Simon Gardling 5798caef37 forza-trigger: hysteresis on is_race_on (real fix for between-race clicks) ...

Strace post-deploy showed the daemon flipping every other packet between
in-race state (mode 0x21 FEEDBACK + LED green) and out-of-race state
(mode 0x05 OFF + LED black). 8 writes, 8 transitions in 5s — every
HID OUT report a state change.

Root cause: FH5 emits packets where the is_race_on field alternates
True/False at packet rate during menu/loading/transition states.
Cosmii's RPM_ACCUMULATOR debounce only handles the 'flag stuck True
when we're really in a menu' case (quirk #1); it does nothing for
'flag flipping at packet rate' (quirk #2).

Fix: split the read from the hysteresis. is_race_on now returns the
raw flag with quirk #1 applied. commit_in_race applies a packet-count
hysteresis (IN_RACE_HYSTERESIS_PACKETS = 30 ≈ 0.5s at 60Hz) — only
after N consecutive packets of the new value does the committed
in-race state flip. Alternation just keeps the pending counter
oscillating near 0; it never reaches threshold and the run-loop sees
a stable state.

Architecture: hysteresis in a separate function (not in is_race_on)
because the run-loop must update state.last_in_race AFTER side
effects, not before — otherwise the elif transition-detection
breaks. is_race_on stays pure read; commit_in_race is the gatekeeper;
run-loop sets state.last_in_race once at end of packet handling.

Tests grew 54→58. New TestCommitInRace covers:
  - stable input (no pending growth)
  - worst-case alternation (never commits)
  - N consecutive packets commit
  - matching raw resets pending counter

TestIsRaceOn renamed to reflect new (narrower) responsibility.

2026-05-07 15:11:35 -04:00

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