``binder-control`` device cannot be deleted since this would make the binderfs
instance unusable. The ``binder-control`` device will be deleted when the
binderfs instance is unmounted and all references to it have been dropped.
+
+Binder features
+---------------
+
+Assuming an instance of binderfs has been mounted at ``/dev/binderfs``, the
+features supported by the binder driver can be located under
+``/dev/binderfs/features/``. The presence of individual files can be tested
+to determine whether a particular feature is supported by the driver.
+
+Example::
+
+ cat /dev/binderfs/features/oneway_spam_detection
+ 1