/*
* Copyright (C) 2018 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.
*/
#ifndef ANDROID_ML_NN_RUNTIME_VERSIONED_IDEVICE_H
#define ANDROID_ML_NN_RUNTIME_VERSIONED_IDEVICE_H
#include "HalInterfaces.h"
#include <android-base/macros.h>
#include <string>
#include <tuple>
namespace android {
namespace nn {
/**
* This object is either a V1_1::IDevice or V1_0::IDevice object. This class
* abstracts away version differences, allowing the remainder of the runtime to
* always use the most up-to-date version of all HIDL types. As such, any
* reference to a HIDL type in the rest of the runtime will--by default--be the
* latest HIDL version.
*
* This class will attempt to call the latest version of each interface method
* if possible. If the latest method is unavailable, the VersionedIDevice class
* will attempt to upcast the type (e.g., V1_1::Model to V1_0::Model), and
* invoke the latest interface method possible. If the VersionedIDevice class
* fails to find a matching applicable function, it will return an error.
*/
class VersionedIDevice {
DISALLOW_IMPLICIT_CONSTRUCTORS(VersionedIDevice);
public:
/**
* Constructor for the VersionedIDevice object.
*
* VersionedIDevice is constructed with the V1_0::IDevice object, which
* represents a device that is at least v1.0 of the interface. The
* constructor downcasts to the latest version of the IDevice interface, and
* will default to using the latest version of all IDevice interface
* methods automatically.
*
* @param device A device object that is least version 1.0 of the IDevice
* interface.
*/
VersionedIDevice(sp<V1_0::IDevice> device);
/**
* Gets the capabilities of a driver.
*
* @return status Error status of the call, must be:
* - NONE if successful
* - DEVICE_UNAVAILABLE if driver is offline or busy
* - GENERAL_FAILURE if there is an unspecified error
* @return capabilities Capabilities of the driver.
*/
std::pair<ErrorStatus, Capabilities> getCapabilities();
/**
* Gets the supported operations in a model.
*
* getSupportedSubgraph indicates which operations of a model are fully
* supported by the vendor driver. If an operation may not be supported for
* any reason, getSupportedOperations must return false for that operation.
*
* @param model A model whose operations--and their corresponding
* operands--are to be verified by the driver.
* @return status Error status of the call, must be:
* - NONE if successful
* - DEVICE_UNAVAILABLE if driver is offline or busy
* - GENERAL_FAILURE if there is an unspecified error
* - INVALID_ARGUMENT if provided model is invalid
* @return supportedOperations A list of supported operations, where true
* indicates the operation is supported and
* false indicates the operation is not
* supported. The index of "supported"
* corresponds with the index of the operation
* it is describing.
*/
std::pair<ErrorStatus, hidl_vec<bool>> getSupportedOperations(const Model& model);
/**
* Creates a prepared model for execution.
*
* prepareModel is used to make any necessary transformations or alternative
* representations to a model for execution, possiblly including
* transformations on the constant data, optimization on the model's graph,
* or compilation into the device's native binary format. The model itself
* is not changed.
*
* The model is prepared asynchronously with respect to the caller. The
* prepareModel function must verify the inputs to the prepareModel function
* are correct. If there is an error, prepareModel must immediately invoke
* the callback with the appropriate ErrorStatus value and nullptr for the
* IPreparedModel, then return with the same ErrorStatus. If the inputs to
* the prepareModel function are valid and there is no error, prepareModel
* must launch an asynchronous task to prepare the model in the background,
* and immediately return from prepareModel with ErrorStatus::NONE. If the
* asynchronous task fails to launch, prepareModel must immediately invoke
* the callback with ErrorStatus::GENERAL_FAILURE and nullptr for the
* IPreparedModel, then return with ErrorStatus::GENERAL_FAILURE.
*
* When the asynchronous task has finished preparing the model, it must
* immediately invoke the callback function provided as an input to
* prepareModel. If the model was prepared successfully, the callback object
* must be invoked with an error status of ErrorStatus::NONE and the
* produced IPreparedModel object. If an error occurred preparing the model,
* the callback object must be invoked with the appropriate ErrorStatus
* value and nullptr for the IPreparedModel.
*
* The only information that may be unknown to the model at this stage is
* the shape of the tensors, which may only be known at execution time. As
* such, some driver services may return partially prepared models, where
* the prepared model can only be finished when it is paired with a set of
* inputs to the model. Note that the same prepared model object can be
* used with different shapes of inputs on different (possibly concurrent)
* executions.
*
* Multiple threads can call prepareModel on the same model concurrently.
*
* @param model The model to be prepared for execution.
* @param callback A callback object used to return the error status of
* preparing the model for execution and the prepared model
* if successful, nullptr otherwise. The callback object's
* notify function must be called exactly once, even if the
* model could not be prepared.
* @return status Error status of launching a task which prepares the model
* in the background; must be:
* - NONE if preparation task is successfully launched
* - DEVICE_UNAVAILABLE if driver is offline or busy
* - GENERAL_FAILURE if there is an unspecified error
* - INVALID_ARGUMENT if one of the input arguments is
* invalid
*/
ErrorStatus prepareModel(const Model& model, ExecutionPreference preference,
const sp<IPreparedModelCallback>& callback);
/**
* Returns the current status of a driver.
*
* @return status Status of the driver, one of:
* - DeviceStatus::AVAILABLE
* - DeviceStatus::BUSY
* - DeviceStatus::OFFLINE
* - DeviceStatus::UNKNOWN
*/
DeviceStatus getStatus();
/**
* Returns whether this handle to an IDevice object is valid or not.
*
* @return bool true if V1_0::IDevice (which could be V1_1::IDevice) is
* valid, false otherwise.
*/
bool operator!=(nullptr_t);
/**
* Returns whether this handle to an IDevice object is valid or not.
*
* @return bool true if V1_0::IDevice (which could be V1_1::IDevice) is
* invalid, false otherwise.
*/
bool operator==(nullptr_t);
private:
/**
* Both versions of IDevice are necessary because the driver could be v1.0,
* v1.1, or a later version. These two pointers logically represent the same
* object.
*
* The general strategy is: HIDL returns a V1_0 device object, which
* (if not nullptr) could be v1.0, v1.1, or a greater version. The V1_0
* object is then "dynamically cast" to a V1_1 object. If successful,
* mDeviceV1_1 will point to the same object as mDeviceV1_0; otherwise,
* mDeviceV1_1 will be nullptr.
*
* In general:
* * If the device is truly v1.0, mDeviceV1_0 will point to a valid object
* and mDeviceV1_1 will be nullptr.
* * If the device is truly v1.1 or later, both mDeviceV1_0 and mDeviceV1_1
* will point to the same valid object.
*
* Idiomatic usage: if mDeviceV1_1 is non-null, do V1_1 dispatch; otherwise,
* do V1_0 dispatch.
*/
sp<V1_0::IDevice> mDeviceV1_0;
sp<V1_1::IDevice> mDeviceV1_1;
};
} // namespace nn
} // namespace android
#endif // ANDROID_ML_NN_RUNTIME_VERSIONED_IDEVICE_H