Hi! > > Multicolor is a bit too abstract. Yes, we can have > > Green-Magenta-Ultraviolet LED, but so far all the LEDs we support are > > RGB, and not even RGB-White or RGB-Yellow variants emerged. > > > > Multicolor is not a good fit for RGB LED. It does not really know > > about LED color. In particular, there's no way to make LED "white". > > > > Userspace is interested in knowing "this LED can produce arbitrary > > color", which not all multicolor LEDs can. > > > > Proposal: let's add "rgb" to led_colors in > > drivers/leds/led-core.c, add corresponding device tree > > defines, and use that, instead of multicolor for RGB LEDs. > > > > We really need to do that now; "white" stuff can wait. > > > > RGB LEDs are quite common, and it would be good to be able to turn LED > > white and to turn it into any arbitrary color. It is essential that > > userspace is able to set arbitrary colors, and it might be good to > > have that ability from kernel, too... to allow full-color triggers. > > I am not against adding RGB if you want to somehow teach the subsystem > to mix arbitrary color (either by teaching it color curves or some > other way). But I think we shouldn't remove multicolor, and here's the > reason why: I'd not remove multicolor. It would be still there for non-RGB uses. (Sorry if I was unclear). But I may want to disable it for now, not to have ABI incompatibility in future. > Most of the time I have seen 2 LEDs per ethernet port, green and yellow, > but some ports have 2 Bi-Color LEDs, each consisting of green and > yellow. I think most of the time these are 2-terminal LEDs. > > So basically here we have, instead of a RGB LED, a GY LED (GY for > green/yellow). ... > So if we want to reasonably add support for this configuration of LEDs > and to offer the user to configure these DUAL modes via the trigger > API, I think these LEDs should be shown in the system as multicolor > LEDs. Yes, I guess multicolor may make sense there. Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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