Lukasz Majewski <lu...@denx.de> wrote: > Hi Michal, > > > Output of the PWM block of i.MX SoCs is always zero volts when the > > block is disabled. This can caue issues when inverted PWM polarity is > > needed. With inverted polarity a duty cycle = 0% corresponds to solid > > high level on the output. If the PWM is dissabled its output > > instantly goes to solid zero which corresponds to duty cycle = 100%. > > > > To have a trully inverted PWM output configure the PWM pad as a GPIO > > with pull-up. Then switch the pad to PWM output whenever non-zero > > duty cycle is needed. > > Just to ask - Is your display equipped with power supply enable/disable > pin? > > As fair as I remember the trick to avoid flickering the display > was to disable the display (enable-gpio property) and set the PWM PIN > as GPIO to high in u-boot. > Unfortunately there are both types of displays. Some with an ENABLE pin, some without.
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