diff --git a/pylibfdt/libfdt.i b/pylibfdt/libfdt.i
index 415820d..29695bb 100644
--- a/pylibfdt/libfdt.i
+++ b/pylibfdt/libfdt.i
@@ -174,6 +174,17 @@ class Fdt:
         self._fdt = bytearray(data)
         check_err(fdt_check_header(self._fdt));
 
+    def as_bytearray(self):
+        """Get the device tree contents as a bytearray
+
+        This can be passed directly to libfdt functions that access a
+        const void * for the device tree.
+
+        Returns:
+            bytearray containing the device tree
+        """
+        return bytearray(self._fdt)
+
     def subnode_offset(self, parentoffset, name, quiet=()):
         """Get the offset of a named subnode
 
diff --git a/tests/pylibfdt_tests.py b/tests/pylibfdt_tests.py
index 95d911a..0ec0f38 100644
--- a/tests/pylibfdt_tests.py
+++ b/tests/pylibfdt_tests.py
@@ -297,9 +297,10 @@ class PyLibfdtTests(unittest.TestCase):
 
     def testIntegers(self):
         """Check that integers can be passed and returned"""
-        self.assertEquals(0, libfdt.fdt_get_phandle(self.fdt._fdt, 0))
+        self.assertEquals(0, libfdt.fdt_get_phandle(self.fdt.as_bytearray(), 0))
         node2 = self.fdt.path_offset('/subnode@2')
-        self.assertEquals(0x2000, libfdt.fdt_get_phandle(self.fdt._fdt, node2))
+        self.assertEquals(
+                0x2000, libfdt.fdt_get_phandle(self.fdt.as_bytearray(), node2))
 
     def testGetPhandle(self):
         """Test for the get_phandle() method"""