Arduino_H7_Video: handling errors at initialization time

[dmazzella]

handling errors at initialization time with added retry counter to avoid infinite wait on anx7625_wait_hpd_event

[CLAassistant]

All committers have signed the CLA.

[dmazzella]

the motivation for this pr is to be able to reboot the board in case the display (USBCVideo) does not turn on for some reason, unfortunately it often happens that after a reset (ota firmware update) of the board the display does not turn on again and a reset fixes this, the problem is that in my specific case it happens on “remote” machines and not being physically there to reset it this is a problem.

  // Initialize display
  int display_ec = Display.begin();
  if (display_ec != 0) {
    NVIC_SystemReset();
  }

for copleteness i use the USB-C to HDMI Adapter from Arduino store

[dmazzella]

@leonardocavagnis please take a look at it and let me know.

[leonardocavagnis]

Sounds good!
Just a small fix: the Display.begin() function returns 0 on success or a value >0 if it fails.

0: Success
1: Unknown error
2: Insufficient drawing memory buffer
(NEW) 3: Video controller initialization failure

[iabdalkader]

Changes in this PR break the USB-C display for me (also see #1075 which might be related). I think the main issue is anx7625_dp_get_edid fails for some displays, and then anx7625_dp_start never gets called. However, because the examples don't handle begin failing, they proceed to call other functions normally which somehow results in a hardfault. The same goes for waiting for HPD event. If you connect the board to a PC instead, and just wait, it hard-faults after a while.
I suggest we revert some of these changes, maybe keep the dp_start check, and fix the examples to handle begin failing. Note that calling begin multiple times, if it fails, does not work.