Use watchdog timeout for LIN communication error handling

[JanPetterMG]

Implement a watchdog timeout to manage LIN communication errors by forcing a reboot after 8 seconds in a fault state. This change enhances the system's reliability during communication failures.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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Reviewing files that changed from the base of the PR and between 8666196 and 7c4d3b6.

📒 Files selected for processing (2)

• src/avr/DeskService.cpp
• src/avr/main.cpp

🚧 Files skipped from review as they are similar to previous changes (2)

• src/avr/main.cpp
• src/avr/DeskService.cpp

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📜 Recent review details

⏰ Context from checks skipped due to timeout. (6)

• GitHub Check: Minimal (esp32-c6-zero-b)
• GitHub Check: Minimal (attiny841)
• GitHub Check: Full (esp32-c6-zero-b)
• GitHub Check: Tidy (attiny841)
• GitHub Check: Tidy (esp32-c6-zero-b)
• GitHub Check: Format

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Summary by CodeRabbit

• Reliability
  • Added watchdog monitoring to improve recovery from stalled device communication.
  • Initialization now reports required packet failures, sounds an alert, and stops instead of continuing.
  • Communication failures are reported more consistently, with pending operations preserved for retry.
  • Successful communication now regularly refreshes device monitoring to support continued reliable operation.

Walkthrough

The AVR watchdog is now managed by DeskService. Initialization reports PID failures immediately. Successful encoder reads reset the watchdog. Encoder failures preserve pending. AVR entrypoints delegate directly to DeskService.

Changes

AVR watchdog and initialization flow

Layer / File(s)	Summary
Initialization watchdog and PID failure handling src/avr/DeskService.cpp	DeskService::begin() enables the 8-second watchdog. PID initialization failures now write I and a newline to Serial1, sound a tone, and return immediately. Successful initialization resets the watchdog.
Runtime watchdog and entrypoint delegation src/avr/DeskService.cpp, src/avr/main.cpp	Successful encoder reads reset the watchdog. Encoder failures return false without clearing pending. AVR setup() and loop() now call only desk.begin() and desk.handle().

Merge Risk: 🟡 Moderate · up to 7c4d3

The watchdog recovery behavior may not restart the device after a PID initialization failure if encoder communication continues, leaving the desk in a failed initialization state. This should be resolved before merging.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the main change: using a watchdog timeout to handle LIN communication errors.
Description check	✅ Passed	The description accurately describes the watchdog timeout, the 8-second reboot behavior, and the reliability goal of the changes.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 4 functions across 2 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch chore/wdt-fault-handling

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[coderabbitai]

Actionable comments posted: 1

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Team

Run ID: 2ff69679-bec8-4c3c-b347-7c93cf0b25ce

📥 Commits

Reviewing files that changed from the base of the PR and between 8dff308 and 8666196.

📒 Files selected for processing (2)

• src/avr/DeskService.cpp
• src/avr/main.cpp

Included review availability: Your plan provides up to 1 included review per hour; 0 remain after this review.

[coderabbitai]

Note

Docstrings generation - SUCCESS
Generated docstrings for this pull request at #31