I have a problem with imx6q pwm.
echo 0 >/sys/class/pwm/pwmchip1/export
echo 100 >/sys/class/pwm/pwmchip1/pwm0/period
echo 50 >/sys/class/pwm/pwmchip1/pwm0/duty_cycle
echo 1 >/sys/class/pwm/pwmchip1/pwm0/enable
I set pwm period is 100ns, duty_cycle 50ns, means that the pwm frequency is 10MHz, duty is 50%, but the oscilloscope shows the pwm frequency is 11MHz, and when the period is 92-100, the frequency is always 11MHz, when the period is 90, the frequency is 13.2MHz.
why is that? I check the pwm clock ,is 66MHz.