On Tue, Feb 28, 2023, Jack Pham wrote:
> On Tue, Feb 28, 2023 at 12:24:18PM -0800, Wesley Cheng wrote:
> > Previously, there was a 100uS delay inserted after issuing an end transfer
> > command for specific controller revisions. This was due to the fact that
> > there was a GUCTL2 bit field which enabled synchronous completion of the
> > end transfer command once the CMDACT bit was cleared in the DEPCMD
> > register. Since this bit does not exist for all controller revisions, add
> > the delay back in, and increase the duration to 1ms for the controller to
> > complete the command.
> >
> > An issue was seen where the USB request buffer was unmapped while the DWC3
> > controller was still accessing the TRB. However, it was confirmed that the
> > end transfer command was successfully submitted. (no end transfer timeout)
> > In situations, such as dwc3_gadget_soft_disconnect() and
> > __dwc3_gadget_ep_disable(), the dwc3_remove_request() is utilized, which
> > will issue the end transfer command, and follow up with
> > dwc3_gadget_giveback(). At least for the USB ep disable path, it is
> > required for any pending and started requests to be completed and returned
> > to the function driver in the same context of the disable call. Without
> > the GUCTL2 bit, it is not ensured that the end transfer is completed before
> > the buffers are unmapped.
> >
> > Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
> > ---
> > Changes in v3:
> > - Fixed subject title and modified commit text to reference the new 1ms
> > delay
> >
> > Changes in v2:
> > - Increase delay value to 1ms
> > - Make this applicable to DWC32 revisions as well
> >
> > drivers/usb/dwc3/gadget.c | 15 ++++++++++++---
> > 1 file changed, 12 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > index 3c63fa97a680..15adf07a4df4 100644
> > --- a/drivers/usb/dwc3/gadget.c
> > +++ b/drivers/usb/dwc3/gadget.c
> > @@ -1699,6 +1699,7 @@ static int __dwc3_gadget_get_frame(struct dwc3 *dwc)
> > */
> > static int __dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force, bool interrupt)
> > {
> > + struct dwc3 *dwc = dep->dwc;
> > struct dwc3_gadget_ep_cmd_params params;
> > u32 cmd;
> > int ret;
> > @@ -1722,10 +1723,14 @@ static int __dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force, bool int
> > WARN_ON_ONCE(ret);
> > dep->resource_index = 0;
> >
> > - if (!interrupt)
> > + if (!interrupt) {
> > + if (DWC3_IP_IS(DWC32) || DWC3_IP_IS(DWC31) ||
> > + DWC3_VER_IS_PRIOR(DWC3, 310A))
>
> How about a little more succinctly:
>
> if (!DWC3_IP_IS(DWC3) || DWC3_VER_IS_PRIOR(DWC3, 310A))
> ?
>
or this:
if (!DWC3_VER_IS_WITHIN(DWC3, 310A, ANY))
BR,
Thinh
