Re: [PATCH] usb: musb: Disable pullup in gadget setup

[Paul Cercueil]

Hi Bin,


Le mar. 30 avril 2019 à 11:05, Bin Liu <b-liu@xxxxxx> a écrit :
> Hi Paul,
>
> On Thu, Apr 04, 2019 at 11:10:46AM -0500, Bin Liu wrote:
> >  On Thu, Apr 04, 2019 at 11:37:43AM +0200, Paul Cercueil wrote:
> >  > The pullup may be already enabled before the driver is 
> > initialized.
> >  > It has to be disabled at init time, as we cannot guarantee that a 
> > gadget
> >  > driver will be bound to the UDC.
> >  >
> >  > Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> >  > ---
> >  >  drivers/usb/musb/musb_gadget.c | 1 +
> >  >  1 file changed, 1 insertion(+)
> >  >
> >  > diff --git a/drivers/usb/musb/musb_gadget.c 
> > b/drivers/usb/musb/musb_gadget.c
> >  > index ffe462a657b1..094dc59c834c 100644
> >  > --- a/drivers/usb/musb/musb_gadget.c
> >  > +++ b/drivers/usb/musb/musb_gadget.c
> >  > @@ -1794,6 +1794,7 @@ int musb_gadget_setup(struct musb *musb)
> >  >
> >  >  	musb->is_active = 0;
> >  >  	musb_platform_try_idle(musb, 0);
> >  > +	musb_pullup(musb, 0);
> >  >
> >  >  	status = usb_add_gadget_udc(musb->controller, &musb->g);
> >  >  	if (status)
> >
> >  Applied.
>
> Sorry, I have dropped this patch from my tree. I realized the gadget
> core already defines callbacks to control the pullup. I think the
> proper fix should be calling usb_udc_vbus_handler() in musb gadget or
> glue layers.
>
> -Bin.

usb_udc_vbus_handler() requires a usb_gadget *, I don't see where I can
get that from the struct musb.

Besides, the point is to have the pullup disabled before a gadget is 
bound,
so I don't understand why you suggest that?

-Paul