camera/device/3.2/ICameraDevice.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.camera.device@3.2;

import android.hardware.camera.common@1.0::types;
import ICameraDeviceSession;
import ICameraDeviceCallback;

/**
 * Camera device HAL, first modern version
 *
 * Supports the android.hardware.Camera API, and the android.hardware.camera2
 * API at LIMITED or better hardware level.
 *
 */
interface ICameraDevice {

    /**
     * Get camera device resource cost information.
     *
     * @return status Status code for the operation, one of:
     *     OK:
     *         On success
     *     INTERNAL_ERROR:
     *         An unexpected internal camera HAL error occurred, and the
     *         resource cost is not available.
     *     CAMERA_DISCONNECTED:
     *         An external camera device has been disconnected, and is no longer
     *         available. This camera device interface is now stale, and a new
     *         instance must be acquired if the device is reconnected. All
     *         subsequent calls on this interface must return
     *         CAMERA_DISCONNECTED.
     * @return resourceCost
     *     The resources required to open this camera device, or unspecified
     *     values if status is not OK.
     */
    getResourceCost() generates (Status status, CameraResourceCost resourceCost);

    /**
     * getCameraCharacteristics:
     *
     * Return the static camera information for this camera device. This
     * information may not change between consecutive calls.
     *
     * When an external camera is disconnected, its camera id becomes
     * invalid. Calling this method with this invalid camera id must result in
     * ILLEGAL_ARGUMENT; this may happen even before the device status callback
     * is invoked by the HAL.
     *
     * @return status Status code for the operation, one of:
     *     OK:
     *         On a successful open of the camera device.
     *     INTERNAL_ERROR:
     *         The camera device cannot be opened due to an internal
     *         error.
     *     CAMERA_DISCONNECTED:
     *         An external camera device has been disconnected, and is no longer
     *         available. This camera device interface is now stale, and a new
     *         instance must be acquired if the device is reconnected. All
     *         subsequent calls on this interface must return
     *         CAMERA_DISCONNECTED.
     *
     * @return cameraCharacteristics
     *     The static metadata for this camera device, or an empty metadata
     *     structure if status is not OK.
     *
     */
    getCameraCharacteristics() generates
            (Status status, CameraMetadata cameraCharacteristics);

    /**
     * setTorchMode:
     *
     * Turn on or off the torch mode of the flash unit associated with this
     * camera device. If the operation is successful, HAL must notify the
     * framework torch state by invoking
     * ICameraProviderCallback::torchModeStatusChange() with the new state.
     *
     * An active camera session has a higher priority accessing the flash
     * unit. When there are any resource conflicts, such as when open() is
     * called to fully activate a camera device, the provider must notify the
     * framework through ICameraProviderCallback::torchModeStatusChange() that
     * the torch mode has been turned off and the torch mode state has become
     * TORCH_MODE_STATUS_NOT_AVAILABLE. When resources to turn on torch mode
     * become available again, the provider must notify the framework through
     * ICameraProviderCallback::torchModeStatusChange() that the torch mode
     * state has become TORCH_MODE_STATUS_AVAILABLE_OFF for set_torch_mode() to
     * be called.
     *
     * When the client calls setTorchMode() to turn on the torch mode of a flash
     * unit, if the HAL cannot keep multiple torch modes on simultaneously, the
     * HAL must turn off the torch mode(s) that were turned on by previous
     * setTorchMode() calls and notify the framework that the torch mode state
     * of those flash unit(s) has become TORCH_MODE_STATUS_AVAILABLE_OFF.
     *
     * @param torchMode The new mode to set the device flash unit to.
     *
     * @return status Status code for the operation, one of:
     *     OK:
     *         On a successful change to the torch state
     *     INTERNAL_ERROR:
     *         The flash unit cannot be operated due to an unexpected internal
     *         error.
     *     ILLEGAL_ARGUMENT:
     *         The camera ID is unknown.
     *     CAMERA_IN_USE:
     *         This camera device has been opened, so the torch cannot be
     *         controlled until it is closed.
     *     MAX_CAMERAS_IN_USE:
     *         Due to other camera devices being open, or due to other
     *         resource constraints, the torch cannot be controlled currently.
     *     METHOD_NOT_SUPPORTED:
     *         This provider does not support direct operation of flashlight
     *         torch mode. The framework must open the camera device and turn
     *         the torch on through the device interface.
     *     OPERATION_NOT_SUPPORTED:
     *         This camera device does not have a flash unit. This can
     *         be returned if and only if android.flash.info.available is
     *         false.
     *     CAMERA_DISCONNECTED:
     *         An external camera device has been disconnected, and is no longer
     *         available. This camera device interface is now stale, and a new
     *         instance must be acquired if the device is reconnected. All
     *         subsequent calls on this interface must return
     *         CAMERA_DISCONNECTED.
     *
     */
    setTorchMode(TorchMode mode) generates (Status status);

    /**
     * open:
     *
     * Power on and initialize this camera device for active use, returning a
     * session handle for active operations.
     *
     * @param callback Interface to invoke by the HAL for device asynchronous
     *     events.
     * @return status Status code for the operation, one of:
     *     OK:
     *         On a successful open of the camera device.
     *     INTERNAL_ERROR:
     *         The camera device cannot be opened due to an internal
     *         error.
     *     ILLEGAL_ARGUMENT:
     *         The callbacks handle is invalid (for example, it is null).
     *     CAMERA_IN_USE:
     *         This camera device is already open.
     *     MAX_CAMERAS_IN_USE:
     *         The maximal number of camera devices that can be
     *         opened concurrently were opened already.
     *     CAMERA_DISCONNECTED:
     *         This external camera device has been disconnected, and is no
     *         longer available. This interface is now stale, and a new instance
     *         must be acquired if the device is reconnected. All subsequent
     *         calls on this interface must return CAMERA_DISCONNECTED.
     * @return session The interface to the newly-opened camera session,
     *     or null if status is not OK.
     */
    open(ICameraDeviceCallback callback) generates
            (Status status, ICameraDeviceSession session);

    /**
     * dumpState:
     *
     * Print out debugging state for the camera device. This may be called by
     * the framework when the camera service is asked for a debug dump, which
     * happens when using the dumpsys tool, or when capturing a bugreport.
     *
     * The passed-in file descriptor can be used to write debugging text using
     * dprintf() or write(). The text must be in ASCII encoding only.
     *
     * In case this camera device has been disconnected, the dump must not fail,
     * but may simply print out 'Device disconnected' or equivalent.
     *
     * Performance requirements:
     *
     * This must be a non-blocking call. The HAL should return from this call
     * in 1ms, must return from this call in 10ms. This call must avoid
     * deadlocks, as it may be called at any point during camera operation.
     * Any synchronization primitives used (such as mutex locks or semaphores)
     * must be acquired with a timeout.
     */
    dumpState(handle fd);

};