Bug ID: 1180336 Summary: [RPi4] No USB in rpi4b and rpi400 since v5.10 Classification: openSUSE Product: openSUSE Tumbleweed Version: Current Hardware: Other OS: Other Status: NEW Severity: Normal Priority: P5 - None Component: Kernel Assignee: email@example.com Reporter: firstname.lastname@example.org QA Contact: email@example.com Found By: --- Blocker: ---
RPi4's firmware doesn't support receiving two USB reset signals in a row, even though it's supposed to do so (funnily enough 3 resets in a row work fine). This leaves the xHC in a broken state for TW as both u-boot and Linux perform this operation.
I'm in contact with the RPi engineers and a firmware fix should show up eventually. That said we're in the middle of the holiday season, so we'll have to be patient. We could advise TW users to kexec into the same Linux image to trigger a third USB reset, which will fix the issue, but that seems overkill. Otherwise, I prepared a small kernel fix to bypass the reset signal if USB is already up. This fix will never make it upstream, as it's somewhat hacky. But I figure it'll be nice to port it to TW while we wait for the RPi foundation to publish a new firmware.