diff --git a/raspberry-pi/4/apply-overlays-dtmerge.nix b/raspberry-pi/4/apply-overlays-dtmerge.nix
index 0d17bb8..8a325ab 100644
--- a/raspberry-pi/4/apply-overlays-dtmerge.nix
+++ b/raspberry-pi/4/apply-overlays-dtmerge.nix
@@ -1,9 +1,11 @@
+# modification of nixpkgs deviceTree.applyOverlays to resolve https://github.com/NixOS/nixpkgs/issues/125354
+# https://github.com/NixOS/nixpkgs/blob/master/pkgs/os-specific/linux/device-tree/default.nix
 { lib, pkgs, stdenvNoCC, dtc, libraspberrypi }:
 
 with lib; {
   applyOverlays = (base: overlays': stdenvNoCC.mkDerivation {
     name = "device-tree-overlays";
-    nativeBuildInputs = [ dtc ];
+    nativeBuildInputs = [ dtc libraspberrypi ];
     buildCommand = let
       overlays = toList overlays';
     in ''
diff --git a/raspberry-pi/4/pkgs-overlays.nix b/raspberry-pi/4/pkgs-overlays.nix
index 4b3c16d..c290d2a 100644
--- a/raspberry-pi/4/pkgs-overlays.nix
+++ b/raspberry-pi/4/pkgs-overlays.nix
@@ -1,17 +1,15 @@
 { config, lib, pkgs, modulesPath, ... }:
 let
-  callPackage = path: overrides:
-    let f = import path;
-    in f ((builtins.intersectAttrs (builtins.functionArgs f) pkgs) // overrides);
   cfg = config.hardware.raspberry-pi."4".apply-overlays-dtmerge;
   dt_ao_overlay = (final: prev: {
-    deviceTree.applyOverlays = (prev.callPackage ./apply-overlays-dtmerge.nix { }).applyOverlays;
+    deviceTree.applyOverlays = (prev.callPackage ./apply-overlays-dtmerge.nix { })
   });
 in {
   options.hardware = {
     raspberry-pi."4".apply-overlays-dtmerge = {
       enable = lib.mkEnableOption ''
         replace deviceTree.applyOverlays implementation to use dtmerge from libraspberrypi.
+        this can resolve issues with applying dtbs for the pi.
       '';
     };
   };