From: Ohad Ben-Cohen <ohad@bencohen.org>
Date: Fri, 11 Jan 2008 06:24:43 +0000 (-0800)
Subject: [BLUETOOTH]: Always send explicit hci_ll wake-up acks.
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=5c5482266537fdb24d6b8462540d8f65a6007a97;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git

[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 8c3e62a17b4..b91d45a41b2 100644
--- 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;
 	}