From: Chase Venters <chase.venters@clientec.com>
To: Richard Purdie <rpurdie@rpsys.net>
Subject: Re: best way to handle LEDs
Date: Wed, 2 Nov 2005 02:01:45 -0600
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On Tuesday 01 November 2005 06:38 pm, Richard Purdie wrote:
> led triggers would be connected to leds via sysfs. Each trigger would
> probably have a number you could echo into an led's trigger attribute.
> Sensible default mappings could be had by assigning a default trigger to
> a device by name in the platform code that declares the led.
>
> A trigger of "0" would mean the led becomes under userspace control via
> sysfs for whatever userspace wishes to do with it.

Any reason to represent the triggers as numbers in sysfs? I'm a fan of how the 
IO scheduler is chosen on a block device. The file looks like:

noop [anticipatory] deadline cfq

You get a list of all available triggers, which one is active (and it's easy 
enough for user space code to parse). Obviously, to select a trigger, you 
just write its name to the file. Instead of 0, you say user, etc...

Cheers,
Chase Venters
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