Ubuntu 20.04 kernel 4.4

Does this OS support char dev GPIO? I do not see /dev/GPIOchip devices like I see on my Raspberry Pi. My Pi kernel version is 4.19. I am trying to use libgpiod. I can build my test application, but fails since the GPIO devices are not present. Sysfs interface is too slow for my application. Any suggestions?

I guess you are using rock pi 4? Which devices are you using?

Did you read the wiki?

Found the statement below in the above link:

β€œOn the older 4.4 kernels from Radxa,
chardev support is not available and libmraa
gracefully falls back to sysfs. β€œ