GM: remove redundant CarController class variable (#27280)

* clean up

* fix check

* only set ts_nanos on update
old-commit-hash: 14d44e444418e1b6bd23afe5a371db886e8273e2

selfdrive/car/gm/carcontroller.py

@@ -30,7 +30,6 @@ class CarController:
     self.cancel_counter = 0
 
     self.lka_steering_cmd_counter = 0
-    self.sent_lka_steering_cmd = False
     self.lka_icon_status_last = (False, False)
 
     self.params = CarControllerParams(self.CP)
@@ -59,19 +58,17 @@ class CarController:
       # - until we're in sync with camera so counters align when relay closes, preventing a fault.
       #   openpilot can subtly drift, so this is activated throughout a drive to stay synced
       out_of_sync = self.lka_steering_cmd_counter % 4 != (CS.cam_lka_steering_cmd_counter + 1) % 4
-      if not self.sent_lka_steering_cmd or out_of_sync:
+      if CS.loopback_lka_steering_cmd_ts_nanos == 0 or out_of_sync:
         steer_step = self.params.STEER_STEP
 
-    if CS.loopback_lka_steering_cmd_updated:
-      self.lka_steering_cmd_counter += 1
-      self.sent_lka_steering_cmd = True
+    self.lka_steering_cmd_counter += 1 if CS.loopback_lka_steering_cmd_updated else 0
 
     # Avoid GM EPS faults when transmitting messages too close together: skip this transmit if we
     # received the ASCMLKASteeringCmd loopback confirmation too recently
     last_lka_steer_msg_ms = (now_nanos - CS.loopback_lka_steering_cmd_ts_nanos) * 1e-6
     if (self.frame - self.last_steer_frame) >= steer_step and last_lka_steer_msg_ms > MIN_STEER_MSG_INTERVAL_MS:
       # Initialize ASCMLKASteeringCmd counter using the camera until we get a msg on the bus
-      if not self.sent_lka_steering_cmd:
+      if CS.loopback_lka_steering_cmd_ts_nanos == 0:
         self.lka_steering_cmd_counter = CS.pt_lka_steering_cmd_counter + 1
 
       if CC.latActive:

selfdrive/car/gm/carstate.py

@@ -37,7 +37,8 @@ class CarState(CarStateBase):
 
     # Variables used for avoiding LKAS faults
     self.loopback_lka_steering_cmd_updated = len(loopback_cp.vl_all["ASCMLKASteeringCmd"]["RollingCounter"]) > 0
-    self.loopback_lka_steering_cmd_ts_nanos = loopback_cp.ts_nanos["ASCMLKASteeringCmd"]["RollingCounter"]
+    if self.loopback_lka_steering_cmd_updated:
+      self.loopback_lka_steering_cmd_ts_nanos = loopback_cp.ts_nanos["ASCMLKASteeringCmd"]["RollingCounter"]
     if self.CP.networkLocation == NetworkLocation.fwdCamera:
       self.pt_lka_steering_cmd_counter = pt_cp.vl["ASCMLKASteeringCmd"]["RollingCounter"]
       self.cam_lka_steering_cmd_counter = cam_cp.vl["ASCMLKASteeringCmd"]["RollingCounter"]