ui: handle backlight notification

lib/logitech_receiver/notifications.py

@@ -410,6 +410,14 @@ def _process_feature_notification(device, status, n, feature):
         else:
             _log.warn('%s: unknown REPROG_CONTROLS %s', device, n)
 
+    elif feature == _F.BACKLIGHT2:
+        if (n.address == 0x00):
+            level = _unpack('!B', n.data[1:2])[0]
+            from solaar.ui.config_panel import record_setting  # prevent circular import
+            setting = next((s for s in device.settings if s.name == _st.Backlight2Level.name), None)
+            if setting:
+                record_setting(device, setting, [level])
+
     elif feature == _F.REPROG_CONTROLS_V4:
         if n.address == 0x00:
             if _log.isEnabledFor(_DEBUG):

lib/solaar/ui/config_panel.py

@@ -18,6 +18,7 @@
 
 import traceback
 
+from logging import DEBUG as _DEBUG
 from logging import WARNING as _WARNING
 from logging import getLogger
 from threading import Timer as _Timer
@@ -724,6 +725,8 @@ def record_setting(device, setting, values):
 
 
 def _record_setting(device, setting, values):
+    if _log.isEnabledFor(_DEBUG):
+        _log.debug('on %s changing setting %s to %s', device, setting, values)
     if len(values) > 1:
         setting.update_key_value(values[0], values[-1])
         value = {values[0]: values[-1]}