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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Mon, 16 Oct 2023 12:57:36 +0200
Message-ID: <CANiq72mfP+dOLFR352O0UNVF8m8yTi_VmOY1zzQdTBjPWCRowg@mail.gmail.com>
Subject: Re: Implement per-key keyboard backlight as auxdisplay?
To:     Pavel Machek <pavel@ucw.cz>
Cc:     Werner Sembach <wse@tuxedocomputers.com>, ojeda@kernel.org,
        Lee Jones <lee@kernel.org>, linux-kernel@vger.kernel.org,
        linux-leds@vger.kernel.org, linux-input@vger.kernel.org,
        "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>
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On Fri, Oct 13, 2023 at 9:56=E2=80=AFPM Pavel Machek <pavel@ucw.cz> wrote:
>
> 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).

Cheers,
Miguel