Messages in this thread | | | From | Fabio Estevam <> | Date | Fri, 13 May 2022 07:53:23 -0300 | Subject | Re: [PATCH v3 3/4] ARM: dts: imx6qdl-colibri: backlight pwm: Simplify inverted backlight |
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Hi Max,
On Fri, May 13, 2022 at 7:27 AM Max Krummenacher <max.oss.09@gmail.com> wrote: > > From: Max Krummenacher <max.krummenacher@toradex.com> > > 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 <max.krummenacher@toradex.com>
Thanks for the rework:
Reviewed-by: Fabio Estevam <festevam@gmail.com>
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