Re: [PATCH RFC] leds: Add support for per-LED device triggers

From: OndÅej Jirman
Date: Sun Jul 12 2020 - 09:49:16 EST


Hello,

On Sun, Jul 12, 2020 at 09:25:54AM +0200, Pavel Machek wrote:
> On Sat 2020-07-11 23:01:11, OndÅej Jirman wrote:
> > Hello Pavel,
> >
> > On Sat, Jul 11, 2020 at 12:04:09PM +0200, Pavel Machek wrote:
> > > Hi!
> > >
> > > > Some LED controllers may come with an internal HW triggering mechanism
> > > > for the LED and an ability to switch between user control of the LED,
> > > > or the internal control. One such example is AXP20X PMIC, that allows
> > > > wither for user control of the LED, or for internal control based on
> > > > the state of the battery charger.
> > > >
> > > > Add support for registering per-LED device trigger.
> > > >
> > > > Names of private triggers need to be globally unique, but may clash
> > > > with other private triggers. This is enforced during trigger
> > > > registration. Developers can register private triggers just like
> > > > the normal triggers, by setting private_led to a classdev
> > > > of the LED the trigger is associated with.
> > >
> > > What about this? Should address Marek's concerns about resource use...
> >
> > What concerns? Marek's concerns seem to be about case where we register
> > a trigger for (each led * self-working configuration) which I admit
> > can be quite a lot of triggers if there are many functions. But that's
> > not my proposal.
> >
> > My proposal is to only register on trigger per LED at most. So on my
> > system that's 1 extra trigger and on Marek's system that'd be 48 new
> > triggers. Neither seems like a meaningful problem from resource
> > use perspective.
>
> So.. 48 triggers on Marek's systems means I'll not apply your patch.
>
> Please take a look at my version, it is as simple and avoids that
> problem.

I would, but I don't see your version linked or mentioned in this thread.

thank you and regards,
o.

> If it works for you, you can submit it properly and I'll likely accept
> it.
>
> Best regards,
> Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html