According the coding style guidelines, the ENOSYS error code must be returned in case of a non existent system call. This code has been replaced with the ENOTTY error code indicating a missing functionality. Signed-off-by: Yves Lemée <yves.lemee.kernel@gmail.com> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>