Don't poll entities for unavailable ZHA devices (#39756)

* Don't poll entities for unavailable ZHA devices

* Update homeassistant/components/zha/entity.py

Co-authored-by: Bas Nijholt <basnijholt@gmail.com>

* cleanup after accepting suggestion

Co-authored-by: Bas Nijholt <basnijholt@gmail.com>

homeassistant/components/zha/entity.py

@@ -202,9 +202,13 @@ class ZhaEntity(BaseZhaEntity, RestoreEntity):
 
     async def async_update(self) -> None:
         """Retrieve latest state."""
-        for channel in self.cluster_channels.values():
-            if hasattr(channel, "async_update"):
-                await channel.async_update()
+        tasks = [
+            channel.async_update()
+            for channel in self.cluster_channels.values()
+            if hasattr(channel, "async_update")
+        ]
+        if tasks:
+            await asyncio.gather(*tasks)
 
 
 class ZhaGroupEntity(BaseZhaEntity):

homeassistant/components/zha/light.py

@@ -410,13 +410,10 @@ class Light(BaseLight, ZhaEntity):
         if "effect" in last_state.attributes:
             self._effect = last_state.attributes["effect"]
 
-    async def async_update(self):
-        """Attempt to retrieve on off state from the light."""
-        await super().async_update()
-        await self.async_get_state()
-
     async def async_get_state(self, from_cache=True):
         """Attempt to retrieve on off state from the light."""
+        if not from_cache and not self.available:
+            return
         self.debug("polling current state - from cache: %s", from_cache)
         if self._on_off_channel:
             state = await self._on_off_channel.get_attribute_value(

homeassistant/components/zha/sensor.py

@@ -210,6 +210,12 @@ class ElectricalMeasurement(Sensor):
             return round(value, self._decimals)
         return round(value)
 
+    async def async_update(self) -> None:
+        """Retrieve latest state."""
+        if not self.available:
+            return
+        await super().async_update()
+
 
 @STRICT_MATCH(generic_ids=CHANNEL_ST_HUMIDITY_CLUSTER)
 @STRICT_MATCH(channel_names=CHANNEL_HUMIDITY)