Ease of development is underestimation. I’ve built a few user space Linux drivers for SPI and USB devices. Was easy, I have consumed stable APIs exposed by usb

Ease of development is underestimation. I’ve built a few user space Linux drivers for SPI and USB devices. Was easy, I have consumed stable APIs exposed by usbdevfs, libudev, and a few others. No need to recompile OS kernel. Because Linux kernel API is stable, not only OS kernel upgrades don’t break my stuff, they don’t even require me to recompile my code. Creating a kernel mode Linux driver is much harder in comparison. Merging a driver into the mainline Linux is borderline impossible. Even Google with all their corporate resources and platinum membership of Linux foundation was unable to do so, instead they are supporting many thousands lines of patches: https://source.android.com/devices/architecture/kernel/android-common https://source.android.com/devices/architecture/kernel/andro... It’s safe to assume you won’t be able to push your custom driver either. You’ll have to do it the same way as everyone else — patch locally. This is not trivial either, but this time the challenge is technical, not political, as Linux kernel doesn’t have stable API nor ABI: https://github.com/torvalds/linux/blob/master/Documentation/process/stable-api-nonsense.rst https://github.com/torvalds/linux/blob/master/Documentation/...