import struct import time import typing import ha_mqtt_discoverable import ha_mqtt_discoverable.sensors import paho.mqtt.client import usb.core import usb.util class Desk: """ Controls my Linak desk, which is a CBD4P controller connected via USB2LIN06 This particular combination doesn't seem to report desk height, so it is estimated from the physical controller that does work. """ # Source of data: # https://github.com/UrbanskiDawid/usb2lin06-HID-in-linux-for-LINAK-Desk-Control-Cable # https://github.com/monofox/python-linak-desk-control # https://github.com/gryf/linak-ctrl # Desk Control Basic Software # https://www.linak-us.com/products/controls/desk-control-basic-software/ # Says it's connected but doesn't report height and buttons do nothing # Expected, as manual says it only works with CBD4A or CBD6 # Decompiled with ILSpy (easy), doesn't offer much though # CBD4+5 Configurator # https://www.linak.nl/technische-ondersteuning/#/cbd4-cbd6s-configurator # Connects, report software number and version # All setting values are suspiciously 0 though # Decompiled with Ghidra (hard), didn't go super far VEND = 0x12D3 PROD = 0x0002 # Official apps use HID library, although only managed to barely make # pyhidapi read manufacturer and product once after device reset BUF_LEN = 64 MOVE_CMD_REPEAT_INTERVAL = 0.2 # s STOP_CMD_INTERVAL = 1 # s MAX_EST_INTERVAL = 10 # s # Theoritical height values VALUE_MIN = 0x0000 VALUE_MAX = 0x7FFE VALUE_DOWN = 0x7FFF VALUE_UP = 0x8000 VALUE_STOP = 0x8001 # Measured values VALUE_BOT = 0x0001 VALUE_TOP = 0x1A50 HEIGHT_BOT = 68 HEIGHT_TOP = 135 FULL_RISE_TIME = 17.13 # s FULL_FALL_TIME = 16.64 # s # Computed values HEIGHT_OFFSET = HEIGHT_BOT # cm HEIGHT_MULT = VALUE_TOP / (HEIGHT_TOP - HEIGHT_BOT) # unit / cm # Should be 100 in theory (1 unit = 0.1 mm) FULL_TIME = (FULL_FALL_TIME + FULL_RISE_TIME) / 2 # s SPEED_MARGIN = 0.9 # Better estimate a bit slower SPEED = (VALUE_TOP - VALUE_BOT) / FULL_TIME * SPEED_MARGIN # unit / s def _cmToUnit(self, height: float) -> int: return round((height - self.HEIGHT_OFFSET) * self.HEIGHT_MULT) def _unitToCm(self, height: int) -> float: return height / self.HEIGHT_MULT + self.HEIGHT_OFFSET def _get(self, typ: int, overflow_ok: bool = False) -> bytes: # Magic numbers: get class interface, HID get report raw = self._dev.ctrl_transfer( 0xA1, 0x01, 0x300 + typ, 0, self.BUF_LEN ).tobytes() assert raw[0] == typ size = raw[1] end = 2 + size if not overflow_ok: assert end < self.BUF_LEN return raw[2:end] # Non-implemented types: # 1, 7: some kind of stream when the device isn't initialized? # size reduces the faster you poll, increases when buttons are held # 9: unknown, always report 0 def _set(self, typ: int, buf: bytes) -> None: buf = bytes([typ]) + buf # The official apps pad, not that it doesn't seem to work without buf = buf + b"\x00" * (self.BUF_LEN - len(buf)) # Magic numbers: set class interface, HID set report self._dev.ctrl_transfer(0x21, 0x09, 0x300 + typ, 0, buf) # Non-implemented types: # Some stuff < 10 def _reset_estimations(self) -> None: self.est_value: None | int = None self.est_value_bot = float(self.VALUE_BOT) self.est_value_top = float(self.VALUE_TOP) self.last_est: float = 0.0 def _initialize(self) -> None: """ Seems to take the USB2LIN06 out of "boot mode" (name according to CBD4 Controller) which it is after reset. Permits control and reading the report. """ buf = bytes([0x04, 0x00, 0xFB]) self._set(3, buf) time.sleep(0.5) def __init__(self) -> None: self._dev = usb.core.find(idVendor=Desk.VEND, idProduct=Desk.PROD) if not self._dev: raise ValueError( f"Device {Desk.VEND}:" f"{Desk.PROD:04d} " f"not found!" ) if self._dev.is_kernel_driver_active(0): self._dev.detach_kernel_driver(0) self._initialize() self._reset_estimations() self.fetch_callback: typing.Callable[["Desk"], None] | None = None def _get_report(self) -> bytes: raw = self._get(4) assert len(raw) == 0x38 return raw def _update_estimations(self) -> None: now = time.time() delta_s = now - self.last_est if delta_s > self.MAX_EST_INTERVAL: self._reset_estimations() else: delta_u = delta_s * self.SPEED if self.destination == self.VALUE_STOP: pass elif self.destination == self.VALUE_UP: self.est_value_bot += delta_u self.est_value_top += delta_u elif self.destination == self.VALUE_DOWN: self.est_value_bot -= delta_u self.est_value_top -= delta_u else: def move_closer(start_val: float) -> float: if start_val < self.destination: end_val = start_val + delta_u return min(end_val, self.destination) else: end_val = start_val - delta_u return max(end_val, self.destination) self.est_value_bot = move_closer(self.est_value_bot) self.est_value_top = move_closer(self.est_value_top) # Clamp self.est_value_bot = max(self.VALUE_BOT, self.est_value_bot) self.est_value_top = min(self.VALUE_TOP, self.est_value_top) if self.est_value_top == self.est_value_bot: self.est_value = int(self.est_value_top) self.last_est = now def fetch(self) -> None: for _ in range(3): try: raw = self._get_report() break except usb.USBError as e: print(e) pass else: raw = self._get_report() # Allegedly, from decompiling: # https://www.linak-us.com/products/controls/desk-control-basic-software/ # Never reports anything in practice self.value = struct.unpack(" None: buf = struct.pack(" None: # Clamp position = max(self.VALUE_BOT, position) position = min(self.VALUE_TOP, position) self.fetch() while self.est_value != position: self._move(position) time.sleep(self.MOVE_CMD_REPEAT_INTERVAL) self.fetch() self.stop() def move_to(self, position: float) -> None: """ If any button is held during movement, the desk will stop moving, yet this will think it's still moving, throwing off the estimates. It's not a bug, it's a safety feature. Also if you try to make it move when it's already moving, it's going to keep moving while desyncing. That one is a bug. """ # Would to stop for a while before reversing course, without being able # to read the actual height it's just too annoying to implement return self._move_to(self._cmToUnit(position)) def stop(self) -> None: self._move(self.VALUE_STOP) time.sleep(0.5) def get_height_bounds(self) -> tuple[float, float]: return ( self._unitToCm(int(self.est_value_bot)), self._unitToCm(int(self.est_value_top)), ) def get_height(self) -> float | None: if self.est_value is None: return None else: return self._unitToCm(self.est_value) if __name__ == "__main__": desk = Desk() target_height: float | None = None # Configure the required parameters for the MQTT broker mqtt_settings = ha_mqtt_discoverable.Settings.MQTT(host="192.168.7.53") device_info = ha_mqtt_discoverable.DeviceInfo( name="Desk", identifiers="device_id", manufacturer="Linak", model="CBD4P", suggested_area="Desk", ) ndigits = 1 common_opts = { "device": device_info, "icon": "mdi:desk", "unit_of_measurement": "cm", "device_class": "distance", "expire_after": 10, } # TODO Implement proper availability in hq-mqtt-discoverable height_info = ha_mqtt_discoverable.sensors.NumberInfo( name="Height ", min=desk.HEIGHT_BOT, max=desk.HEIGHT_TOP, mode="slider", step=10 ** (-ndigits), unique_id="desk_height", **common_opts, ) height_settings = ha_mqtt_discoverable.Settings( mqtt=mqtt_settings, entity=height_info ) def height_callback( client: paho.mqtt.client.Client, user_data: None, message: paho.mqtt.client.MQTTMessage, ) -> None: global target_height number = float(message.payload.decode()) print(f"HA wants to move to: {number}") target_height = number height = ha_mqtt_discoverable.sensors.Number( height_settings, height_callback ) height_max_info = ha_mqtt_discoverable.sensors.SensorInfo( name="Estimated height max", unique_id="desk_height_max", entity_category="diagnostic", **common_opts, ) height_max_settings = ha_mqtt_discoverable.Settings( mqtt=mqtt_settings, entity=height_max_info ) height_max = ha_mqtt_discoverable.sensors.Sensor(height_max_settings) height_min_info = ha_mqtt_discoverable.sensors.SensorInfo( name="Estimated height min", unique_id="desk_height_min", entity_category="diagnostic", **common_opts, ) height_min_settings = ha_mqtt_discoverable.Settings( mqtt=mqtt_settings, entity=height_min_info ) height_min = ha_mqtt_discoverable.sensors.Sensor(height_min_settings) def fetch_callback(desk: Desk) -> None: hcur = desk.get_height() hmin, hmax = desk.get_height_bounds() # If none this will set as unknown # Also readings can be a bit outside the boundaries, # so this skips verification if isinstance(hcur, float): hcur = round(hcur, ndigits=ndigits) height._update_state(hcur) height_max._update_state(round(hmax, ndigits=ndigits)) height_min._update_state(round(hmin, ndigits=ndigits)) desk.fetch_callback = fetch_callback interval = 0.2 # Need to be rective to catch while True: if target_height: print("Start moving") temp_target_height = target_height target_height = None desk.move_to(temp_target_height) print("End moving") else: time.sleep(interval) desk.fetch()