diff --git a/selfdrive/controls/lib/longitudinal_planner.py b/selfdrive/controls/lib/longitudinal_planner.py
index 96c993eec7..eb895c3e86 100755
--- a/selfdrive/controls/lib/longitudinal_planner.py
+++ b/selfdrive/controls/lib/longitudinal_planner.py
@@ -93,14 +93,15 @@ class LongitudinalPlanner:
       j = np.zeros(len(T_IDXS_MPC))
     return x, v, a, j
 
-  def update(self, sm, buttonEvents):
+  def update(self, sm, carState_sock):
     if self.param_read_counter % 50 == 0:
       self.read_param()
 
     # decrement personality on distance button press
-    if any(not be.pressed and be.type == ButtonType.gapAdjustCruise for be in buttonEvents):
-      self.personality = (self.personality - 1) % 3
-      self.write_param()
+    for m in messaging.drain_sock(carState_sock, wait_for_one=False):
+      if any(not be.pressed and be.type == ButtonType.gapAdjustCruise for be in m.carState.buttonEvents):
+        self.personality = (self.personality - 1) % 3
+        self.write_param()
 
     self.param_read_counter += 1
     self.mpc.mode = 'blended' if sm['controlsState'].experimentalMode else 'acc'
diff --git a/selfdrive/controls/plannerd.py b/selfdrive/controls/plannerd.py
index 32660dcb02..aaba814abc 100755
--- a/selfdrive/controls/plannerd.py
+++ b/selfdrive/controls/plannerd.py
@@ -30,18 +30,14 @@ def plannerd_thread():
   pm = messaging.PubMaster(['longitudinalPlan', 'uiPlan'])
   sm = messaging.SubMaster(['carControl', 'carState', 'controlsState', 'radarState', 'modelV2'],
                            poll='modelV2', ignore_avg_freq=['radarState'])
-
-  buttonEvents = []
+  carState_sock = messaging.sub_sock('carState')
 
   while True:
     sm.update()
-    if sm.updated['carState']:
-      buttonEvents.extend(sm['carState'].buttonEvents)
     if sm.updated['modelV2']:
-      longitudinal_planner.update(sm, buttonEvents)
+      longitudinal_planner.update(sm, carState_sock)
       longitudinal_planner.publish(sm, pm)
       publish_ui_plan(sm, pm, longitudinal_planner)
-      buttonEvents.clear()
 
 def main():
   plannerd_thread()
diff --git a/selfdrive/test/longitudinal_maneuvers/plant.py b/selfdrive/test/longitudinal_maneuvers/plant.py
index 1be6e71e8b..7e9576fdec 100755
--- a/selfdrive/test/longitudinal_maneuvers/plant.py
+++ b/selfdrive/test/longitudinal_maneuvers/plant.py
@@ -50,6 +50,7 @@ class Plant:
     from openpilot.selfdrive.car.honda.interface import CarInterface
 
     self.planner = LongitudinalPlanner(CarInterface.get_non_essential_params(CAR.CIVIC), init_v=self.speed)
+    self.carState_sock = messaging.sub_sock('carState')
 
   @property
   def current_time(self):
@@ -121,7 +122,7 @@ class Plant:
           'carState': car_state.carState,
           'controlsState': control.controlsState,
           'modelV2': model.modelV2}
-    self.planner.update(sm, [])
+    self.planner.update(sm, self.carState_sock)
     self.speed = self.planner.v_desired_filter.x
     self.acceleration = self.planner.a_desired
     self.speeds = self.planner.v_desired_trajectory.tolist()