can audio CDs be played with ATA_CAM ?

Claude Buisson clbuisson at
Tue Oct 25 15:01:34 UTC 2011

On 10/25/2011 15:08, Daniel O'Connor wrote:
> On 25/10/2011, at 23:24, Jeremy Chadwick wrote:
>>> These may not be the same problem, but I think they are related (a not so well
>>> documented change in the kerm interface).
>> You want atapicam(4).  This is not the same thing as "options ATA_CAM".
>> See /sys/conf/NOTES.
>> Whether or not it works with audio CDs is unknown to me.
> atapicam is a bridge for the old ATA code to put ATAPI devices _only_ on CAM (as well as the ATA infrastructure). Hence they appear as /dev/cd0 and so on.

As I said: I know it (after 16 years of FreeBSD use ...)

> ATA_CAM puts _all_ ATA devices on CAM, so you should be able to access your audio CD that way.
> I just tried and it ripped a CD fine using cdparanoia and cdcontrol seemed to play it OK (although I don't have the analogue output of this drive hooked up to the audio system).

I just played a CD with cdcontrol on a ATA_CAMed 9.0 system from Sept 25 (hooked
to the audio), but do not know what is proven that way: VLC see the tracks of
the audio CD and may even identifiy them with cddb, but cannot play them (see
the error messages). So my current conclusion (?) is that the problem lies with
the userland librairies (cdda, ..)

> This is not to say that there isn't a bug in the ATA_CAM code :)

I will do another test on 9.0 (after rebuilding the ports), and eventually get
rid of ATA_CAM and wait (im)patiently for a knowledgeable one to have a look at
the problem. If this is a real problem, I may hope that it will appear after the
release of 9.0 and its use in the real world.

> --
> Daniel O'Connor software and network engineer
> for Genesis Software -
> "The nice thing about standards is that there
> are so many of them to choose from."
>    -- Andrew Tanenbaum
> GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C

Claude Buisson

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