- Why I did it
Fix issue: psu might use wrong voltage sysfs which causes invalid voltage value. The flow is like:
1. User power off a PSU
2. All sysfs files related to this PSU are removed
3. User did a reboot/config reload
4. PSU will use wrong sysfs as voltage node
- How I did it
Always try find an existing sysfs.
- How to verify it
Manual test
- Why I did it
* To support systems with dynamic port configuration
* Apply lazy initialization to faster the speed of loading platform API
- How I did it
* Add module.py to implement dynamic port configuration (aka line card model)
* Adjust chassis.py, platform.py, thermal.py, sfp.py to support dynamic port configuration
* Optimize existing code
- How to verify it
Platform regression on MSN4700, MSN3800 and MSN2700, 100% pass
Unit test covers all new changes.
