Does ELK allow us to write our own kernel-space device drivers to interface with peripherals? Are there any limitations/caveats or is this just like writing device drivers on standard embedded Linux?
Starting next week, we will release everything including of course Kernel and Yocto configuration for build it.
So you can write your own device drivers if you need to. If you need to interact with a HW device in a way that is not real-time critical, you have to write a normal Linux device driver.
If instead your driver needs to interact with the RTOS Cobalt Kernel in Xenomai, you need to write a Xenomai RTDM driver. We have two of these in the distro, one for the audio codec and another one for handling the sensors through SENSEI.