From f5bf638e5f13f92ee3eb3f130469d697cce62b75 Mon Sep 17 00:00:00 2001
From: Jure Varlec <jure@varlec.si>
Date: Sun, 30 Apr 2023 16:13:23 +0200
Subject: [PATCH] nixos/fstrim: fix overriding the timer interval

The OnCalendar systemd setting is additive. To clear the setting defined
by the pre-existing unit file, it has to be set first to an empty
string, then to the desired value.

(cherry picked from commit 44438e0dcdf800809e1bf1bed78dea90bb35037a)
---
 nixos/modules/services/misc/fstrim.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nixos/modules/services/misc/fstrim.nix b/nixos/modules/services/misc/fstrim.nix
index 36b5f9c8cca1..55fb24e29272 100644
--- a/nixos/modules/services/misc/fstrim.nix
+++ b/nixos/modules/services/misc/fstrim.nix
@@ -34,7 +34,7 @@ in {
 
     systemd.timers.fstrim = {
       timerConfig = {
-        OnCalendar = cfg.interval;
+        OnCalendar = [ "" cfg.interval ];
       };
       wantedBy = [ "timers.target" ];
     };