mmap a GPIO?

[jrestifo]

@vickyy

I tried using sysfs to modify the GPIO and read back using my code below, but it doesn’t work. Not sure what I am doing wrong

How about probing the signal? Does it reflect your sysfs controlling?

Yes, if I use sysfs I can verify the signal with my probe.

I think I may have GPIO_ADDR wrong in my code above - or maybe GPIO_SZ? I tried my best to match it to the TRM but again, I could not find the actual GPIO register definitions anywhere in the Xavier TRM… am I missing something?

edit
I can verify that the GPIO flips when I use sysfs, using my scope. However, nothing changes in the region I have mmap’d. Therefore, I must have the registers wrong… can someone please explain the mapping to me, and also point out where I can find the actual register definitions?