Chipset: Atheros AR2425
The WiFi card comes set to regdom
0x65 (World/ETSI C) which limits the channels to 1..11. (
iw list shows channels 12..14 as disabled.) In Germany, there are also channels 12 and 13 which are unusable this way. But there’s the tool
ath_info which can read and write the EEPROM on the card and thus also the regdomain.
First, find the base address of the adapter using
Mine was at address
75200000. Now you can dump the contents of the EEPROM using
To write the EEPROM, you have to unlock it by setting a GPIO register, namely the first, to zero. I changed the regdomain to
0x00 (=ALL channels available) 0x68 (=EU1 World) using this command:
ath_info -g 1:0 -w 0x75200000 regdomain 68
You can find all valid codes by looking at the
DMN_ constants in the regdom.h file.
After unloading the modules:
cfg80211 and doing a
modprobe ath5k, the command
iw list should show the two new channels enabled.
For older ieee80211 modules, there’s a module option
ieee80211_regdom for the
cfg80211 module. This takes the values
EU. Add the following lines to
options cfg80211 ieee80211_regdom=EU options lbm_cw_cfg80211 ieee80211_regdom=EU
And after a reboot, you will have channels 12 and 13 available.
On Jaunty, you have to install the package
iw and use the following command in e.g. your
/etc/rc.local to set the regdomain to Germany:
iw reg set DE
If you get the message
MAC revision 0xffff is not supported! it means that some other module, likely
ath_pci took over your card.