[Discussion] Should sensor driver developers target embedded-hal-async only?

[asasine]

Hello, and first of all, great work on this project. It has been phenomenal to work in the embedded Rust world. With the introduction of embedded-hal-async in v1, how should sensor driver developers approach targeting the three possibly HALs (sync, async, and polling)?

In the drivers I've developed, I've exclusively targeted the async version, as I reason it can function as a superset of the blocking and polling version, it's the version I utilize, and it would be infeasible to target all three for me, but I want to get some insight from the HAL maintainers. Not knowing a ton about exactly how the async HAL is implemented, is this assumption safe? I suspect it isn't implemented as "blocking calls async but blocks synchronously until the future completes," but I could see a world where that could be true, thus unifying the HALs into a single version, simplifying the process for sensor driver developers to reach as many users as possible.