libinput: Add tappingButtonMap option (#189612)

Co-authored-by: Sandro <sandro.jaeckel@gmail.com>

nixos/modules/services/x11/hardware/libinput.nix

@@ -156,6 +156,14 @@ let cfg = config.services.xserver.libinput;
           '';
       };
 
+      tappingButtonMap = mkOption {
+        type = types.nullOr (types.enum [ "lrm" "lmr" ]);
+        default = null;
+        description = lib.mdDoc ''
+          Set the button mapping for 1/2/3-finger taps to left/right/middle or left/middle/right, respectively.
+        '';
+      };
+
       tappingDragLock = mkOption {
         type = types.bool;
         default = true;
@@ -220,6 +228,7 @@ let cfg = config.services.xserver.libinput;
       Option "HorizontalScrolling" "${xorgBool cfg.${deviceType}.horizontalScrolling}"
       Option "SendEventsMode" "${cfg.${deviceType}.sendEventsMode}"
       Option "Tapping" "${xorgBool cfg.${deviceType}.tapping}"
+      ${optionalString (cfg.${deviceType}.tappingButtonMap != null) ''Option "TappingButtonMap" "${cfg.${deviceType}.tappingButtonMap}"''}
       Option "TappingDragLock" "${xorgBool cfg.${deviceType}.tappingDragLock}"
       Option "DisableWhileTyping" "${xorgBool cfg.${deviceType}.disableWhileTyping}"
       ${cfg.${deviceType}.additionalOptions}
@@ -241,6 +250,7 @@ in {
       "horizontalScrolling"
       "sendEventsMode"
       "tapping"
+      "tappingButtonMap"
       "tappingDragLock"
       "transformationMatrix"
       "disableWhileTyping"