1/*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.hardware.neuralnetworks@1.0;
18
19import IPreparedModelCallback;
20
21/**
22 * This interface represents a device driver.
23 */
24interface IDevice {
25    /**
26     * Gets the capabilities of a driver.
27     *
28     * @return status Error status of the call, must be:
29     *                - NONE if successful
30     *                - DEVICE_UNAVAILABLE if driver is offline or busy
31     *                - GENERAL_FAILURE if there is an unspecified error
32     * @return capabilities Capabilities of the driver.
33     */
34    getCapabilities() generates (ErrorStatus status, Capabilities capabilities);
35
36    /**
37     * Gets the supported operations in a model.
38     *
39     * getSupportedOperations indicates which operations of a model are fully
40     * supported by the vendor driver. If an operation may not be supported for
41     * any reason, getSupportedOperations must return false for that operation.
42     *
43     * @param model A model whose operations--and their corresponding
44     *              operands--are to be verified by the driver.
45     * @return status Error status of the call, must be:
46     *                - NONE if successful
47     *                - DEVICE_UNAVAILABLE if driver is offline or busy
48     *                - GENERAL_FAILURE if there is an unspecified error
49     *                - INVALID_ARGUMENT if provided model is invalid
50     * @return supportedOperations A list of supported operations, where true
51     *                             indicates the operation is supported and
52     *                             false indicates the operation is not
53     *                             supported. The index of "supported"
54     *                             corresponds with the index of the operation
55     *                             it is describing.
56     */
57    getSupportedOperations(Model model)
58                generates (ErrorStatus status, vec<bool> supportedOperations);
59
60    /**
61     * Creates a prepared model for execution.
62     *
63     * prepareModel is used to make any necessary transformations or alternative
64     * representations to a model for execution, possiblly including
65     * transformations on the constant data, optimization on the model's graph,
66     * or compilation into the device's native binary format. The model itself
67     * is not changed.
68     *
69     * The model is prepared asynchronously with respect to the caller. The
70     * prepareModel function must verify the inputs to the prepareModel function
71     * are correct. If there is an error, prepareModel must immediately invoke
72     * the callback with the appropriate ErrorStatus value and nullptr for the
73     * IPreparedModel, then return with the same ErrorStatus. If the inputs to
74     * the prepareModel function are valid and there is no error, prepareModel
75     * must launch an asynchronous task to prepare the model in the background,
76     * and immediately return from prepareModel with ErrorStatus::NONE. If the
77     * asynchronous task fails to launch, prepareModel must immediately invoke
78     * the callback with ErrorStatus::GENERAL_FAILURE and nullptr for the
79     * IPreparedModel, then return with ErrorStatus::GENERAL_FAILURE.
80     *
81     * When the asynchronous task has finished preparing the model, it must
82     * immediately invoke the callback function provided as an input to
83     * prepareModel. If the model was prepared successfully, the callback object
84     * must be invoked with an error status of ErrorStatus::NONE and the
85     * produced IPreparedModel object. If an error occurred preparing the model,
86     * the callback object must be invoked with the appropriate ErrorStatus
87     * value and nullptr for the IPreparedModel.
88     *
89     * The only information that may be unknown to the model at this stage is
90     * the shape of the tensors, which may only be known at execution time. As
91     * such, some driver services may return partially prepared models, where
92     * the prepared model can only be finished when it is paired with a set of
93     * inputs to the model. Note that the same prepared model object can be
94     * used with different shapes of inputs on different (possibly concurrent)
95     * executions.
96     *
97     * Multiple threads can call prepareModel on the same model concurrently.
98     *
99     * @param model The model to be prepared for execution.
100     * @param callback A callback object used to return the error status of
101     *                 preparing the model for execution and the prepared model
102     *                 if successful, nullptr otherwise. The callback object's
103     *                 notify function must be called exactly once, even if the
104     *                 model could not be prepared.
105     * @return status Error status of launching a task which prepares the model
106     *                in the background; must be:
107     *                - NONE if preparation task is successfully launched
108     *                - DEVICE_UNAVAILABLE if driver is offline or busy
109     *                - GENERAL_FAILURE if there is an unspecified error
110     *                - INVALID_ARGUMENT if one of the input arguments is
111     *                  invalid
112     */
113    prepareModel(Model model, IPreparedModelCallback callback)
114      generates (ErrorStatus status);
115
116    /**
117     * Returns the current status of a driver.
118     *
119     * @return status Status of the driver, one of:
120     *                - DeviceStatus::AVAILABLE
121     *                - DeviceStatus::BUSY
122     *                - DeviceStatus::OFFLINE
123     *                - DeviceStatus::UNKNOWN
124     */
125    getStatus() generates (DeviceStatus status);
126};
127