diff --git a/include/libcamera/framebuffer.h b/include/libcamera/framebuffer.h
index 28307890..9cc1b760 100644
--- a/include/libcamera/framebuffer.h
+++ b/include/libcamera/framebuffer.h
@@ -61,6 +61,7 @@ private:
 	LIBCAMERA_DISABLE_COPY_AND_MOVE(FrameBuffer)
 
 	friend class V4L2VideoDevice; /* Needed to update metadata_. */
+	friend class CPU_ISP;
 
 	std::vector<Plane> planes_;