intel: send vsc INTEL_DDC_CONFIG_WRITE

This VSC enable host-initiated role-switching after connection.

Implement this VSC in a driver fashion.

Test: avatar security_test with the Bluetooth Dongle Intel BE200

bumble/drivers/__init__.py

@@ -25,7 +25,7 @@ import pathlib
 import platform
 from typing import Dict, Iterable, Optional, Type, TYPE_CHECKING
 
-from . import rtk
+from . import rtk, intel
 from .common import Driver
 
 if TYPE_CHECKING:
@@ -45,7 +45,7 @@ async def get_driver_for_host(host: Host) -> Optional[Driver]:
     found.
     If a "driver" HCI metadata entry is present, only that driver class will be probed.
     """
-    driver_classes: Dict[str, Type[Driver]] = {"rtk": rtk.Driver}
+    driver_classes: Dict[str, Type[Driver]] = {"rtk": rtk.Driver, "intel": intel.Driver}
     probe_list: Iterable[str]
     if driver_name := host.hci_metadata.get("driver"):
         # Only probe a single driver

bumble/drivers/intel.py

@@ -0,0 +1,66 @@
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# -----------------------------------------------------------------------------
+# Imports
+# -----------------------------------------------------------------------------
+import logging
+
+from bumble.drivers import common
+from bumble.hci import (
+    hci_vendor_command_op_code,  # type: ignore
+    HCI_Command,
+    HCI_Reset_Command,
+)
+
+# -----------------------------------------------------------------------------
+# Logging
+# -----------------------------------------------------------------------------
+logger = logging.getLogger(__name__)
+
+# -----------------------------------------------------------------------------
+# HCI Commands
+# -----------------------------------------------------------------------------
+HCI_INTEL_DDC_CONFIG_WRITE_COMMAND = hci_vendor_command_op_code(0xFC8B)  # type: ignore
+HCI_INTEL_DDC_CONFIG_WRITE_PAYLOAD = [0x03, 0xE4, 0x02, 0x00]
+
+HCI_Command.register_commands(globals())
+
+
+@HCI_Command.command(  # type: ignore
+    fields=[("params", "*")],
+    return_parameters_fields=[
+        ("params", "*"),
+    ],
+)
+class Hci_Intel_DDC_Config_Write_Command(HCI_Command):
+    pass
+
+
+class Driver(common.Driver):
+    def __init__(self, host):
+        self.host = host
+
+    @classmethod
+    async def for_host(cls, host, force=False):  # type: ignore
+        return cls(host)
+
+    async def init_controller(self):
+        self.host.ready = True
+        await self.host.send_command(HCI_Reset_Command(), check_result=True)
+        await self.host.send_command(
+            Hci_Intel_DDC_Config_Write_Command(
+                params=HCI_INTEL_DDC_CONFIG_WRITE_PAYLOAD
+            )
+        )