Re: [PATCH] usb: hide usb_of_get_companion_dev for CONFIG_USB=n

From: Arnd Bergmann
Date: Mon Aug 20 2018 - 07:22:36 EST


On Mon, Aug 20, 2018 at 5:22 AM Yoshihiro Shimoda
<yoshihiro.shimoda.uh@xxxxxxxxxxx> wrote:
> > From: Arnd Bergmann, Sent: Tuesday, August 14, 2018 11:27 PM
> >
> > On Tue, Aug 14, 2018 at 3:58 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
> > > On Mon, 13 Aug 2018, Arnd Bergmann wrote:
> > > > diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
> > > > index 0a16cbd4e528..663a8bd67a7b 100644
> > > > --- a/drivers/usb/gadget/udc/Kconfig
> > > > +++ b/drivers/usb/gadget/udc/Kconfig
> > > > @@ -193,6 +193,7 @@ config USB_RENESAS_USB3
> > > > tristate 'Renesas USB3.0 Peripheral controller'
> > > > depends on ARCH_RENESAS || COMPILE_TEST
> > > > depends on EXTCON
> > > > + depends on USB || !USB
> > >
> > > Is this some weird standard idiom? It looks really strange.
> >
> > Yes, and yes.
> >
> > A less common way to write it is
> >
> > depends on (USB != m) || m
> >
> > which some people prefer, but I find even weirder.
>
> Thank you for the patch!
>
> On other thread, John mentions gadget-side drivers should not depend on host-side [1].
> So, I submitted a patch today [2]. What do you think about my submitted patch?
>
> [1]
> https://marc.info/?l=linux-usb&m=153433776202861&w=2

I don't really think this is a big issue, as you can still build the driver
with CONFIG_USB=n, so it's not a strict dependency.

> [2]
> https://patchwork.kernel.org/patch/10569847/

On the other hand, your patch looks nice and is somewhat
less confusing, so you have my Ack on that.

Arnd