Chris Clayton writes via Kernel.org Bugzilla: I've reverted* bede03a579b3b4a036003c4862cc1baa4ddc351f and built the 5.4.0-40 kernel**. The RTS5229 card reader in my NUC6CAYH now works with both SD and MMC cards. * The commit does not revert cleanly because of some later changes. The manual fix up is not too difficult, however. ** Actually, the build fails but after the modules have been built so the rtsx_pci.ko driver module is available in the build directory. I installed it by hand and then ran depmod manually. The build system is a maze of voodoo that I am still trying to untangle to get a full set of deb files produced. Nevertheless, my testing strongly suggests that commit bede03a579b3b4a036003c4862cc1baa4ddc351f is the culprit. I've also reverted the commit and built the resultant kernel on my (non-debian/ubuntu powered) laptop, which also has a card reader (RTL8411B PCI Express Card Reader) that needs this driver. That continues to work after he reversion. View: https://bugzilla.kernel.org/show_bug.cgi?id=204003#c14 You can reply to this message to join the discussion. -- Deet-doot-dot, I am a bot. Kernel.org Bugzilla (bugspray 0.1-dev)