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Day43 Log - Input Subsystem

Progress

  • Implemented GPIO input driver
  • Integrated debounce with delayed_work
  • Designed click state machine
  • Implemented short / long / double click detection
  • Verified input events via evtest

Observations

  • input_report_key requires both press and release
  • input_sync is required to flush event
  • evtest shows raw event but not behavior
  • terminal behavior depends on userspace interpretation

Issues

  • dtc include path problem (fixed via include path / cpp)
  • sed parsing error in test script (replaced with awk)
  • evtest not installed initially

Result

✔ Input event correctly generated
✔ Userspace can receive events
✔ System behavior verified

Key Takeaways

- Input subsystem handles event distribution
- Kernel provides mechanism
- Userspace defines behavior
- State machine needed for complex input