Bring back delayed zwave value update behavior (#2674)

homeassistant/components/light/zwave.py

@@ -8,6 +8,7 @@ import logging
 
 # Because we do not compile openzwave on CI
 # pylint: disable=import-error
+from threading import Timer
 from homeassistant.components.light import ATTR_BRIGHTNESS, ATTR_COLOR_TEMP, \
     ATTR_RGB_COLOR, DOMAIN, Light
 from homeassistant.components import zwave
@@ -108,7 +109,22 @@ class ZwaveDimmer(zwave.ZWaveDeviceEntity, Light):
         """Called when a value has changed on the network."""
         if self._value.value_id == value.value_id or \
            self._value.node == value.node:
-            self.update_properties()
+
+            if self._refreshing:
+                self._refreshing = False
+                self.update_properties()
+            else:
+                def _refresh_value():
+                    """Used timer callback for delayed value refresh."""
+                    self._refreshing = True
+                    self._value.refresh()
+
+                if self._timer is not None and self._timer.isAlive():
+                    self._timer.cancel()
+
+                self._timer = Timer(2, _refresh_value)
+                self._timer.start()
+
             self.update_ha_state()
 
     @property