From 2b2a669741df5025854714a9bb4ee61b02aef682 Mon Sep 17 00:00:00 2001
From: Martin Weinelt <hexa@darmstadt.ccc.de>
Date: Thu, 21 Nov 2024 14:56:52 +0100
Subject: [PATCH] nixos/coral: init

Provides a small wrapper to enable support for Coral USB and PCIe
devices.
---
 .../manual/release-notes/rl-2411.section.md   |  2 +
 nixos/modules/hardware/coral.nix              | 38 +++++++++++++++++++
 nixos/modules/module-list.nix                 |  1 +
 3 files changed, 41 insertions(+)
 create mode 100644 nixos/modules/hardware/coral.nix

diff --git a/nixos/doc/manual/release-notes/rl-2411.section.md b/nixos/doc/manual/release-notes/rl-2411.section.md
index e62065775b91..22ae9f241409 100644
--- a/nixos/doc/manual/release-notes/rl-2411.section.md
+++ b/nixos/doc/manual/release-notes/rl-2411.section.md
@@ -85,6 +85,8 @@
 
 ## New Modules {#sec-release-24.11-new-modules}
 
+- [Coral](https://coral.ai/), hardware support for Coral.ai Edge TPU devices. Available as [hardware.coral.usb.enable](#opt-hardware.coral.usb.enable) and [hardware.coral.pcie.enable](#opt-hardware.coral.pcie.enable).
+
 - [Cyrus IMAP](https://github.com/cyrusimap/cyrus-imapd), an email, contacts and calendar server. Available as [services.cyrus-imap](#opt-services.cyrus-imap.enable) service.
 
 - [TaskChampion Sync-Server](https://github.com/GothenburgBitFactory/taskchampion-sync-server), a [Taskwarrior 3](https://taskwarrior.org/docs/upgrade-3/) sync server. Available as [services.taskchampion-sync-server](#opt-services.taskchampion-sync-server.enable).
diff --git a/nixos/modules/hardware/coral.nix b/nixos/modules/hardware/coral.nix
new file mode 100644
index 000000000000..4b0cadfc3cf0
--- /dev/null
+++ b/nixos/modules/hardware/coral.nix
@@ -0,0 +1,38 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  inherit (lib)
+    mkEnableOption
+    mkIf
+    mkMerge
+    ;
+
+  cfg = config.hardware.coral;
+in
+
+{
+  options.hardware.coral = {
+    usb.enable = mkEnableOption "Coral USB support";
+    pcie.enable = mkEnableOption "Coral PCIe support";
+  };
+
+  config = mkMerge [
+    (mkIf (cfg.usb.enable || cfg.pcie.enable) {
+      users.groups.coral = { };
+    })
+    (mkIf cfg.usb.enable {
+      services.udev.packages = with pkgs; [ libedgetpu ];
+    })
+    (mkIf cfg.pcie.enable {
+      boot.extraModulePackages = with config.boot.kernelPackages; [ gasket ];
+      services.udev.extraRules = ''
+        SUBSYSTEM=="apex",MODE="0660",GROUP="coral"
+      '';
+    })
+  ];
+}
diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index cc107eefe505..a1b8f52c0773 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -52,6 +52,7 @@
   ./hardware/bladeRF.nix
   ./hardware/brillo.nix
   ./hardware/ckb-next.nix
+  ./hardware/coral.nix
   ./hardware/corectrl.nix
   ./hardware/cpu/amd-microcode.nix
   ./hardware/cpu/amd-sev.nix