Hi Sonny, > 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 <abhishekpandit@xxxxxxxxxxxx> > Signed-off-by: Sonny Sasaka <sonnysasaka@xxxxxxxxxxxx> > > --- > net/bluetooth/hci_conn.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c > index 4f1cd8063e720..b41ad08f8d411 100644 > --- a/net/bluetooth/hci_conn.c > +++ b/net/bluetooth/hci_conn.c > @@ -233,6 +233,17 @@ static void hci_acl_create_connection(struct hci_conn *conn) > else > cp.role_switch = 0x00; > > + /* 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)) > + hci_send_cmd(hdev, HCI_OP_INQUIRY_CANCEL, 0, NULL); > + while this seems acceptable, what happens when we have interleaved discovery where we toggle between BR/EDR inquiry and LE scanning. Are you sure we not better cancel the mgmt discovery completely. Regards Marcel
