Re: ath9k 9380: All 5Ghz channels flagged as passive-scanning

From: Ben Greear <greearb@candelatech.com>
To: "Luis R. Rodriguez" <mcgrof@gmail.com>
Cc: David Quan <David.Quan@atheros.com>,
	Mohammed Shafi <shafi.wireless@gmail.com>,
	"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
Subject: Re: ath9k 9380: All 5Ghz channels flagged as passive-scanning
Date: Mon, 23 May 2011 21:48:46 -0700	[thread overview]
Message-ID: <4DDB38AE.1060600@candelatech.com> (raw)
In-Reply-To: <BANLkTimxFnWezBE7WCBHyQjJcrZ3WuTwuQ@mail.gmail.com>

On 05/23/2011 03:15 PM, Luis R. Rodriguez wrote:
> On Mon, May 23, 2011 at 2:59 PM, Ben Greear<greearb@candelatech.com>  wrote:
>> On 05/23/2011 02:46 PM, Luis R. Rodriguez wrote:
>>>
>>> On Mon, May 23, 2011 at 2:42 PM, Luis R. Rodriguez<mcgrof@gmail.com>
>>>   wrote:
>>>
>>>> No. You can only do this by trying to take the card out of compliance
>>>> purposely or unknowingly in software.
>>>
>>> Oh and my point was that "regulatory hacks" fit this description.
>>
>> Ok.  I believe you are right in general, but I can't see how enabling
>> a device to work on a non-scanned channel can break something,
>
> If a card is world roaming, how else on earth without seeing a beacon
> will you know if you can initiate radiation on that channel?

I have a strong personal sense of location, and I'm 100% sure that
I'm in the US.  So, the the computer could listen to it's human
and just trust that I know WTF I am asking for!

It may currently be impossible for vendors to explicitly support
this due to regulatory domains that assume users are evil and/or
stupid and not to be trusted to know their current location,
but please don't pretend that receiving a beacon is rock solid
evidence of a channel's availability:  It only means that someone
else that set up the AP thinks it's available for use.

>> if it is perfectly legal and appropriate for there to be an AP on that
>> scanned channel.
>
> Agreed! In fact I'd go so far as to say that if you have multiple
> 802.11 cards they should be able to share the same beacon hints, and
> in fact -- this is what cfg80211 does ;)
>
>> In other words, if I change my Netgear to be on channel
>> 48, scanned it, and then created a VAP on that channel, that is OK with
>> un-hacked regdomain stuff, but if instead I change regdomain to 0x0
>> and use channel 48 without re-configuring my Netgear, somehow that
>> suddenly causes issues?
>
> For Atheros EEPROM 0x0 is designed for usage for the US:

Good..that's all I really wanted:  My NIC to support my
location w/out undue complaint or limitations.

Thanks,
Ben

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