I found one more place where -EINVAL is used instead of -ENOTTY:

Note that drivers/media/dvb/dvb-core/dvbdev.c has the same code, but as far as
I can tell DVB is still using -EINVAL for unknown ioctls so I didn't change
that.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>