From: vichy
> hi all:
> when i trace xhci source, I found in skip_isoc_td, there is a
> possibility to increase de-queue pointer twice.
>
> in skip_isoc_td:
> /* Update ring dequeue pointer */
> while (ep_ring->dequeue != td->last_trb)
> inc_deq(xhci, ep_ring);
> inc_deq(xhci, ep_ring);
>
> why (ep_ring->dequeue != td->last_trb) we have to increase the dequeue
> pointer?
> I try to find any description in spec about this but in vain.
> is there any special reason to do so?
An isoc transfer can consist of a lot of TRB.
The code wants to skip all of them.
I suspect there are faster ways to achieve the same effect!
David
