roboard GPIO ioperm permission linux

[jlmunix]

I want to use the GPIO ports of the Roboard without sudo command. So i decided to make a simple program to enable permissions to the ports.

Code: Select all

void main(void)
{
   int alm;
   iopl(3);
   if (ioperm(0x98, 3, 1))     //Set the permission to the port.
     {
        perror("ioperm");
        exit(1);
     }
}


If i run this program with sudo when i turn on the roboard, i will be able to use the ports from user speace without specifying the sudo command! It works (i tested)

But my question is, what´s up if i let all GPIO with write permission always? can i make a damage?

From here im enabled to R/W port with simple instruction:

Code: Select all

outportb(0x98, 0xff);


[roboard]

If only a single program uses GPIO, then it is no problem to let all GPIO with write permission always. If you want that multiple programs share GPIO simultaneously, you may need a Linux GPIO driver (unfortunately, such a driver does not exist currently).