From: Anderson Lizardo Date: Wed, 27 Jul 2011 21:40:09 +0000 (-0300) Subject: Bluetooth: use recommended LE connection parameters X-Git-Tag: next-20110802~28^2~3 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=829fd5994d1372d7581e70cc5171d6eccd86884b;p=karo-tx-linux.git Bluetooth: use recommended LE connection parameters The new connection parameters now match the recommended values for Proximity and Health Thermometer profiles. The previous values were ramdomly chosen, and are either too low or too high for most cases. New values: Scan Interval: 60 ms Scan Window: 30 ms Minimum Connection Interval: 50 ms Maximum Connection Interval: 70 ms Supervision Timeout: 420 ms See "Table 5.2: Recommended Scan Interval and Scan Window Values" and "Table 5.3: Recommended Connection Interval Values" for both profiles for details. Note that the "fast connection" parameters were chosen, because we do not support yet dynamically changing these parameters from initiator side. Additionally, the Proximity profile recommends (section "4.4 Alert on Link Loss"): "It is recommended that the Link Supervision Timeout (LSTO) is set to 6x the connection interval." Minimum_CE_Length and Maximum_CE_Length were also changed from 0x0001 to 0x0000 because they are informational and optional, and old value was not reflecting reality. Signed-off-by: Anderson Lizardo Signed-off-by: Gustavo F. Padovan --- diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index ea7f031f3b04..fa6820e86578 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -56,15 +56,15 @@ static void hci_le_connect(struct hci_conn *conn) conn->sec_level = BT_SECURITY_LOW; memset(&cp, 0, sizeof(cp)); - cp.scan_interval = cpu_to_le16(0x0004); - cp.scan_window = cpu_to_le16(0x0004); + cp.scan_interval = cpu_to_le16(0x0060); + cp.scan_window = cpu_to_le16(0x0030); bacpy(&cp.peer_addr, &conn->dst); cp.peer_addr_type = conn->dst_type; - cp.conn_interval_min = cpu_to_le16(0x0008); - cp.conn_interval_max = cpu_to_le16(0x0100); - cp.supervision_timeout = cpu_to_le16(0x0064); - cp.min_ce_len = cpu_to_le16(0x0001); - cp.max_ce_len = cpu_to_le16(0x0001); + cp.conn_interval_min = cpu_to_le16(0x0028); + cp.conn_interval_max = cpu_to_le16(0x0038); + cp.supervision_timeout = cpu_to_le16(0x002a); + cp.min_ce_len = cpu_to_le16(0x0000); + cp.max_ce_len = cpu_to_le16(0x0000); hci_send_cmd(hdev, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp); }