Re: [PATCH v7 1/2] dt-bindings: backlight: mp3309c: remove two required properties

From: Daniel Thompson
Date: Thu Nov 16 2023 - 06:59:43 EST


On Thu, Nov 16, 2023 at 11:53:18AM +0100, Flavio Suligoi wrote:
> The two properties:
>
> - max-brightness
> - default brightness
>
> are not really required, so they can be removed from the "required"
> section.
> The "max-brightness" is no longer used in the current version
> of the driver (it was used only in the first version).
> The "default-brightness", if omitted in the DT, is managed by the
> device driver, using a default value. This value depends on the dimming
> mode used:
>
> - for the "analog mode", via I2C commands, this value is fixed by
> hardware (=31)
> - while in case of pwm mode the default used is the last value of the
> brightness-levels array.
>
> Also the brightness-levels array is not required:
>
> - in "analog mode", via I2C commands, the brightness-level array is
> fixed by hardware (0..31).;
> - in pwm dimming mode, the driver uses a default array of 0..255 and
> the "default-brightness" is the last one, which is "255"
>
> NOTE: there are no compatibility problems with the previous version,
> since the device driver has not yet been included in any kernel.
> Only this dt-binding yaml file is already included in the current
> v6.7.0-rc1 kernel version.
> No developer may have used it.
>
> Other changes:
>
> - improve the backlight working mode description, in the "description"
> section
> - update the example, removing the "max-brightness" and introducing the
> "brightess-levels" property
>
> Signed-off-by: Flavio Suligoi <f.suligoi@xxxxxxx>
> Acked-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>

Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>


Daniel.