cant use any GPIO pin from python (Adafruit)

Hello,

i have the Beaglebone Black. few weeks back was OK and I used to learn and do few projects. then I updated to latest Debian image (ver 9) and latest kernel.

However, I found out that none of my previous Python projects (via Adafruit_BBIO) will work. All complain about the GPIO (permission mostly even though I am running as usual as SUDO. note: they are all existing projects and all worked fine before).

Further tests revealed that only Adafruit libraries are not working, If I rewrite the test in bonescript, all work fine.

I went to /sys/class/GPIO, it seems all my GPIO pins are exported and cannot be exported or unexported (write error, invalid argument). however i can cd to any GPIO and set direction, value and the tests work.

Any idea what is going one here?

I have no other processes running and I have rebooted several times. I have updated to latest Adafruit_BBIO but no change. Rebooted several times, no change.

Thanks in advance.

Please paste the exact error messages that you received.

Thanks,
Drew