From 3de04b4681766e6d53cd862b505775ff4bee9836 Mon Sep 17 00:00:00 2001
From: Micah Cowell <micahcowell@gmail.com>
Date: Sun, 15 Feb 2026 14:45:12 -0800
Subject: [PATCH] add no_lfn build tag

---
 fatfs/ffconf.h           |  2 ++
 fatfs/go_fatfs_no_lfn.go | 11 +++++++++++
 2 files changed, 13 insertions(+)
 create mode 100644 fatfs/go_fatfs_no_lfn.go

diff --git a/fatfs/ffconf.h b/fatfs/ffconf.h
index 5c31826..d284cad 100644
--- a/fatfs/ffconf.h
+++ b/fatfs/ffconf.h
@@ -105,7 +105,9 @@
 */
 
 
+#ifndef FF_USE_LFN
 #define FF_USE_LFN      2
+#endif
 #define FF_MAX_LFN      255
 /* The FF_USE_LFN switches the support for LFN (long file name).
 /
diff --git a/fatfs/go_fatfs_no_lfn.go b/fatfs/go_fatfs_no_lfn.go
new file mode 100644
index 0000000..01a7466
--- /dev/null
+++ b/fatfs/go_fatfs_no_lfn.go
@@ -0,0 +1,11 @@
+//go:build no_lfn
+
+package fatfs
+
+// FF_USE_LFN controls long file name (LFN) support in FatFs (default: 2).
+// Using the build tag no_lfn sets FF_USE_LFN=0 which disables LFN and
+// restricts file names to the 8.3 short file name format. It also removes
+// the Unicode conversion tables in ffunicode.c, resulting in ~60KB of flash savings.
+
+// #cgo CFLAGS: -DFF_USE_LFN=0
+import "C"