Bluetooth: mesh: Account for scan window delaying adv events

New advertising started while scanning is already enabled
would delay the first advertisement event until the end of
the current overlapping scan window in the Zephyr native BLE
controller implementation. Hence, consider this scan window
duration when calculating the advertising stop.

Relates to: zephyrproject-rtos#6083

Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>

Author: cvinayak

subsys/bluetooth/host/mesh/adv.c

@@ -1,6 +1,7 @@
 /*  Bluetooth Mesh */
 
 /*
+ * Copyright (c) 2018 Nordic Semiconductor ASA
  * Copyright (c) 2017 Intel Corporation
  *
  * SPDX-License-Identifier: Apache-2.0
@@ -28,18 +29,20 @@
 #include "prov.h"
 #include "proxy.h"
 
-/* Window and Interval are equal for continuous scanning */
-#define MESH_SCAN_INTERVAL 0x10
-#define MESH_SCAN_WINDOW   0x10
-
 /* Convert from ms to 0.625ms units */
-#define ADV_INT(_ms) ((_ms) * 8 / 5)
+#define ADV_SCAN_UNIT(_ms) ((_ms) * 8 / 5)
+
+/* Window and Interval are equal for continuous scanning */
+#define MESH_SCAN_INTERVAL_MS 10
+#define MESH_SCAN_WINDOW_MS   10
+#define MESH_SCAN_INTERVAL    ADV_SCAN_UNIT(MESH_SCAN_INTERVAL_MS)
+#define MESH_SCAN_WINDOW      ADV_SCAN_UNIT(MESH_SCAN_WINDOW_MS)
 
 /* Pre-5.0 controllers enforce a minimum interval of 100ms
  * whereas 5.0+ controllers can go down to 20ms.
  */
-#define ADV_INT_DEFAULT  K_MSEC(100)
-#define ADV_INT_FAST     K_MSEC(20)
+#define ADV_INT_DEFAULT_MS 100
+#define ADV_INT_FAST_MS    20
 
 /* TinyCrypt PRNG consumes a lot of stack space, so we need to have
  * an increased call stack whenever it's used.
@@ -91,7 +94,7 @@ static inline void adv_send_end(int err, const struct bt_mesh_send_cb *cb,
 static inline void adv_send(struct net_buf *buf)
 {
 	const s32_t adv_int_min = ((bt_dev.hci_version >= BT_HCI_VERSION_5_0) ?
-				   ADV_INT_FAST : ADV_INT_DEFAULT);
+				   ADV_INT_FAST_MS : ADV_INT_DEFAULT_MS);
 	const struct bt_mesh_send_cb *cb = BT_MESH_ADV(buf)->cb;
 	void *cb_data = BT_MESH_ADV(buf)->cb_data;
 	struct bt_le_adv_param param;
@@ -100,7 +103,8 @@ static inline void adv_send(struct net_buf *buf)
 	int err;
 
 	adv_int = max(adv_int_min, BT_MESH_ADV(buf)->adv_int);
-	duration = (BT_MESH_ADV(buf)->count + 1) * (adv_int + 10);
+	duration = MESH_SCAN_WINDOW_MS +
+		   ((BT_MESH_ADV(buf)->count + 1) * (adv_int + 10));
 
 	BT_DBG("type %u len %u: %s", BT_MESH_ADV(buf)->type,
 	       buf->len, bt_hex(buf->data, buf->len));
@@ -112,7 +116,7 @@ static inline void adv_send(struct net_buf *buf)
 	ad.data = buf->data;
 
 	param.options = 0;
-	param.interval_min = ADV_INT(adv_int);
+	param.interval_min = ADV_SCAN_UNIT(adv_int);
 	param.interval_max = param.interval_min;
 	param.own_addr = NULL;
 
@@ -126,7 +130,7 @@ static inline void adv_send(struct net_buf *buf)
 
 	BT_DBG("Advertising started. Sleeping %u ms", duration);
 
-	k_sleep(duration);
+	k_sleep(K_MSEC(duration));
 
 	err = bt_le_adv_stop();
 	adv_send_end(err, cb, cb_data);