diff --git a/artiq/dashboard/waveform.py b/artiq/dashboard/waveform.py
index 647154e92..9bde2da3b 100644
--- a/artiq/dashboard/waveform.py
+++ b/artiq/dashboard/waveform.py
@@ -445,27 +445,27 @@ class _WaveformView(QtWidgets.QWidget):
         self._model.rowsInserted.connect(self.onInsert)
         self._model.rowsRemoved.connect(self.onRemove)
         self._model.rowsMoved.connect(self.onMove)
-    
+
     def onDataChange(self, top, bottom, roles):
         first = top.row()
         last = bottom.row()
         for i in range(first, last + 1):
             data = self._model.data(self._model.index(i, 2))
             self._splitter.widget(i).onDataChange(data)
-    
+
     def onInsert(self, parent, first, last):
         for i in range(first, last + 1):
             w = self._create_waveform(self.index(i, 0))
             self.splitter.insertWidget(i, w)
         self._resize()
-    
+
     def onRemove(self, parent, first, last):
         for i in reversed(range(first, last + 1)):
             w = self.splitter.widget(i)
             w.deleteLater()
         self.splitter.refresh()
         self._resize()
-    
+
     def onMove(self, src_parent, src_start, src_end, dest_parent, dest_row):
         w = self.splitter.widget(src_start)
         self.splitter.insertWidget(dest_row, w)
@@ -492,15 +492,15 @@ class _WaveformModel(QtCore.QAbstractTableModel):
         self.backing_struct = []
         self.headers = ["name", "type", "width", "data"]
         QtCore.QAbstractTableModel.__init__(self)
-    
+
     def rowCount(self):
         return len(self.backing_struct)
 
     def columnCount(self):
         return len(self.headers)
-    
+
     def data(self, index, role=QtCore.Qt.DisplayRole):
-        if index.isValid(): 
+        if index.isValid():
             return self.backing_struct[index.row()][index.col()]
         return None
 
@@ -521,12 +521,12 @@ class _WaveformModel(QtCore.QAbstractTableModel):
         self.backing_struct.insert(dest, self.backing_struct.pop(src))
         self.endMoveRows()
 
-    def update_data(self, waveform_data): 
+    def update_data(self, waveform_data):
         for i in range(len(self.backing_struct)):
             name = self.data(self.index(i, 0))
             if name in waveform_data:
-                self.backing_struct[i][3] = waveform_data[name] 
-        self.dataChanged.emit(self.index(0, 0), 
+                self.backing_struct[i][3] = waveform_data[name]
+        self.dataChanged.emit(self.index(0, 0),
                               self.index(len(self.backing_struct)-1, len(self.headers)))