EM7455: Missing "Event Report" notifying "Operating Mode" updates
In 1.20 we have introduced the logic to register for "Operating Mode Reporting" event reports during power transitions so that:
- We send DMS Set Event Report ("Operating Mode Reporting" = yes)
- We send DMS Set Operating Mode request ("Mode" = online)
- We receive DMS Set Operating Mode response ("Result" = success)
- We start a 10s timeout
- We receive the DMS Event Report indication ("Operating Mode" = online)
- We send DMS Set Event Report ("Operating Mode Reporting" = no)
- We complete the operation
It seems the EM7455 may miss sending the Event Report indication, and so the power up operation ends up timing out.
This EM7455 is FCC locked, so first we attempt a power up and we get Invalid Transition. Then, the Sierra-specific FCC unlock procedure is run via an external script. And then we attempt the power up again, which is where the Event Report indication is missed. In the attached log I updated the 10s wait timeout to 30s, and we still didn't get the indication, so it doesn't look like a timing issue, it's just not sent.
On power transitions happening after the FCC unlock has happened this issue is not seen, it only seems to happen during the transition to online after the FCC unlock has happened.
We could improve this logic by doing an explicit DMS Get Operating Mode operation if we get the timeout, and if the state is the one we requested, then we assume the operation was successful even if we didn't get the Event Report indication.EM7455_-FCC_locked-_missing_operating_mode_update_notification.txt