On Thu, Apr 21, 2022 at 07:22:50PM -0700, Thinh Nguyen wrote:
> Since we can't guarantee that the host won't send new Setup packet
> before going through the device-initiated disconnect, don't prepare
> beyond the Setup stage and keep the device in EP0_SETUP_PHASE. This
> ensures that the device-initated disconnect sequence can go through
> gracefully. Note that the controller won't service the End Transfer
> command if it can't DMA out the Setup packet.
>
> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
> ---
> drivers/usb/dwc3/ep0.c | 2 +-
> drivers/usb/dwc3/gadget.c | 29 +++++++++++++++++------------
> 2 files changed, 18 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
> index 1064be5518f6..c47c696316dd 100644
> --- a/drivers/usb/dwc3/ep0.c
> +++ b/drivers/usb/dwc3/ep0.c
> @@ -813,7 +813,7 @@ static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
> int ret = -EINVAL;
> u32 len;
>
> - if (!dwc->gadget_driver)
> + if (!dwc->gadget_driver || !dwc->connected)
> goto out;
>
> trace_dwc3_ctrl_req(ctrl);
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index a86225dbaa2c..e5f07c0e8ad9 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2505,6 +2505,23 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
> spin_lock_irqsave(&dwc->lock, flags);
> dwc->connected = false;
>
> + /*
> + * Per databook, when we want to stop the gadget, if a control transfer
> + * is still in process, complete it and get the core into setup phase.
> + */
> + if (dwc->ep0state != EP0_SETUP_PHASE) {
> + int ret;
> +
> + reinit_completion(&dwc->ep0_in_setup);
> +
> + spin_unlock_irqrestore(&dwc->lock, flags);
> + ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
> + msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
> + spin_lock_irqsave(&dwc->lock, flags);
> + if (ret == 0)
> + dev_warn(dwc->dev, "timed out waiting for SETUP phase\n");
DWC3_PULL_UP_TIMEOUT is 500 msec. If the ongoing control transfer is delayed
(dwc3::delayed_status), for whatever reason, would there be a problem?
Thanks,
Pavan
