/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.hardware.bluetooth@1.0;

import IBluetoothHciCallbacks;

/**
 * The Host Controller Interface (HCI) is the layer defined by the Bluetooth
 * specification between the software that runs on the host and the Bluetooth
 * controller chip. This boundary is the natural choice for a Hardware
 * Abstraction Layer (HAL). Dealing only in HCI packets and events simplifies
 * the stack and abstracts away power management, initialization, and other
 * implementation-specific details related to the hardware.
 */

interface IBluetoothHci {
    /**
     * Initialize the underlying HCI interface.
     *
     * This method should be used to initialize any hardware interfaces
     * required to communicate with the Bluetooth hardware in the
     * device.
     *
     * The |oninitializationComplete| callback must be invoked in response
     * to this function to indicate success before any other function
     * (sendHciCommand, sendAclData, * sendScoData) is invoked on this
     * interface.
     *
     * @param callback implements IBluetoothHciCallbacks which will
     *    receive callbacks when incoming HCI packets are received
     *    from the controller to be sent to the host.
     */
    @entry
    @callflow(next={"sendHciCommand", "sendAclData", "sendScoData", "close"})
    initialize(IBluetoothHciCallbacks callback);

    /**
     * Send an HCI command (as specified in the Bluetooth Specification
     * V4.2, Vol 2, Part 5, Section 5.4.1) to the Bluetooth controller.
     * Commands must be executed in order.
     *
     * @param command is the HCI command to be sent
     */
    @callflow(next={"sendHciCommand", "sendAclData", "sendScoData", "close"})
    sendHciCommand(HciPacket command);

    /**
     * Send an HCI ACL data packet (as specified in the Bluetooth Specification
     * V4.2, Vol 2, Part 5, Section 5.4.2) to the Bluetooth controller.
     * Packets must be processed in order.
     * @param data HCI data packet to be sent
     */
    @callflow(next={"sendHciCommand", "sendAclData", "sendScoData", "close"})
    sendAclData(HciPacket data);

    /**
     * Send an SCO data packet (as specified in the Bluetooth Specification
     * V4.2, Vol 2, Part 5, Section 5.4.3) to the Bluetooth controller.
     * Packets must be processed in order.
     * @param data HCI data packet to be sent
     */
    @callflow(next={"sendHciCommand", "sendAclData", "sendScoData", "close"})
    sendScoData(HciPacket data);

    /**
     * Close the HCI interface
     */
    @exit
    close();
};