/*
 * Copyright 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.wifi@1.0;

import IWifiChip;
import IWifiEventCallback;

/**
 * This is the root of the HAL module and is the interface returned when
 * loading an implementation of the Wi-Fi HAL. There must be at most one
 * module loaded in the system.
 */
interface IWifi {
  /**
   * Requests notifications of significant events for the HAL. Multiple calls to
   * this must register multiple callbacks each of which must receive all
   * events. |IWifiEventCallback| object registration must be independent of the
   * state of the rest of the HAL and must persist though stops/starts. These
   * objects must be deleted when the corresponding client process is dead.
   *
   * @param callback An instance of the |IWifiEventCallback| HIDL interface
   *        object.
   * @return status WifiStatus of the operation.
   *         Possible status codes:
   *         |WifiStatusCode.SUCCESS|,
   *         |WifiStatusCode.UNKNOWN|
   */
  @entry
  @callflow(next={"*"})
  registerEventCallback(IWifiEventCallback callback)
      generates (WifiStatus status);

  /**
   * Get the current state of the HAL.
   *
   * @return started true if started, false otherwise.
   */
  isStarted() generates (bool started);

  /**
   * Perform any setup that is required to make use of the module. If the module
   * is already started then this must be a noop.
   * Must trigger |IWifiEventCallback.onStart| on success.
   *
   * @return status WifiStatus of the operation.
   *         Possible status codes:
   *         |WifiStatusCode.SUCCESS|,
   *         |WifiStatusCode.NOT_AVAILABLE|,
   *         |WifiStatusCode.UNKNOWN|
   */
  @entry
  @callflow(next={"registerEventCallback", "start", "stop", "getChip"})
  start() generates (WifiStatus status);

  /**
   * Tear down any state, ongoing commands, etc. If the module is already
   * stopped then this must be a noop. If the HAL is already stopped or it
   * succeeds then onStop must be called. After calling this all IWifiChip
   * objects will be considered invalid.
   * Must trigger |IWifiEventCallback.onStop| on success.
   * Must trigger |IWifiEventCallback.onFailure| on failure.
   *
   * Calling stop then start is a valid way of resetting state in the HAL,
   * driver, firmware.
   *
   * @return status WifiStatus of the operation.
   *         Possible status codes:
   *         |WifiStatusCode.SUCCESS|,
   *         |WifiStatusCode.NOT_STARTED|,
   *         |WifiStatusCode.UNKNOWN|
   */
  @exit
  @callflow(next={"registerEventCallback", "start", "stop"})
  stop() generates (WifiStatus status);

  /**
   * Retrieve the list of all chip Id's on the device.
   * The corresponding |IWifiChip| object for any chip can be
   * retrieved using |getChip| method.
   *
   * @return status WifiStatus of the operation.
   *         Possible status codes:
   *         |WifiStatusCode.SUCCESS|,
   *         |WifiStatusCode.NOT_STARTED|,
   *         |WifiStatusCode.UNKNOWN|
   * @return chipIds List of all chip Id's on the device.
   */
  @callflow(next={"*"})
  getChipIds() generates (WifiStatus status, vec<ChipId> chipIds);

  /**
   * Gets a HIDL interface object for the chip corresponding to the
   * provided chipId.
   *
   * @return status WifiStatus of the operation.
   *         Possible status codes:
   *         |WifiStatusCode.SUCCESS|,
   *         |WifiStatusCode.NOT_STARTED|,
   *         |WifiStatusCode.UNKNOWN|
   * @return chip HIDL interface object representing the chip.
   */
  @callflow(next={"*"})
  getChip(ChipId chipId) generates (WifiStatus status, IWifiChip chip);
};