On 25.2.2025 13.57, Michal Pecio wrote:
I was looking at all uses of enqueue/dequeue pointers and I found two rather complex loops which appear to be doing really simple things. I don't understand why they were written this way, it seems wasteful and I see nothing that should go wrong if they are replaced with much simpler code. I rewrote them and the driver still works. I exercised Set TR Dequeue code by starting/stopping isoc streams, using usb-storage with crappy cable (transaction errors, halts) and also the smartctl -x trick that results in URB unlinks (both on usb-storage and uas) with some disks. The third patch is a dedupe. BTW, that comment there about section 6.4.4.1 of the 0.95 spec seems to be wrong, I suspect it should say that the chain bit cannot be *cleared* because that's how the code works and what some commit messages say. But I don't have 0.95 spec. New in v2: - dropped the patch for obsolete update_ring_for_set_deq_completion() - added a patch to enable the link chain quirk on one more HC - don't touch the chain bit in inc_enq_past_link() on quirky HCs - don't call inc_enq_past_link() unnecessarily Michal Pecio (3): usb: xhci: Apply the link chain quirk on NEC isoc endpoints usb: xhci: Simplify moving HW Dequeue Pointer past cancelled TDs usb: xhci: Unify duplicate inc_enq() code
Thanks, adding Patch 1/3 and 3/3, skipping 2/3 for now. -Mathias
