I know the DIO on the i.MX6 supports PWM.
The question is, does it support changing the polarity of the PWM?
I attempted to set the polarity and it would not let me ....
root@imx6:~# echo inversed > /sys/class/pwm/pwmchip0/pwm0/polarity
-sh: echo: write error: Function not implemented
polarity - Changes the polarity of the PWM signal (read/write). Writes to this property only work if the PWM chip supports changing the polarity. The polarity can only be changed if the PWM is not enabled. Value is the string "normal" or "inversed".