rp1lib - user space driver for the RP1 chip

People may have been wondering why I have been a little quiet on the forum of late and that pull requests to Remora have been slow to be merged. Well, I've been working away on getting SPI on the Raspberry Pi 5 working so that we can support the SPI version of Remora. I'm now happy to share where things are up to.

github.com/scottalford75/rp1lib

The BCM2835 library was the inspiration, a library that gave access to all the chip peripherals. Hopefully the rp1lib can become the start of something similar.

Rather than reinventing the wheel, the library utilises the gpiochip_rp1 library for GPIO and I've adapted the kernel Designware driver for user space.

Next step is to update the Remora component, which is not too far off as I've got the RPi version detection working already.

Getting closer. The remora-spi LinuxCNC component can now:

1. Detect the RPi 5 and initialise the RP1 SPI
2. Can come out e-stop! Comms are up when testing with an Octopus board, but getting some errors reported

Need to play with speed settings etc to see if that helps.

Getting very close now