at76_usb driver supports USB devices using Atmel at76c50x chipsets. Only 802.11b protocol is supported. The driver is using mac80211 stack.
The original at76_usb driver which had it's own 802.11 stack but based on the feedback in linux-wireless a mac80211 port was started. The mac80211 port is currently unstable but work is underway to get it to work better. Help is very welcome.
The original at76_usb git tree was here:
But it seems to be gone now. The current mac80211 port is in linux-testing and the history for the driver is here:
Some Atmel wireless cards require firmware to be loaded. The firmware can be downloaded from this site: