[PATCH 4.4 147/342] Bluetooth: Use continuous scanning when creating LE connections

From: Greg Kroah-Hartman
Date: Tue Mar 01 2016 - 19:52:19 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Johan Hedberg <johan.hedberg@xxxxxxxxx>

commit 2f99536a5b34d5b0f54723067d68f6cef3f0fdc6 upstream.

All LE connections are now triggered through a preceding passive scan
and waiting for a connectable advertising report. This means we've got
the best possible guarantee that the device is within range and should
be able to request the controller to perform continuous scanning. This
way we minimize the risk that we miss out on any advertising packets.

Signed-off-by: Johan Hedberg <johan.hedberg@xxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/bluetooth/hci_conn.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -722,8 +722,12 @@ static void hci_req_add_le_create_conn(s
if (hci_update_random_address(req, false, &own_addr_type))
return;

+ /* Set window to be the same value as the interval to enable
+ * continuous scanning.
+ */
cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
- cp.scan_window = cpu_to_le16(hdev->le_scan_window);
+ cp.scan_window = cp.scan_interval;
+
bacpy(&cp.peer_addr, &conn->dst);
cp.peer_addr_type = conn->dst_type;
cp.own_address_type = own_addr_type;