Problem with full speed devices on PowerPC MPC5121 host port

Alan Stern stern at
Sat Jan 7 05:03:07 EST 2012

On Fri, 6 Jan 2012, Matthias Fuchs wrote:

> For my eyes it does not really look like a general USB issue.
> It looks like a problem with the Freescale EHCI implementation that is
> influenced by high interrupt or internal bus load caused by the flood ping.

Indeed, it might be a problem with the built-in Transaction Translator.  
That would explain why it affect full-speed devices.

However, I would expect the resetting the controller hardware (which 
happens when you reload the ehci-fsl driver) would fix any such issues.  
It's hard to imagine how a problem could survive a reset like that.

Alan Stern

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