Revert DSMR not calling entity methods (#36179)

homeassistant/components/dsmr/sensor.py

@@ -17,10 +17,6 @@
 )
 from homeassistant.core import CoreState, callback
 from homeassistant.helpers import config_validation as cv
-from homeassistant.helpers.dispatcher import (
-    async_dispatcher_connect,
-    async_dispatcher_send,
-)
 from homeassistant.helpers.entity import Entity
 
 _LOGGER = logging.getLogger(__name__)
@@ -113,7 +109,11 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
 
     async_add_entities(devices)
 
-    update_entities_telegram = partial(async_dispatcher_send, hass, DOMAIN)
+    def update_entities_telegram(telegram):
+        """Update entities with latest telegram and trigger state update."""
+        # Make all device entities aware of new telegram
+        for device in devices:
+            device.update_data(telegram)
 
     # Creates an asyncio.Protocol factory for reading DSMR telegrams from
     # serial and calls update_entities_telegram to update entities on arrival
@@ -187,17 +187,12 @@ def __init__(self, name, obis, config):
         self._config = config
         self.telegram = {}
 
-    async def async_added_to_hass(self):
-        """When entity is added to hass."""
-        self.async_on_remove(
-            async_dispatcher_connect(self.hass, DOMAIN, self.update_data)
-        )
-
     @callback
     def update_data(self, telegram):
         """Update data."""
         self.telegram = telegram
-        self.async_write_ha_state()
+        if self.hass:
+            self.async_write_ha_state()
 
     def get_dsmr_object_attr(self, attribute):
         """Read attribute from last received telegram for this DSMR object."""