customs gpio driver

environment:jetpack 4.2
I need custom gpio driver, which c file need modify in source code?

Does this post help? It is well discussed how to use GPIOs in the Jetson TX2

Moreover, jchaves also details how to configure GPIOs in the DT in this post.

1.I know how to use GPIOs in the jetson TX2, i can control the pin creat a square wave of 10kHZ.
2. The reference URL jchaves provided is no longer valid.
questions: When I increased the frequency to 200kHZ, the square wave got distorted. bellow is the list of pins i have test. only gpio466 can creat a square wave of 200kHZ. Is there anything special about gpio466? How do I set the other pins to the same?
jetsonTX2GPIONumber gpio_group[GPIO_NUM_J21] =
{
gpio396, // J21 -Pin 7 0
gpio466, // J21 -Pin 11 1 0k
gpio397, // J21 -Pin 13 2
gpio255, // J21 -Pin 15 3
gpio429, // J21 -Pin 19 4
gpio428, // J21 -Pin 21 5
gpio427, // J21 -Pin 23 6
gpio398, // J21 - Pin 29 7
gpio298, // J21 -Pin 31 8
gpio389, // J21 -Pin 33 9
gpio395, // J21 -Pin 35 10
gpio388, // J21 -Pin 37 11

        gpio392,  // J21  -Pin 12 12
        gpio296_, // J21  -Pin 16 13
        gpio481,  // J21  -Pin 18 14
        gpio254,  // J21  -Pin 22 15
        gpio430,  // J21  -Pin 24 16
        gpio297,  // J21  -Pin 32 17
        gpio467,  // J21 - Pin 36 18
        gpio394,  // J21 - Pin 38 19
        gpio393,  // J21 - Pin 40 20
    };