Re: [PATCH] usb: cdns3: gadget: Don't manage pullups

[Roger Quadros]

Peter,

On 25/10/2019 06:13, Peter Chen wrote:
> On 19-10-23 09:17:45, Pawel Laszczak wrote:
> > Hi,
> >
> > Reviewed-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
>
> Hi Roger & Pawel,
>
> Assume gadget function has already enabled, if you switch host mode
> to device mode, with your changes, where the device mode will be enabled
> again?

When it switches from device mode to host the UDC is removed. When we switch
back from host to device mode the UDC is added, so,

usb_add_gadget_udc_release()-> check_pending_gadget_drivers()->
udc_bind_to_driver()->usb_udc_connect_control()->usb_gadget_connect()->
gadget->ops->pullup()

cheers,
-roger
> Peter
> > Regards,
> > Pawel,
> >
> > > The USB gadget core is supposed to manage pullups
> > > of the controller. Don't manage pullups from within
> > > the controller driver. Otherwise, function drivers
> > > are not able to keep the controller disconnected from
> > > the bus till they are ready. (e.g. g_webcam)
> > >
> > > Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> > > ---
> > > Hi Greg/Felipe,
> > >
> > > This can be used for -rc as it is a bug fix.
> > >
> > > cheers,
> > > -roger
> > >
> > > drivers/usb/cdns3/gadget.c | 4 ----
> > > 1 file changed, 4 deletions(-)
> > >
> > > diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
> > > index 2ca280f4c054..714382d96055 100644
> > > --- a/drivers/usb/cdns3/gadget.c
> > > +++ b/drivers/usb/cdns3/gadget.c
> > > @@ -2324,8 +2324,6 @@ static void cdns3_gadget_config(struct cdns3_device *priv_dev)
> > > 	writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
> > >
> > > 	cdns3_configure_dmult(priv_dev, NULL);
> > > -
> > > -	cdns3_gadget_pullup(&priv_dev->gadget, 1);
> > > }
> > >
> > > /**
> > > @@ -2708,8 +2706,6 @@ static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup)
> > > 	/* disable interrupt for device */
> > > 	writel(0, &priv_dev->regs->usb_ien);
> > >
> > > -	cdns3_gadget_pullup(&priv_dev->gadget, 0);
> > > -
> > > 	return 0;
> > > }
> > >
> > > --
> > > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> > > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

--
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki