On Wed, Feb 07, 2018 at 03:43:23PM +0200, Mathias Nyman wrote:
> On 07.02.2018 11:45, Peter Chen wrote:
> >Hi Mathias,
> >
> >I am implementing USB2 EHSET SINGLE_STEP_SET_FEATURE Test for XHCI port,
> >(see ehset_single_step_set_feature for EHCI), it needs to set IOC
> >for setup packet, and software waits 15 seconds before DATA + STATUS stage.
> >After porting such design for XHCI, it triggers above warning, and
> >returns -ESHUTDOWN for URB. Any reasons why we don't allow completion
> >interrupt for SETUP stage? Thanks.
> >
>
> Current xhci driver control transfer implementation doesn't support
> queuing a control transfer in parts. we set the IOC only for the status
> stage, and we always queue a status stage (and possibly data stage) automatically
> when queuing a control transfer URB.
>
> If we get a success event for the SETUP stage the driver will finish the TD and
> return the whole URB.
>
> For testing purposes you would need to make sure we don't call finish_td() for
> a success event at the SETUP stage, something like this (untested):
>
> diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
> index c5cbc68..f6d005e 100644
> --- a/drivers/usb/host/xhci-ring.c
> +++ b/drivers/usb/host/xhci-ring.c
> @@ -2014,12 +2014,8 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
> switch (trb_comp_code) {
> case COMP_SUCCESS:
> - if (trb_type != TRB_STATUS) {
> - xhci_warn(xhci, "WARN: Success on ctrl %s TRB without IOC set?\n",
> - (trb_type == TRB_DATA) ? "data" : "setup");
> - *status = -ESHUTDOWN;
> - break;
> - }
> + if (trb_type == TRB_SETUP)
> + return 0;
> *status = 0;
> break;
> case COMP_SHORT_PACKET:
>
Thanks, Mathias. I need to call finish_td since it needs to
giveback and cleanup URB. And I see below code at process_ctrl_td,
why we can't call it? In fact, I only see warning message, but
without any errors for transactions. How about only delete message
or change debug level as xhci_dbg?
/* stopped at setup stage, no data transferred */
if (trb_type == TRB_SETUP)
goto finish_td;
--
Best Regards,
Peter Chen
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