Basically you have some kind of hierarchy of crates according to the abstraction level, and those crates are owned by some loose organisation.
The trick is that the those crates are new and there is only very few MCU features exposed in them (and modern MCUs are so "big" that there is no real hope to get out of the situation quickly), so when you're doing a project, you either have to send a PR upstream and have it die there immediately or argue for days before it dies, or you have to fork the crate yourself. I couldn't find a way to add code in the namespace of a crate without actually re-compiling it.
It was extremely naive to split the crates horizontally and have only a limited group of people able to access the register they want to use, and not expose some kind of extension mechanism.
some examples: STM32F103 doesn't expose DMA, there is no provision for async SPI, no provision for changing the speed of any communication device (nor any bus for that matter). Which we could attribute to the thing being new, but drivers are already being written in such a way that thing are getting calcified like that, and the task of exposing all the functions of the MCU in rust is infinite, it has to be open to outsiders and that involve having a different slicing of API, and always making sure that from any configuration we can call release().
