The twai driver is tightly coupled to the embedded-hal/embedded-can packages

[jessebraham]

Ideally, all of our drivers should function without using any of the embedded-hal/embedded-can traits; these traits are only interfaces. Unfortunately, our twai driver is currently quite tightly coupled to these dependencies.

This needs to be fixed; I have started looking into this a bit, but unfortunately I think we will need to duplicate quite a few enums/structs from these packages :/

[jessebraham]

I don't really see a path forward here other than duplicating all the types from these packages and implementing the From trait as needed for everything. Seems this will be a bit painful.

[ptpaterson]

I will say that using the provided structs and enums from embedded_can is rather convenient. I'm working on a generic CAN library, and it'd be great if I can use ID instead of impl Into<ID> everywhere. But I definitely agree the traits shouldn't be required to use this HAL.

Can traits

#951 does create inherent impls for transmit and receive, which the trait impl then reuses.

Frame trait

It would indeed be nice to have some inherent methods to instantiate and use EspTwaiFrames without the Frame trait.

[jessebraham]

Let's use #1317 to track progress here moving forward.