diff --git a/tools/patman/gitutil.py b/tools/patman/gitutil.py
index 5189840..29444bf 100644
--- a/tools/patman/gitutil.py
+++ b/tools/patman/gitutil.py
@@ -261,8 +261,10 @@
     Args:
         start: Commit to start from: 0=HEAD, 1=next one, etc.
         count: number of commits to include
+        ignore_binary: Don't generate patches for binary files
+        series: Series object for this series (set of patches)
     Return:
-        Filename of cover letter
+        Filename of cover letter (None if none)
         List of filenames of patch files
     """
     if series.get('version'):