Re: [PATCH 4/7] ARM: dts: Enable N950 keyboard sleep leds by default

From: Pavel Machek
Date: Tue Mar 29 2016 - 13:54:50 EST


On Tue 2016-03-29 16:52:09, Sebastian Reichel wrote:
> Hi,
>
> On Tue, Mar 29, 2016 at 12:51:28PM +0200, Pavel Machek wrote:
> > For 1-3 in the series, Acked-by: Pavel Machek <pavel@xxxxxx>
> >
> > > Like the Nokia N900, the N950 has leds to show
> > > the state of sys_clkreq and sys_off_mode pins.
> > >
> > > A detailed description for the LEDs and
> > > OMAP's sleep states can be found in Tony's
> > > commit for the Nokia N900:
> > >
> > > c1be2032f66df9e1238bd5bc4ca666de88a62abc
> >
> > I must say I've seen it on N900, and yes, it is useful, but no, I
> > don't think this is right.
> >
> > This is not a LED. This is a interface that changes meaning of two
> > other LEDs. I guess it should go to debugfs somewhere.
>
> I don't think we should diverge N900 and N950 userspace
> APIs in this regard.

That's a good argument.

But maybe we should move both to debugfs somewhere before we get too
much userspace that relies on it...

> Actually the correct way would be a custom trigger
> for the leds IMHO. I don't know if the led framework
> supports per led custom triggers, though.

Well, not even custom trigger would make this easy: AFAIK you need to
enable this on two LEDs or not at all, so you'd have one trigger _that
would need to be shared over two LEDs_.

Best regards,
Pavel
--
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