vehicle/2.0/IVehicle.hal

/*
 * 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.vehicle@2.0;

import IVehicleCallback;

interface IVehicle {
  /**
   * Returns a list of all property configurations supported by this vehicle
   * HAL.
   */
  getAllPropConfigs() generates (vec<VehiclePropConfig> propConfigs);

  /*
   * Returns a list of property configurations for given properties.
   */
  getPropConfigs(vec<VehicleProperty> props)
          generates (vec<VehiclePropConfig> propConfigs);

  /**
   * Get a vehicle property value.
   *
   * For VehiclePropertyChangeMode::STATIC properties, this method must always
   * return the same value always.
   * For VehiclePropertyChangeMode::ON_CHANGE properties, it must return the
   * latest available value.
   *
   * If there is no data available yet, which can happen during initial stage,
   * this call must return immediately with an error code of
   * StatusCode::TRY_AGAIN.
   */
  get(VehicleProperty propId, int32_t areaId)
          generates (StatusCode status, VehiclePropValue propValue);

  /**
   * Set a vehicle property value.
   *
   * Timestamp of data must be ignored for set operation.
   *
   * Setting some properties require having initial state available. If initial
   * data is not available yet this call must return StatusCode::TRY_AGAIN.
   * For a property with separate power control this call must return
   * StatusCode::NOT_AVAILABLE error if property is not powered on.
   */
  set(VehiclePropValue propValue) generates (StatusCode status);

  /**
   * Subscribes to property events.
   *
   * Clients must be able to subscribe to multiple properties at a time
   * depending on data provided in options argument.
   *
   * @param listener This client must be called on appropriate event.
   * @param options List of options to subscribe. SubscribeOption contains
   *                information such as property Id, area Id, sample rate, etc.
   */
  subscribe(IVehicleCallback callback, vec<SubscribeOptions> options)
          generates (StatusCode status);

  /**
   * Unsubscribes from property events.
   *
   * If this client wasn't subscribed to the given property, this method
   * must return StatusCode::INVALID_ARGUMENT.
   */
  unsubscribe(IVehicleCallback callback, VehicleProperty propId)
          generates (StatusCode status);

  /**
   * Print out debugging state for the vehicle hal.
   *
   * The text must be in ASCII encoding only.
   *
   * Performance requirements:
   *
   * The HAL must return from this call in less than 10ms. This call must avoid
   * deadlocks, as it may be called at any point of operation. Any synchronization
   * primitives used (such as mutex locks or semaphores) must be acquired
   * with a timeout.
   *
   * TODO(pavelm): we cannot use handle here due to Java compatibility, it's
   * better to pass file descriptor and write debug data directly in vehicle HAL
   * rather than passing back a string.
   */
  debugDump() generates (string s);
};