From 4ef82339c9a32548d2432ca71e8aac87abe79777 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rostislav=20Bene=C5=A1?= <r.dee.b.b@gmail.com>
Date: Sun, 7 May 2017 22:27:02 +0200
Subject: [PATCH] nixos/gdm,nvidia: new options to enable GDM on Wayland and
 disabling it for nvidia drivers.

---
 nixos/modules/hardware/video/nvidia.nix             | 6 ++++++
 nixos/modules/services/x11/display-managers/gdm.nix | 9 +++++++++
 2 files changed, 15 insertions(+)

diff --git a/nixos/modules/hardware/video/nvidia.nix b/nixos/modules/hardware/video/nvidia.nix
index 2bad50d65e7a..52f1773e9c45 100644
--- a/nixos/modules/hardware/video/nvidia.nix
+++ b/nixos/modules/hardware/video/nvidia.nix
@@ -40,6 +40,12 @@ in
 {
 
   config = mkIf enabled {
+    assertions = [
+      {
+        assertion = services.xserver.displayManager.gdm.wayland;
+        message = "NVidia drivers don't support wayland";
+      }
+    ];
 
     services.xserver.drivers = singleton
       { name = "nvidia"; modules = [ nvidia_x11.bin ]; libPath = [ nvidia_x11 ]; };
diff --git a/nixos/modules/services/x11/display-managers/gdm.nix b/nixos/modules/services/x11/display-managers/gdm.nix
index b0a3ff1bb753..e68bc816aad2 100644
--- a/nixos/modules/services/x11/display-managers/gdm.nix
+++ b/nixos/modules/services/x11/display-managers/gdm.nix
@@ -64,6 +64,14 @@ in
         };
       };
 
+      wayland = mkOption {
+        default = true;
+        description = ''
+          Allow GDM run on Wayland instead of Xserver
+        '';
+        type = types.bool;
+      };
+
     };
 
   };
@@ -139,6 +147,7 @@ in
     # presented and there's a little delay.
     environment.etc."gdm/custom.conf".text = ''
       [daemon]
+      WaylandEnable=${if cfg.gdm.wayland then "true" else "false"}
       ${optionalString cfg.gdm.autoLogin.enable (
         if cfg.gdm.autoLogin.delay > 0 then ''
           TimedLoginEnable=true