Added info to docs to answer Q25 from Ford pending questions.

Bug: 259309511
Test: manual build
Change-Id: I21e2672ff41ad6b8fc08866641abe58dd75c8efc
diff --git a/automotive/vehicle/aidl_property/android/hardware/automotive/vehicle/VehicleProperty.aidl b/automotive/vehicle/aidl_property/android/hardware/automotive/vehicle/VehicleProperty.aidl
index 8a3ab90..fe1eb2d 100644
--- a/automotive/vehicle/aidl_property/android/hardware/automotive/vehicle/VehicleProperty.aidl
+++ b/automotive/vehicle/aidl_property/android/hardware/automotive/vehicle/VehicleProperty.aidl
@@ -484,12 +484,15 @@
      *
      * This is the gear selected by the user.
      *
-     * Values in the config data must represent the list of supported gears
-     * for this vehicle.  For example, config data for an automatic transmission
-     * must contain {GEAR_NEUTRAL, GEAR_REVERSE, GEAR_PARK, GEAR_DRIVE,
-     * GEAR_1, GEAR_2,...} and for manual transmission the list must be
+     * Values in the config data must represent the list of supported gears for this vehicle. For
+     * example, config data for an automatic transmission must contain {GEAR_NEUTRAL, GEAR_REVERSE,
+     * GEAR_PARK, GEAR_DRIVE, GEAR_1, GEAR_2,...} and for manual transmission the list must be
      * {GEAR_NEUTRAL, GEAR_REVERSE, GEAR_1, GEAR_2,...}
      *
+     * In the case of an automatic transmission vehicle that allows the driver to select specific
+     * gears on demand (i.e. "manual mode"), GEAR_SELECTION's value must be set to the specific gear
+     * selected by the driver instead of simply GEAR_DRIVE.
+     *
      * @change_mode VehiclePropertyChangeMode.ON_CHANGE
      * @access VehiclePropertyAccess.READ
      * @data_enum VehicleGear