Bluetooth: Add a new HCI_USE_DEBUG_KEYS flag

To pave the way for actively using debug keys for pairing this patch
adds a new HCI_USE_DEBUG_KEYS flag for the purpose. When the flag is set
we issue a HCI_Write_SSP_Debug mode whenever HCI_Write_SSP_Mode(0x01)
has been issued as well as before issuing a HCI_Write_SSP_Mode(0x00)
command.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 747746b..69afbb2 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -1877,6 +1877,10 @@
 		goto failed;
 	}
 
+	if (!cp->val && test_bit(HCI_USE_DEBUG_KEYS, &hdev->dev_flags))
+		hci_send_cmd(hdev, HCI_OP_WRITE_SSP_DEBUG_MODE,
+			     sizeof(cp->val), &cp->val);
+
 	err = hci_send_cmd(hdev, HCI_OP_WRITE_SSP_MODE, 1, &cp->val);
 	if (err < 0) {
 		mgmt_pending_remove(cmd);
@@ -5784,10 +5788,14 @@
 
 	hci_req_init(&req, hdev);
 
-	if (test_bit(HCI_SSP_ENABLED, &hdev->dev_flags))
+	if (test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) {
+		if (test_bit(HCI_USE_DEBUG_KEYS, &hdev->dev_flags))
+			hci_req_add(&req, HCI_OP_WRITE_SSP_DEBUG_MODE,
+				    sizeof(enable), &enable);
 		update_eir(&req);
-	else
+	} else {
 		clear_eir(&req);
+	}
 
 	hci_req_run(&req, NULL);
 }