diff --git a/media/mtp/MtpDevice.h b/media/mtp/MtpDevice.h
index b69203e..9b0acbf 100644
--- a/media/mtp/MtpDevice.h
+++ b/media/mtp/MtpDevice.h
@@ -98,7 +98,7 @@
     bool                    readObject(MtpObjectHandle handle,
                                     bool (* callback)(void* data, int offset,
                                             int length, void* clientData),
-                                    int objectSize, void* clientData);
+                                    size_t objectSize, void* clientData);
     bool                    readObject(MtpObjectHandle handle, const char* destPath, int group,
                                     int perm);