[PATCH v2 3/4] USB: EHCI: improve interrupt qh unlink

[oliver@neukum.org (Oliver Neukum)]

On Monday 24 June 2013 19:16:43 Ming Lei wrote:
> On Mon, Jun 24, 2013 at 6:28 PM, Oliver Neukum <oliver@neukum.org> wrote:
> > On Monday 24 June 2013 17:42:04 Ming Lei wrote:
> >> This patch improves this above situation, and the qh will wait for 5
> >> milliseconds before being unlinked from hardware, if one URB is submitted
> >> during the period, the qh is move out of unlink wait list and the
> >> interrupt transfer can be scheduled immediately, not like before: the
> >> transfer is only linked to hardware until previous unlink is completed.
> >
> > It seems to me that this logic should be used only if the URB completed
> > without error.
> 
> The current completed URB with error  doesn't mean the later submitted
> URB will complete with error, so I don't think the logic is related with URB
> completion error.

But

a) it is likelier
b) the driver will start error handling

And what about the bandwidth? At least if you unlink the URB, its bandwidth
should be given back immediately.

	Regards
		Oliver