Arch Linux

Description:

My scanner stopped to work. After investigation I found out that my user added to scanner group doesn't have permission to scanner device file in /dev.

After running systemctl restart systemd-udev-trigger.service the device file gets proper ACLs and scanner is detected by xsane or scanimage -L.

The investigation showed that this service is run during boot but before the scanner is even detected:

$ lsusb |grep -i mustek
Bus 001 Device 007: ID 055f:021e Mustek Systems, Inc. BearPaw 1200 TA/CS
$ journalctl -b |grep 021e
Oct 16 18:42:30 linux kernel: usb 1-10.1: New USB device found, idVendor=055f, idProduct=021e, bcdDevice= 1.00
$ journalctl -b |grep Coldplug
Oct 16 18:42:29 linux systemd[1]: Starting Coldplug All udev Devices...
Oct 16 18:42:29 linux systemd[1]: Finished Coldplug All udev Devices.

I downgraded sane, systemd, systemd-libs, linux kernel few months back but it seems not related. I upgraded my PC (new motherboard) recently and I think this might be related. Sadly don't have old mobo anymore.

More info about scanner permissions: https://bbs.archlinux.org/viewtopic.php?id=259884

My hardware:
Motherboard: Gibabyte B550M AORUS PRO (rev. 1.0)
Scanner: Mustek BearPaw 1200 TA

systemd: 246.6-1
linux: 5.8.14.arch1-1
sane: 1.0.31-1
libusb: 1.0.23-2

How to reproduce:
??...