1) changing b43 so it knows how to talk not just to
SSB/PCI/PCMCIA chips but also SDIO chips

Feng, for this you could use another b43 card with SDIO, which 
doesn't use the LP-PHY, but the older phy. If you find such a 
device, you'll be start to code this now. As the SDIO-via-SSB 
code is identical to b43-with-LP-PHY and b43-without-LP-PHY, can 
you transfer all of this.

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