[root@imx6ull:~]# cat /sys/kernel/debug/gpio
cat: can’t open ‘/sys/kernel/debug/gpio’: No such file or directory
[root@imx6ull:~]# cd /sys/kernel/debug/
[root@imx6ull:/sys/kernel/debug]# ls
[root@imx6ull:/sys/kernel/debug]# ls -l
total 0
[root@imx6ull:/sys/kernel/debug]# ls -la
total 0
dr-xr-xr-x 2 root root 0 Dec 1 13:32 .
drwxr-xr-x 9 root root 0 Dec 1 13:32 …
[root@imx6ull:/sys/kernel/debug]#