Embedded Linux, Ioctl, SPI-Dev, I2C-Dev and FPGA

Article note: Cohesive accessible documentation about doing things across the PL-PS ("Programmable Logic-Processing System" Xilinx for FPGA-Hard Processor) boundary is hard to come by. This is a nice all-in-one example that at least covers all the shit involved in plumbing an IIC interface through Vivado and PetaLinux into user space on a Zynq.