Re: [PATCH 1/2] drm/input_helper: Add new input-handling helper

From: Brian Norris
Date: Wed Nov 17 2021 - 13:45:12 EST


On Fri, Nov 12, 2021 at 4:52 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:

(Snip other comments; they seem reasonable, and I'll factor them into
the next version)

> I guess one random thought I had is whether there would be an
> appropriate place to put this that _wasn't_ in DRM. I still wonder
> whether we'll ever try to upstream something like the cpufreq boost
> driver that we're carrying around and using in Chrome OS. If so, it
> would want to use these same helpers and it'd be pretty awkward for it
> to have to reach into DRM. ...any chance we could just land these
> helpers somewhere more generic?

Yeah, I was torn on what to do here as well. I'd rather land something
than nothing, and when reading past conversations, it sounded like
Dmitry didn't want this kind of thing in drivers/input/ [1]. I'd love
to be wrong here though.

I'm not sure where else this would belong though -- either in the
producing subsystem (input) or the consuming one(s) (drm, cpufreq). We
could make up some odd middle ground I suppose (lib/?), but that seems
pretty artificial.

I guess one question is, what is this abstracting, and is that
abstraction actually a shared need for multiple subsystems? I think
the abstraction is, "impending user activity; <component X> should
prepare itself". That general need is exactly the same for the cases
I'm aware of. And if there is any tuning needed (e.g., ignore input
device Y; or turn the whole thing off, because we're ignoring input
for now), that would also seem to be a shared need.

Anyway, back to my first paragraph: I'll plan on keeping this as-is
(as a DRM helper) unless I hear otherwise from input folks.

Brian

[1] https://lore.kernel.org/all/20180416174117.GA77055@dtor-ws/