From dc95d6fd776905634d5e7cca7bb35818c6cd0332 Mon Sep 17 00:00:00 2001
From: SebastianStork <git@sstork.dev>
Date: Mon, 9 Mar 2026 17:17:14 +0100
Subject: [PATCH] srv-core: Add fancontrol

---
 hosts/srv-core/hardware.nix | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/hosts/srv-core/hardware.nix b/hosts/srv-core/hardware.nix
index b418ddc..3b0c9c8 100644
--- a/hosts/srv-core/hardware.nix
+++ b/hosts/srv-core/hardware.nix
@@ -42,4 +42,33 @@
       };
     };
   };
+
+  # Ensure pwm2_enable is set to 2 (automatic) before fancontrol starts,
+  # because the IT8613E can't transition 0 -> 1 (manual) directly,
+  # but can do 2 -> 1 which fancontrol requires.
+  systemd.services.fancontrol-pwm-init = {
+    description = "Initialize IT8613E PWM mode for fancontrol";
+    before = [ "fancontrol.service" ];
+    requiredBy = [ "fancontrol.service" ];
+    serviceConfig.Type = "oneshot";
+    script = "echo 2 > /sys/devices/platform/it87.2608/hwmon/hwmon*/pwm2_enable";
+    unitConfig.ConditionPathExists = "/sys/devices/platform/it87.2608";
+  };
+
+  hardware.fancontrol = {
+    enable = true;
+    config = ''
+      INTERVAL=5
+      DEVPATH=hwmon1=devices/platform/coretemp.0 hwmon2=devices/platform/it87.2608
+      DEVNAME=hwmon1=coretemp hwmon2=it8613
+      FCTEMPS=hwmon2/pwm2=hwmon1/temp1_input
+      FCFANS=hwmon2/pwm2=hwmon2/fan2_input
+      MINTEMP=hwmon2/pwm2=70
+      MAXTEMP=hwmon2/pwm2=100
+      MINSTART=hwmon2/pwm2=35
+      MINSTOP=hwmon2/pwm2=25
+      MINPWM=hwmon2/pwm2=0
+      MAXPWM=hwmon2/pwm2=255
+    '';
+  };
 }