[pvrusb2] New driver snapshot: pvrusb2-mci-20060318

[Mike Isely]

On Tue, 21 Mar 2006, Hans Verkuil wrote:

>>>> On Sunday 19 March 2006 00:33, Mike Isely wrote:
>>>
>> Hans points out that there are firmware images floating around that are 
>> greater than 256KB, though the data beyond 256KB apparently is 
>> meaningless drivel.  The only effect from this is that now I get to 
>> loosen up the sanity check.  Hans: Is it at least safe to check that 
>> the image size is *at least* 256KB?  Personally I don't understand why 
>> these firmware images with garbage appended aren't just "fixed".
>
> They should be minimal 256 KB. The extra size is *mostly* zeroes, but not
> all. I've no idea if Hauppauge is also loading the extra bytes or not (I
> should be able to check this). It may be relevant. Who knows?
>
>            Hans

Well I can tell you positively that for the PVR USB2 devices, only 256KB 
gets loaded by the Windows driver.  I know this because the technique used 
to generate a signature for fwextract.pl uses usbsnoop output from the 
Windows side - so we know exactly what and how much was loaded to the 
encoder.

I still haven't heard any reason for why these files have garbage 
appended.  Could this be something lost to history where the firmware 
image had been generated long ago by some utility which couldn't know how 
much data to extract?  I have no idea, but I'd be interested in 
understanding this so it can be dealt with correctly rather than 
perpetuated forward.

   -Mike

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