diff --git a/src/libcamera/include/v4l2_subdevice.h b/src/libcamera/include/v4l2_subdevice.h
index 8fd666078985..ffa92100ffbc 100644
--- a/src/libcamera/include/v4l2_subdevice.h
+++ b/src/libcamera/include/v4l2_subdevice.h
@@ -12,6 +12,7 @@
 namespace libcamera {
 
 struct Rectangle;
+class MediaEntity;
 
 struct V4L2SubdeviceFormat {
 	uint32_t mbus_code;