hci_find_ltk
struct smp_ltk *hci_find_ltk(struct hci_dev *hdev, bdaddr_t *bdaddr,
ltk = hci_find_ltk(conn->hdev, &conn->dst, conn->dst_type,
old_key = hci_find_ltk(hdev, bdaddr, addr_type, role);
ltk = hci_find_ltk(hdev, &conn->dst, conn->dst_type, conn->role);
key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))