try spamming buttons on bus 2

selfdrive/car/gm/carcontroller.py

@@ -5,7 +5,7 @@ from common.realtime import DT_CTRL
 from opendbc.can.packer import CANPacker
 from selfdrive.car import apply_std_steer_torque_limits
 from selfdrive.car.gm import gmcan
-from selfdrive.car.gm.values import DBC, CanBus, CarControllerParams, EV_CAR
+from selfdrive.car.gm.values import DBC, CanBus, CarControllerParams, CruiseButtons, EV_CAR
 
 VisualAlert = car.CarControl.HUDControl.VisualAlert
 NetworkLocation = car.CarParams.NetworkLocation
@@ -107,6 +107,14 @@ class CarController:
       if self.CP.networkLocation == NetworkLocation.gateway and self.frame % self.params.ADAS_KEEPALIVE_STEP == 0:
         can_sends += gmcan.create_adas_keepalive(CanBus.POWERTRAIN)
 
+    elif self.CP.networkLocation == NetworkLocation.fwdCamera:
+      # Stock longitudinal, integrated at camera
+      if self.frame % 3 == 0:
+        if CC.cruiseControl.cancel:
+          can_sends.append(gmcan.create_buttons(self.packer_pt, CruiseButtons.CANCEL))
+        elif CC.cruiseControl.resume:
+          can_sends.append(gmcan.create_buttons(self.packer_pt, CruiseButtons.RES_ACCEL))
+
     # Show green icon when LKA torque is applied, and
     # alarming orange icon when approaching torque limit.
     # If not sent again, LKA icon disappears in about 5 seconds.

selfdrive/car/gm/gmcan.py

@@ -1,5 +1,10 @@
 from selfdrive.car import make_can_msg
 
+def create_buttons(packer, button):
+  values = {}  # ascm_steering_button
+  values["ACCButtons"] = button
+  return packer.make_can_msg("ASCMSteeringButton", 2, values)
+
 def create_steering_control(packer, bus, apply_steer, idx, lkas_active):
 
   values = {