good god, OMAP3530 pin multiplexing is complex and convoluted. basically, there are more functions than there are output pins, so you have to set "modes" on a pin, and it routes to one of (seven i think) functions.

start-up initialisation can either be done by u-boot or, if you define CONFIG_OMAP_MUX, by the linux kernel. the linux kernel source is such a dog's dinner that people recommend it be done by u-boot.

so i _think_ i've worked out that the IGEP-v2 has McBSP3 on the default u-boot pins 4,6,8 and 10. that leaves just a bit of wiring, putting 1.8v output as well to one side of the MAX3378 level converter.

i've also discovered that VAUX1 is a controllable output (from the modem! yaay! AT#VAUX=0 or 1) which provides CMOS 2.6v levels, yaay! actually it's nominally around 2.9v which is what's required to power CMOS 2.6v.

so, that's going on the other side of the MAX3378.

bar a few AT commands, i will then have the Digital PCM Audio of the UC864 connected to the McBSP of an OMAP3530, yaay!

next all i have to do is write the device driver...