Debugging USB Type-C Power Delivery: Beauty and the Beast
summary
The RADXA ROCK 5B refuses some Type‑C chargers: it boots fine on upstream Linux v6.13.1 but boot‑loops on Radxa’s downstream v6.1 because PD negotiation often exceeds the 5 second negotiation window. Both sides use an onsemi FUSB302B controller; the test harness is a prototype Testing in a Box v2 power source. Debugging uses logic analyzers, PicoScope, PD triggers (CY12/Twinky), and USB testers; fixes in U-Boot TCPM and the fusb302 kernel driver resolve the loop and let the board negotiate power successfully.
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chapters (9)
- 0:00Welcome
- 1:25USB Type-C Power Delivery overview
- 13:26Hardware overview
- 26:48Debugging tools
- 33:36Analyzing PD traces
- 35:23Testing in a Box debugging
- 37:33U-Boot TCPM debugging
- 38:58Linux kernel PD support
- 39:40Live PD debugging demo
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