[PATCH v6 17/22] usb: dwc2: host: Manage frame nums better in scheduler

Herrero, Gregory gregory.herrero at intel.com
Tue Feb 9 01:53:41 PST 2016

Hi Doug,

> Hi,
> On Thu, Jan 28, 2016 at 6:20 PM, Douglas Anderson <dianders at chromium.org> wrote:
> >  static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
> >                          struct dwc2_hcd_urb *urb)
> >  {
> > @@ -569,11 +655,6 @@ static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
> >                               qh->ep_type == USB_ENDPOINT_XFER_ISOC,
> >                               bytecount));
> >
> > -               /* Ensure frame_number corresponds to the reality */
> > -               hsotg->frame_number = dwc2_hcd_get_frame_number(hsotg);
> In reviewing patches I realized that this is actually a revert of
> commit dd81dd7c8178 ("usb: dwc2: host: use correct frame number during
> qh init").  IMHO that patch was wrong: hsotg->frame_number is supposed
> to be the frame number as of the last start of frame.  If we need to
> know a more recent frame number then we should query it ourselves.
> Presumably the reason for the original patch was to try to fix some of
> the same problems I've addressed in my series, so I'd presume that
> this doesn't add any new regressions.  I haven't heard much from
> Gregory Herrero about my series, but it would be nice to confirm that
> this virtual revert wasn't causing problems.

This patch ("usb: dwc2: host: use correct frame number during qh init")
is no more needed with your patchset.
Note that your patchset is also reverting commit 08c4ffc:
("usb: dwc2: host: reset frame number after suspend")
but it is no more needed as well with your patchset.

I tried suspend/resume with different devices and didn't face the issue
my previous commit was fixing.


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