Linux also offers user space SPI via `spidev` (i.e. the "driver" consists of a registration call, and all communication is done via regular `read()`/`write()` c

Linux also offers user space SPI via `spidev` (i.e. the "driver" consists of a registration call, and all communication is done via regular `read()`/`write()` calls). For low performance applications, it works perfectly.