Re: [PATCH] usb: dwc3: gadget: Restart DWC3 gadget when enabling pullup

[Michael Tretter <m.tretter@pengutronix.de>]

On Fri, 20 Nov 2020 16:08:04 +0100, Michael Tretter wrote:
> On Thu, 19 Nov 2020 16:13:21 -0800, Wesley Cheng wrote:
> > usb_gadget_deactivate/usb_gadget_activate does not execute the UDC start
> > operation, which may leave EP0 disabled and event IRQs disabled when
> > re-activating the function. Move the enabling/disabling of USB EP0 and
> > device event IRQs to be performed in the pullup routine.
> > 
> > Fixes: ae7e86108b12 ("usb: dwc3: Stop active transfers before halting the
> > controller")
> > 
> > Reported-by: Michael Tretter <m.tretter@pengutronix.de>
> > Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
> 
> Tested-by: Michael Tretter <m.tretter@pengutronix.de>

Gentle ping. I didn't see this fix being picked up into any of the usb trees.

Michael

> 
> > ---
> >  drivers/usb/dwc3/gadget.c | 14 +++-----------
> >  1 file changed, 3 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > index 5d879b7606d5..922c8b76e534 100644
> > --- a/drivers/usb/dwc3/gadget.c
> > +++ b/drivers/usb/dwc3/gadget.c
> > @@ -1988,6 +1988,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
> >  
> >  static void dwc3_gadget_disable_irq(struct dwc3 *dwc);
> >  static void __dwc3_gadget_stop(struct dwc3 *dwc);
> > +static int __dwc3_gadget_start(struct dwc3 *dwc);
> >  
> >  static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> >  {
> > @@ -2050,6 +2051,8 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> >  			dwc->ev_buf->lpos = (dwc->ev_buf->lpos + count) %
> >  						dwc->ev_buf->length;
> >  		}
> > +	} else {
> > +		__dwc3_gadget_start(dwc);
> >  	}
> >  
> >  	ret = dwc3_gadget_run_stop(dwc, is_on, false);
> > @@ -2224,10 +2227,6 @@ static int dwc3_gadget_start(struct usb_gadget *g,
> >  	}
> >  
> >  	dwc->gadget_driver	= driver;
> > -
> > -	if (pm_runtime_active(dwc->dev))
> > -		__dwc3_gadget_start(dwc);
> > -
> >  	spin_unlock_irqrestore(&dwc->lock, flags);
> >  
> >  	return 0;
> > @@ -2253,13 +2252,6 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
> >  	unsigned long		flags;
> >  
> >  	spin_lock_irqsave(&dwc->lock, flags);
> > -
> > -	if (pm_runtime_suspended(dwc->dev))
> > -		goto out;
> > -
> > -	__dwc3_gadget_stop(dwc);
> > -
> > -out:
> >  	dwc->gadget_driver	= NULL;
> >  	spin_unlock_irqrestore(&dwc->lock, flags);
> >  
> > -- 
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> > a Linux Foundation Collaborative Project
> > 
> > 
>