Ensure generate_entity_id returns valid entity ids

homeassistant/helpers/__init__.py

@@ -2,7 +2,8 @@
 Helper methods for components within Home Assistant.
 """
 from homeassistant.loader import get_component
-from homeassistant.const import ATTR_ENTITY_ID, CONF_PLATFORM
+from homeassistant.const import (
+    ATTR_ENTITY_ID, CONF_PLATFORM, DEVICE_DEFAULT_NAME)
 from homeassistant.util import ensure_unique_string, slugify
 
 # Deprecated 3/5/2015 - Moved to homeassistant.helpers.entity
@@ -12,6 +13,7 @@ from .entity import Entity as Device, ToggleEntity as ToggleDevice  # noqa
 
 def generate_entity_id(entity_id_format, name, current_ids=None, hass=None):
     """ Generate a unique entity ID based on given entity IDs or used ids. """
+    name = name.lower() or DEVICE_DEFAULT_NAME.lower()
     if current_ids is None:
         if hass is None:
             raise RuntimeError("Missing required parameter currentids or hass")