From 745dd440719439197ee7821ad61fff1de557b55d Mon Sep 17 00:00:00 2001
From: Vincent Breitmoser <look@my.amazin.horse>
Date: Sat, 14 Aug 2021 17:17:21 +0200
Subject: [PATCH] raspberry-pi/4: Add audio option

---
 raspberry-pi/4/audio.nix   | 40 ++++++++++++++++++++++++++++++++++++++
 raspberry-pi/4/default.nix |  1 +
 2 files changed, 41 insertions(+)
 create mode 100644 raspberry-pi/4/audio.nix

diff --git a/raspberry-pi/4/audio.nix b/raspberry-pi/4/audio.nix
new file mode 100644
index 0000000..3ee189a
--- /dev/null
+++ b/raspberry-pi/4/audio.nix
@@ -0,0 +1,40 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.hardware.raspberry-pi."4".audio;
+in
+{
+  options.hardware = {
+    raspberry-pi."4".audio = {
+      enable = lib.mkEnableOption ''
+        configuration for audio
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    hardware.deviceTree = {
+      overlays = [
+        # Equivalent to dtparam=audio=on
+        {
+          name = "audio-on-overlay";
+          dtsText = ''
+            /dts-v1/;
+            /plugin/;
+            / {
+              compatible = "brcm,bcm2711";
+              fragment@0 {
+                target = <&audio>;
+
+                __overlay__ {
+                  status = "okay";
+                };
+              };
+            };
+          '';
+        }
+      ];
+    };
+  };
+}
+
diff --git a/raspberry-pi/4/default.nix b/raspberry-pi/4/default.nix
index 3699190..2fe97e1 100644
--- a/raspberry-pi/4/default.nix
+++ b/raspberry-pi/4/default.nix
@@ -2,6 +2,7 @@
 
 {
   imports = [
+    ./audio.nix
     ./dwc2.nix
     ./modesetting.nix
     ./poe-hat.nix