can audio CDs be played with ATA_CAM ?

Craig Rodrigues rodrigc at
Wed Oct 26 19:37:48 UTC 2011

On Wed, Oct 26, 2011 at 9:57 AM, Claude Buisson <clbuisson at> wrote:
> Doing my home work step by step:
> I found only 1 place in VLC where the first message:
> [0x2caf2a3c] cdda access error: Could not set block size
> is emitted, after an:
> ioctl( p_vcddev->i_device_handle, CDRIOCSETBLOCKSIZE, &i_size )
> CDRIOCSETBLOCKSIZE is defined in sys/cdrio.h, and in the kernel used in:
> sys/dev/ata/atapi-cd.c
> which is a brought into the kernel by:
> device atapicd
> So the natural question is:
> Is this ioctl supported with ATA_CAM (and atapicam) ?
> If not, what is to be used instead ?


Thanks for digging into this a bit.

I just added some code to make it easier for applications to detect
at runtime if ATA_CAM has been configured in the kernel:

I am not 100% sure how the CD driver works with ATA_CAM.

I think you might need to look at:


and also read the cd(4) man page.

We may need to extend scsi_cd.c, but I'm not sure.

Craig Rodrigues
rodrigc at

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