many changes

hosts/gpd-win4/modules/steam.nix

@@ -0,0 +1,80 @@
+{ config, lib, pkgs, ... }:
+let
+  # For GPD Win4’s AMD APU, we assume AMD Vulkan drivers:
+  amdPackages = [
+    pkgs.amdvlk
+    pkgs.driversi686Linux.amdvlk
+  ];
+in
+{
+  options.services.steamDeckMode = {
+    enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = "Launch Steam in a ‘Deck-like’ session upon login (auto-logins and starts Steam in gamepad UI mode).";
+    };
+  };
+
+  config = {
+    # Enable Steam and Gamescope
+    programs.gamescope = {
+      enable = true;
+      capSysNice = true;
+    };
+    programs.steam = {
+      enable = true;
+      # The ‘gamescopeSession’ creates a special session for Steam on Wayland
+      gamescopeSession.enable = true;
+    };
+
+    # Add some helpful gaming utilities
+    environment.systemPackages = with pkgs; [
+      mangohud
+      steam-tui
+      steamcmd
+      vulkan-tools
+      vulkan-headers
+      vulkan-loader
+      wlroots
+      libdecor
+      gamemode
+    ];
+
+    # Enable 32-bit support for libraries (often required by Steam)
+    hardware.opengl.enable = true;
+    hardware.opengl.driSupport32Bit = true;
+
+    # Additional AMD drivers if needed
+    hardware.graphics.enable = true;
+    hardware.graphics.enable32Bit = true;
+    hardware.graphics.extraPackages = amdPackages;
+
+    # Example udev rules for Steam Deck controllers, optional
+    environment.etc."udev/rules.d/99-steamdeck-controller.rules".text = ''
+      # Valve Controller devices
+      SUBSYSTEM=="usb", ATTRS{idVendor}=="28de", MODE="0666"
+      KERNEL=="uinput", MODE="0660", GROUP="input", OPTIONS+="static_node=uinput"
+    '';
+
+    # Provide a “Steam Deck Mode” session in the display manager
+    services.xserver.displayManager.session = {
+      "steam-deck-mode" = {
+        name = "Steam Deck Mode";
+        start = ''
+          #!/usr/bin/env bash
+          # On X11, you could also remove or adjust the following env variable if you prefer Wayland
+          export XDG_SESSION_TYPE=x11
+
+          # Fullscreen + close gamescope on exit, then run Steam in gamepad UI
+          exec gamescope -f -e -- steam -gamepadui
+        '';
+      };
+    };
+  }
+  // lib.mkIf config.services.steamDeckMode.enable {
+    # Auto-login to the user of your choice and start in Steam Deck Mode
+    services.xserver.displayManager.autoLogin.enable = true;
+    services.xserver.displayManager.autoLogin.user = "dominik"; # or your preferred user
+    services.xserver.autoRestartXServer = true;
+    services.xserver.displayManager.defaultSession = "steam-deck-mode";
+  };