1 files changed, 44 insertions, 0 deletions
diff --git a/nixos/modules/tasks/scsi-link-power-management.nix b/nixos/modules/tasks/scsi-link-power-management.nix
new file mode 100644
index 00000000000..4ab67aee395
--- /dev/null
+++ b/nixos/modules/tasks/scsi-link-power-management.nix
@@ -0,0 +1,44 @@
+{ config, pkgs, ... }:
+
+with pkgs.lib;
+
+{
+  ###### interface
+
+  options = {
+
+    powerManagement.scsiLinkPolicy = mkOption {
+      default = "";
+      example = "min_power";
+      type = types.uniq types.string;
+      description = ''
+        Configure the SCSI link power management policy. By default,
+        the kernel configures "max_performance".
+      '';
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf (config.powerManagement.scsiLinkPolicy != "") {
+
+    jobs."scsi-link-pm" =
+      { description = "SCSI Link Power Management Policy";
+
+        startOn = "stopped udevtrigger";
+
+        task = true;
+
+        script = ''
+          shopt -s nullglob
+          for x in /sys/class/scsi_host/host*/link_power_management_policy; do
+            echo ${config.powerManagement.scsiLinkPolicy} > $x
+          done
+        '';
+      };
+
+  };
+
+}