dtoc: Move BytesToValue() out of the Prop class

This method does not actually use any members of the Prop class. Move it
out of the class so that it is easier to add unit tests.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/dtoc/fdt.py

@@ -29,6 +29,57 @@ def CheckErr(errnum, msg):
         raise ValueError('Error %d: %s: %s' %
             (errnum, libfdt.fdt_strerror(errnum), msg))
 
+
+def BytesToValue(bytes):
+    """Converts a string of bytes into a type and value
+
+    Args:
+        A string containing bytes
+
+    Return:
+        A tuple:
+            Type of data
+            Data, either a single element or a list of elements. Each element
+            is one of:
+                TYPE_STRING: string value from the property
+                TYPE_INT: a byte-swapped integer stored as a 4-byte string
+                TYPE_BYTE: a byte stored as a single-byte string
+    """
+    bytes = str(bytes)
+    size = len(bytes)
+    strings = bytes.split('\0')
+    is_string = True
+    count = len(strings) - 1
+    if count > 0 and not strings[-1]:
+        for string in strings[:-1]:
+            if not string:
+                is_string = False
+                break
+            for ch in string:
+                if ch < ' ' or ch > '~':
+                    is_string = False
+                    break
+    else:
+        is_string = False
+    if is_string:
+        if count == 1:
+            return TYPE_STRING, strings[0]
+        else:
+            return TYPE_STRING, strings[:-1]
+    if size % 4:
+        if size == 1:
+            return TYPE_BYTE, bytes[0]
+        else:
+            return TYPE_BYTE, list(bytes)
+    val = []
+    for i in range(0, size, 4):
+        val.append(bytes[i:i + 4])
+    if size == 4:
+        return TYPE_INT, val[0]
+    else:
+        return TYPE_INT, val
+
+
 class Prop:
     """A device tree property
 
@@ -49,7 +100,7 @@ class Prop:
             self.type = TYPE_BOOL
             self.value = True
             return
-        self.type, self.value = self.BytesToValue(bytes)
+        self.type, self.value = BytesToValue(bytes)
 
     def RefreshOffset(self, poffset):
         self._offset = poffset
@@ -88,55 +139,6 @@ class Prop:
             while len(self.value) < len(newprop.value):
                 self.value.append(val)
 
-    def BytesToValue(self, bytes):
-        """Converts a string of bytes into a type and value
-
-        Args:
-            A string containing bytes
-
-        Return:
-            A tuple:
-                Type of data
-                Data, either a single element or a list of elements. Each element
-                is one of:
-                    TYPE_STRING: string value from the property
-                    TYPE_INT: a byte-swapped integer stored as a 4-byte string
-                    TYPE_BYTE: a byte stored as a single-byte string
-        """
-        bytes = str(bytes)
-        size = len(bytes)
-        strings = bytes.split('\0')
-        is_string = True
-        count = len(strings) - 1
-        if count > 0 and not strings[-1]:
-            for string in strings[:-1]:
-                if not string:
-                    is_string = False
-                    break
-                for ch in string:
-                    if ch < ' ' or ch > '~':
-                        is_string = False
-                        break
-        else:
-            is_string = False
-        if is_string:
-            if count == 1:
-                return TYPE_STRING, strings[0]
-            else:
-                return TYPE_STRING, strings[:-1]
-        if size % 4:
-            if size == 1:
-                return TYPE_BYTE, bytes[0]
-            else:
-                return TYPE_BYTE, list(bytes)
-        val = []
-        for i in range(0, size, 4):
-            val.append(bytes[i:i + 4])
-        if size == 4:
-            return TYPE_INT, val[0]
-        else:
-            return TYPE_INT, val
-
     @classmethod
     def GetEmpty(self, type):
         """Get an empty / zero value of the given type
@@ -183,7 +185,7 @@ class Prop:
             bytes: New property value to set
         """
         self.bytes = str(bytes)
-        self.type, self.value = self.BytesToValue(bytes)
+        self.type, self.value = BytesToValue(bytes)
         self.dirty = True
 
     def Sync(self, auto_resize=False):