Hi,
Am 20.11.23 um 21:52 schrieb Pavel Machek:
Hi!
So... a bit of rationale. The keyboard does not really fit into the
LED subsystem; LEDs are expected to be independent ("hdd led") and not
a matrix of them.
Makes sense.
We do see various strange displays these days -- they commonly have
rounded corners and holes in them. I'm not sure how that's currently
supported, but I believe it is reasonable to view keyboard as a
display with slightly weird placing of pixels.
Plus, I'd really like to play tetris on one of those :-).
So, would presenting them as auxdisplay be acceptable? Or are there
better options?
It sounds like a fair use case -- auxdisplay are typically simple
character-based or small graphical displays, e.g. 128x64, that may not
be a "main" / usual screen as typically understood, but the concept is
a bit fuzzy and we are a bit of a catch-all.
And "keyboard backlight display with a pixel/color per-key" does not
sound like a "main" screen, and having some cute effects displayed
there are the kind of thing that one could do in the usual small
graphical ones too. :)
But if somebody prefers to create new categories (or subcategories
within auxdisplay) to hold these, that could be nice too (in the
latter case, I would perhaps suggest reorganizing all of the existing
ones while at it).
One could also reasonably make the argument that controlling the
individual keyboard key backlights should be part of the input
subsystem. It's not a display per se. (Unless you actually have small
displays on the keycaps, and I think that's a thing too.)
While it would not be completely crazy to do that... I believe the
backlight is more of a display and less of a keyboard. Plus input
subystem is very far away from supporting this, and we had no input
from input people here.
I don't think LED subsystem is right place for this, and I believe
auxdisplay makes slightly more sense than input.
Unless someone steps up, I'd suggest Werner tries to implement this as
an auxdisplay. [And yes, this will not be simple task. RGB on LED is
different from RGB on display. But there are other LED displays, so
auxdisplay should handle this. Plus pixels are really funnily
shaped. But displays with missing pixels -- aka holes for camera --
are common in phones, and I believe we'll get variable pixel densities
-- less dense over camera -- too. So displays will have to deal with
these in the end.]
Another idea I want to throw in the mix:
Maybe the kernel is not the right place to implement this at all. RGB stuff is
not at all standardized and every vendor is doing completely different
interfaces, which does not fit the kernel userpsace apis desire to be uniformal
and fixed. e.g. Auxdisplay might fit static setting of RGB values, but it does
not fit the snake-effect mode, or the raindrops mode, or the
4-different-colors-in-the-edges-breathing-and-color-cycling mode.
So my current idea: Implement these keyboards as a single zone RGB kbd_backlight
in the leds interface to have something functional out of the box, but make it
runtime disable-able if something like
https://gitlab.com/CalcProgrammer1/OpenRGB wants to take over more fine granular
control from userspace via hidraw.
Kind regards,
Werner
Best regards,
Pavel
