Re: [PATCH] usb: cdnsp: Fixes issue with Configure Endpoint command

From: Peter Chen
Date: Fri Apr 02 2021 - 19:57:37 EST


On 21-03-30 04:26:10, Pawel Laszczak wrote:
> Hi Peter,
>
> >
> >On 21-03-22 07:09:02, Pawel Laszczak wrote:
> >> From: Pawel Laszczak <pawell@xxxxxxxxxxx>
> >>
> >> Patch adds flag EP_UNCONFIGURED to detect whether endpoint was
> >> unconfigured. This flag is set in cdnsp_reset_device after Reset Device
> >> command. Among others this command disables all non control endpoints.
> >> Flag is used in cdnsp_gadget_ep_disable to protect controller against
> >> invoking Configure Endpoint command on disabled endpoint. Lack of this
> >> protection in some cases caused that Configure Endpoint command completed
> >> with Context State Error code completion.
> >>
> >> Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
> >> Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
> >> ---
> >> drivers/usb/cdns3/cdnsp-gadget.c | 18 +++++++++++++-----
> >> drivers/usb/cdns3/cdnsp-gadget.h | 11 ++++++-----
> >> 2 files changed, 19 insertions(+), 10 deletions(-)
> >>
> >> diff --git a/drivers/usb/cdns3/cdnsp-gadget.c b/drivers/usb/cdns3/cdnsp-gadget.c
> >> index d7d4bdd57f46..de17cc4ad91a 100644
> >> --- a/drivers/usb/cdns3/cdnsp-gadget.c
> >> +++ b/drivers/usb/cdns3/cdnsp-gadget.c
> >> @@ -727,7 +727,7 @@ int cdnsp_reset_device(struct cdnsp_device *pdev)
> >> * are in Disabled state.
> >> */
> >> for (i = 1; i < CDNSP_ENDPOINTS_NUM; ++i)
> >> - pdev->eps[i].ep_state |= EP_STOPPED;
> >> + pdev->eps[i].ep_state |= EP_STOPPED | EP_UNCONFIGURED;
> >>
> >> trace_cdnsp_handle_cmd_reset_dev(slot_ctx);
> >>
> >> @@ -942,6 +942,7 @@ static int cdnsp_gadget_ep_enable(struct usb_ep *ep,
> >>
> >> pep = to_cdnsp_ep(ep);
> >> pdev = pep->pdev;
> >> + pep->ep_state &= ~EP_UNCONFIGURED;
> >>
> >> if (dev_WARN_ONCE(pdev->dev, pep->ep_state & EP_ENABLED,
> >> "%s is already enabled\n", pep->name))
> >> @@ -1023,9 +1024,13 @@ static int cdnsp_gadget_ep_disable(struct usb_ep *ep)
> >> goto finish;
> >> }
> >>
> >> - cdnsp_cmd_stop_ep(pdev, pep);
> >> pep->ep_state |= EP_DIS_IN_RROGRESS;
> >> - cdnsp_cmd_flush_ep(pdev, pep);
> >> +
> >> + /* Endpoint was unconfigured by Reset Device command. */
> >> + if (!(pep->ep_state & EP_UNCONFIGURED)) {
> >> + cdnsp_cmd_stop_ep(pdev, pep);
> >> + cdnsp_cmd_flush_ep(pdev, pep);
> >> + }
> >>
> >> /* Remove all queued USB requests. */
> >> while (!list_empty(&pep->pending_list)) {
> >> @@ -1036,6 +1041,7 @@ static int cdnsp_gadget_ep_disable(struct usb_ep *ep)
> >> cdnsp_invalidate_ep_events(pdev, pep);
> >>
> >> pep->ep_state &= ~EP_DIS_IN_RROGRESS;
> >> +
> >
> >Useless blank line
> >
> >> drop_flag = cdnsp_get_endpoint_flag(pep->endpoint.desc);
> >> ctrl_ctx = cdnsp_get_input_control_ctx(&pdev->in_ctx);
> >> ctrl_ctx->drop_flags = cpu_to_le32(drop_flag);
> >> @@ -1043,10 +1049,12 @@ static int cdnsp_gadget_ep_disable(struct usb_ep *ep)
> >>
> >> cdnsp_endpoint_zero(pdev, pep);
> >>
> >> - ret = cdnsp_update_eps_configuration(pdev, pep);
> >> + if (!(pep->ep_state & EP_UNCONFIGURED))
> >> + ret = cdnsp_update_eps_configuration(pdev, pep);
> >> +
> >> cdnsp_free_endpoint_rings(pdev, pep);
> >>
> >> - pep->ep_state &= ~EP_ENABLED;
> >> + pep->ep_state &= ~(EP_ENABLED | EP_UNCONFIGURED);
> >> pep->ep_state |= EP_STOPPED;
> >>
> >> finish:
> >> diff --git a/drivers/usb/cdns3/cdnsp-gadget.h b/drivers/usb/cdns3/cdnsp-gadget.h
> >> index 6bbb26548c04..e628bd539e23 100644
> >> --- a/drivers/usb/cdns3/cdnsp-gadget.h
> >> +++ b/drivers/usb/cdns3/cdnsp-gadget.h
> >> @@ -830,11 +830,12 @@ struct cdnsp_ep {
> >> unsigned int ep_state;
> >> #define EP_ENABLED BIT(0)
> >> #define EP_DIS_IN_RROGRESS BIT(1)
> >> -#define EP_HALTED BIT(2)
> >> -#define EP_STOPPED BIT(3)
> >> -#define EP_WEDGE BIT(4)
> >> -#define EP0_HALTED_STATUS BIT(5)
> >> -#define EP_HAS_STREAMS BIT(6)
> >> +#define EP_UNCONFIGURED BIT(2)
> >
> >Why add new flag as BIT(2), it causes many changes in this patch?
>
> In my feeling, EP_UNCONFIGURED is more associates with the first 2 flags, so I've decided
> put it after BIT(1).

No, you may not add such relationship, each flag has its own meaning,
otherwise, the sequence of flag bitmap may be changed again.

Peter

>
> >
> >> +#define EP_HALTED BIT(3)
> >> +#define EP_STOPPED BIT(4)
> >> +#define EP_WEDGE BIT(5)
> >> +#define EP0_HALTED_STATUS BIT(6)
> >> +#define EP_HAS_STREAMS BIT(7)
> >>
> >> bool skip;
> >> };
> >> --
> >> 2.25.1
> >>
> >
> >--
> >
> >Thanks,
> >Peter Chen
>

--

Thanks,
Peter Chen