ports/raspberrypi: pull Pico-PIO-USB deterministic SYNC realignment (Fruit Jam USB host wedge)#11135
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ports/raspberrypi: pull Pico-PIO-USB deterministic SYNC realignment (Fruit Jam USB host wedge)#11135mikeysklar wants to merge 1 commit into
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The PIO USB receiver can lock onto an incoming packet a few bits early, so every byte arrives shifted and the aligned CRC check fails on wire data that is perfectly valid. The device retransmits forever and the endpoint is stuck until reboot. On the Fruit Jam this presents as hub hot plug delivery dying permanently, gated by unrelated build flags (vectorio compiled in but never imported), because the firmware memory layout steers the timing that decides the framing. Pulls sekigon-gonnoc/Pico-PIO-USB#211, which keys the realignment on the SYNC byte (0x80) to derive the exact shift and recover the packet. Fixes the 3-year-old sekigon-gonnoc/Pico-PIO-USB#97. DRAFT: submodule temporarily points at the mikeysklar fork so CI can fetch the commit. Repoint to the upstream sekigon-gonnoc SHA and restore the .gitmodules URL once adafruit#211 merges.
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DRAFT. Do not merge as is: the submodule temporarily points at my Pico-PIO-USB fork so CI can fetch the commit before it exists upstream.
Pulls the Pico-PIO-USB deterministic SYNC realignment (sekigon-gonnoc/Pico-PIO-USB#211) into the raspberrypi port.
The PIO USB receiver can lock onto an incoming packet a few bits early, so every byte arrives shifted and the aligned CRC check fails on wire data that is perfectly valid. The device retransmits forever, and the endpoint is stuck until reboot. On the Fruit Jam this presents as hub hot plug delivery dying permanently, gated by unrelated build flags (vectorio compiled in but never imported), because the firmware memory layout steers the timing that decides the framing. Full investigation with captures: hathach/tinyusb#3776.
Fixes #10563. Same root cause as the 3-year-old sekigon-gonnoc/Pico-PIO-USB#97.
Because a correct packet always begins with SYNC (0x80), the shift is not a guess: the fix drops leading bits until SYNC reappears, confirms with the PID check nibble and a recomputed CRC, then delivers. One observed offset, the captured bytes shifted vs the expected packet:
Validated on the Fruit Jam layout that previously wedged the port on the first hub hot plug and never recovered: 34 consecutive hot plug events all delivered across an automated cycling harvest.