do this universally

selfdrive/car/chrysler/carstate.py

@@ -75,16 +75,14 @@ class CarState(CarStateBase):
     )
 
     # Buttons
-    button_events = []
     for button in BUTTONS:
       state = (cp.vl[button.can_addr][button.can_msg] in button.values)
       if self.button_states[button.event_type] != state:
         event = car.CarState.ButtonEvent.new_message()
         event.type = button.event_type
         event.pressed = state
-        button_events.append(event)
+        self.button_events.append(event)
       self.button_states[button.event_type] = state
-    self.button_events = button_events
 
     # button presses
     ret.leftBlinker, ret.rightBlinker = ret.leftBlinkerOn, ret.rightBlinkerOn = self.update_blinker_from_stalk(200, cp.vl["STEERING_LEVERS"]["TURN_SIGNALS"] == 1,

selfdrive/car/ford/carstate.py

@@ -87,16 +87,14 @@ class CarState(CarStateBase):
         ret.gearShifter = GearShifter.drive
 
     # Buttons
-    button_events = []
     for button in BUTTONS:
       state = (cp.vl[button.can_addr][button.can_msg] in button.values)
       if self.button_states[button.event_type] != state:
         event = car.CarState.ButtonEvent.new_message()
         event.type = button.event_type
         event.pressed = state
-        button_events.append(event)
+        self.button_events.append(event)
       self.button_states[button.event_type] = state
-    self.button_events = button_events
 
     # safety
     ret.stockFcw = bool(cp_cam.vl["ACCDATA_3"]["FcwVisblWarn_B_Rq"])

selfdrive/car/gm/carstate.py

@@ -33,7 +33,6 @@ class CarState(CarStateBase):
     self.prev_lkas_enabled = False
 
   def update(self, pt_cp, cam_cp, loopback_cp):
-    self.button_events = []
     ret = car.CarState.new_message()
 
     self.prev_cruise_buttons = self.cruise_buttons

selfdrive/car/honda/carstate.py

@@ -111,7 +111,6 @@ class CarState(CarStateBase):
     self.dash_speed_seen = False
 
   def update(self, cp, cp_cam, cp_body):
-    self.button_events = []
     ret = car.CarState.new_message()
 
     # car params

selfdrive/car/hyundai/carstate.py

@@ -63,7 +63,6 @@ class CarState(CarStateBase):
     self._speed_limit_clu = 0
 
   def update(self, cp, cp_cam):
-    self.button_events = []
     if self.CP.carFingerprint in CANFD_CAR:
       return self.update_canfd(cp, cp_cam)
 

selfdrive/car/interfaces.py

@@ -426,6 +426,8 @@ class CarInterfaceBase(ABC):
       if cp is not None:
         cp.update_strings(can_strings)
 
+    self.CS.button_events = []
+
     # get CarState
     ret = self._update(c)
 

selfdrive/car/mazda/carstate.py

@@ -55,16 +55,14 @@ class CarState(CarStateBase):
     ret.gearShifter = self.parse_gear_shifter(self.shifter_values.get(can_gear, None))
 
     # Buttons
-    button_events = []
     for button in BUTTONS:
       state = (cp.vl[button.can_addr][button.can_msg] in button.values)
       if self.button_states[button.event_type] != state:
         event = car.CarState.ButtonEvent.new_message()
         event.type = button.event_type
         event.pressed = state
-        button_events.append(event)
+        self.button_events.append(event)
       self.button_states[button.event_type] = state
-    self.button_events = button_events
 
     ret.genericToggle = bool(cp.vl["BLINK_INFO"]["HIGH_BEAMS"])
     ret.leftBlindspot = cp.vl["BSM"]["LEFT_BS_STATUS"] != 0

selfdrive/car/nissan/carstate.py

@@ -24,7 +24,6 @@ class CarState(CarStateBase):
     self.distance_button = 0
 
   def update(self, cp, cp_adas, cp_cam):
-    self.button_events = []
     ret = car.CarState.new_message()
 
     self.prev_distance_button = self.distance_button

selfdrive/car/subaru/carstate.py

@@ -20,7 +20,6 @@ class CarState(CarStateBase):
     self.prev_lkas_enabled = None
 
   def update(self, cp, cp_cam, cp_body):
-    self.button_events = []
     ret = car.CarState.new_message()
 
     self.prev_mads_enabled = self.mads_enabled

selfdrive/car/toyota/carstate.py

@@ -85,7 +85,6 @@ class CarState(CarStateBase):
     self.frame = 0
 
   def update(self, cp, cp_cam):
-    self.button_events = []
     ret = car.CarState.new_message()
 
     self.prev_mads_enabled = self.mads_enabled