Set value of GPIO247 to 1

Question

I am currently trying to enable GPIO Port 247 it is located in GPIOCHIP7. The output of cat /sys/kernel/debug/gpio is

gpiochip7: GPIOs 224-255, parent: platform/48053000.gpio, gpio:
 gpio-226 (                    |reset               ) out hi
 gpio-227 (                    |sysfs               ) out hi
 gpio-228 (                    |pcie-reset          ) out hi
 gpio-229 (                    |sysfs               ) out lo
 gpio-230 (                    |id                  ) in  lo IRQ
 gpio-231 (                    |pcie-clk-oe         ) out hi
 gpio-247 (                    |enable              ) out lo

I need to set gpio-247 to hi.

My Linux kernel version is 4.9 and i am on a AM57x

I have tried these but to no avail

echo 247 > /sys/class/gpio/export returns "echo: write error: Device or resource busy".
echo 247 > /sys/class/gpio/unexport returns "echo: write error: Invalid argument".

i can echo everything except 247.