diff --git a/components/fatfs/src/ff.c b/components/fatfs/src/ff.c
index 7d2f601d14..2730b2c5ba 100644
--- a/components/fatfs/src/ff.c
+++ b/components/fatfs/src/ff.c
@@ -6240,7 +6240,7 @@ static void putc_bfd (		/* Buffered write with code conversion */
 	WCHAR hs, wc;
 #if FF_LFN_UNICODE == 2
 	DWORD dc;
-	TCHAR *tp;
+	const TCHAR *tp;
 #endif
 #endif
 
@@ -6282,7 +6282,7 @@ static void putc_bfd (		/* Buffered write with code conversion */
 			return;
 		}
 	}
-	tp = (TCHAR*)pb->bs;
+	tp = (const TCHAR*)pb->bs;
 	dc = tchar2uni(&tp);	/* UTF-8 ==> UTF-16 */
 	if (dc == 0xFFFFFFFF) return;
 	wc = (WCHAR)dc;
@@ -6444,7 +6444,7 @@ int f_printf (
 
 	for (;;) {
 		c = *fmt++;
-		if (c == 0) break;			/* End of string */
+		if (c == 0) break;                      /* End of string */
 		if (c != '%') {				/* Non escape character */
 			putc_bfd(&pb, c);
 			continue;