diff --git a/firmware/target/arm/usb-fw-pp502x.c b/firmware/target/arm/usb-fw-pp502x.c
index f17707c86b..7af699c064 100644
--- a/firmware/target/arm/usb-fw-pp502x.c
+++ b/firmware/target/arm/usb-fw-pp502x.c
@@ -83,7 +83,7 @@ void usb_enable(bool on)
         usb_core_exit();
 }
 
-bool usb_pin_detect(void)
+static bool usb_pin_detect(void)
 {
 #if defined(IPOD_4G) || defined(IPOD_COLOR) \
  || defined(IPOD_MINI) || defined(IPOD_MINI2G)