GM fix 'Controls Failed' on resuming after cycling main cruise switch (…

…commaai#255)

* Update car.capnp

* Update interface.py

* Update controlsd.py

* Update drive_helpers.py

* Update driver_monitor.py

* Update driver_monitor.py

cereal/car.capnp

@@ -19,6 +19,7 @@ struct CarEvent @0x9b1657f34caf3ad3 {
   immediateDisable @6 :Bool;
   preEnable @7 :Bool;
   permanent @8 :Bool;
+  resetVCruise @9 :Bool;
 
   enum EventName @0xbaa8c5d505f727de {
     # TODO: copy from error list

selfdrive/car/gm/interface.py

@@ -370,11 +370,18 @@ def update(self, c, can_strings):
       # handle button presses
       for b in ret.buttonEvents:
         # do enable on both accel and decel buttons
-        if b.type in [ButtonType.accelCruise, ButtonType.decelCruise] and not b.pressed:
+        # The ECM will fault if resume triggers an enable while speed is set to 0
+        if b.type == ButtonType.accelCruise and c.hudControl.setSpeed > 0 and c.hudControl.setSpeed < 70 and not b.pressed:
+          events.append(create_event('buttonEnable', [ET.ENABLE]))
+        if b.type == ButtonType.decelCruise and not b.pressed:
           events.append(create_event('buttonEnable', [ET.ENABLE]))
         # do disable on button down
         if b.type == ButtonType.cancel and b.pressed:
           events.append(create_event('buttonCancel', [ET.USER_DISABLE]))
+        # The ECM independently tracks a ‘speed is set’ state that is reset on main off.
+        # To keep controlsd in sync with the ECM state, generate a RESET_V_CRUISE event on main cruise presses.
+        if b.type == ButtonType.altButton3 and b.pressed:
+          events.append(create_event('buttonCancel', [ET.RESET_V_CRUISE, ET.USER_DISABLE]))
 
     ret.events = events
 

selfdrive/controls/controlsd.py

@@ -165,6 +165,10 @@ def state_transition(frame, CS, CP, state, events, soft_disable_timer, v_cruise_
   # decrease the soft disable timer at every step, as it's reset on
   # entrance in SOFT_DISABLING state
   soft_disable_timer = max(0, soft_disable_timer - 1)
+
+  # Reset v_cruise_kph to 0
+  if get_events(events, [ET.RESET_V_CRUISE]):
+    v_cruise_kph = 0
 
   # DISABLED
   if state == State.disabled:

selfdrive/controls/lib/drive_helpers.py

@@ -35,6 +35,7 @@ class EventTypes:
   SOFT_DISABLE = 'softDisable'
   IMMEDIATE_DISABLE = 'immediateDisable'
   PERMANENT = 'permanent'
+  RESET_V_CRUISE = 'resetVCruise'
 
 
 def create_event(name, types):