Re: [PATCH RFC 1/2] dt-bindings: leds-group-multicolor: Introduce default-intensity

Conor Dooley <[email protected]> Mon, 13 Jul 2026 17:34:49 +0100

Newsgroups	org.kernel.vger.linux-leds,org.kernel.vger.linux-devicetree
Message-ID	<20260713-undercoat-cranium-c018ab9ab642@spud>

On Mon, Jul 13, 2026 at 10:41:53AM +0200, Jonas Rebmann wrote:
> Hi Stefan,
> 
> Thanks, for CCing me here.
> 
> On 2026-07-13 10:23, Stefan Wahren wrote:
> > sorry, I missed this. Thanks for pointing to this patch. In general i'm
> > fine with this approach, but there is something which confuses me.
> > Looking at the description, there is the statement: [default-intensity]
> > "Defaults to 0".
> > This seems to be correct for the Linux implementation of
> > leds-pwm-multicolor, but is this really an expectation along all (multi
> > color) LEDs (at least for Linux)?
> 
> You are right, sadly the initialization default of some
> multicolor-LED drivers differs.

Hmm, I forget if you had a default in leds common.yaml, but you should
probably remove it in this case and move the default to the individual
led type if so, rather than wait for support in a driver that doesn't
zero initialise.

> > E.g. leds-group-multicolor init the intensity with the maximum. So all
> > users of leds-group-multicolor should specify default-intensity for each
> > sub LED to achieve a defined behavior without breaking existing behavior.
> 
> I agree, once support is added to one of the drivers that doesn't
> zero-initialize, the documentation needs updating (because as you say,
> backwards-compatibilty probably beats consistency here).
> 
> I'm also just noticing that my v3 for only the dt-bindings never arrived
> on the list (I think I was on a buggy b4 master), I'll re-send now.
> 
> Regards,
> Jonas
> 
> -- 
> Pengutronix e.K.                           | Jonas Rebmann               |
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