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SubjectRe: [PATCH v3 3/4] ARM: dts: imx6qdl-colibri: backlight pwm: Simplify inverted backlight
Hi Max,

On Fri, May 13, 2022 at 7:27 AM Max Krummenacher <> wrote:
> From: Max Krummenacher <>
> Set #pwm-cells to the default 3 to gain access to the parameter
> which allows inverting the PWM signal. This is useful to specify
> a backlight which has its highest brightness at 0.
> With the change to use the PWM with inverted polarity the PWM signal
> is inverted to how it was before this patch.
> This changes the meaning of the values in the brightness-levels
> property. I.e. the duty-cycle changes from x/255 to (255-x)/255.
> Keeping the brightness-levels will then have a big brightness
> jump from 0 to 127 duty cycle, the other 6 steps will then be
> barely noticeable.
> Change the brightness-levels to provide the same brightness-levels
> as before.
> Signed-off-by: Max Krummenacher <>

Thanks for the rework:

Reviewed-by: Fabio Estevam <>

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