cancel()
+        except AlreadyCalled:
+            pass
+