Trackpoint scrolling on T450s et al

1 files changed, 31 insertions, 17 deletions

diff --git a/nixos/modules/tasks/trackpoint.nix b/nixos/modules/tasks/trackpoint.nix
index 778cdc5d30d..bd340869d69 100644
--- a/nixos/modules/tasks/trackpoint.nix
+++ b/nixos/modules/tasks/trackpoint.nix
@@ -45,6 +45,16 @@ with lib;
         '';
       };
 
+      fakeButtons = mkOption {
+        default = false;
+        type = types.bool;
+        description = ''
+          Switch to "bare" PS/2 mouse support in case Trackpoint buttons are not recognized
+          properly. This can happen for example on models like the L430, T450, T450s, on
+          which the Trackpoint buttons are actually a part of the Synaptics touchpad.
+        '';
+      };
+
     };
 
   };
@@ -52,11 +62,13 @@ with lib;
 
   ###### implementation
 
-  config = mkMerge [
-    (mkIf config.hardware.trackpoint.enable {
+  config =
+  let cfg = config.hardware.trackpoint; in
+  mkMerge [
+    (mkIf cfg.enable {
       services.udev.extraRules =
       ''
-        ACTION=="add|change", SUBSYSTEM=="input", ATTR{name}=="TPPS/2 IBM TrackPoint", ATTR{device/speed}="${toString config.hardware.trackpoint.speed}", ATTR{device/sensitivity}="${toString config.hardware.trackpoint.sensitivity}"
+        ACTION=="add|change", SUBSYSTEM=="input", ATTR{name}=="TPPS/2 IBM TrackPoint", ATTR{device/speed}="${toString cfg.speed}", ATTR{device/sensitivity}="${toString cfg.sensitivity}"
       '';
 
       system.activationScripts.trackpoint =
@@ -65,20 +77,22 @@ with lib;
         '';
     })
 
-    (mkIf config.hardware.trackpoint.emulateWheel {
-      services.xserver.config =
-        ''
-          Section "InputClass"
-            Identifier "Trackpoint Wheel Emulation"
-            MatchProduct "Elantech PS/2 TrackPoint|TPPS/2 IBM TrackPoint|DualPoint Stick|Synaptics Inc. Composite TouchPad / TrackPoint|ThinkPad USB Keyboard with TrackPoint|USB Trackpoint pointing device|Composite TouchPad / TrackPoint"
-            MatchDevicePath "/dev/input/event*"
-            Option "EmulateWheel" "true"
-            Option "EmulateWheelButton" "2"
-            Option "Emulate3Buttons" "false"
-            Option "XAxisMapping" "6 7"
-            Option "YAxisMapping" "4 5"
-            EndSection
-        '';
+    (mkIf (cfg.emulateWheel) {
+      services.xserver.inputClassSections =
+        [''
+        Identifier "Trackpoint Wheel Emulation"
+          MatchProduct "${if cfg.fakeButtons then "PS/2 Generic Mouse" else "Elantech PS/2 TrackPoint|TPPS/2 IBM TrackPoint|DualPoint Stick|Synaptics Inc. Composite TouchPad / TrackPoint|ThinkPad USB Keyboard with TrackPoint|USB Trackpoint pointing device|Composite TouchPad / TrackPoint"}"
+          MatchDevicePath "/dev/input/event*"
+          Option "EmulateWheel" "true"
+          Option "EmulateWheelButton" "2"
+          Option "Emulate3Buttons" "false"
+          Option "XAxisMapping" "6 7"
+          Option "YAxisMapping" "4 5"
+        ''];
+    })
+
+    (mkIf cfg.fakeButtons {
+      boot.extraModprobeConfig = "options psmouse proto=bare";
     })
   ];
 }