diff --git a/drm/DrmDevice.h b/drm/DrmDevice.h
index dfca263..04bfe3c 100644
--- a/drm/DrmDevice.h
+++ b/drm/DrmDevice.h
@@ -96,6 +96,8 @@
     return *mDrmFbImporter.get();
   }
 
+  static auto IsKMSDev(const char *path) -> bool;
+
  private:
   int TryEncoderForDisplay(int display, DrmEncoder *enc);
   int GetProperty(uint32_t obj_id, uint32_t obj_type, const char *prop_name,