Properly Propagate Protocol Problems (tcp::Error -> embeded_io::Error)

[avlec]

Currently there's no error translation for converting from embassy_net::tcp::Error to embedded_io::Error.
It is rather concerning to get a "Other" as an Error value instead of useful information that you have to get by breaking at the conversion spot in tcp.rs

embassy/embassy-net/src/tcp.rs

Line 515 in 97da345

impl embedded_io_async::Error for ConnectError {

I was seeing the embedded_io Other error when under the hood the actual error was ConnectionReset, which the function above converts to Other which loses all meaning.

[Dirbaio]

Agreed. This code predates adding all the variants to embedded_io_async::ErrorKind rust-embedded/embedded-hal#471, that's why it's this way. PR's welcome!

(also note you can inspect the ConnectError directly, you don't need to do .kind())

[avlec]

Yes, I was trying to get reqwless http lib to work, stumbled across this translation error when doing a debugger to a RP Pico W. So I was using a commit from this project from 2 weeks ago, and see that the 0.4 version of embedded_io at that point only had Other. So I could only see the error from the very outside, behind an HttpClient request returning an error.