Re: [PATCH] usb: dwc3: gadget: giveback request if start transfer fail

[Felipe Balbi <balbi@ti.com>]

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Hi,

On Thu, May 01, 2014 at 02:36:08AM -0400, Zhuang Jin Can wrote:
> At least we should giveback the current request to the
> gadget. Otherwise, the gadget will be stuck without knowing
> anything.
> 
> It was oberved that the failure can happen if the request is
> queued when the run/stop bit of controller is not set.

why is your gadget queueing any requests before calling ->udc_start() ?

A better question, what modification have you done to udc-core.c which
broke this ? udc-core *always* calls ->udc_start() by the time you load
a gadget driver so this case will *never* happen. Whatever modification
you did, broke this assumption and I will *not* accept this patch
because the bug is elsewhere and *not* in mainline kernel.

> Signed-off-by: Zhuang Jin Can <jin.can.zhuang@intel.com>
> ---
>  drivers/usb/dwc3/gadget.c |    4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 70715ee..8d0c3c7 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -1000,9 +1000,7 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
>  		 * here and stop, unmap, free and del each of the linked
>  		 * requests instead of what we do now.
>  		 */
> -		usb_gadget_unmap_request(&dwc->gadget, &req->request,
> -				req->direction);
> -		list_del(&req->list);
> +		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
>  		return ret;
>  	}
>  
> -- 
> 1.7.9.5
> 

-- 
balbi

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