WiFi channels

[Peter Robinson]

On Fri, Nov 6, 2009 at 8:46 PM, Daniel Drake <dsd at laptop.org> wrote:
> 2009/11/6 John Watlington <wad at laptop.org>:
>> How is the region programmed in ?
>
> In the factory where the cards are manufactured, presumably.
> Or yes, I guess it may be influenced by the firmware as you suggest.
>
> I would guess that all XO-1s produce the same region code, probably
> US, which causes the driver to limit itself to channels 1-11. I don't
> know the details but I think you could get in some trouble with the
> FCC if you were to ship devices that could work outside of the 1-11
> spectrum in the US.

You should be able to set it via a software setting. The kernel has
infra in the cfg80211 to set the regulatory domain and Fedora sets the
region on the load of the kernel module. I think Fedora sets it based
of the location/timezone setting you specify during install You see
messages like the ones below on boot. We should be able to do the same
on the olpc.

cfg80211: Calling CRDA to update world regulatory domain
cfg80211: World regulatory domain updated:
	(start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
	(2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
	(2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
	(2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
	(5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
	(5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)

Cheers,
Peter