Anyone used HDA/AC97 codec with ARM uC?
I found the data sheet for the ALC880:

http://realtek.info/pdf/alc880.pdf

You will have problems interfacing it to an ARM, as it uses S/PDIF and an unusual high-speed serial interface. It could be done with a CPLD. Or, you could forget the ARM and do everything with an XMOS chip. The interface could be done in software, and the chips have DSP capability. They are often used for high-end audio processing.

The data sheet suggests that designers contact Realtek for details of application circuits, perhaps you should try that.

The other codec is probably similar.