diff --git a/include/libdivecomputer/custom_serial.h b/include/libdivecomputer/custom_serial.h
index a52d49b..a27d519 100644
--- a/include/libdivecomputer/custom_serial.h
+++ b/include/libdivecomputer/custom_serial.h
@@ -44,6 +44,7 @@ typedef struct dc_serial_operations_t
 	int (*flush) (serial_t *device, int queue);
 	int (*get_received) (serial_t *device);
 	int (*get_transmitted) (serial_t *device);
+	int (*set_timeout) (serial_t *device, long timeout);
 } dc_serial_operations_t;
 
 typedef struct dc_serial_t {
diff --git a/src/custom_serial.c b/src/custom_serial.c
index 6e024b2..a6af432 100644
--- a/src/custom_serial.c
+++ b/src/custom_serial.c
@@ -32,7 +32,8 @@ const dc_serial_operations_t native_serial_ops = {
 	.write = serial_write,
 	.flush = serial_flush,
 	.get_received = serial_get_received,
-	.get_transmitted = serial_get_transmitted
+	.get_transmitted = serial_get_transmitted,
+	.set_timeout = serial_set_timeout
 };