SensorEventQueue.cpp revision 589ce85ee4174829cfedce91b6b2509d2a4002eb 
1/*
2 * Copyright (C) 2010 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#include <stdint.h>
17#include <sys/types.h>
18
19#include <utils/Errors.h>
20#include <utils/RefBase.h>
21
22#include <gui/Sensor.h>
23#include <gui/SensorChannel.h>
24#include <gui/SensorEventQueue.h>
25#include <gui/ISensorEventConnection.h>
26
27#include <android/sensor.h>
28
29// ----------------------------------------------------------------------------
30namespace android {
31// ----------------------------------------------------------------------------
32
33SensorEventQueue::SensorEventQueue(const sp<ISensorEventConnection>& connection)
34    : mSensorEventConnection(connection)
35{
36}
37
38SensorEventQueue::~SensorEventQueue()
39{
40}
41
42void SensorEventQueue::onFirstRef()
43{
44    mSensorChannel = mSensorEventConnection->getSensorChannel();
45}
46
47int SensorEventQueue::getFd() const
48{
49    return mSensorChannel->getFd();
50}
51
52ssize_t SensorEventQueue::write(ASensorEvent const* events, size_t numEvents)
53{
54    ssize_t size = mSensorChannel->write(events, numEvents * sizeof(events[0]));
55    if (size >= 0) {
56        if (size % sizeof(events[0])) {
57            // partial write!!! should never happen.
58            return -EINVAL;
59        }
60        // returns number of events written
61        size /= sizeof(events[0]);
62    }
63    return size;
64}
65
66ssize_t SensorEventQueue::read(ASensorEvent* events, size_t numEvents)
67{
68    ssize_t size = mSensorChannel->read(events, numEvents*sizeof(events[0]));
69    if (size >= 0) {
70        if (size % sizeof(events[0])) {
71            // partial write!!! should never happen.
72            return -EINVAL;
73        }
74        // returns number of events read
75        size /= sizeof(events[0]);
76    }
77    return size;
78}
79
80status_t SensorEventQueue::enableSensor(Sensor const* sensor) const
81{
82    return mSensorEventConnection->enableDisable(sensor->getHandle(), true);
83}
84
85status_t SensorEventQueue::disableSensor(Sensor const* sensor) const
86{
87    return mSensorEventConnection->enableDisable(sensor->getHandle(), false);
88}
89
90status_t SensorEventQueue::setEventRate(Sensor const* sensor, nsecs_t ns) const
91{
92    return mSensorEventConnection->setEventRate(sensor->getHandle(), ns);
93}
94
95// ----------------------------------------------------------------------------
96}; // namespace android
97
98