config_tools: extract virtio device input basic information

Add a new extractor 70-device-classes.py which extracts virtio device
input basic information such as: name and phys.

An example:
<device_classes>
  <inputs>
    <input>
      <name>Power Button</name>
      <phys>LNXPWRBN/button/input0</phys>
    </input>
  <inputs>
</device_classes>

Tracked-On: #6690
Signed-off-by: Kunhui-Li <kunhuix.li@intel.com>

misc/config_tools/board_inspector/board_inspector.py

@@ -102,6 +102,7 @@ def main(board_name, board_xml, args):
         root_node.append(lxml.etree.Element("memory"))
         root_node.append(lxml.etree.Element("ioapics"))
         root_node.append(lxml.etree.Element("devices"))
+        root_node.append(lxml.etree.Element("device-classes"))
 
         extractors_path = os.path.join(script_dir, "extractors")
         extractors = [f for f in os.listdir(extractors_path) if f[:2].isdigit()]

misc/config_tools/board_inspector/extractors/70-device-classes.py

@@ -0,0 +1,42 @@
+# Copyright (C) 2022 Intel Corporation.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+import re, os
+import logging
+from extractors.helpers import add_child, get_node
+
+SYS_DEVICES_CLASS_PATH = "/sys/class/input/"
+
+def get_input_ids():
+    input_ids = list()
+    root_regex = re.compile("input([0-9]+)")
+    for root in filter(lambda x: x.startswith("input"), os.listdir(SYS_DEVICES_CLASS_PATH)):
+        m = root_regex.match(root)
+        if m:
+            input_ids.append(int(m.group(1)))
+    return sorted(input_ids)
+
+def extract_topology(device_classes_node):
+    inputs_node = add_child(device_classes_node, "inputs", None)
+    input_ids = get_input_ids()
+    for id in input_ids:
+        input_node = add_child(inputs_node, "input", None)
+        try:
+            with open("/sys/class/input/input{}/name".format(id), "r") as f:
+                res = f.read().strip()
+                add_child(input_node, "name", res)
+        except Exception as e:
+            logging.warning(f"Failed to read the data of /sys/class/input/input{id}/name: {e}")
+
+        try:
+            with open("/sys/class/input/input{}/phys".format(id), "r") as f:
+                res = f.read().strip()
+                add_child(input_node, "phys", res)
+        except Exception as e:
+            logging.warning(f"Failed to read the data of /sys/class/input/input{id}/phys: {e}")
+
+def extract(args, board_etree):
+    device_classes_node = get_node(board_etree, "//device-classes")
+    extract_topology(device_classes_node)