nixos/linux-enable-ir-emitter: init

nixos/doc/manual/release-notes/rl-2605.section.md

@@ -38,6 +38,8 @@
 
 - [Howdy](https://github.com/boltgolt/howdy), a Windows Hello™ style facial authentication program for Linux.
 
+- [linux-enable-ir-emitter](https://github.com/EmixamPP/linux-enable-ir-emitter), a tool used to set up IR cameras, used with Howdy.
+
 - [udp-over-tcp](https://github.com/mullvad/udp-over-tcp), a tunnel for proxying UDP traffic over a TCP stream. Available as `services.udp-over-tcp`.
 
 - [Komodo Periphery](https://github.com/moghtech/komodo), a multi-server Docker and Git deployment agent by Komodo. Available as [services.komodo-periphery](#opt-services.komodo-periphery.enable).

nixos/modules/module-list.nix

@@ -878,6 +878,7 @@
   ./services/misc/languagetool.nix
   ./services/misc/leaps.nix
   ./services/misc/lifecycled.nix
+  ./services/misc/linux-enable-ir-emitter.nix
   ./services/misc/litellm.nix
   ./services/misc/llama-cpp.nix
   ./services/misc/local-content-share.nix

nixos/modules/services/misc/linux-enable-ir-emitter.nix

@@ -0,0 +1,71 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.services.linux-enable-ir-emitter;
+in
+{
+  options = {
+    services.linux-enable-ir-emitter = {
+      enable = lib.mkEnableOption "" // {
+        description = ''
+          Whether to enable IR emitter hardware. Designed to be used with the
+          Howdy facial authentication. After enabling the service, configure
+          the emitter with `sudo linux-enable-ir-emitter configure`.
+        '';
+      };
+
+      package = lib.mkPackageOption pkgs "linux-enable-ir-emitter" { } // {
+        description = ''
+          Package to use for the Linux Enable IR Emitter service.
+        '';
+      };
+
+      device = lib.mkOption {
+        type = lib.types.str;
+        default = "video2";
+        description = ''
+          IR camera device to depend on. For example, for `/dev/video2`
+          the value would be `video2`. Find this with the command
+          {command}`realpath /dev/v4l/by-path/<generated-driver-name>`.
+        '';
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    environment.systemPackages = [ cfg.package ];
+
+    # https://github.com/EmixamPP/linux-enable-ir-emitter/blob/7e3a6527ef2efccabaeefc5a93c792628325a8db/sources/systemd/linux-enable-ir-emitter.service
+    systemd.services.linux-enable-ir-emitter =
+      let
+        targets = [
+          "suspend.target"
+          "sleep.target"
+          "hybrid-sleep.target"
+          "hibernate.target"
+          "suspend-then-hibernate.target"
+        ];
+      in
+      {
+        description = "Enable the infrared emitter";
+        # Added to match
+        # https://github.com/EmixamPP/linux-enable-ir-emitter/blob/6.1.2/boot_service/systemd/linux-enable-ir-emitter.service
+        # Prevents the program fail to detect the IR camera until a service
+        # restart.
+        preStart = ''
+          ${pkgs.kmod}/bin/modprobe uvcvideo
+          sleep 1
+        '';
+        script = "${lib.getExe cfg.package} --verbose run";
+        serviceConfig.StateDirectory = "linux-enable-ir-emitter";
+        serviceConfig.LogsDirectory = "linux-enable-ir-emitter";
+
+        wantedBy = targets ++ [ "multi-user.target" ];
+        after = targets ++ [ "dev-${cfg.device}.device" ];
+      };
+  };
+}