Bluetooth: Enter active mode before establishing a SCO link.

When in sniff mode with a long interval time (1.28s) it can take 4+ seconds to
establish a SCO link. Fix by requesting active mode before requesting SCO
connection. This improves SCO setup time to ~500ms.

Bluetooth headsets that use a long interval time, and exhibit the long SCO
connection time include Motorola H790, HX1 and H17. They have a CSR 2.1 chipset

Verified this behavior and fix with host Bluetooth chipsets: BCM4329 and
TI1271.

Signed-off-by: Nick Pelly <npelly@google.com>

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index b7c4224f4e7dee01288dd31f4581f7a8821c7a21..b10e3cdb08f87358ca64d0db8cf83c27f5ad624a 100644 (file)
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -377,6 +377,9 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
 
        if (acl->state == BT_CONNECTED &&
                        (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
+               acl->power_save = 1;
+               hci_conn_enter_active_mode(acl);
+
                if (lmp_esco_capable(hdev))
                        hci_setup_sync(sco, acl->handle);
                else