Found a little bit more information with some digging.
The reason this system is not directly supported by OpenWRT trunk (and thus Gargoyle) is because the stock Broadcom wifi driver has licensing issues and cannot be distributed by OpenWRT - despite the fact that it's open source.
Additionally, the 'b43' and 'b43legacy' drivers in the mainline kernel do
not support the wireless chipset in the RT-N16.
The reason DD-WRT and TomatoUSB work is because they include the Broadcom driver.
Now for the good news!
George Kashperko has recently (January 2012) been putting in a lot of work to hack the Broadcom driver into OpenWRT. This is not an ideal solution, but it's better than nothing.
See his
patching howto if you want to try building, or try what looks like a prebuilt
trx firmware image.
For future non-devs reading this, you can
install Gargoyle easily on top of OpenWRT once it's installed.
Oh, and
work is underway to reverse-engineer the Broadcom GMAC core. This means that we should one day have fully open-source drivers in OpenWRT - probably by 2015 or so. Yay.
Now the question. What are Gargoyle's policies with respect to distribution of 'questionable' drivers? Obviously TomatoUSB and DD-WRT are doing it without any consequences.
