From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Thu, 11 Aug 2022 14:20:46 -0700
Subject: Bluetooth: hci_sync: Fix suspend performance regression
Patch-mainline: v6.0-rc4
Git-commit: 1fd02d56dae35b08e4cba8e6bd2c2e7ccff68ecc
References: jsc#PED-1407

This attempts to fix suspend performance when there is no connections by
not updating the event mask.

Fixes: ef61b6ea1544 ("Bluetooth: Always set event mask on suspend")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 net/bluetooth/hci_sync.c |   24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -4964,17 +4964,21 @@ int hci_suspend_sync(struct hci_dev *hde
 	/* Prevent disconnects from causing scanning to be re-enabled */
 	hci_pause_scan_sync(hdev);
 
-	/* Soft disconnect everything (power off) */
-	err = hci_disconnect_all_sync(hdev, HCI_ERROR_REMOTE_POWER_OFF);
-	if (err) {
-		/* Set state to BT_RUNNING so resume doesn't notify */
-		hdev->suspend_state = BT_RUNNING;
-		hci_resume_sync(hdev);
-		return err;
-	}
+	if (hci_conn_count(hdev)) {
+		/* Soft disconnect everything (power off) */
+		err = hci_disconnect_all_sync(hdev, HCI_ERROR_REMOTE_POWER_OFF);
+		if (err) {
+			/* Set state to BT_RUNNING so resume doesn't notify */
+			hdev->suspend_state = BT_RUNNING;
+			hci_resume_sync(hdev);
+			return err;
+		}
 
-	/* Update event mask so only the allowed event can wakeup the host */
-	hci_set_event_mask_sync(hdev);
+		/* Update event mask so only the allowed event can wakeup the
+		 * host.
+		 */
+		hci_set_event_mask_sync(hdev);
+	}
 
 	/* Only configure accept list if disconnect succeeded and wake
 	 * isn't being prevented.