diff --git a/firmware/ice40-riscv/icE1usb/gps.h b/firmware/ice40-riscv/icE1usb/gps.h
new file mode 100644
index 0000000..57ef271
--- /dev/null
+++ b/firmware/ice40-riscv/icE1usb/gps.h
@@ -0,0 +1,23 @@
+/*
+ * gps.h
+ *
+ * Copyright (C) 2019-2022  Sylvain Munaut <tnt@246tNt.com>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include <stdbool.h>
+
+enum gps_antenna_state {
+	ANT_UNKNOWN = 0,
+	ANT_OK,
+	ANT_OPEN,
+	ANT_SHORT
+};
+
+bool gps_has_valid_fix(void);
+enum gps_antenna_state gps_antenna_status(void);
+
+void gps_poll(void);
+void gps_init(void);