Re: [PATCH 2/3] dt-bindings: leds: add dt schema for worldsemi,ws2812b-spi

[Chuanhong Guo]

Hi!

On Wed, Nov 30, 2022 at 7:59 PM Krzysztof Kozlowski
<krzysztof.kozlowski@xxxxxxxxxx> wrote:
> >> [...]
> >> So this is brightness of each color...
> >
> > I don't think so.
> > See the kernel doc for multicolor LED:
> > https://docs.kernel.org/leds/leds-class-multicolor.html
> > This property sets the sysfs file multi_intensity while the
> > actual LED brightness is controlled with another sysfs
> > file called 'brightness'.
> > Setting multi_intensity alone doesn't change the LED
> > brightness at all.
>
> If you had brightness, that would be correct. But you do not have
> brightness, right?

The brightness can be set using sysfs, but I didn't implement a
default brightness in my driver.
My original intent for this property is to set a default color for legacy
led softwares which can only control the brightness and doesn't
support setting the color value yet.

> Therefore the final brightness is always:
>
> subled[i].brightness = 255 * subled[i].intensity / max_brightness (also
> 255);
>
> Or your bindings are incomplete...

I do agree that adding a default-brightness will make this more
useful. I'll add this feature in the next version.

-- 
Regards,
Chuanhong Guo