Re: can audio CDs be played with ATA_CAM ?

On 10/25/2011 14:54, Jeremy Chadwick wrote:
> On Tue, Oct 25, 2011 at 01:18:47PM +0200, Claude Buisson wrote:
>> On 10/25/2011 12:52, Daniel O'Connor wrote:
>>>
>>> On 25/10/2011, at 20:45, Claude Buisson wrote:
>>>> When upgrading a system to 8.2-STABLE, I switched my kernel from atapicam to
>>>> ATA_CAM, and found that vlc could not play audio CDs anymore. Reverting to
>>>> atapicam (and reverting from cdN to acdN of course), vlc was OK again.
>>>>
>>>> It seems that I am not the only one having this kind of problem, as I found (for
>>>> example) this message on questions_at_ (for releng9):
>>>>
>>>> http://lists.freebsd.org/pipermail/freebsd-questions/2011-October/234737.html
>>>>
>>>> Is this a known problem ? Is somebody working on it ?
>>>
>>> Have you tried pointing VLC at /dev/cd0 when using ATA_CAM?
>>>
>>
>> Of course yes ! (I even configured WITH_CDROM_DEVICE=/dev/cd1 when building VLC)
>>
>>
>>> It may be trying old style ATA ioctls based on the device name.
>>>
>>
>> VLC recognize the tracks and jump quickly from one to the following, without
>> playing it, and with a flow of messages:
>>
>> [0x2caf2a3c] cdda access error: Could not set block size
>> [0x2caf2a3c] cdda access error: cannot read sector nnnnn
>>
>> where the sector number is incremented, and then emit (2 times if I remenber):
>>
>> [0x2af28bc] es demux error: cannot peek
>>
>> Sorry for having ommited these messages in the previous mail.
>>
>> I found a PR 161760 about cdparanoia needing to be patched for 9.0 with CAM, a
>> proposal by avg_at_ related to libxine:
>>
>> http://lists.freebsd.org/pipermail/freebsd-multimedia/2010-December/011414.html
>>
>> 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.
>

I *know* the difference between atapicam and ATA_CAM ;-)

I have done other tests on 8.X and 7.X, and found that audio CDs cannot be
played with atapicam.

BUT, I understood (wrongly ?) that ATA_CAM was the way to go starting with 9.X,
which imply that the traditionnal acdN interface will disappear.

A valid answer to my question may be: "we - kernel developpers - know about it,
but we don't care, and the problem must be solved by the userland/applications
developpers".

With some obvious consequences on the upgrading or not upgrading of end users
systems.

Claude Buisson