The PWM on the RK3568 with RK628 board has a hardware inverting
circuit to improve drive strength.
Therefore, software needs to change the PWM polarity to get
the desired PWM output.
Change-Id: I3a87d6aa16c4e09780a566117e4864d8d235038e
Signed-off-by: Guochun Huang <hero.huang@rock-chips.com>
Signed-off-by: Algea Cao <algea.cao@rock-chips.com>
Signed-off-by: Shunhua Lan <lsh@rock-chips.com>
Signed-off-by: Chaoyi Chen <chaoyi.chen@rock-chips.com>