shared/tinyusb/mp_usbd_cdc: Fix short CDC TX timeouts.

[dpgeorge]

The mp_event_wait_ms() function may return earlier than the requested timeout, and if that happens repeatedly (eg due to lots of USB data and IRQs) then the loop waiting for CDC TX FIFO space to become available may exit much earlier than MICROPY_HW_USB_CDC_TX_TIMEOUT, even when there is no space.

Fix this by using mp_hal_ticks_ms() to compute a more accurate timeout.

The basics/int_big_mul.py test fails on RPI_PICO without this fix.

[dpgeorge]

@andrewleech @projectgus FYI

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.42%. Comparing base (0c28a5a) to head (880f7bc).

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #15339   +/-   ##
=======================================
  Coverage   98.42%   98.42%           
=======================================
  Files         161      161           
  Lines       21249    21249           
=======================================
  Hits        20915    20915           
  Misses        334      334           

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[andrewleech]

Ah that makes sense, thanks the fix looks good to me!

[github-actions]

Code size report:

   bare-arm:    +0 +0.000% 
minimal x86:    +0 +0.000% 
   unix x64:    +0 +0.000% standard
      stm32:    +0 +0.000% PYBV10
     mimxrt:   +16 +0.004% TEENSY40
        rp2:   +64 +0.007% RPI_PICO_W
       samd:   +28 +0.011% ADAFRUIT_ITSYBITSY_M4_EXPRESS

[robert-hh]

I do not know if that was the intention, but it does not change the odd behavior which I brought up in the discussion PR #15158 and to which @projectgus referred in issue #15298.

[andrewleech]

I do not know if that was the intention, but it does not change the odd behavior which I brought up in the discussion PR #15158 and to which @projectgus referred in issue #15298.

No I wouldn't expect this to affect / help with that one.
The fix for that one is still going to be somewhat complicated I feel, likely needing further changes in tinyusb itself to support.

[projectgus]

LGTM!