chore: add i2c kernel module and group configuration

hosts/common/default.nix

@@ -9,6 +9,7 @@
   imports = [ ./users/thiago/default.nix ];
 
   boot.loader.systemd-boot.enable = true;
+  boot.kernelModules = [ "i2c-dev" ];
 
   nixpkgs.overlays = [
     (final: prev: {
@@ -105,10 +106,15 @@
     # xserver.displayManager.sessionCommands =
     #   "${pkgs.xorg.xmodmap}/bin/xmodmap -e 'keycode 64 = Alt_L'";
 
-    udev.packages = [
-      pkgs.libwacom
-      pkgs.nitrokey-udev-rules
-    ];
+    udev = {
+      packages = [
+        pkgs.libwacom
+        pkgs.nitrokey-udev-rules
+      ];
+      extraRules = ''
+        KERNEL=="i2c-[0-9]*", GROUP="i2c", MODE="0660"
+      '';
+    };
   };
 
   # hardware = {
@@ -126,6 +132,7 @@
   #   };
   # };
   users.groups.scard = { };
+  users.groups.i2c = { };
 
   time.timeZone = "America/Sao_Paulo";