/* Calculates the largest ACL payload that the controller can accept.  */
static uint16_t ble_hs_hci_max_acl_payload_sz(struct ble_hs_conn *conn)
/* Calculates the largest ACL payload that the controller can accept.  */
static uint16_t ble_hs_hci_max_acl_payload_sz(struct ble_hs_conn *conn)
{
    return conn->tx_ll_mtu;
    if(conn->supported_feat&BLE_HS_HCI_LE_FEAT_DATA_PACKET_LENGTH_EXT)
    {
        return ble_hs_hci_buf_sz;
    }else
    {
        return 27;
    }
}