Re: [PATCH v9 27/28] media: iris: enable video driver probe of SM8250 SoC

From: Johan Hovold
Date: Tue Feb 04 2025 - 04:52:57 EST


On Mon, Feb 03, 2025 at 05:37:28PM +0200, Dmitry Baryshkov wrote:
> On Mon, Feb 03, 2025 at 09:39:00AM +0100, Johan Hovold wrote:
> > On Fri, Jan 10, 2025 at 08:01:21PM +0200, Dmitry Baryshkov wrote:

> > > Also as venus and iris drivers are not completely
> > > equivalent wrt supported platforms, distributions will have to select
> > > whether to disable support for older platforms or for new platforms:
> > > Kconfig dependency will make it impossible to enable support for both
> > > kinds.
> >
> > You shouldn't have both enabled. The only reason for keeping support
> > for the same hardware in both drivers is that the iris support is
> > incomplete and considered experimental. No one should enable that except
> > for development and evaluation purposes until the driver is up to par.
> > And then you drop support from the old driver along with the config
> > option.
>
> That's the plan. This modparam is a temporal thing for transition
> period. And yes, as a developers / platform enablers we want to be able
> to have a quick turnaround between drivers.
>
> Please stop forcing your decisions on other people. The Linux kernel and
> its development process has always been about providing a possibility,
> not a policy.

That's just not true. The rule is to not have two drivers for the same
hardware (even if we very rarely have accepted some well-motivated
exceptions).

I understand that you may have an unorthodox view of this as you work on
the MSM DRM driver, but hiding incomplete and broken code behind module
parameters so that you can game the upstreaming process (e.g. like you
did for the eDP PSR feature) is simply not a model that anyone should
follow.

Johan