Re: [PATCH] usb: cdns3: Fixed incorrect gadget state

From: Peter Chen
Date: Mon Jun 28 2021 - 21:15:06 EST


On 21-06-28 03:46:38, Pawel Laszczak wrote:
> >
> >On 21-06-23 09:02:47, Pawel Laszczak wrote:
> >> From: Pawel Laszczak <pawell@xxxxxxxxxxx>
> >>
> >> For delayed status phase, the usb_gadget->state was set
> >> to USB_STATE_ADDRESS and it has never been updated to
> >> USB_STATE_CONFIGURED.
> >> Patch updates the gadget state to correct USB_STATE_CONFIGURED.
> >> As a result of this bug the controller was not able to enter to
> >> Test Mode while using MSC function.
> >
> >Pawel, would you please describe more about this issue? I remember the cdns3
> >controller at i.mx series SoC could enter test mode by using current
> >code.
>
> The issue occurs only for MSC class. MSC class has delayed status stage, so
> after returning from cdns3_req_ep0_set_configuration function called
> for Set Configuration driver remains in USB_STATE_ADDRESS.
>
> In order to enter to test mode driver needs meet the condition included in
> cdns3_ep0_feature_handle_device function:
> if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
> return -EINVAL;
>
> But it is still in USB_STATE_ADDRESS, because there was delayed status stage.
> To fix issue driver state must be updated to USB_STATE_CONFIGURED before
> or after finishing status stage.
>

I am wondering if the cdns3 driver set gadget state as USB_STATE_ADDRESS
is correct for delayed status stage, since the composite core has already
set it as USB_STATE_CONFIGURED at function set_config.

Peter
> >
> >>
> >> Cc: <stable@xxxxxxxxxxxxxxx>
> >> Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
> >> Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
> >> ---
> >> drivers/usb/cdns3/cdns3-ep0.c | 1 +
> >> 1 file changed, 1 insertion(+)
> >>
> >> diff --git a/drivers/usb/cdns3/cdns3-ep0.c b/drivers/usb/cdns3/cdns3-ep0.c
> >> index 9a17802275d5..ec5bfd8944c3 100644
> >> --- a/drivers/usb/cdns3/cdns3-ep0.c
> >> +++ b/drivers/usb/cdns3/cdns3-ep0.c
> >> @@ -731,6 +731,7 @@ static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
> >> request->actual = 0;
> >> priv_dev->status_completion_no_call = true;
> >> priv_dev->pending_status_request = request;
> >> + usb_gadget_set_state(&priv_dev->gadget, USB_STATE_CONFIGURED);
> >> spin_unlock_irqrestore(&priv_dev->lock, flags);
> >>
> >> /*
> >> --
> >> 2.25.1
> >>
> >
> --
>
> Thanks,
> Pawel Laszczak
>

--

Thanks,
Peter Chen