diff --git a/homeassistant/components/local_file/camera.py b/homeassistant/components/local_file/camera.py
index 6e665ccd1c2..9226cf7260e 100644
--- a/homeassistant/components/local_file/camera.py
+++ b/homeassistant/components/local_file/camera.py
@@ -9,6 +9,7 @@ import voluptuous as vol
 
 from homeassistant.components.camera import PLATFORM_SCHEMA, Camera
 from homeassistant.const import ATTR_ENTITY_ID, CONF_FILE_PATH, CONF_NAME
+from homeassistant.core import ServiceCall
 from homeassistant.helpers import config_validation as cv
 
 from .const import DATA_LOCAL_FILE, DEFAULT_NAME, DOMAIN, SERVICE_UPDATE_FILE_PATH
@@ -24,7 +25,7 @@ PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
 
 CAMERA_SERVICE_UPDATE_FILE_PATH = vol.Schema(
     {
-        vol.Optional(ATTR_ENTITY_ID): cv.comp_entity_ids,
+        vol.Required(ATTR_ENTITY_ID): cv.comp_entity_ids,
         vol.Required(CONF_FILE_PATH): cv.string,
     }
 )
@@ -39,16 +40,15 @@ def setup_platform(hass, config, add_entities, discovery_info=None):
     camera = LocalFile(config[CONF_NAME], file_path)
     hass.data[DATA_LOCAL_FILE].append(camera)
 
-    def update_file_path_service(call):
+    def update_file_path_service(call: ServiceCall) -> None:
         """Update the file path."""
-        file_path = call.data.get(CONF_FILE_PATH)
-        entity_ids = call.data.get(ATTR_ENTITY_ID)
+        file_path = call.data[CONF_FILE_PATH]
+        entity_ids = call.data[ATTR_ENTITY_ID]
         cameras = hass.data[DATA_LOCAL_FILE]
 
         for camera in cameras:
             if camera.entity_id in entity_ids:
                 camera.update_file_path(file_path)
-        return True
 
     hass.services.register(
         DOMAIN,