In the code I see the offset addresses for various registers defined. But, where is the base address registered ?
In the function, the base address is accessed through mcspi->base. How does mcspi->base contain the specific base address of McSPI ?
This should be defined in the dts file in arch/arm/boot/dts/omap4.dtsi file. I'm not sure if DT is enabled for your kernel. If enabled, it reads in the probe function.