Re: [PATCH v7 2/5] dt-bindings: leds: Add LED_COLOR_ID_MOONLIGHT definitions

Gene Chen
2020-11-24T07:34:07Z

Jacek Anaszewski <jacek.anaszewski@gmail.com> 於 2020年11月24日 週二 上午4:52寫道：
>
> On 11/23/20 4:00 AM, Gene Chen wrote:
> > Jacek Anaszewski <jacek.anaszewski@gmail.com> 於 2020年11月20日 週五 上午6:26寫道：
> >>
> >> On 11/19/20 10:57 PM, Pavel Machek wrote:
> >>> On Thu 2020-11-19 22:03:14, Jacek Anaszewski wrote:
> >>>> Hi Pavel, Gene,
> >>>>
> >>>> On 11/18/20 10:37 PM, Pavel Machek wrote:
> >>>>> Hi!
> >>>>>
> >>>>>> From: Gene Chen <gene_chen@richtek.com>
> >>>>>>
> >>>>>> Add LED_COLOR_ID_MOONLIGHT definitions
> >>>>>
> >>>>> Why is moonlight a color? Camera flashes are usually white, no?
> >>>>>
> >>>>> At least it needs a comment...
> >>>>
> >>>> That's my fault, In fact I should have asked about adding
> >>>> LED_FUNCTION_MOONLIGHT, it was evidently too late for me that evening...
> >>>
> >>> Aha, that makes more sense.
> >>>
> >>> But please let's call it "torch" if we do that, as that is already
> >>> used in kernel sources... and probably in the interface, too:
> >>
> >> I'd say that torch is something different that moonlight,
> >> but we would need more input from Gene to learn more about
> >> the nature of light emitted by ML LED on his device.
> >>
> >> Please note that torch is usually meant as the other mode of
> >> flash LED (sometimes it is called "movie mode"), which is already
> >> handled by brightness file of LED class flash device (i.e. its LED class
> >> subset), and which also maps to v4l2-flash TORCH mode.
> >>
> >
> > It's used to front camera fill light.
> > More brightness than screen backlight, and more soft light than flash.
> > I think LED_ID_COLOR_WHITE is okay.
>
> So why in v6 you assigned LED_COLOR_ID_AMBER to it?
>
> Regardless of that, now we're talking about LED function - you chose
> LED_FUNCTION_INDICATOR for it, but inferring from your above description
> - it certainly doesn't fit here.
>
> Also register names, containing part "ML" indicate that this LED's
> intended function is moonlinght, which your description somehow
> corroborates.
>
> Moonlight LEDs become ubiquitous nowadays so sooner or later we will
> need to add this function anyway [0].
>
> [0]
> https://landscapelightingoakville.com/what-is-moon-lighting-and-why-does-it-remain-so-popular/
>

We use term "Moonlight" as reference says
"When you are trying to imitate moonlight you need to use low voltage,
softer lighting. You don’t want something that’s too bright"
which is focus on brightness instead of color.

So we surpose Moonlight can be white or amber.

Should I add LED_FUNCTION_MOONLIGHT and set LED_COLOR_ID_WHITE?

> --
> Best regards,
> Jacek Anaszewski