Re: [PATCH v5 1/3] xhci: hub: export symbol on xhci_hub_control

From: Thierry Reding
Date: Fri Oct 28 2022 - 05:53:00 EST


On Fri, Oct 28, 2022 at 08:04:54AM +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
> On Fri, Oct 28, 2022 at 05:36:41AM +0000, Jim Lin wrote:
> > On Thu, 2022-10-27 at 15:58 +0200, Greg KH wrote:
> > > External email: Use caution opening links or attachments
> > >
> > >
> > > On Thu, Oct 27, 2022 at 09:31:25PM +0800, Jim Lin wrote:
> > > > Add EXPORT_SYMBOL_GPL on xhci_hub_control() for other driver module
> > > > to invoke and avoid linking error.
> > >
> > > What other driver module?
> > >
> > > There is no user here :(
> > >
> > > confused,
> > >
> >
> > In arch/arm/configs/multi_v7_defconfig
> > It defines
> > CONFIG_USB_XHCI_TEGRA=m
> >
> > If I don't add EXPORT_SYMBOL_GPL on xhci_hub_control()
> > , I will get compile/linking error like
> >
> > ERROR: modpost: "xhci_hub_control" [drivers/usb/host/xhci-tegra.ko]
> > undefined!
> >
> > if patch
> > "[PATCH v5,3/3] xhci: tegra: USB2 pad power controls"
> >
> > https://patchwork.kernel.org/project/linux-usb/patch/20221027133127.27592-4-jilin@xxxxxxxxxx/
> > is added in xhci-tegra.c to invoke xhci_hub_control()
> >
> > Should I integrate this patch with [PATCH v5,3/3] as one?
>
> Yes, do not add something that is not needed for that specific commit,
> otherwise it causes reviewers to be confused.

Other subsystem maintainers prefer core changes to be split from driver
changes, so this type of split is commonly encountered elsewhere.

Obviously, since this is your turf you get to make the rules. I'm just
trying to say that this kind of advice can be confusing for contributors
because when they then sent driver and code changes mixed for their next
submission, the subsystem maintainer might tell them otherwise.

Thierry

Attachment: signature.asc
Description: PGP signature