BPI-R3 FAN Stops after openwrt loading - 23.05.03

Hi, New to BPI-R3 world.

23.05.03 Snapshot or local build, sd card boot, after power-on during uboot etc, fan start working as expected. But after kernel completes booting, just before openwrt console becomes ready, fan stops working. generic pwm driver is in place.

As stated at BPI-R3 Getting Started for the PWN FAN commands (Getting Started BPI-R3 | BananaPi Docs), do not work.

root@OpenWrt:/# echo 0 > /sys/class/pwm/pwmchip0/export
cash: write error: Resource busy
root@OpenWrt:/# echo 10000 > /sys/class/pwm/pwmchip0/pwm0/period
/bin/ash: can't create /sys/class/pwm/pwmchip0/pwm0/period: nonexistent directory
root@OpenWrt:/# echo 5000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle
/bin/ash: can't create /sys/class/pwm/pwmchip0/pwm0/duty_cycle: nonexistent directory
root@OpenWrt:/# echo normal > /sys/class/pwm/pwmchip0/pwm0/polarity
/bin/ash: can't create /sys/class/pwm/pwmchip0/pwm0/polarity: nonexistent directory
root@OpenWrt:/# echo 1 > /sys/class/pwm/pwmchip0/pwm0/enable
/bin/ash: can't create /sys/class/pwm/pwmchip0/pwm0/enable: nonexistent directory

With Sinovip’s openwrt 21.03, fan works just fine.

am I missing something?

Do yow know this?

I didnt know, thanks!