Merge pull request #14 from sifive/create-node-from-string

Create node from string

pydevicetree/ast/node.py

@@ -103,6 +103,20 @@ def __eq__(self, other) -> bool:
     def __hash__(self):
         return hash((self.name, self.address))
 
+    @staticmethod
+    def from_dts(source: str) -> 'Node':
+        """Create a node from Devicetree Source"""
+        # pylint: disable=import-outside-toplevel,cyclic-import
+        from pydevicetree.source import parseNode
+        return parseNode(source)
+
+    def add_child(self, node: 'Node', merge: bool = True):
+        """Add a child node and merge it into the tree"""
+        node.parent = self
+        self.children.append(node)
+        if merge:
+            self.merge_tree()
+
     def to_dts(self, level: int = 0) -> str:
         """Format the subtree starting at the node as Devicetree Source"""
         out = ""
@@ -195,7 +209,7 @@ def __get_child_by_handle(self, handle: str) -> Optional['Node']:
         """Get a child node by name or name and unit address"""
         if '@' in handle:
             name, addr_s = handle.split('@')
-            address = int(addr_s)
+            address = int(addr_s, base=16)
             nodes = list(filter(lambda n: n.name == name and n.address == address, self.children))
         else:
             name = handle

pydevicetree/source/__init__.py

@@ -2,4 +2,4 @@
 # Copyright (c) 2019 SiFive Inc.
 # SPDX-License-Identifier: Apache-2.0
 
-from pydevicetree.source.parser import parseTree
+from pydevicetree.source.parser import parseTree, parseNode

pydevicetree/source/parser.py

@@ -144,6 +144,10 @@ def parseTree(dts, pwd="", followIncludes=False):
     """Parses a string into a full Devicetree"""
     return Devicetree(parseElements(dts, pwd, followIncludes))
 
+def parseNode(dts):
+    """Parses a string into a Devictreee Node"""
+    return grammar.node_definition.parseString(dts)[0]
+
 if __name__ == "__main__":
     import sys
     if len(sys.argv) > 1:

tests/test_devicetree.py

@@ -137,5 +137,30 @@ def func(values):
         self.assertEqual(cpu.get_path(), "/cpus/cpu@0")
         self.assertEqual(cpu.get_field("reg"), 0)
 
+    def test_node_from_dts(self):
+        node = Node.from_dts("uart0: uart@10013000 { compatible = \"sifive,uart0\"; };")
+
+        self.assertEqual(type(node), Node)
+        self.assertEqual(node.label, "uart0")
+        self.assertEqual(node.name, "uart")
+        self.assertEqual(node.address, 0x10013000)
+        self.assertEqual(node.get_field("compatible"), "sifive,uart0")
+
+    def test_add_child(self):
+        tree = parseTree(self.source)
+
+        new_node = Node.from_dts("uart0: uart@10013000 { compatible = \"sifive,uart0\"; };")
+
+        soc = tree.get_by_path("/soc")
+        soc.add_child(new_node)
+
+        uart = tree.get_by_path("/soc/uart@10013000")
+        self.assertEqual(type(uart), Node)
+        self.assertEqual(uart.label, "uart0")
+        self.assertEqual(uart.name, "uart")
+        self.assertEqual(uart.address, 0x10013000)
+        self.assertEqual(uart.get_field("compatible"), "sifive,uart0")
+
+
 if __name__ == "__main__":
     unittest.main()