Support smart child modules queries (#967)

Required for the P300 firmware update with `auto_off` module on child
devices. Will query child modules for parent devices that are not hubs.

Coverage will be fixed when the P300 fixture is added
https://github.com/python-kasa/python-kasa/pull/915

kasa/smart/modules/autooff.py

@@ -99,3 +99,11 @@ class AutoOff(SmartModule):
         sysinfo = self._device.sys_info
 
         return self._device.time + timedelta(seconds=sysinfo["auto_off_remain_time"])
+
+    async def _check_supported(self):
+        """Additional check to see if the module is supported by the device.
+
+        Parent devices that report components of children such as P300 will not have
+        the auto_off_status is sysinfo.
+        """
+        return "auto_off_status" in self._device.sys_info

kasa/smart/smartchilddevice.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import logging
+from typing import Any
 
 from ..device_type import DeviceType
 from ..deviceconfig import DeviceConfig
@@ -34,7 +35,17 @@ class SmartChildDevice(SmartDevice):
         self.protocol = _ChildProtocolWrapper(self._id, parent.protocol)
 
     async def update(self, update_children: bool = True):
-        """Noop update. The parent updates our internals."""
+        """Update child module info.
+
+        The parent updates our internal info so just update modules with
+        their own queries.
+        """
+        req: dict[str, Any] = {}
+        for module in self.modules.values():
+            if mod_query := module.query():
+                req.update(mod_query)
+        if req:
+            self._last_update = await self.protocol.query(req)
 
     @classmethod
     async def create(cls, parent: SmartDevice, child_info, child_components):

kasa/smart/smartdevice.py

@@ -149,7 +149,7 @@ class SmartDevice(Device):
         if "child_device" in self._components and not self.children:
             await self._initialize_children()
 
-    async def update(self, update_children: bool = True):
+    async def update(self, update_children: bool = False):
         """Update the device."""
         if self.credentials is None and self.credentials_hash is None:
             raise AuthenticationError("Tapo plug requires authentication.")
@@ -167,9 +167,14 @@ class SmartDevice(Device):
         self._last_update = resp = await self.protocol.query(req)
 
         self._info = self._try_get_response(resp, "get_device_info")
+
+        # Call child update which will only update module calls, info is updated
+        # from get_child_device_list. update_children only affects hub devices, other
+        # devices will always update children to prevent errors on module access.
+        if update_children or self.device_type != DeviceType.Hub:
+            for child in self._children.values():
+                await child.update()
         if child_info := self._try_get_response(resp, "get_child_device_list", {}):
-            # TODO: we don't currently perform queries on children based on modules,
-            #  but just update the information that is returned in the main query.
             for info in child_info["child_device_list"]:
                 self._children[info["device_id"]]._update_internal_state(info)
 
@@ -352,8 +357,7 @@ class SmartDevice(Device):
     @property
     def time(self) -> datetime:
         """Return the time."""
-        # TODO: Default to parent's time module for child devices
-        if self._parent and Module.Time in self.modules:
+        if self._parent and Module.Time in self._parent.modules:
             _timemod = self._parent.modules[Module.Time]
         else:
             _timemod = self.modules[Module.Time]