linux-kernel - Re: [PATCH] dt-bindings: leds: Allow differently named multicolor leds

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z6ucAFNauWkhfYZr@probook>
Date: Tue, 11 Feb 2025 18:50:40 +0000
From: J. Neuschäfer <j.ne@...teo.net>
To: Lee Jones <lee@...nel.org>
Cc: j.ne@...teo.net, Pavel Machek <pavel@....cz>,
	Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>, Andrew Davis <afd@...com>,
	linux-leds@...r.kernel.org, devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] dt-bindings: leds: Allow differently named multicolor
 leds

On Tue, Feb 11, 2025 at 02:43:00PM +0000, Lee Jones wrote:
> On Sun, 09 Feb 2025, J. Neuschäfer via B4 Relay wrote:
> 
> > From: "J. Neuschäfer" <j.ne@...teo.net>
> > 
> > In some cases, a board may have multiple multi-leds, which can't be
> > distinguished by unit address. In such cases it should be possible to
> > name them differently, for example multi-led-a and multi-led-b.
> > This patch adds another node name pattern to leds-class-multicolor.yaml
> > to allow such names.
> 
> Which H/W needs this?  Is it upstream?  Where is the doc / usage?

I encountered this situation while upstreaming the LANCOM NWAPP2 board,
which has multiple LED-group-based multicolor LEDs:

  https://lore.kernel.org/lkml/20250102-mpc83xx-v1-16-86f78ba2a7af@posteo.net/

Since they are based on leds-group-multicolor, they don't have a unit
address, but there is more than one on the same level (as direct
sub-nodes of the DT root node).

I can add a comment about node names, if that's desired, e.g.:

  If multiple multi-color LEDs exist on the same level, they can be
  differentiated by unit-address (e.g. multi-led@...0) or name
  (e.g. multi-led-power).

Such as a comment doesn't exist currently either; the existing
"^multi-led(@[0-9a-f])?$" pattern is not documented in prose.

Best regards,
J. Neuschäfer

> 
> > Signed-off-by: J. Neuschäfer <j.ne@...teo.net>
> > ---
> >  Documentation/devicetree/bindings/leds/leds-class-multicolor.yaml | 4 +++-
[...]
> > +      - pattern: "^multi-led(@[0-9a-f])?$"
> > +      - pattern: "^multi-led-.*$"