logitech (nixos): support module for logitech input devices

nixos/modules/hardware/logitech.nix

@@ -0,0 +1,28 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.hardware.logitech;
+
+in {
+  options.hardware.logitech = {
+    enable = mkEnableOption "Logitech Devices";
+
+    enableGraphical = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Enable graphical support applications.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    environment.systemPackages = [
+      pkgs.ltunify
+    ] ++ lib.optional cfg.enableGraphical pkgs.solaar;
+
+    # ltunifi and solaar both provide udev rules but the most up-to-date have been split
+    # out into a dedicated derivation
+    services.udev.packages = with pkgs; [ logitech-udev-rules ];
+  };
+}

nixos/modules/module-list.nix

@@ -45,6 +45,7 @@
   ./hardware/sensor/iio.nix
   ./hardware/ksm.nix
   ./hardware/ledger.nix
+  ./hardware/logitech.nix
   ./hardware/mcelog.nix
   ./hardware/network/b43.nix
   ./hardware/nitrokey.nix