GPIO on MPC8308ERD board

ismaelfaye · ‎09-25-2012

Hi all,

I am using MPC8308erdb board and right now I want to have futher information about the GPIO in the CPU. What I want to do, is to access (write and read) the GPIO registers, to enable interruption... But I am confused when I look at the source code of the BSP and I guess you will help me.

My question is How is the GPIO handled by the drivers in the kernel? where is the GPIO driver defined? in which file? I ask these questions because I am a bit confuse. I see in the source code that we have ../drivers/gpio/gpiolib.c and we also have ../arch/powerpc/sysdev/mpc8xxx.c... And the question is which one must be used to handle the GPIO on MPC8308erdb board.

And can you explain me how to manage the GPIO? What I have to do, to change in the source code? Which driver do I have to use?

Thank you in advance.

Best regards,

Ismael FAYE

lunminliang · ‎05-15-2013

Just post comment for more users to refer.

There is no special driver for accessing to GPIO in this BSP. Use mmap command. It is a POSIX-compliant Linux/Unix system call that maps files or devices into memory. It is a method of memory-mapped file I/O. For example, look at the following links (http://en.wikipedia.org/wiki/Mmap) and (http://beej.us/guide/bgipc/output/html/multipage/mmap.html).