FreeBSD vs Region Code DVDs

[Ulrich Spoerlein]

On 5/4/07, Scott Long <scottl at samsco.org> wrote:
> > Why can I read and mount the DVD, but mplayer/xine
> > are still unable to play the DVD? (It works fine on the internal, ATA
> > attached, crappy NEC drive.)
>
> No idea, sorry.  Do you have umass, atapicam, and ata-usb all involved
> here?  If so, you've made the room a little crowded, and they are all
> arguing with each other.  I know that ata-usb was inspired by the ata
> author having problems with umass and not wanting to fix them there,
> but I don't know exactly what was broken or what was fixed.

I only tested one subsystem at a time, and it is not that one
subsystem is broken per se, it is only in combination with this single
external Plextor drive. I had another external DVD drive (can't
remember the brand) a few months ago and this also was working just
fine.

I'll try to sum it all up:

Internal NEC drive, attached via ata(4): Can read all kinds of CD/DVD
Internal NEC drive, attached via atapicam(4): dito
Unknown Brand external DVD, attached via umass(4): dito

External Plextor, attached via umass(4): Can read CDs, DVD-Rs, unable
to do _anything_ with retail DVD(-Video)
External Plextor, attached via firewire/sbp(4): dito
External Plextor, attached via atausb(4): Can read CDs, DVD-Rs, can
mount/read retail DVD(-Video), produces some errors, tough. The CSS
decoder seems to fail, as I can't watch the video on the drive. I can
at least _access_ the bytes though, something not possible with
umass/sbp.

I don't know the code, but it looks like this Plextor and cd(4) don't
get along when DVD copy protection is involved. I also read in the
OpenBSD 4.1 release notes, that they made changes to their cd(4) to
work better with region protected DVDs. I didn't know that the OS was
involved in this, I thought this was a thing left to the drive
firmware or the DVD player software.

Anyway, how can I tell cd(4) to give me more error output? How can I
access the DVD at the bottom-most layer? Something line sending a Test
Unit Ready command? Or checking if the drive recognizes an inserted
medium?

Uli