diff --git a/ChangeLog b/ChangeLog
index f41da2c2..36ea7f2e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2006-07-19 Joerg Wunsch <j@uriah.heep.sax.de>
+
+	* stk500v2.c: Hide stk500v2_set_sck_period_mk2() behind an #if
+	defined(HAVE_LIBUSB) as it is only used there (for the AVRISP
+	mkII).
+
 2006-07-17 Joerg Wunsch <j@uriah.heep.sax.de>
 
 	* stk500v2.c: Fix all bugs in stk500pp.  Eliminate pagebuf, and
diff --git a/stk500v2.c b/stk500v2.c
index e5e7efc3..b53ffef9 100644
--- a/stk500v2.c
+++ b/stk500v2.c
@@ -95,9 +95,12 @@ static void stk500v2_print_parms1(PROGRAMMER * pgm, char * p);
 static int stk500v2_is_page_empty(unsigned int address, int page_size,
                                   const unsigned char *buf);
 
-static int stk500v2_set_sck_period_mk2(PROGRAMMER * pgm, double v);
 static unsigned int stk500v2_mode_for_pagesize(unsigned int pagesize);
 
+#if defined(HAVE_LIBUSB)
+static int stk500v2_set_sck_period_mk2(PROGRAMMER * pgm, double v);
+#endif
+
 static int stk500v2_send_mk2(PROGRAMMER * pgm, unsigned char * data, size_t len)
 {
   if (serial_send(pgm->fd, data, len) != 0) {
@@ -1468,6 +1471,7 @@ double avrispmkIIfreqs[] = {
 	65.0, 61.9, 59.0, 56.3, 53.6, 51.1
 };
 
+#if defined(HAVE_LIBUSB)
 static int stk500v2_set_sck_period_mk2(PROGRAMMER * pgm, double v)
 {
   int i;
@@ -1482,6 +1486,7 @@ static int stk500v2_set_sck_period_mk2(PROGRAMMER * pgm, double v)
 
   return stk500v2_setparm(pgm, PARAM_SCK_DURATION, i);
 }
+#endif /* HAVE_LIBUSB */
 
 /*
  * Return the "mode" value for the parallel and HVSP modes that