I encountered the same issue on 3.2.0-4-amd64
dmesg : ath5k phy0: Atheros AR2425 chip
lspci : Ethernet controller: Atheros Communications Inc. AR242x / AR542x Wireless Network Adapter (PCI-Express) (rev 01)
My solution :
Add
# Backports
to your sources.list ( replace url with your favourite repository )
then
sudo apt-get update
sudo apt-get install firmware-linux-nonfree
Hope this helps.
--
--
Cas Renooij