Message-ID: <4BA29F58.7040101@lwfinger.net>
Date: Thu, 18 Mar 2010 16:47:04 -0500
From: Larry Finger <Larry.Finger@lwfinger.net>
MIME-Version: 1.0
To: Johannes Berg <johannes@sipsolutions.net>
CC: Michael Buesch <mb@bu3sch.de>,
	bcm43xx devel <Bcm43xx-dev@lists.berlios.de>,
	wireless <linux-wireless@vger.kernel.org>
Subject: Re: RFC: A workaround for BCM43XX devices with no on-board SPROM
References: <4BA266FB.1080507@lwfinger.net>	 <1268945580.4005.15.camel@jlt3.sipsolutions.net>	 <4BA296BA.7000502@lwfinger.net> <1268947248.4005.16.camel@jlt3.sipsolutions.net>
In-Reply-To: <1268947248.4005.16.camel@jlt3.sipsolutions.net>
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Sender: linux-wireless-owner@vger.kernel.org

On 03/18/2010 04:20 PM, Johannes Berg wrote:
> On Thu, 2010-03-18 at 16:10 -0500, Larry Finger wrote:
>> On 03/18/2010 03:53 PM, Johannes Berg wrote:
>>> On Thu, 2010-03-18 at 12:46 -0500, Larry Finger wrote:
>>>> Michael,
>>>>
>>>> I'm switching this discussion from the kernel Bugzilla to the lists.
>>>>
>>>> As you know, but I'm restating for anyone that has not read our previous
>>>> discussions, the b43 driver needs to be changed to handle some of the newer
>>>> devices do not have an on-board SPROM. It would be trivial to incorporate the
>>>> data except for the need to have a unique, reproducible MAC.
>>>
>>> Where does the data usually come from in these devices?
>>
>> It comes from the SPROM, which is missing in the devices in question. Broadcrap
>> wanted to save a few pennies.
> 
> Right, but they have to support getting the data somehow on for example
> windows even if there's no sprom. Do we know where it comes from then?

In the Linux driver and likely in the Windows driver, the SPROM data is read
from the SPROM and encoded into a set of tagged strings. After that, the actual
SPROM is ignored. I have not completed the RE on this area, but it looks as if
they have a set of "canned" data that is copied into the area. How they handle a
MAC is not yet understood.

Larry