Chris Clayton writes via Kernel.org Bugzilla: I've done more investigating of this regression and I've narrowed it down to rtsx_pci_init_ocp() in drivers/misc/cardreader/rtsx_pcr.c. It is called by rtsx_pci_init_hw() (from the same source file. If a comment out that call, build and install the resultant kernel, the rts5229 reader and the card inserted in are detected and work fine. The machine is an Intel NUC Tall Arches Canyon NUC6CAYH Celeron J3455. I can't take this diagnosis any further because, as far as I can see, the only change the patch identified as the culprit (see comment 10 above) makes to rtsx_pci_init_ocp(), shouldn't be executed for the rts5229. So far, I've built and installed 5.7.12 and 5.4.54 the latter of which I am currently running on the machine. I think I tried an unpatched 5.7 series kernel earlier in my investagations and the card reader did not work. To be sure, I'll build an older 5.4 kernel that more closely matches the one currently included in Ubuntu 20.04, and check whether that works when rtsx_pc i_init_ocp() is not called. View: https://bugzilla.kernel.org/show_bug.cgi?id=204003#c15 You can reply to this message to join the discussion. -- Deet-doot-dot, I am a bot. Kernel.org Bugzilla (bugspray 0.1-dev)
