Fedora 31 - Printer/Scanner

Well, now the print function has decided not to work as well.

Found this - may be the problem (posted 10 days ago):

https://bugs.launchpad.net/hplip/+bug/1853002

root@abox ~]# hp-scan
warning: hp-scan should not be run as root/superuser.

Run it as user!

This means the scanner is found (as expected)...

found USB scanner (vendor=0x03f0 [HP], product=0xc511 [ENVY 4500 series]) at libusb:001:012

...the problem may just be with HPLIP itself.

SOLVED -

I uninstalled hplip-3.19.10 (which is latest in fedora repo). Went to the HPLIP website:
https://developers.hp.com/hp-linux-i...nting/gethplip

Downloaded hplip-3.19.11.run, and ran it.

Second time I did this ... but, this time it worked. Both printer & scanner work as advertised.

I expect problems in the future since I always update with "dnf update". When we get to hplip-3.19.12, dnf won't know I need that. Guess I'll cross that bridge when I get to it.

Thanks for all your help and patience.

Thanks for the update.

I have an HP PhotoSmart C4180 All-In-One.
simplescan stopped working when I upgraded from Fedora 28 to 30.
So I have a similar problem.

Key observation: "sane-find-scanner" didn't find the scanner but "sudo sane-find-scanner" did. So this looks like a permissions problem.

found USB scanner (vendor=0x03f0 [HP], product=0x5711 [Photosmart C4100 series]) at libusb:003:006

libusb:003:006 means that it is using /dev/bus/usb/003/006. This would change if the AIO were moved to a different USB socket.

$ ls -l /dev/bus/usb/003/006 crw-rw-r--+ 1 root lp 189, 261 Dec 14 21:38 /dev/bus/usb/003/006

A temporary fix: "sudo chmod o+w /dev/bus/usb/003/006". After this, simplescan works. I'm pretty sure that it will again fail after a reboot since this device node will be recreated.

I'm not sure what the correct fix would be.

Perhaps adding the user to the "lp" group. But I don't know what being in the lp group is supposed to mean. Perhaps it is intended only for trusted daemons and the like.

Perhaps some program(s) should be setgid lp. Which program(s)?

Perhaps adding udev rules. I don't know how to do that appropriately.

$ ls -l /dev/bus/usb/003/006
crw-rw-r--+ 1 root lp 189, 261 Dec 14 21:38 /dev/bus/usb/003/006

Those are the permissions that I would expect. The user needs to be a member of the 'lp' group for rw access to the USB-connected scanner. To do this, open a terminal and type

su -c 'usermod -a -G lp <username>'

*Replace <username> with the real account name

It will take effect the next time the user logs out and back in again.