HomeDistributionsSecurityCryptographyGamesFAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Redhat > Fedora Development

 
 
LinkBack Thread Tools
 
Old 04-29-2008, 11:37 AM
Tomasz Torcz
 
Default iwl3945 driver channel capability

Dnia 29-04-2008, wto o godzinie 12:19 +0100, Camilo Mesias pisze:
> Hi,
>
> does anyone know what determines the range of channels available with
> this driver? I ask after spending some time debugging a network set to
> channel 13, where most devices worked fine but the iwl3945 driven
> device in the laptop would not scan beyond channel 11.
>

> The iwl3945 website talks about a 'userspace regulatory daemon' which
> has been replaced by logic in the firmware. How then do we tell the
> firmware which region it is in?

Some time ago I was corresponding with Intel Engineer James Ketrenos
about this issue. I will quote his reply:

#v+
The driver and daemon only support the channels for which the specific
card has been configured for use. There is no user selectable override
of the factory configuration--it is hard coded based on what the laptop
manufacturer provided.

There are various versions of the 3945 with each calibrated to operate
in different geographical locations based on local regulations. The
laptop manufacturer selects which card to install into the laptop based
on what would be compatible with the geographies they are selling the
laptop into.
#v-

So your card is crippled to 11 channels (like mine) on hardware level.
This is very probably not modifiable in any way.

--
Tomasz Torcz

--
fedora-devel-list mailing list
fedora-devel-list@redhat.com
https://www.redhat.com/mailman/listinfo/fedora-devel-list
 
Old 04-29-2008, 12:02 PM
"Camilo Mesias"
 
Default iwl3945 driver channel capability

Tomasz

> So your card is crippled to 11 channels (like mine) on hardware level.
> This is very probably not modifiable in any way.

Thanks for your reply, not what I wanted to hear but it's better to
have the knowledge than to be in the dark

-Cam

--
fedora-devel-list mailing list
fedora-devel-list@redhat.com
https://www.redhat.com/mailman/listinfo/fedora-devel-list
 
Old 04-29-2008, 12:23 PM
"John W. Linville"
 
Default iwl3945 driver channel capability

On Tue, Apr 29, 2008 at 01:02:22PM +0100, Camilo Mesias wrote:

> > So your card is crippled to 11 channels (like mine) on hardware level.
> > This is very probably not modifiable in any way.
>
> Thanks for your reply, not what I wanted to hear but it's better to
> have the knowledge than to be in the dark

This is presumably only true if you acquired your hardware in the USA.

What James told you is true but incomplete. Some hardware (including
the iwl3945 and iwl4965) will refuse to tune to channels that are
not on the "approved" list according to their firmware. However,
this is not the only possible restriction.

The mac80211 component will restrict the tunable channels as well,
according to it's configured regulatory region. The default region
is 'US', corresponding to the regulations specified by the FCC.
Currently there is one other region defined, 'JP', corresponding to
the regulations specified by the MKK in Japan. There currently is
not a region specified for Europe, although there is some discussion
about including one. In the long run we will likely support a more
flexible regulatory enforcement scheme, allowing for a wide variety
of localized regulations.

Anyway, if you want access to more channels you might try adding a
line like this to /etc/modprobe.conf:

options cfg80211 ieee80211_regdom='JP'

That should enable channels 1 through 14 -- be sure only to use
channels approved in your area.

Hth!

John
--
John W. Linville
linville@redhat.com

--
fedora-devel-list mailing list
fedora-devel-list@redhat.com
https://www.redhat.com/mailman/listinfo/fedora-devel-list
 
Old 04-29-2008, 12:40 PM
"Camilo Mesias"
 
Default iwl3945 driver channel capability

John,

that's interesting, I'll certainly try it. I suspect it won't make a
difference, because there are three Fedora 8 laptops here with
different chipsets (one 2200, one bcm, one 3945), all configured more
or less the same. Two work as-is with channel 13 but the iwl3945
doesn't.

-Cam

--
fedora-devel-list mailing list
fedora-devel-list@redhat.com
https://www.redhat.com/mailman/listinfo/fedora-devel-list
 
Old 04-29-2008, 01:45 PM
"John W. Linville"
 
Default iwl3945 driver channel capability

On Tue, Apr 29, 2008 at 01:40:29PM +0100, Camilo Mesias wrote:

> that's interesting, I'll certainly try it. I suspect it won't make a
> difference, because there are three Fedora 8 laptops here with
> different chipsets (one 2200, one bcm, one 3945), all configured more
> or less the same. Two work as-is with channel 13 but the iwl3945
> doesn't.

ipw2200 uses its own regulatory enforcement.

If "bcm" means the b43 driver, and you can configure channel 13,
and you haven't already applied the change to modprobe.conf mentioned
earlier, than please file a bug. :-)

Thanks,

John
--
John W. Linville
linville@redhat.com

--
fedora-devel-list mailing list
fedora-devel-list@redhat.com
https://www.redhat.com/mailman/listinfo/fedora-devel-list
 

Thread Tools




All times are GMT. The time now is 07:41 AM.

VBulletin, Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org