From 58b5243729395929ada4a7c8a0e520214f7bb20f Mon Sep 17 00:00:00 2001
From: jhchun <jh.chun@medithings.co.kr>
Date: Wed, 15 Jul 2026 16:01:49 +0900
Subject: [PATCH] =?UTF-8?q?BLE=20=EC=97=B0=EA=B2=B0=20=ED=8C=8C=EB=9D=BC?=
 =?UTF-8?q?=EB=AF=B8=ED=84=B0=EA=B0=80=20=EC=9D=B4=EB=AF=B8=20=EB=AA=A9?=
 =?UTF-8?q?=ED=91=9C=EA=B0=92=EC=9D=B8=20=EA=B2=BD=EC=9A=B0=20=EC=9E=AC?=
 =?UTF-8?q?=EC=9A=94=EC=B2=AD=20=EC=83=9D=EB=9E=B5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 요청 전 bt_conn_get_info()로 현재 체결값 조회
- Connection Interval, Supervision Timeout, Slave latency
---
 src/ble/ble_service.c | 41 ++++++++++++++++++++++++++++++++++++-----
 1 file changed, 36 insertions(+), 5 deletions(-)

diff --git a/src/ble/ble_service.c b/src/ble/ble_service.c
index af66d97..d40bcb8 100644
--- a/src/ble/ble_service.c
+++ b/src/ble/ble_service.c
@@ -432,6 +432,7 @@ static int ble_request_preferred_conn_params(bool count_attempt)
         .latency = BLE_SLAVE_LATENCY,
         .timeout = BLE_CONN_SUP_TIMEOUT,
     };
+    struct bt_conn_info info;
     int err;
 
     if (current_conn == NULL)
@@ -439,15 +440,41 @@ static int ble_request_preferred_conn_params(bool count_attempt)
         return -ENOTCONN;
     }
 
+    // 현재 체결된 파라미터를 조회해서, 이미 목표값이면 재요청/재시도 불필요
+    err = bt_conn_get_info(current_conn, &info);
+    if ((err == 0) && (info.type == BT_CONN_TYPE_LE))
+    {
+        uint16_t cur_interval = info.le.interval;
+        uint16_t cur_latency = info.le.latency;
+        uint16_t cur_timeout = info.le.timeout;
+
+        DBG_PRINTF("[BLE] Current params: interval=%u(%u.%01ums) latency=%u timeout=%u(%ums)\r\n",
+                   cur_interval,
+                   (cur_interval * 125U) / 100U,
+                   ((cur_interval * 125U) % 100U) / 10U,
+                   cur_latency,
+                   cur_timeout,
+                   cur_timeout * 10U);
+
+        if (ble_conn_param_is_preferred(cur_interval, cur_latency, cur_timeout))
+        {
+            DBG_PRINTF("[BLE] Already at preferred params, skip request\r\n");
+            return -EALREADY;
+        }
+    }
+
     if (count_attempt)
     {
         conn_param_update_attempts++;
     }
 
-    DBG_PRINTF("[BLE] Request params: interval=%u latency=%u timeout=%u attempt=%u\r\n",
+    DBG_PRINTF("[BLE] Request params: interval=%u(%u.%01ums) latency=%u timeout=%u(%ums) attempt=%u\r\n",
                BLE_MIN_CONN_INTERVAL,
+               (BLE_MIN_CONN_INTERVAL * 125U) / 100U,
+               ((BLE_MIN_CONN_INTERVAL * 125U) % 100U) / 10U,
                BLE_SLAVE_LATENCY,
                BLE_CONN_SUP_TIMEOUT,
+               BLE_CONN_SUP_TIMEOUT * 10U,
                conn_param_update_attempts);
 
     err = bt_conn_le_param_update(current_conn, &conn_param);
@@ -585,13 +612,17 @@ static bool le_param_req(struct bt_conn *conn, struct bt_le_conn_param *param)
     return true;
 }
 
-static void le_param_updated(struct bt_conn *conn, uint16_t interval,
-                             uint16_t latency, uint16_t timeout)
+static void le_param_updated(struct bt_conn *conn, uint16_t interval, uint16_t latency, uint16_t timeout)
 {
     ARG_UNUSED(conn);
 
-    DBG_PRINTF("[BLE] Params: interval=%d latency=%d timeout=%d\r\n",
-               interval, latency, timeout);
+    DBG_PRINTF("[BLE] Params: interval=%u(%u.%01ums) latency=%u timeout=%u(%ums)\r\n",
+               interval,
+               (interval * 125U) / 100U,
+               ((interval * 125U) % 100U) / 10U,
+               latency,
+               timeout,
+               timeout * 10U);
 
     if (ble_conn_param_is_preferred(interval, latency, timeout))
     {