[BLUETOOTH]: Always send explicit hci_ll wake-up acks.

In the (rare) event of simultaneous mutual wake up requests,
do send the chip an explicit wake-up ack. This is required
for Texas Instruments's BRF6350 chip.

Signed-off-by: Ohad Ben-Cohen <ohad@bencohen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/bluetooth/hci_ll.c b/drivers/bluetooth/hci_ll.c
index 8c3e62a17b4a6f1714d91567bf20c91b569ebff2..b91d45a41b2f6b7e88716626b392a33124b789d8 100644 (file)
--- a/drivers/bluetooth/hci_ll.c
+++ b/drivers/bluetooth/hci_ll.c
@@ -204,6 +204,19 @@ static void ll_device_want_to_wakeup(struct hci_uart *hu)
        spin_lock_irqsave(&ll->hcill_lock, flags);
 
        switch (ll->hcill_state) {
+       case HCILL_ASLEEP_TO_AWAKE:
+               /*
+                * This state means that both the host and the BRF chip
+                * have simultaneously sent a wake-up-indication packet.
+                * Traditionaly, in this case, receiving a wake-up-indication
+                * was enough and an additional wake-up-ack wasn't needed.
+                * This has changed with the BRF6350, which does require an
+                * explicit wake-up-ack. Other BRF versions, which do not
+                * require an explicit ack here, do accept it, thus it is
+                * perfectly safe to always send one.
+                */
+               BT_DBG("dual wake-up-indication");
+               /* deliberate fall-through - do not add break */
        case HCILL_ASLEEP:
                /* acknowledge device wake up */
                if (send_hcill_cmd(HCILL_WAKE_UP_ACK, hu) < 0) {
@@ -211,16 +224,8 @@ static void ll_device_want_to_wakeup(struct hci_uart *hu)
                        goto out;
                }
                break;
-       case HCILL_ASLEEP_TO_AWAKE:
-               /*
-                * this state means that a wake-up-indication
-                * is already on its way to the device,
-                * and will serve as the required wake-up-ack
-                */
-               BT_DBG("dual wake-up-indication");
-               break;
        default:
-               /* any other state are illegal */
+               /* any other state is illegal */
                BT_ERR("received HCILL_WAKE_UP_IND in state %ld", ll->hcill_state);
                break;
        }