Hello,
Using kernels from the rcn-ee Debian Jessie repository: 4.1.5-armv7-x2 or 4.2.0-rc6-armv7-x0, my beagleboard does not see its nand (mtd).
Those kernels have the onenand/omap2.ko driver but not the nand/omap2.ko.
Compiling a kernel without onenand (CONFIG_MTD_ONENAND not set) builds nand/omap2.ko, and the nand shows up on the system when loading the module.
Looks like having the same name for both modules causes the issue?