Angus Gratton

Have updated this branch a bit, and also submitted a draft set of micropython-lib changes at https://github.com/micropython/micropython-lib/pull/558

@turmoni Great plan! I think you are correct, there are 3 TinyUSB usbd_priv.h interface function calls: `usbd_edpt_stall`, `usbd_edpt_clear_stall`, and `usbd_edpt_stalled` that are not exposed via the Python API yet, but...

Thanks @turmoni. At a glance this looks quite good to me! I haven't had time to run it, might be a while before I have that time. ~~I don't think...

OK, what I confidently wrote just before is totally wrong - there are currently a bunch of places where an event hook may call back into `tud_task_ext()`, which is quite...

@turmoni Thanks for working through this in so much detail. I'm going to look into some of these items soon and get back to you.

This PR has been rebased on master, but without any other significant code changes yet.

Rebased again to remove the commit that updates the micropython-lib submodule. I'll try to avoid rebasing again during development to stop breaking history for others. If checking this out then...

Rebased, made a bunch of fixes around transfer cleanup and how exceptions in USB device callbacks are handled. (These are an inevitability on ports like rp2 which call into TinyUSB...

Rebased and pushed some more code changes, including some changes to the CPython interface. Will explain more on the linked micropython-lib PR.

@PythonLinks Your project sounds exciting! I'm not sure exactly how this PR fits in, but if you have a goal that requires a custom USB interface that then goes via...