GPIO access on UP4000

arnaudg

I'm trying to use the GPIOs for the UP4000 with Ubunto 20.04

I've installed the kernel 5.4.0 from PPA and the upboard-extras
I've created the GPIO, LED,... groups
But when I try to access the

cd /sys/class/gpio
root@up01:/sys/class/gpio# echo 432 > export
-bash: echo: write error: Invalid argument

If I use gpiodetect from pinctrl, I can well see the GPIO but I get errors doing accesses

arnaud@up01:/sys/class/gpio$ gpiodetect 
gpiochip0 [INT3452:00] (78 lines)
gpiochip1 [INT3452:01] (77 lines)
gpiochip2 [INT3452:02] (47 lines)
gpiochip3 [INT3452:03] (43 lines)
gpiochip4 [Raspberry Pi compatible UP GPIO] (28 lines)
gpiochip6 [ftdi-cbus] (4 lines)
arnaud@up01:/sys/class/gpio$ gpioget gpiochip4 0
gpioget: error reading GPIO values: Unknown error 517

The control of the LED is working well.
Is there some extra steps to do to get these working?

HarryChiu

Hi Sir

After installed the pinctrl.
Please reference this website and try again.
https://github.com/up-board/up-community/wiki/40Pin-Header

Best Regards,
Harry Chiu