pylibfdt: Support boolean properties
Boolean properties are unusual in that their presense or absence
indicates the value of the property. This makes them a little painful to
support using the existing getprop() support.
Add new methods to deal with booleans specifically.
Signed-off-by: Simon Glass <sjg@chromium.org>
Message-ID: <20230912182716.248253-1-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
diff --git a/pylibfdt/libfdt.i b/pylibfdt/libfdt.i
index 2361e22..0b50983 100644
--- a/pylibfdt/libfdt.i
+++ b/pylibfdt/libfdt.i
@@ -419,6 +419,35 @@
return pdata
return Property(prop_name, bytearray(pdata[0]))
+ def hasprop(self, nodeoffset, prop_name, quiet=()):
+ """Check if a node has a property
+
+ This can be used to check boolean properties
+
+ Args:
+ nodeoffset: Node offset containing property to check
+ prop_name: Name of property to check
+ quiet: Errors to ignore (empty to raise on all errors). Note that
+ NOTFOUND is added internally by this function so need not be
+ provided
+
+ Returns:
+ True if the property exists in the node, else False. If an error
+ other than -NOTFOUND is returned by fdt_getprop() then the error
+ is return (-ve integer)
+
+ Raises:
+ FdtError if any error occurs other than NOTFOUND (e.g. the
+ nodeoffset is invalid)
+ """
+ pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
+ quiet + (NOTFOUND,))
+ if isinstance(pdata, (int)):
+ if pdata == -NOTFOUND:
+ return False
+ return pdata
+ return True
+
def get_phandle(self, nodeoffset):
"""Get the phandle of a node
@@ -605,6 +634,32 @@
return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name, val,
len(val)), quiet)
+ def setprop_bool(self, nodeoffset, prop_name, val, quiet=()):
+ """Set the boolean value of a property
+
+ Either:
+ adds the property if not already present; or
+ deletes the property if present
+
+ Args:
+ nodeoffset: Node offset containing the property to create/delete
+ prop_name: Name of property
+ val: Boolean value to write (i.e. True or False)
+ quiet: Errors to ignore (empty to raise on all errors)
+
+ Returns:
+ Error code, or 0 if OK
+
+ Raises:
+ FdtException if no parent found or other error occurs
+ """
+ exists = self.hasprop(nodeoffset, prop_name, quiet)
+ if val != exists:
+ if val:
+ return self.setprop(nodeoffset, prop_name, b'', quiet=quiet)
+ else:
+ return self.delprop(nodeoffset, prop_name, quiet=quiet)
+
def setprop_u32(self, nodeoffset, prop_name, val, quiet=()):
"""Set the value of a property
diff --git a/tests/pylibfdt_tests.py b/tests/pylibfdt_tests.py
index 34c2764..a4f73ed 100644
--- a/tests/pylibfdt_tests.py
+++ b/tests/pylibfdt_tests.py
@@ -496,6 +496,39 @@
self.assertEqual(TEST_STRING_3,
self.fdt.getprop(node, prop).as_str())
+ def testHasProp(self):
+ """Test that we can check if a node has a property"""
+ node = 0
+ self.assertFalse(self.fdt2.hasprop(node, 'missing'))
+ self.assertTrue(self.fdt2.hasprop(node, 'prop-bool'))
+
+ # Test a property with a non-empty value
+ self.assertTrue(self.fdt2.hasprop(node, 'prop-uint64'))
+
+ def testSetPropBool(self):
+ """Test that we can update and create boolean properties"""
+ node = 0
+ prop = 'prop-bool'
+
+ # Make some space and then try setting a new boolean property
+ self.fdt.resize(self.fdt.totalsize() + 50)
+ self.fdt.hasprop(node, 'missing')
+ self.fdt.setprop_bool(node, 'missing', True)
+ self.assertTrue(self.fdt.hasprop(node, 'missing'))
+
+ # Trying toggling an existing boolean property. Do each operation twice
+ # to make sure that the behaviour is correct when setting the property
+ # to the same value.
+ self.assertTrue(self.fdt2.hasprop(node, prop))
+ self.fdt2.setprop_bool(node, prop, False)
+ self.assertFalse(self.fdt2.hasprop(node, prop))
+ self.fdt2.setprop_bool(node, prop, False)
+ self.assertFalse(self.fdt2.hasprop(node, prop))
+ self.fdt2.setprop_bool(node, prop, True)
+ self.assertTrue(self.fdt2.hasprop(node, prop))
+ self.fdt2.setprop_bool(node, prop, True)
+ self.assertTrue(self.fdt2.hasprop(node, prop))
+
def testSetName(self):
"""Test that we can update a node name"""
node = self.fdt.path_offset('/subnode@1')
diff --git a/tests/test_props.dts b/tests/test_props.dts
index 5089023..09be197 100644
--- a/tests/test_props.dts
+++ b/tests/test_props.dts
@@ -12,4 +12,5 @@
prop-uint32-array = <0x1>, <0x98765432>, <0xdeadbeef>;
prop-int64-array = /bits/ 64 <0x100000000 0xfffffffffffffffe>;
prop-uint64-array = /bits/ 64 <0x100000000 0x1>;
+ prop-bool;
};
