Hey, Matt

While you're at it, could you have a look at PR kern/46176 ? =)

At least would you tell me if you have the same problem with your
device(s)

On Thu, 2002-12-19 at 11:32, Matthew Dillon wrote:
>     It took a hellofalong time pulling my hair out trying to figure out
>     why the Sony disk-on-key I just bought didn't work.
> 
>     First I added a Quirk entry for the standard 6-byte problem, but it
>     didn't solve the problem.
> 
>     Finally, after slogging through an insane amount of debugging (I mean,
>     it really generates a lot of debugging if you turn it all on!) I came
>     up with the following patch.  It appears that when an error occurs
>     and the umass device tries to read the sense data that it fails
>     comparing:
> 
>       sc->transfer_datalen - sc->transfer_actlen != UGETDW(sc->csw.dCSWDataResidue).
> 
>     As far as I can sc->transfer_actlen is NEVER updated.  It is always 0, so
>     I don't quite see how the calculation could ever possibly be correct
>     if DataResidue is what I think it is (a count-down of the number of 
>     unused bytes after a transfer).
> 
>     Note that my other UMASS device, a compact flash reader, has always
>     worked fine with just the Quirk entry.  I really need a USB expert to
>     tell me what is going on :-) 
> 
>     With the patch below my Sony diskkey works.  Note that the junk at the
>     end of the patch is debugging.  I noticed that the CAM layer thought
>     the READCAPACITY command succeeded when it didn't, and it was generating
>     weird sector-size errors due to the malloc'd return buffer containing
>     garbage.   I had to put real values in the buffer to catch the problem
>     consistently.  I don't know why the UMASS layer was returning a 
>     success code to CAM for failed READCAPACITY commands but it took an
>     hour just to figure that CAM was using garbage in the return buffer.
> 
>     USB Experts gravitate here!  Tell me I'm right or explain to me why I'm
>     wrong, because this stuff is incredibly complex and I'm having problems
>     thinking straight at 2:30 a.m. :-)
> 
>                                               -Matt
> 

-- 
Frode Nordahl <[EMAIL PROTECTED]>


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