[PATCH] Bluetooth: Resume advertising after LE connection

From: Daniel Winkler
Date: Fri Nov 06 2020 - 18:20:37 EST


When an LE connection request is made, advertising is disabled and never
resumed. When a client has an active advertisement, this is disruptive.
This change adds resume logic for client-configured (non-directed)
advertisements after the connection attempt.

The patch was tested by registering an advertisement, initiating an LE
connection from a remote peer, and verifying that the advertisement is
re-activated after the connection is established. This is performed on
Hatch and Kukui Chromebooks.

Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Signed-off-by: Daniel Winkler <danielwinkler@xxxxxxxxxx>

---

net/bluetooth/hci_conn.c | 12 ++++++++++--
net/bluetooth/hci_request.c | 21 ++++++++++++++++-----
net/bluetooth/hci_request.h | 2 ++
3 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index d0c1024bf60083..4f1cd8063e720a 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -758,6 +758,9 @@ static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)

conn = hci_lookup_le_connect(hdev);

+ if (hdev->adv_instance_cnt)
+ hci_req_resume_adv_instances(hdev);
+
if (!status) {
hci_connect_le_scan_cleanup(conn);
goto done;
@@ -1067,10 +1070,11 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
* connections most controllers will refuse to connect if
* advertising is enabled, and for slave role connections we
* anyway have to disable it in order to start directed
- * advertising.
+ * advertising. Any registered advertisements will be
+ * re-enabled after the connection attempt is finished.
*/
if (hci_dev_test_flag(hdev, HCI_LE_ADV))
- __hci_req_disable_advertising(&req);
+ __hci_req_pause_adv_instances(&req);

/* If requested to connect as slave use directed advertising */
if (conn->role == HCI_ROLE_SLAVE) {
@@ -1118,6 +1122,10 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
err = hci_req_run(&req, create_le_conn_complete);
if (err) {
hci_conn_del(conn);
+
+ if (hdev->adv_instance_cnt)
+ hci_req_resume_adv_instances(hdev);
+
return ERR_PTR(err);
}

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 6f12bab4d2fa6b..fdc6eccef9d107 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1123,9 +1123,9 @@ static void cancel_adv_timeout(struct hci_dev *hdev)
}

/* This function requires the caller holds hdev->lock */
-static void hci_suspend_adv_instances(struct hci_request *req)
+void __hci_req_pause_adv_instances(struct hci_request *req)
{
- bt_dev_dbg(req->hdev, "Suspending advertising instances");
+ bt_dev_dbg(req->hdev, "Pausing advertising instances");

/* Call to disable any advertisements active on the controller.
* This will succeed even if no advertisements are configured.
@@ -1138,7 +1138,7 @@ static void hci_suspend_adv_instances(struct hci_request *req)
}

/* This function requires the caller holds hdev->lock */
-static void hci_resume_adv_instances(struct hci_request *req)
+static void __hci_req_resume_adv_instances(struct hci_request *req)
{
struct adv_info *adv;

@@ -1161,6 +1161,17 @@ static void hci_resume_adv_instances(struct hci_request *req)
}
}

+/* This function requires the caller holds hdev->lock */
+int hci_req_resume_adv_instances(struct hci_dev *hdev)
+{
+ struct hci_request req;
+
+ hci_req_init(&req, hdev);
+ __hci_req_resume_adv_instances(&req);
+
+ return hci_req_run(&req, NULL);
+}
+
static void suspend_req_complete(struct hci_dev *hdev, u8 status, u16 opcode)
{
bt_dev_dbg(hdev, "Request complete opcode=0x%x, status=0x%x", opcode,
@@ -1214,7 +1225,7 @@ void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next)

/* Pause other advertisements */
if (hdev->adv_instance_cnt)
- hci_suspend_adv_instances(&req);
+ __hci_req_pause_adv_instances(&req);

hdev->advertising_paused = true;
hdev->advertising_old_state = old_state;
@@ -1279,7 +1290,7 @@ void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next)

/* Resume other advertisements */
if (hdev->adv_instance_cnt)
- hci_resume_adv_instances(&req);
+ __hci_req_resume_adv_instances(&req);

/* Unpause discovery */
hdev->discovery_paused = false;
diff --git a/net/bluetooth/hci_request.h b/net/bluetooth/hci_request.h
index 6a12e84c66c404..39ee8a18087a28 100644
--- a/net/bluetooth/hci_request.h
+++ b/net/bluetooth/hci_request.h
@@ -71,6 +71,8 @@ void hci_req_add_le_passive_scan(struct hci_request *req);
void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next);

void hci_req_disable_address_resolution(struct hci_dev *hdev);
+void __hci_req_pause_adv_instances(struct hci_request *req);
+int hci_req_resume_adv_instances(struct hci_dev *hdev);
void hci_req_reenable_advertising(struct hci_dev *hdev);
void __hci_req_enable_advertising(struct hci_request *req);
void __hci_req_disable_advertising(struct hci_request *req);
--
2.29.2.222.g5d2a92d10f8-goog