On Thu, Dec 29, 2022 at 03:44:02PM +0100, Arnd Bergmann wrote:
> On Thu, Dec 29, 2022, at 10:57, Daehwan Jung wrote:
> > Currently, dwc3 invokes just xhci platform driver without any data.
> > We add xhci node as child of dwc3 node in order to get data from
> > device tree. It populates "xhci" child by name during initialization
> > of host. This patch only effects if dwc3 node has a child named "xhci"
> > not to disturb original path.
>
> Using child nodes is not the normal way of abstracting a soc specific
> variant of a device, though there are some USB host drivers that
> do this. Just use the node itself and add whatever samsung specific
> properties are needed based on the compatible string.
>
I've tried to use existing platform drivers(dwc3, xhci-plat).
Dwc3 has host mode and I think it's necessary to have child node.
Currently we can't use compatible string but can just use xhci platform driver
itself. That's why I modified to have a xhci child. It makes us to use
specific properties.
I don't find a better way even if it's not the normal way.
I'm going to talk with other maintainers(dwc3, xhci-plat) to solve the
problem.
> > @@ -86,6 +90,33 @@ static void xhci_plat_quirks(struct device *dev,
> > struct xhci_hcd *xhci)
> > xhci->quirks |= XHCI_PLAT | priv->quirks;
> > }
> >
> > +static int xhci_plat_bus_suspend(struct usb_hcd *hcd)
> > +{
> > + struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> > +
> > + if (xhci->quirks & XHCI_ROOTHUB_WAKEUP) {
> > + if (hcd == xhci->main_hcd)
> > + __pm_relax(xhci->main_wakelock);
> > + else
> > + __pm_relax(xhci->shared_wakelock);
> > + }
> > +
> > + return xhci_bus_suspend(hcd);
> > +}
> > +
> > +static int xhci_plat_bus_resume(struct usb_hcd *hcd)
> > +{
> > + struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> > +
> > + if (xhci->quirks & XHCI_ROOTHUB_WAKEUP) {
> > + if (hcd == xhci->main_hcd)
> > + __pm_stay_awake(xhci->main_wakelock);
> > + else
> > + __pm_stay_awake(xhci->shared_wakelock);
> > + }
> > + return xhci_bus_resume(hcd);
> > +}
>
> It looks like these are no longer tied to the Samsung
> device type, which would be a step in the right direction,
> but I think adding this should be a separate patch since
> it is not a hardware specific change but a new feature.
>
> Arnd
>
Thanks for the comment. I will separate and fix commit msg on next
submission.
Best Regards,
Jung Deahwan
