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If the new SAR value is less than > > the old one and the counter is greater than the new SAR value, the current > > period will not flip the level. This result in a pulse with a 100% duty > > cycle. > > > > Write the old SAR value before updating the new duty cycle to SAR. This > > avoids writing the new value into an empty FIFO. > > > > This only resolves the issue when the PWM period is longer than 2us > > (or <500KHz) because write register is not quick enough when PWM period is > > very short. > > > > Reviewed-by: Jun Li > > Signed-off-by: Clark Wang > > Signed-off-by: Frank Li > the same patch has been submitted from other people in the past and they > received many review comments [1], [2]. > > Can you please explain which version of the patch this is and does it > address any review comments? Thank, I am not realize someone already submitted before. I fixed some by common senses. Let me double check to make sure to fix all. Frank > > Best regards > > [1] - > https://lore.kernel.org/linux-pwm/20211220073130.1429723-1-xiaoning.wang@nxp.com/ > [2] - > https://lore.kernel.org/linux-pwm/20231229063013.1786-1-pratikmanvar09@gmail.com/