USB wifi key: how to unlock european channels 12 and 13?

Question

Context

A USB Wifi dongle bought in Paris, France, is identified on Linux (Debian, Ubuntu, Mint same behavior) as ID 0846:9021 NetGear, Inc. It works well with Wifi networks in channels 1-11.

Problem

It does not see channels above 11 and Wifi networks on those channels.

Additional information

There is information about channels on en:developers:documentation:channellist [Linux Wireless]. It appears that channels 12 and 13 are valid in Europe not in US.

Attempted cure

Based on an old IRC conversation on #linux-wireless, I tried:

iw reg set FR
iw reg set EU

It changes nothing.

iwlist wlan1 channel

wlan1     11 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz

For comparison, another Wifi adapter shows this:

iwlist wlan0 channel

wlan0     32 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Channel 36 : 5.18 GHz
          Channel 40 : 5.2 GHz
          Channel 44 : 5.22 GHz
          Channel 48 : 5.24 GHz
          Channel 52 : 5.26 GHz
          Channel 56 : 5.28 GHz
          Channel 60 : 5.3 GHz
          Channel 64 : 5.32 GHz
          Channel 100 : 5.5 GHz
          Channel 104 : 5.52 GHz
          Channel 108 : 5.54 GHz
          Channel 112 : 5.56 GHz
          Channel 116 : 5.58 GHz
          Channel 120 : 5.6 GHz
          Channel 124 : 5.62 GHz
          Channel 128 : 5.64 GHz
          Channel 132 : 5.66 GHz
          Channel 136 : 5.68 GHz
          Channel 140 : 5.7 GHz
          Current Frequency:5.18 GHz (Channel 36)

Question

Of course, I don't expect to magically enable the 5GHz band on hardware that does not support it, but it's certainly possible to unlock channels 12 and 13, because that device was bought in Paris.

My guess is: such devices are sent worldwide with a US configuration and are intended to be used on Windows where drivers have access to some API to adjust frequency range.

Is there a Linux-based solution to unlock channels 12 and 13?

Answer 1

According to https://ttys1.wordpress.com/2012/04/12/fixing-regulatory-domain-crda-of-realtec-wireless-device-drivers/ Realtek driver has hardcoded CRDA settings and need to be fixed manually.