My card reader doesn't seem to be able to recognise, let alone read, anything any more.
lspci -v lists the device:
06:00.0 SD Host controller: O2 Micro, Inc. SD/MMC Card Reader Controller (rev 01) (prog-if 01) Subsystem: Lenovo SD/MMC Card Reader Controller Flags: bus master, fast devsel, latency 0, IRQ 128, IOMMU group 15 Memory at e1001000 (32-bit, non-prefetchable) [size=4K] Memory at e1000000 (32-bit, non-prefetchable) [size=2K] Capabilities: [6c] Power Management version 3 Capabilities:  MSI: Enable+ Count=1/1 Maskable+ 64bit+ Capabilities:  Express Endpoint, MSI 00 Capabilities:  Virtual Channel Capabilities:  Advanced Error Reporting Capabilities:  Latency Tolerance Reporting Kernel driver in use: sdhci-pci Kernel modules: sdhci_pci
but when inserting an sd card,
dmesg shows zero activity because of it and
fdisk -l shows no additional device beyond the previously existing drives.
I've seen older posts about udev triggers, but I think the problem fails before that, as
fdisk doesn't even show a device has been found. Also
How do I debug this? I know the reader used to work a number of months ago. I am running debian/sid with a 5.7.0-2-amd64 kernel.