platform_hardware_interfaces/camera/device/3.6/ICameraDeviceSession.hal

/*
 * Copyright (C) 2019 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.camera.device@3.6;

import android.hardware.camera.common@1.0::Status;
import @3.5::ICameraDeviceSession;
import @3.5::StreamConfiguration;
import ICameraOfflineSession;

/**
 * Camera device active session interface.
 *
 * Obtained via ICameraDevice::open(), this interface contains the methods to
 * configure and request captures from an active camera device.
 */
interface ICameraDeviceSession extends @3.5::ICameraDeviceSession {
    /**
     * configureStreams_3_6:
     *
     * Identical to @3.5::ICameraDeviceSession.configureStreams, except that:
     *
     * - a boolean supportOffline is added to HalStreamConfiguration to indicate
     *   if this stream can be switched to offline mode later.
     *
     * @return status Status code for the operation, one of:
     *     OK:
     *         On successful stream configuration.
     *     INTERNAL_ERROR:
     *         If there has been a fatal error and the device is no longer
     *         operational. Only close() can be called successfully by the
     *         framework after this error is returned.
     *     ILLEGAL_ARGUMENT:
     *         If the requested stream configuration is invalid. Some examples
     *         of invalid stream configurations include:
     *           - Including more than 1 INPUT stream
     *           - Not including any OUTPUT streams
     *           - Including streams with unsupported formats, or an unsupported
     *             size for that format.
     *           - Including too many output streams of a certain format.
     *           - Unsupported rotation configuration
     *           - Stream sizes/formats don't satisfy the
     *             StreamConfigurationMode requirements
     *             for non-NORMAL mode, or the requested operation_mode is not
     *             supported by the HAL.
     *           - Unsupported usage flag
     *         The camera service cannot filter out all possible illegal stream
     *         configurations, since some devices may support more simultaneous
     *         streams or larger stream resolutions than the minimum required
     *         for a given camera device hardware level. The HAL must return an
     *         ILLEGAL_ARGUMENT for any unsupported stream set, and then be
     *         ready to accept a future valid stream configuration in a later
     *         configureStreams call.
     * @return halConfiguration The stream parameters desired by the HAL for
     *     each stream, including maximum buffers, the usage flags, and the
     *     override format.
     */
    configureStreams_3_6(@3.5::StreamConfiguration requestedConfiguration)
        generates (Status status, HalStreamConfiguration halConfiguration);

    /**
     * switchToOffline:
     *
     * Switch the current running session from actively streaming mode to the
     * offline mode. See ICameraOfflineSession for more details.
     *
     * The streamsToKeep argument contains list of streams IDs where application
     * still needs its output. For all streams application does not need anymore,
     * camera HAL can send ERROR_BUFFER to speed up the transition, or even send
     * ERROR_REQUEST if all output targets of a request is not needed. By the
     * time this call returns, camera HAL must have returned all buffers coming
     * from streams no longer needed and have erased buffer caches of such streams.
     *
     * For all requests that are going to be transferred to offline session,
     * the ICameraDeviceSession is responsible to capture all input buffers from
     * the image sensor before the switchToOffline call returns. Before
     * switchToOffline returns, camera HAL must have completed all requests not
     * switching to offline mode, and collected information on what streams and
     * requests are going to continue in the offline session, in the
     * offlineSessionInfo output argument.
     *
     * If there are no requests qualified to be transferred to offline session,
     * the camera HAL must return a null ICameraOfflineSession object with OK
     * status. In this scenario, the camera HAL still must flush all inflight
     * requests and unconfigure all streams before returning this call.
     *
     * After switchToOffline returns, the ICameraDeviceSession must be back to
     * unconfigured state as if it is just created and no streams are configured.
     * Also, camera HAL must not call any methods in ICameraDeviceCallback since
     * all unfinished requests are now transferred to the offline session.
     * After the call returns, camera service may then call close to close
     * the camera device, or call configureStream* again to reconfigure the
     * camera and then send new capture requests with processCaptureRequest. In
     * the latter case, it is legitimate for camera HAL to call methods in
     * ICameraDeviceCallback again in response to the newly submitted capture
     * requests.
     *
     * @return status Status code for the operation, one of:
     *     OK:
     *         On switching to offline session and unconfiguring streams
     *         successfully.
     *     ILLEGAL_ARGUMENT:
     *         If camera does not support offline mode in any one of streams
     *         in streamsToKeep argument. Note that the camera HAL must report
     *         if a stream supports offline mode in HalStreamConfiguration
     *         output of configureStreams_3_6 method. If all streams in
     *         streamsToKeep argument support offline mode, then the camera HAL
     *         must not return this error.
     *
     *
     * @return offlineSessionInfo Information on what streams and requests will
     *     be transferred to offline session to continue processing.
     *
     * @return offlineSession The offline session object camera service will use
     *     to interact with.
     */
    switchToOffline(vec<int32_t> streamsToKeep) generates (Status status,
        CameraOfflineSessionInfo offlineSessionInfo, ICameraOfflineSession offlineSession);
};