Re: [PATCH] leds-pwm: the startup brightness can be specified

[Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>]

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Hi!

> > +        led.default_brightness = LED_OFF;
> > +        of_property_read_u32(child, "brightness",
> > +                     &led.default_brightness);
> 
> At first you would have to submit a patch for
> Documentation/devicetree/bindings/leds/common.txt that would add
> brightness property. The question is whether it is really needed?
> You can set brightness from userspace via sysfs API.
> 
> By the way, I have a question to DT maintainers: is DT a proper
> place for defining this type of configuration that can be set via
> userspace scripts? Shouldn't DT describe only hardware properties and
> constraints resulting from board configuration?

Well, if the hardware has label "half - power, full - transmitting" on
a LED, we might want kernel to turn it to half power on bootup.

If you have a "disk activity LED" on a PC, it is driven by
hardware. On arm notebook, it would be nice if "disk activity LED"
worked, too. Preferably even when running fsck in init=/bin/bash
mode. We already provide that, AFAICT, so having ability to set
constant brightness sounds sane to me.

									Pavel

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