Support LE Subrating

bumble/controller.py

@@ -1259,6 +1259,56 @@ class Controller:
         )
         return bytes([HCI_SUCCESS]) + bd_addr
 
+    def on_hci_le_set_default_subrate_command(
+        self, command: hci.HCI_LE_Set_Default_Subrate_Command
+    ):
+        '''
+        See Bluetooth spec Vol 6, Part E - 7.8.123 LE Set Event Mask Command
+        '''
+
+        if (
+            command.subrate_max * (command.max_latency) > 500
+            or command.subrate_max < command.subrate_min
+            or command.continuation_number >= command.subrate_max
+        ):
+            return bytes([HCI_INVALID_HCI_COMMAND_PARAMETERS_ERROR])
+
+        return bytes([HCI_SUCCESS])
+
+    def on_hci_le_subrate_request_command(
+        self, command: hci.HCI_LE_Subrate_Request_Command
+    ):
+        '''
+        See Bluetooth spec Vol 6, Part E - 7.8.124 LE Subrate Request command
+        '''
+        if (
+            command.subrate_max * (command.max_latency) > 500
+            or command.continuation_number < command.continuation_number
+            or command.subrate_max < command.subrate_min
+            or command.continuation_number >= command.subrate_max
+        ):
+            return bytes([HCI_INVALID_HCI_COMMAND_PARAMETERS_ERROR])
+
+        self.send_hci_packet(
+            hci.HCI_Command_Status_Event(
+                status=hci.HCI_SUCCESS,
+                num_hci_command_packets=1,
+                command_opcode=command.op_code,
+            )
+        )
+
+        self.send_hci_packet(
+            hci.HCI_LE_Subrate_Change_Event(
+                status=hci.HCI_SUCCESS,
+                connection_handle=command.connection_handle,
+                subrate_factor=2,
+                peripheral_latency=2,
+                continuation_number=command.continuation_number,
+                supervision_timeout=command.supervision_timeout,
+            )
+        )
+        return None
+
     def on_hci_le_set_event_mask_command(self, command):
         '''
         See Bluetooth spec Vol 4, Part E - 7.8.1 LE Set Event Mask Command

bumble/device.py

@@ -1752,6 +1752,8 @@ class Connection(utils.CompositeEventEmitter):
     EVENT_CIS_REQUEST = "cis_request"
     EVENT_CIS_ESTABLISHMENT = "cis_establishment"
     EVENT_CIS_ESTABLISHMENT_FAILURE = "cis_establishment_failure"
+    EVENT_LE_SUBRATE_CHANGE = "le_subrate_change"
+    EVENT_LE_SUBRATE_CHANGE_FAILURE = "le_subrate_change_failure"
 
     @utils.composite_listener
     class Listener:
@@ -1787,6 +1789,8 @@ class Connection(utils.CompositeEventEmitter):
         connection_interval: float  # Connection interval, in milliseconds. [LE only]
         peripheral_latency: int  # Peripheral latency, in number of intervals. [LE only]
         supervision_timeout: float  # Supervision timeout, in milliseconds.
+        subrate_factor: int = 1
+        continuation_number: int = 0
 
     def __init__(
         self,
@@ -2058,6 +2062,7 @@ class DeviceConfiguration:
     le_simultaneous_enabled: bool = False
     le_privacy_enabled: bool = False
     le_rpa_timeout: int = DEVICE_DEFAULT_LE_RPA_TIMEOUT
+    le_subrate_enabled: bool = True
     classic_enabled: bool = False
     classic_sc_enabled: bool = True
     classic_ssp_enabled: bool = True
@@ -2410,6 +2415,7 @@ class Device(utils.CompositeEventEmitter):
         self.le_privacy_enabled = config.le_privacy_enabled
         self.le_rpa_timeout = config.le_rpa_timeout
         self.le_rpa_periodic_update_task: Optional[asyncio.Task] = None
+        self.le_subrate_enabled = config.le_subrate_enabled
         self.classic_enabled = config.classic_enabled
         self.cis_enabled = config.cis_enabled
         self.classic_sc_enabled = config.classic_sc_enabled
@@ -6226,6 +6232,22 @@ class Device(utils.CompositeEventEmitter):
         )
         connection.emit(connection.EVENT_CONNECTION_PHY_UPDATE_FAILURE, error)
 
+    @host_event_handler
+    @with_connection_from_handle
+    def on_le_subrate_change(
+        self,
+        connection: Connection,
+        subrate_factor: int,
+        peripheral_latency: int,
+        continuation_number: int,
+        supervision_timeout: int,
+    ):
+        connection.parameters.subrate_factor = subrate_factor
+        connection.parameters.peripheral_latency = peripheral_latency
+        connection.parameters.continuation_number = continuation_number
+        connection.parameters.supervision_timeout = supervision_timeout * 10
+        connection.emit(connection.EVENT_LE_SUBRATE_CHANGE)
+
     @host_event_handler
     @with_connection_from_handle
     def on_connection_att_mtu_update(self, connection, att_mtu):

bumble/hci.py

@@ -5315,6 +5315,37 @@ class HCI_LE_Set_Host_Feature_Command(HCI_Command):
     bit_value: int = field(metadata=metadata(1))
 
 
+# -----------------------------------------------------------------------------
+@HCI_Command.command
+@dataclasses.dataclass
+class HCI_LE_Set_Default_Subrate_Command(HCI_Command):
+    '''
+    See Bluetooth spec @ 7.8.123 LE Set Default Subrate command
+    '''
+
+    subrate_min: int = field(metadata=metadata(2))
+    subrate_max: int = field(metadata=metadata(2))
+    max_latency: int = field(metadata=metadata(2))
+    continuation_number: int = field(metadata=metadata(2))
+    supervision_timeout: int = field(metadata=metadata(2))
+
+
+# -----------------------------------------------------------------------------
+@HCI_Command.command
+@dataclasses.dataclass
+class HCI_LE_Subrate_Request_Command(HCI_Command):
+    '''
+    See Bluetooth spec @ 7.8.124 LE Subrate Request command
+    '''
+
+    connection_handle: int = field(metadata=metadata(2))
+    subrate_min: int = field(metadata=metadata(2))
+    subrate_max: int = field(metadata=metadata(2))
+    max_latency: int = field(metadata=metadata(2))
+    continuation_number: int = field(metadata=metadata(2))
+    supervision_timeout: int = field(metadata=metadata(2))
+
+
 # -----------------------------------------------------------------------------
 @HCI_Command.command
 @dataclasses.dataclass
@@ -6460,6 +6491,22 @@ class HCI_LE_BIGInfo_Advertising_Report_Event(HCI_LE_Meta_Event):
     encryption: int = field(metadata=metadata(1))
 
 
+# -----------------------------------------------------------------------------
+@HCI_LE_Meta_Event.event
+@dataclasses.dataclass
+class HCI_LE_Subrate_Change_Event(HCI_LE_Meta_Event):
+    '''
+    See Bluetooth spec @ 7.7.65.35 LE Subrate Change event
+    '''
+
+    status: int = field(metadata=metadata(1))
+    connection_handle: int = field(metadata=metadata(2))
+    subrate_factor: int = field(metadata=metadata(2))
+    peripheral_latency: int = field(metadata=metadata(2))
+    continuation_number: int = field(metadata=metadata(2))
+    supervision_timeout: int = field(metadata=metadata(2))
+
+
 # -----------------------------------------------------------------------------
 @HCI_LE_Meta_Event.event
 @dataclasses.dataclass

bumble/host.py

@@ -1645,5 +1645,15 @@ class Host(utils.EventEmitter):
     def on_hci_le_cs_subevent_result_continue_event(self, event):
         self.emit('cs_subevent_result_continue', event)
 
+    def on_hci_le_subrate_change_event(self, event: hci.HCI_LE_Subrate_Change_Event):
+        self.emit(
+            'le_subrate_change',
+            event.connection_handle,
+            event.subrate_factor,
+            event.peripheral_latency,
+            event.continuation_number,
+            event.supervision_timeout,
+        )
+
     def on_hci_vendor_event(self, event):
         self.emit('vendor_event', event)

tests/device_test.py

@@ -611,6 +611,37 @@ async def test_enter_and_exit_sniff_mode():
     assert devices.connections[0].classic_interval == 2
 
 
+# -----------------------------------------------------------------------------
+@pytest.mark.asyncio
+async def test_le_request_subrate():
+    devices = TwoDevices()
+    await devices.setup_connection()
+
+    q = asyncio.Queue()
+
+    def on_le_subrate_change():
+        q.put_nowait(lambda: None)
+
+    devices.connections[0].on(Connection.EVENT_LE_SUBRATE_CHANGE, on_le_subrate_change)
+
+    await devices[0].send_command(
+        hci.HCI_LE_Subrate_Request_Command(
+            connection_handle=devices.connections[0].handle,
+            subrate_min=2,
+            subrate_max=2,
+            max_latency=2,
+            continuation_number=1,
+            supervision_timeout=2,
+        )
+    )
+
+    await asyncio.wait_for(q.get(), _TIMEOUT)
+    assert devices.connections[0].parameters.subrate_factor == 2
+    assert devices.connections[0].parameters.peripheral_latency == 2
+    assert devices.connections[0].parameters.continuation_number == 1
+    assert devices.connections[0].parameters.supervision_timeout == 20
+
+
 # -----------------------------------------------------------------------------
 @pytest.mark.asyncio
 async def test_power_on_default_static_address_should_not_be_any():