Add support for custom configurations in ZHA (#48423)

* initial configuration options

* first crack at saving the data

* constants

* implement initial options

* make more dynamic

* fix unload and reload of the config entry

* update unload

homeassistant/components/zha/core/helpers.py

@@ -24,7 +24,14 @@ import zigpy.zdo.types as zdo_types
 
 from homeassistant.core import State, callback
 
-from .const import CLUSTER_TYPE_IN, CLUSTER_TYPE_OUT, DATA_ZHA, DATA_ZHA_GATEWAY
+from .const import (
+    CLUSTER_TYPE_IN,
+    CLUSTER_TYPE_OUT,
+    CUSTOM_CONFIGURATION,
+    DATA_ZHA,
+    DATA_ZHA_GATEWAY,
+    ZHA_OPTIONS,
+)
 from .registries import BINDABLE_CLUSTERS
 from .typing import ZhaDeviceType, ZigpyClusterType
 
@@ -122,6 +129,16 @@ def async_is_bindable_target(source_zha_device, target_zha_device):
     return False
 
 
+@callback
+def async_get_zha_config_value(config_entry, config_key, default):
+    """Get the value for the specified configuration from the zha config entry."""
+    return (
+        config_entry.options.get(CUSTOM_CONFIGURATION, {})
+        .get(ZHA_OPTIONS, {})
+        .get(config_key, default)
+    )
+
+
 async def async_get_zha_device(hass, device_id):
     """Get a ZHA device for the given device registry id."""
     device_registry = await hass.helpers.device_registry.async_get_registry()