I am dealing with a strange problem with wifi on my raspberry pi (I`m not sure if this has influence). I tried this with 3 different usb wifi devices. All of them are working perfectly if I connect to AP with wpa_supplicant. Troubles start when I start kismet (2011-03-R2) - I receive these error messages:
mac80211_setchannel() could not set channel 1/2412 on interface 'te0mon' err -25
The original name wifi interface name is te0, it`s configured in udev, I just needed to distinguish all my wifi devices. The same problem is with iw command:
iw te0 set channel 1
command failed: Device or resource busy (-16)
The device is down, not used by any other process (as far as I can recognize). These troubles started after upgrading to kernel 3.6.11 from 3.2.something (I don't remember this exactly). I can't downgrade it because other problems were solved by this. I even tried to download iw version 3.8 (the newest) and compatibility drivers 3.9 and it`s still the same.
Do you have any idea, what could be wrong? How to debug this (find, why the device is busy)?
Thanks for any help.