From 89e65975fea5c25706e8cc3a89f9f97b20fc45ad Mon Sep 17 00:00:00 2001 From: Sonny Sasaka Date: Wed, 9 Dec 2020 13:35:14 -0800 Subject: [PATCH] Bluetooth: Cancel Inquiry before Create Connection Many controllers do not allow HCI Create Connection while it is doing Inquiry. This patch adds Inquiry Cancel before Create Connection in this case to allow the controller to do Create Connection. User space will be aware of this Inquiry cancellation and they may issue another discovery request afterwards. Sample Command Disallowed response of HCI Create Connection: < HCI Command: Inquiry (0x01|0x0001) plen 5 Access code: 0x9e8b33 (General Inquiry) Length: 10.24s (0x08) Num responses: 0 > HCI Event: Command Status (0x0f) plen 4 Inquiry (0x01|0x0001) ncmd 2 Status: Success (0x00) < HCI Command: Create Connection (0x01|0x0005) plen 13 Address: XX:XX:XX:XX:XX:XX Packet type: 0xcc18 Page scan repetition mode: R2 (0x02) Page scan mode: Mandatory (0x00) Clock offset: 0x0000 Role switch: Allow slave (0x01) > HCI Event: Command Status (0x0f) plen 4 Create Connection (0x01|0x0005) ncmd 1 Status: Success (0x00) > HCI Event: Connect Complete (0x03) plen 11 Status: Command Disallowed (0x0c) Handle: 65535 Address: XX:XX:XX:XX:XX:XX Link type: ACL (0x01) Encryption: Disabled (0x00) Reviewed-by: Abhishek Pandit-Subedi Reviewed-by: Alain Michaud Signed-off-by: Sonny Sasaka Signed-off-by: Marcel Holtmann --- net/bluetooth/hci_conn.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 4f1cd8063e72..23c0d77ea737 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -203,6 +203,23 @@ static void hci_acl_create_connection(struct hci_conn *conn) BT_DBG("hcon %p", conn); + /* Many controllers disallow HCI Create Connection while it is doing + * HCI Inquiry. So we cancel the Inquiry first before issuing HCI Create + * Connection. This may cause the MGMT discovering state to become false + * without user space's request but it is okay since the MGMT Discovery + * APIs do not promise that discovery should be done forever. Instead, + * the user space monitors the status of MGMT discovering and it may + * request for discovery again when this flag becomes false. + */ + if (test_bit(HCI_INQUIRY, &hdev->flags)) { + /* Put this connection to "pending" state so that it will be + * executed after the inquiry cancel command complete event. + */ + conn->state = BT_CONNECT2; + hci_send_cmd(hdev, HCI_OP_INQUIRY_CANCEL, 0, NULL); + return; + } + conn->state = BT_CONNECT; conn->out = true; conn->role = HCI_ROLE_MASTER;