Re: [PATCH 4/5] usb: dwc3: Allow end transfer commands to be sent during soft disconnect

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

On 7/8/2022, Wesley Cheng wrote:
> If soft disconnect is in progress, allow the endxfer command to be sent,
> without this, there is an issue where the stop active transfer call
> (during pullup disable) wouldn't actually issue the endxfer command,
> while clearing the DEP flag.
>
> In addition, if the DWC3_EP_DELAY_STOP flag was set before soft disconnect
> started (i.e. from the dequeue path), ensure that when the EP0 transaction
> completes during soft disconnect, to issue the endxfer with the force
> parameter set, as it does not expect a command complete event.
>
> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
> ---
>   drivers/usb/dwc3/ep0.c    | 3 +--
>   drivers/usb/dwc3/gadget.c | 5 ++++-
>   2 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
> index 506ef717fdc0..5851b0e9db0a 100644
> --- a/drivers/usb/dwc3/ep0.c
> +++ b/drivers/usb/dwc3/ep0.c
> @@ -290,8 +290,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
>   		if (!(dwc3_ep->flags & DWC3_EP_DELAY_STOP))
>   			continue;
>   
> -		dwc3_ep->flags &= ~DWC3_EP_DELAY_STOP;
> -		dwc3_stop_active_transfer(dwc3_ep, true, true);
> +		dwc3_stop_active_transfer(dwc3_ep, true, dwc->connected);
>   	}
>   }
>   
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index bd40608b19df..fba2797ad9ae 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -3696,8 +3696,10 @@ void dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force,
>   	if (dep->number <= 1 && dwc->ep0state != EP0_DATA_PHASE)
>   		return;
>   
> +	if (interrupt && (dep->flags & DWC3_EP_DELAY_STOP))
> +		return;
> +
>   	if (!(dep->flags & DWC3_EP_TRANSFER_STARTED) ||
> -	    (dep->flags & DWC3_EP_DELAY_STOP) ||
>   	    (dep->flags & DWC3_EP_END_TRANSFER_PENDING))
>   		return;
>   
> @@ -3744,6 +3746,7 @@ void dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force,
>   	__dwc3_stop_active_transfer(dep, force, interrupt);
>   	spin_lock(&dwc->lock);
>   
> +	dep->flags &= ~DWC3_EP_DELAY_STOP;

Can we clear this flag in __dwc3_stop_active_transfer(). It should apply 
if End Transfer command was sent.

Thanks,
Thinh

>   }
>   
>   static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)