Samsung scanner CLX-3185

Help
1

Hi,

has anyone been able to use the scanner function of the CLX-3185 multifunction printer with nixos (or with any other Samsung CLX series scanner/printer )?

I’ve been following Scanners - NixOS Wiki and tried several options, but still no scanner available.

Thx

2

Hi,

how can I remove a kernel module from the blacklist in configuration.nix ?

I want to try if I can access to my samsung scanner by removing usblp from the blacklisted modules

Thx

3 
  boot.blacklistedKernelModules = lib.mkForce [ ];

Will make it an empty list despite the other module’s config.

I’d check whether other modules put some values into the list beforehand though.

4

Thx for the answer.

But even with the usblp module loaded, I still can’t use my scanner. I’ve a working configuration on Fedora with that scanner, still not figured out what’s different between my nixos config and fedora. But I don’t give up :smiley:

5

Hi,

I finally found a hack to use the scanner.

I added the following line
tcp 192.168.1.240
at the end of the file
/nix/store/**hash**-sane-config/etc/sane.d/xerox_mfp.conf
192.168.1.240 is of course the ip of my multifunction printer

the result of scanimage -L is now
device xerox_mfp:tcp 192.168.1.240 is a Samsung Samsung CLX-3180 Series multi-function peripheral

I’m now able to use my scanner, but this isn’t a long term solution.

Any ideas how to convert this hack into a nixos configuration ?

Thx

6

Which module generates that file and puts it in your env?

Have you tried this option?

7

Hi,
I was able to look at my issue again. The files are installed by sane-backends

I tried to add the line tcp 192.168.1.240 to the xerox_mfp.conf file with the following overlay

(final: prev: {
  sane-backends = prev.sane-backends.overrideAttrs (oldAttrs: {
    postInstall = (oldAttrs.postInstall or "") + ''
        FILE=$SANE_CONFIG_DIR/xerox_mfp.conf
        IP=192.168.1.240

        if [[ -f "$FILE" ]]; then
            if ! grep -Fxq "tcp $IP" $FILE; then
                echo "tcp $IP" >> $FILE
            fi
        fi
    '';
  });
})

But sane-backends is linked to multiple packages (libreoffice, gnome…) so everything has to be recompiled.

Is there another solution to add this line without having to recompile everything ?

Thx

8

You’d want a more targeted approach; only override sane-backends in the package which need it rather than globally.

Which package would that be and where is it actually used (is it a daemon or a library? Who uses the library?)

9

sane-backends is installed if I enable the option hardware.sane.enable

option declared in this module https://github.com/NixOS/nixpkgs/blob/c93e5ab157b45adbb6165bd85a9d8f67e49ff31d/nixos/modules/services/hardware/sane.nix#L38

10

https://github.com/NixOS/nixpkgs/blob/c93e5ab157b45adbb6165bd85a9d8f67e49ff31d/nixos/modules/services/hardware/sane.nix#L7-L10 declares the package used for saned.

As a proof of concept, rebuild your system from a local Nixpkgs checkout and apply your override to that package.

11

Hi,
I finally found some time to tinker with nixos, and I came up with a configuration that allows me to use my scanner.

  hardware.sane = {
    enable = true;
    extraBackends = [
      (pkgs.runCommand "my-xerox_mfp.conf" { } ''
        mkdir -p "$out/etc/sane.d"
        echo "tcp 192.168.1.240" >> "$out/etc/sane.d/xerox_mfp.conf"
      '')
    ];
  };

but I have a warning when I build my configuration

warning: conflict for /nix/store/agk41d73x62brm88lcc0p699rvnxac9i-sane-config/etc/sane.d/xerox_mfp.conf. Overriding /nix/store/s6s1cpsqpspg43dv1wrangkabwm1hb6r-sane-backends-1.1.1/etc/sane.d/xerox_mfp.conf with /nix/store/fya6v9ryca6jivdzy8s0086pbhsbjd0g-my-xerox_mfp.conf/etc/sane.d/xerox_mfp.conf.

Question : is there a way to merge these two versions of xerox_mfp.conf files ?

12

It took me a while, but I finally managed to implement your solution (my son helped me to understand how it all works :sweat_smile: )

I disabled the sane module in my configuration.nix

  disabledModules = [ "services/hardware/sane.nix" ];

and imported a local version of the module

   imports = [ ./sane.nix ];

and in my local version I did an overrideAttrs

  pkg = (pkgs.sane-backends.override {
    scanSnapDriversUnfree = config.hardware.sane.drivers.scanSnap.enable;
    scanSnapDriversPackage = config.hardware.sane.drivers.scanSnap.package;
  }).overrideAttrs (final: prev: {
    postInstall = ''
      ${prev.postInstall}
      echo "tcp 192.168.1.240" >> $out/etc/sane.d/xerox_mfp.conf
    '';
  });