On Mon, 27 Jun 2005, Dag Nygren wrote:

> Hi again,
> 
> remember me with the USB memory problems?
> 
> Anyway I studied a little of the USB specs and have a question:
> 
> All the problems seems to occur after a report back from the
> USB controller with the cc register set at 6. This means that
> the controller detected a PID check error. If I read the specs right
> this transfer should then be retried (by the USB layer I presume)
> and not reported back as failed to upper layers. Am I right?

I'm not very familiar with the OHCI spec, but if you're seeing a PID check 
error then probably the transfer _was_ retried already (by the hardware).  
It has to be reported as failed to the upper layers if the PID check 
occurs every time the transfer is retried.

> Additionally there really seems to be (as you pointed out) problems
> in the whole SCSI (and possibly USB) layer in the way it handles
> error conditions.

There definitely are some bugs in the SCSI layer.  They are being worked 
on.

Alan Stern



-------------------------------------------------------
SF.Net email is sponsored by: Discover Easy Linux Migration Strategies
from IBM. Find simple to follow Roadmaps, straightforward articles,
informative Webcasts and more! Get everything you need to get up to
speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel

Reply via email to