From fc94d4c1582bc48f8626e387abe9120b2931a8fe Mon Sep 17 00:00:00 2001
From: Xudong Zheng <7pkvm5aw@slicealias.com>
Date: Fri, 19 May 2023 18:41:08 -0400
Subject: [PATCH] refactor(split): allow central to define connection
 parameters

Fixes #1614
---
 app/src/split/bluetooth/Kconfig   | 17 +++++++++++++++--
 app/src/split/bluetooth/central.c |  4 +++-
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/app/src/split/bluetooth/Kconfig b/app/src/split/bluetooth/Kconfig
index e2c8d5c3395..0610b667a26 100644
--- a/app/src/split/bluetooth/Kconfig
+++ b/app/src/split/bluetooth/Kconfig
@@ -33,6 +33,18 @@ config ZMK_SPLIT_BLE_CENTRAL_SPLIT_RUN_QUEUE_SIZE
     int "Max number of behavior run events to queue to send to the peripheral(s)"
     default 5
 
+config ZMK_SPLIT_BLE_PREF_INT
+    int "Connection interval to use for split central/peripheral connection"
+    default 6
+
+config ZMK_SPLIT_BLE_PREF_LATENCY
+    int "Latency to use for split central/peripheral connection"
+    default 30
+
+config ZMK_SPLIT_BLE_PREF_TIMEOUT
+    int "Supervision timeout to use for split central/peripheral connection"
+    default 400
+
 endif # ZMK_SPLIT_ROLE_CENTRAL
 
 if !ZMK_SPLIT_ROLE_CENTRAL
@@ -58,8 +70,9 @@ config BT_MAX_PAIRED
 config BT_MAX_CONN
     default 1
 
-config BT_PERIPHERAL_PREF_MAX_INT
-    default 6
+# Allow central to specify connection parameters.
+config BT_GAP_AUTO_UPDATE_CONN_PARAMS
+    default n
 
 #!ZMK_SPLIT_ROLE_CENTRAL
 endif
diff --git a/app/src/split/bluetooth/central.c b/app/src/split/bluetooth/central.c
index 53e61be621a..147760ffae7 100644
--- a/app/src/split/bluetooth/central.c
+++ b/app/src/split/bluetooth/central.c
@@ -383,7 +383,9 @@ static bool split_central_eir_found(const bt_addr_le_t *addr) {
     struct peripheral_slot *slot = &peripherals[slot_idx];
 
     LOG_DBG("Initiating new connnection");
-    struct bt_le_conn_param *param = BT_LE_CONN_PARAM(0x0006, 0x0006, 30, 400);
+    struct bt_le_conn_param *param =
+        BT_LE_CONN_PARAM(CONFIG_ZMK_SPLIT_BLE_PREF_INT, CONFIG_ZMK_SPLIT_BLE_PREF_INT,
+                         CONFIG_ZMK_SPLIT_BLE_PREF_LATENCY, CONFIG_ZMK_SPLIT_BLE_PREF_TIMEOUT);
     err = bt_conn_le_create(addr, BT_CONN_LE_CREATE_CONN, param, &slot->conn);
     if (err < 0) {
         LOG_ERR("Create conn failed (err %d) (create conn? 0x%04x)", err, BT_HCI_OP_LE_CREATE_CONN);