Is there any way to un-map the GPIO ports of Raspberry Pi 2 B. I am trying to build a driver to control the GPIO pins using the GPIO registers. The GPIO ports are mapped to (from cat /proc/iomem) 3f200000-3f2000b3 : /soc/gpio@7e200000. Now I tried to create a new mapping from 3f000000-3f00003f, but I am not able to read/write into this address. Do I need to un-map the default GPIO port address and then use my custom ports or something else. Please help?
Thank you
Re: GPIO port Un-Mapping
You are doing something wrong. Many processes can map the same memory. The contents of /proc/iomem are irrelevant to your problem.
Re: GPIO port Un-Mapping
Don't I need to disable the default GPIO port addresses before using my custom made address? I am trying to build a driver to control GPIO pins. I am referring this link http://www.codeproject.com/Articles/103 ... aspberryPi
and updated the PORT address to 3f000000. The module gets loaded without any problem but when I try to write some value into the port, I don't get any response. I have chose the address from 3f000000 to 3f00003f. Any leads will be appreciated.
Thank you.
and updated the PORT address to 3f000000. The module gets loaded without any problem but when I try to write some value into the port, I don't get any response. I have chose the address from 3f000000 to 3f00003f. Any leads will be appreciated.
Thank you.
Re: GPIO port Un-Mapping
Perhaps other things have changed in recent kernels. I did a kernel module some time ago, have a look for krydab.c in the search box and see if anything looks different.