don't loop

common/params.cc

@@ -255,6 +255,7 @@ std::unordered_map<std::string, uint32_t> keys = {
     {"EnforceTorqueLateral", PERSISTENT | BACKUP},
     {"EnhancedScc", PERSISTENT | BACKUP},
     {"FeatureStatus", PERSISTENT | BACKUP},
+    {"Fingerprints", CLEAR_ON_MANAGER_START | CLEAR_ON_ONROAD_TRANSITION},
     {"FleetManagerPin", PERSISTENT},
     {"ForceOffroad", CLEAR_ON_MANAGER_START},
     {"GmapKey", PERSISTENT | BACKUP},

selfdrive/car/car_helpers.py

@@ -169,6 +169,7 @@ def fingerprint(logcan, sendcan, num_pandas):
   # drain CAN socket so we get the latest messages
   messaging.drain_sock_raw(logcan)
   car_fingerprint, finger = can_fingerprint(lambda: get_one_can(logcan))
+  params.put("Fingerprints", repr(finger), len(repr(finger)))
 
   exact_match = True
   source = car.CarParams.FingerprintSource.can

selfdrive/car/hyundai/interface.py

@@ -1,7 +1,8 @@
+import ast
+
 from cereal import car
 from panda import Panda
 from openpilot.common.params import Params
-from openpilot.selfdrive.car.car_helpers import can_fingerprint, get_one_can
 from openpilot.selfdrive.car.hyundai.enable_radar_tracks import enable_radar_tracks
 from openpilot.selfdrive.car.hyundai.hyundaicanfd import CanBus
 from openpilot.selfdrive.car.hyundai.values import HyundaiFlags, HyundaiFlagsSP, CAR, DBC, CANFD_CAR, CAMERA_SCC_CAR, CANFD_RADAR_SCC_CAR, \
@@ -210,7 +211,7 @@ class CarInterface(CarInterfaceBase):
       elif rt_avail != rt_avail_cache:
         params.put_bool_nonblocking("HyundaiRadarTracksAvailableCache", rt_avail)
       else:
-        _, fingerprint = can_fingerprint(lambda: get_one_can(logcan))
+        fingerprint = ast.literal_eval(params.get("Fingerprints", encoding="utf8"))
         if RADAR_START_ADDR in fingerprint[1] and DBC[CP.carFingerprint]["radar"] is not None:
           params.put_bool_nonblocking("HyundaiRadarTracksAvailable", True)
         elif RADAR_START_ADDR not in fingerprint[1] or DBC[CP.carFingerprint]["radar"] is None: