Kernel support for 24-bit sound

[Pigeon]

I am trying to add support for the 24-bit S/PDIF input mode of my
CMI8738 sound card to the cmpci.c driver of kernel 2.4.20.

I am hindered in this chiefly by lack of documentation.

If someone could supply me with the URL of some documentation
on kernel sound handling it would be much appreciated.

I am also somewhat worried that none of the valid arguments listed for
the SNDCTL_DSP_SETFMT ioctl seem to be for any kind of 24-bit format.
Is there in fact any kernel support for 24-bit sound in general?

Please CC me on replies; I'm on dialup and I can't cope with the
traffic on this list.

Many thanks

Pigeon