Re: [PATCH] drm/bridge: fix RC_CORE dependency

From: Arnd Bergmann <arnd@arndb.de>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: "Andrzej Hajda" <a.hajda@samsung.com>,
	"David Airlie" <airlied@linux.ie>,
	"Daniel Vetter" <daniel@ffwll.ch>,
	"Ronald Tschalär" <ronald@innovation.ch>,
	"Laurent Pinchart" <Laurent.pinchart@ideasonboard.com>,
	"Sean Paul" <sean@poorly.run>,
	dri-devel <dri-devel@lists.freedesktop.org>,
	"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] drm/bridge: fix RC_CORE dependency
Date: Thu, 18 Jul 2019 17:27:18 +0200	[thread overview]
Message-ID: <CAK8P3a2O9jaV=EfCLp=_X1wW6yAB9_cSGfMUBwFHjS+1x76yPg@mail.gmail.com> (raw)
In-Reply-To: <CAKdAkRS0w3KM-F95-F1jUicq2srAzWu21_7Npnw28F5fF+UxtA@mail.gmail.com>

On Thu, Jul 18, 2019 at 5:17 PM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> On Thu, Jul 18, 2019 at 6:13 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > On Thu, Jul 18, 2019 at 4:56 PM Andrzej Hajda <a.hajda@samsung.com> wrote:
> > > On 18.07.2019 16:21, Arnd Bergmann wrote:
> > > > On Thu, Jul 18, 2019 at 4:16 PM Andrzej Hajda <a.hajda@samsung.com> wrote:
> > > >> Proper solution has been already merged via input tree[1].
> > > >>
> > > >>
> > > >> [1]:
> > > >> https://lore.kernel.org/lkml/CAKdAkRTGXNbUsuKASNGLfwUwC7Asod9K5baYLPWPU7EX-42-yA@mail.gmail.com/
> > > > At that link, I only see the patch that caused the regression, not
> > > > the solution. Are you sure it's fixed?
> > >
> > >
> > > Ups, you are right, I though you are fixing what this patch attempted to
> > > fix :)
> > >
> > > Anyway, we want to avoid dependency on RC_CORE - this driver does not
> > > require it, but with RC_CORE it has additional features.
> >
> > Right, that's what my patch does: if RC_CORE is disabled, you can
> > still set DRM_SIL_SII8620=y, but if RC_CORE=m, DRM_SIL_SII8620
> > can only be =m or =n.
> >
> > > Maybe "imply INPUT" would help?
> >
> > No, that would make it worse. Device drivers really have no business
> > turning on other subsystems.
> >
>
> OK, in the meantime I will redo the branch by dropping the
> sil-sii8620.c Kconfig changes and also drop all "imply" business from
> applespi driver as they give us more trouble than they are worth. We
> do not have "imply" for i801_smbus for Symaptics SMBUS mode and it
> works fine. It it distro's task to configure the kernel properly.

Thanks!

I think the "drm/bridge: make remote control optional" patch is
fine with my fixup, the IS_ENABLED() checks take care of the
case where RC_CORE is unavailable, and the 'depends on
RC_CORE || !RC_CORE' line takes care of the RC_CORE=m
case.

I suppose Ronald could send a replacement patch with my
fixup after the merge window.

      Arnd