linux-kernel - AW: [PATCH v1] leds: lp50xx: add setting of default intensity from DT

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: <DB8P190MB0634880713B530F51F95CEE0D9B49@DB8P190MB0634.EURP190.PROD.OUTLOOK.COM>
Date:   Wed, 3 Feb 2021 17:10:30 +0000
From:   Sven Schuchmann <schuchmann@...leissheimer.de>
To:     Pavel Machek <pavel@....cz>
CC:     Dan Murphy <dmurphy@...com>, Rob Herring <robh+dt@...nel.org>,
        "linux-leds@...r.kernel.org" <linux-leds@...r.kernel.org>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: AW: [PATCH v1] leds: lp50xx: add setting of default intensity from DT

Hello Pavel,

> 
> Yes, sounds reasonable. Could we get default intensity of 100% on all
> channels if nothing else is specified?
> 
> Or maybe simply "if intensity is not specified, start with 100%, and
> use explicit =0 if other color is expected".
> 
Mh, if someone is already using the led driver and updates to a newer kernel 
we would then turn on all leds per default to the maximum intensity during boot 
until they are set the way they should be from userspace. I don't know if this
is what we want? If yes, sure, we could set them to maximum per default.

Also if we want to use Percentage Values (%) for setting the intensity
I think this should also be done for the userspace interfaces and not only from DT. 
So at this time setting the RGB-LED to white is done like this:
echo "255 255 255" > /sys/class/leds/rgb\:led/multi_intensity
would then get 
echo "100 100 100" > /sys/class/leds/rgb\:led/multi_intensity
Again over here: If we would change it would break earlier Applications
from userspace. Just my thoughts. What do you think?

Best Regards,

   Sven