From bb425b3cfe1effe3440deaf2157d75a35f1aa1eb Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 13 Apr 2026 20:58:11 +0000
Subject: [PATCH] Fix cross-half RPI timing with SPLIT_ACTIVITY_ENABLE +
 last_input_activity_elapsed

Agent-Logs-Url: https://github.com/timfee/qmk_userspace/sessions/c129e415-070b-4b3e-b26d-2262310412aa

Co-authored-by: timfee <3246342+timfee@users.noreply.github.com>
---
 users/timfee/config.h |  1 +
 users/timfee/timfee.c | 13 ++++++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/users/timfee/config.h b/users/timfee/config.h
index 75a91967..f28ca664 100644
--- a/users/timfee/config.h
+++ b/users/timfee/config.h
@@ -29,5 +29,6 @@
 // ── Split transport ──
 #define SPLIT_TRANSPORT_MIRROR
 #define SPLIT_WPM_ENABLE
+#define SPLIT_ACTIVITY_ENABLE
 #define SPLIT_WATCHDOG_TIMEOUT 4000
 #define SPLIT_TRANSACTION_IDS_USER USER_SYNC_OLED_STATE, USER_SYNC_LASTKEY, USER_SYNC_PRESSES
diff --git a/users/timfee/timfee.c b/users/timfee/timfee.c
index c06079c2..10969ba6 100644
--- a/users/timfee/timfee.c
+++ b/users/timfee/timfee.c
@@ -6,7 +6,8 @@
 #endif
 
 // ── State for require-prior-idle ──
-static uint16_t last_key_time = 0;
+// (last_key_time removed: using last_input_activity_elapsed() instead, which
+//  is synced from both halves via SPLIT_ACTIVITY_ENABLE, fixing cross-half RPI)
 
 // ── Combos (matching Vial config) ──
 const uint16_t PROGMEM lparen_combo[] = {KC_R, KC_T, COMBO_END};
@@ -213,8 +214,12 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
         }
 #endif
 
-        // Require-prior-idle handling
-        uint16_t elapsed = timer_elapsed(last_key_time);
+        // Require-prior-idle: force tap if pressed too soon after any recent
+        // activity on either half. SPLIT_ACTIVITY_ENABLE synchronizes the
+        // underlying activity timestamp from the slave to the master at the
+        // transport level, so last_input_activity_elapsed() reflects the most
+        // recent keypress on either half — not just the master side.
+        uint32_t elapsed = last_input_activity_elapsed();
 
         switch (keycode) {
             case GU_SPC:
@@ -266,8 +271,6 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
                 }
                 break;
         }
-
-        last_key_time = timer_read();
     }
     return true;
 }