Kernel drivers on the BeagleBone
The proper means to support hardware on the BeagleBone is with a Linux kernel driver. This includes both stock hardware on the BeagleBone and any new added hardware. Using a kernel driver avoids the preceding drawbacks and allows maximum performance benefits. The resources on the SoC can be used with minimal difficulty. Access to things such as DMA and interrupts are very difficult in user space but are relatively straightforward in the kernel.
Writing a device driver is beyond the scope of this introductory book. However, advanced beginners should be aware of how to build the kernel. The Linux kernel is well written and cross compilation is easily done. Building the kernel can be done in a series of steps. You will need a cross compiler. The sample command lines assume the cross compiler prefix is arm-none-eabi-
. If you have a different compiler setup, replace that prefix with yours. All the following commands will have ARCH=arm
to tell the kernel build system...