Newbie need help!

Hi all!
I am a newbie for android development, although I had some experiences on Linux. Now I try to develop a driver to communicate with other chip through McBSP3. I had searched for long time for some examples. But nothing was found. So I include plat/mcbsp.h in my source and call omap_mcbsp_config after I construct the struct for McBSP3. But system go to dead after calling. The error information say a NULL pointer was referenced. I think this pointer is element OMAP_MCBSP3 in omap_mcbsp array. This element isn’t exist, so system will die. I change it as OMAP_MCBSP1. The system work correctly. My question is: how to construct the element for McBSP3 in the global arrya omap_mcbsp? I search the key-word “OMAP_MCBSP3” between the script and source files of android kernel. No essential file was found.
I had already modify the MUX for MCBSP3 in u-boot. I think this has no relation of my question. It should be something control the construction of global array omap_mcbsp. But I don’t know what it is. I will be glad if someone could be kind to tell me. Thank you!



Any possibility at all that you could let people know which board you are talking about? There are four different boards