VW MQB: Restore lead car indicator in instrument cluster (#26651)

* VW MQB: Lead car indicator in ACC HUD

* typo

* do this cleanup in another PR
old-commit-hash: 3cc439ce98

selfdrive/car/volkswagen/carcontroller.py

@@ -2,6 +2,7 @@ from cereal import car
 from opendbc.can.packer import CANPacker
 from common.numpy_fast import clip
 from common.conversions import Conversions as CV
+from common.realtime import DT_CTRL
 from selfdrive.car import apply_std_steer_torque_limits
 from selfdrive.car.volkswagen import mqbcan, pqcan
 from selfdrive.car.volkswagen.values import CANBUS, PQ_CARS, CarControllerParams
@@ -88,10 +89,13 @@ class CarController:
                                                        CS.out.steeringPressed, hud_alert, hud_control))
 
     if self.frame % self.CCP.ACC_HUD_STEP == 0 and self.CP.openpilotLongitudinalControl:
+      lead_distance = 0
+      if hud_control.leadVisible and self.frame * DT_CTRL > 1.0:  # Don't display lead until we know the scaling factor
+        lead_distance = 512 if CS.upscale_lead_car_signal else 8
       acc_hud_status = self.CCS.acc_hud_status_value(CS.out.cruiseState.available, CS.out.accFaulted, CC.longActive)
       set_speed = hud_control.setSpeed * CV.MS_TO_KPH  # FIXME: follow the recent displayed-speed updates, also use mph_kmh toggle to fix display rounding problem?
       can_sends.append(self.CCS.create_acc_hud_control(self.packer_pt, CANBUS.pt, acc_hud_status, set_speed,
-                                                       hud_control.leadVisible))
+                                                       lead_distance))
 
     # **** Stock ACC Button Controls **************************************** #
 

selfdrive/car/volkswagen/carstate.py

@@ -13,6 +13,7 @@ class CarState(CarStateBase):
     self.CCP = CarControllerParams(CP)
     self.button_states = {button.event_type: False for button in self.CCP.BUTTONS}
     self.esp_hold_confirmation = False
+    self.upscale_lead_car_signal = False
 
   def create_button_events(self, pt_cp, buttons):
     button_events = []
@@ -141,6 +142,9 @@ class CarState(CarStateBase):
     # Additional safety checks performed in CarInterface.
     ret.espDisabled = pt_cp.vl["ESP_21"]["ESP_Tastung_passiv"] != 0
 
+    # Digital instrument clusters expect the ACC HUD lead car distance to be scaled differently
+    self.upscale_lead_car_signal = bool(pt_cp.vl["Kombi_03"]["KBI_Variante"])
+
     return ret
 
   def update_pq(self, pt_cp, cam_cp, ext_cp, trans_type):
@@ -281,6 +285,7 @@ class CarState(CarStateBase):
       ("ESP_Tastung_passiv", "ESP_21"),          # Stability control disabled
       ("ESP_Haltebestaetigung", "ESP_21"),       # ESP hold confirmation
       ("KBI_Handbremse", "Kombi_01"),            # Manual handbrake applied
+      ("KBI_Variante", "Kombi_03"),              # Digital/full-screen instrument cluster installed
       ("TSK_Status", "TSK_06"),                  # ACC engagement status from drivetrain coordinator
       ("GRA_Hauptschalter", "GRA_ACC_01"),       # ACC button, on/off
       ("GRA_Abbrechen", "GRA_ACC_01"),           # ACC button, cancel
@@ -312,6 +317,7 @@ class CarState(CarStateBase):
       ("Airbag_02", 5),     # From J234 Airbag control module
       ("Kombi_01", 2),      # From J285 Instrument cluster
       ("Blinkmodi_02", 1),  # From J519 BCM (sent at 1Hz when no lights active, 50Hz when active)
+      ("Kombi_03", 0),      # From J285 instrument cluster (not present on older cars, 1Hz when present)
     ]
 
     if CP.transmissionType == TransmissionType.automatic:

selfdrive/car/volkswagen/mqbcan.py

@@ -96,13 +96,13 @@ def create_acc_accel_control(packer, bus, acc_type, enabled, accel, acc_control,
   return commands
 
 
-def create_acc_hud_control(packer, bus, acc_hud_status, set_speed, lead_visible):
+def create_acc_hud_control(packer, bus, acc_hud_status, set_speed, lead_distance):
   values = {
     "ACC_Status_Anzeige": acc_hud_status,
     "ACC_Wunschgeschw_02": set_speed if set_speed < 250 else 327.36,
     "ACC_Gesetzte_Zeitluecke": 3,
     "ACC_Display_Prio": 3,
-    # TODO: ACC_Abstandsindex for lead car distance, must determine analog vs digital cluster for scaling
+    "ACC_Abstandsindex": lead_distance,
   }
 
   return packer.make_can_msg("ACC_02", bus, values)

selfdrive/car/volkswagen/pqcan.py

@@ -77,12 +77,12 @@ def create_acc_accel_control(packer, bus, acc_type, enabled, accel, acc_control,
   return commands
 
 
-def create_acc_hud_control(packer, bus, acc_hud_status, set_speed, lead_visible):
+def create_acc_hud_control(packer, bus, acc_hud_status, set_speed, lead_distance):
   values = {
     "ACA_StaACC": acc_hud_status,
     "ACA_Zeitluecke": 2,
     "ACA_V_Wunsch": set_speed,
-    "ACA_gemZeitl": 8 if lead_visible else 0,
+    "ACA_gemZeitl": lead_distance,
     # TODO: ACA_ID_StaACC, ACA_AnzDisplay, ACA_kmh_mph, ACA_PrioDisp, ACA_Aend_Zeitluecke
     # display/display-prio handling probably needed to stop confusing the instrument cluster
     # kmh_mph handling probably needed to resolve rounding errors in displayed setpoint