Message-ID: <4CA206F0.40607@candelatech.com>
Date: Tue, 28 Sep 2010 08:17:04 -0700
From: Ben Greear <greearb@candelatech.com>
MIME-Version: 1.0
To: Johannes Berg <johannes@sipsolutions.net>
CC: linux-wireless@vger.kernel.org
Subject: Re: [PATCH 2/2] mac80211:  Allow scanning single channel if other
 VIF is associated.
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On 09/28/2010 06:57 AM, Johannes Berg wrote:
> On Tue, 2010-09-28 at 06:50 -0700, Ben Greear wrote:
>
>> At best, it would be a race for wpa_s to determine if any other interface
>> on it's interface's hardware is associated, so I don't see a good way to
>> do this in user-space.
>>
>> When at least one is associated, I don't want the NIC to go offchannel at all,
>> at least not for wpa_s scanning.  Anything else is going to interrupt other
>> stations's traffic, and for no good reason that I can see, since the scanning
>> interface must associate on the same channel as the rest of the stations
>> anyway.
>>
>> If you have any suggestions for how to accomplish this, please let me know..
>> otherwise, I can just carry this patch in my tree.
>
> You can run all networks in a single wpa_s instance, I believe, and then
> it'd know about all this, right?

But then, if you want to add an additional interface, you have to restart
everything.

I was thinking that maybe I could keep the logic in wpa_s, but instead of
all the special casing, just locate the current associated channel for the
phy in question and populate the scan-req with that single channel.

Then, I think I wouldn't have to muck with much of the scan logic..just
a bit of code on the entry point to select the proper channel.

Does that sound like a possible solution to you?

Thanks,
Ben

>
> johannes


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com