I am trying to access the GPIOs on SAR2130P. These are the permissions and gpiochip*:
/ # ls -l /dev/gpio*
crw-rw---- 1 root gpio 254, 0 Jan 1 00:00 /dev/gpiochip0
crw-rw---- 1 root gpio 254, 1 Jan 1 00:00 /dev/gpiochip1
crw-rw---- 1 root gpio 254, 2 Jan 1 00:00 /dev/gpiochip2
As for gpio:
/sys/kernel/debug # cat gpio
gpiochip0: GPIOs 356-511, parent: platform/f000000.pinctrl, f000000.pinctrl:
gpio0 : in low func0 2mA pull down
Adding the base address, gpio0 becomes 357. I cannot export the gpio:
/sys/kernel/debug # echo 357 > export
/bin/sh: can't create export: Permission denied
ls -l does not list export.
Could you please let me know how I could set permissions. Thank you.