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Date:   Sun, 16 May 2021 20:31:35 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Doug Zobel <dougdev334@gmail.com>
Cc:     Rob Herring <robh@kernel.org>,
        Jacek Anaszewski <jacek.anaszewski@gmail.com>,
        linux-leds@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] dt: bindings: lp55xx: Add predefined LED pattern
Message-ID: <20210516183135.GA26985@duo.ucw.cz>
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Hi!

> > I don't know that this belongs in DT though. Won't a user want to create
> > their own patterns? That means there should be a sysfs interface (which
> > we either already have or has been attempted IIRC).
>=20
> Yes, there is a sysfs interface for running patterns via the firmware
> loading interface.  The firmware loading interface doesn't seem well
> suited for constantly changing the pattern that the LED driver runs.
> I found it to be slow and unreliable when quickly changing the LED
> pattern.  The existing predef pattern functionality works much better.
> Unfortunately the only way to define the patterns for it is via the
> platform data structure.  Adding the predef patterns to the device
> tree seemed like a good way to make use of the existing functionality
> in the driver.

Take a look at the pattern trigger. That's the way to change patterns
at runtime, no need for firmware loading.

I may even have compiler from that interface to the bytecode lp55xx
uses. Some assembly will be required. Doing so with the RGB LED will
be even more fun.=20

We'll want to deprecate the firmware loading interface at some point.

Forget the device tree, that will not help you.

Best regards,
								Pavel
--=20
http://www.livejournal.com/~pavelmachek

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