From b9cdc6a9b721c1a598ad9bf1da7fbbd9d2ab0f9f Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@proton.me>
Date: Thu, 7 May 2026 15:00:59 -0400
Subject: [PATCH] forza-trigger: stop per-packet writes between races (fix
 periodic clicks)
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User reports periodic clicks and LED color changes on the controller
"between races". Theory: out-of-race, the run loop was calling
reset_triggers(controller) AND apply_lightbar(controller, ...) on
every Forza packet (60Hz). Even though both call sites land in
library code that nominally dedupes "same state" writes, in practice
any state change anywhere — including the lightbar dropping a green
channel value as RPM coasts down to idle — triggers a full HID OUT
report rewrite. The OUT report carries the trigger configuration too;
the controller firmware reacts on receipt and produces an audible
click each time.

Fix: out-of-race path becomes edge-triggered. On the in-race → menu
transition we run state.reset() + reset_all() once (turning both
triggers off and the lightbar to (0,0,0)). Subsequent menu packets
make no controller calls at all until in_race flips back to True.
First in-race packet then re-engages handlers and the RPM-driven
lightbar.

Side effect: the menu-mode car-class lightbar coloring is gone — the
bar stays black between races. If we want it back later, it should
be one-shot on the menu transition (NOT updated per-packet). For now
keep it simple: in-race only.

Build clean; tests unchanged (54/54 still pass — they exercise
handlers directly, not the run loop).
---
 hosts/yarn/forza-trigger/forza_trigger.py | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/hosts/yarn/forza-trigger/forza_trigger.py b/hosts/yarn/forza-trigger/forza_trigger.py
index f20bfd6..ddea9db 100644
--- a/hosts/yarn/forza-trigger/forza_trigger.py
+++ b/hosts/yarn/forza-trigger/forza_trigger.py
@@ -777,17 +777,18 @@ def run(host: str, port: int, exit_on_idle: bool = False) -> int:
             if in_race:
                 handle_throttle(controller, pkt, state)
                 handle_brake(controller, pkt, state)
-            else:
-                # On the in-race → menu transition, partial-reset state so
-                # the next race resumption gets clean EWMA cells, fresh slip
-                # flags (so the cold-start fix at handle_throttle/brake
-                # re-fires), and a redrawn lightbar. Edge-only — repeated
-                # menu packets shouldn't keep clearing state.
-                if state.last_in_race:
-                    state.reset()
-                reset_triggers(controller)
+                apply_lightbar(controller, pkt, state, in_race=True)
+            elif state.last_in_race:
+                # in-race → menu edge: one-shot reset of state, triggers,
+                # and lightbar. We do NOT touch the controller again until
+                # the next in-race packet. Doing per-packet writes between
+                # races causes audible clicks on the trigger actuator —
+                # every HID OUT report (even the ones that look idempotent
+                # via library dedup) re-encodes the trigger config and the
+                # firmware reacts on receipt.
+                state.reset()
+                reset_all(controller)
             state.last_in_race = in_race
-            apply_lightbar(controller, pkt, state, in_race)
     finally:
         try:
             reset_all(controller)