initial import

bumble/transport/vhci.py

@@ -0,0 +1,59 @@
+# Copyright 2021-2022 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 .file import open_file_transport
+
+# -----------------------------------------------------------------------------
+# Logging
+# -----------------------------------------------------------------------------
+logger = logging.getLogger(__name__)
+
+
+# -----------------------------------------------------------------------------
+async def open_vhci_transport(spec):
+    '''
+    Open a VHCI transport (only available on some platforms).
+    The parameter string is either empty (to use the default VHCI device
+    path at /dev/vhci), or the path of a VHCI device
+    '''
+
+    HCI_VENDOR_PKT = 0xff
+    HCI_BREDR = 0x00  # Controller type
+
+    # Open the VHCI device
+    transport = await open_file_transport(spec or '/dev/vhci')
+
+    # Override the source's `data_received` method so that we can
+    # filter out the vendor packet that is received just after the
+    # initial open
+    def vhci_data_received(data):
+        if len(data) > 0 and data[0] == HCI_VENDOR_PKT:
+            if len(data) == 4:
+                hci_index = data[2] << 8 | data[3]
+                logger.info(f'HCI index {hci_index}')
+        else:
+            transport.source.parser.feed_data(data)
+
+    transport.source.data_received = vhci_data_received
+
+    # Write the initial config
+    transport.sink.on_packet(bytes([HCI_VENDOR_PKT, HCI_BREDR]))
+
+    return transport
+