Got a 3.7rc1 kernel running.
The mwifiex_sdio kernel module seems to allow the WiFi adapter to simultaneously act as client and AP (and p2p, whatever that is). When the WiFi PHY comes up, it creates three interfaces: mlan0, uap0, and p2p0.
I'm not sure how to configure uap0 to make things work. It seems I can't just set the SSID through iwconfig. I ran hostapd, and while it failed to create the monitor interface it normally uses, I did start seeing SSID broadcasts from my AP, and I could associate with it. I couldn't get full network connectivity, but that may have just been due to my IPTables rules being too strict or somesuch. I didn't get the chance to find out because apparently if you kill hostapd, the system locks. No kernel panic messages on the serial port; it just dies.
Also, things seem to be alright if I modprobe mwifiex_sdio myself, but the one time I removed it from the blacklist and it was loaded on boot, the system hung. Haven't checked whether it's repeatable, but it's more than a little frightening.
Anyway, this is looking pretty interesting. If anyone is interested in fiddling with this, I could post up the config I'm using (although it's really just an updated version of one from http://www.xilka.com/
). I could probably get the uImage and modules up somewhere as well, but this probably isn't something stable enough for general usage. Actually, it's probably a terrible idea to use this if you don't have a JTAG box.