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
17 #include <stdint.h>
18 #include <math.h>
19 #include <sys/types.h>
20
21 #include <utils/Errors.h>
22
23 #include <hardware/sensors.h>
24
25 #include "GravitySensor.h"
26 #include "SensorDevice.h"
27 #include "SensorFusion.h"
28
29 namespace android {
30 // ---------------------------------------------------------------------------
31
GravitySensor(sensor_t const * list,size_t count)32 GravitySensor::GravitySensor(sensor_t const* list, size_t count)
33 : mSensorDevice(SensorDevice::getInstance()),
34 mSensorFusion(SensorFusion::getInstance())
35 {
36 for (size_t i=0 ; i<count ; i++) {
37 if (list[i].type == SENSOR_TYPE_ACCELEROMETER) {
38 mAccelerometer = Sensor(list + i);
39 break;
40 }
41 }
42 }
43
process(sensors_event_t * outEvent,const sensors_event_t & event)44 bool GravitySensor::process(sensors_event_t* outEvent,
45 const sensors_event_t& event)
46 {
47 const static double NS2S = 1.0 / 1000000000.0;
48 if (event.type == SENSOR_TYPE_ACCELEROMETER) {
49 vec3_t g;
50 if (!mSensorFusion.hasEstimate())
51 return false;
52 const mat33_t R(mSensorFusion.getRotationMatrix());
53 // FIXME: we need to estimate the length of gravity because
54 // the accelerometer may have a small scaling error. This
55 // translates to an offset in the linear-acceleration sensor.
56 g = R[2] * GRAVITY_EARTH;
57
58 *outEvent = event;
59 outEvent->data[0] = g.x;
60 outEvent->data[1] = g.y;
61 outEvent->data[2] = g.z;
62 outEvent->sensor = '_grv';
63 outEvent->type = SENSOR_TYPE_GRAVITY;
64 return true;
65 }
66 return false;
67 }
68
activate(void * ident,bool enabled)69 status_t GravitySensor::activate(void* ident, bool enabled) {
70 return mSensorFusion.activate(ident, enabled);
71 }
72
setDelay(void * ident,int,int64_t ns)73 status_t GravitySensor::setDelay(void* ident, int /*handle*/, int64_t ns) {
74 return mSensorFusion.setDelay(ident, ns);
75 }
76
getSensor() const77 Sensor GravitySensor::getSensor() const {
78 sensor_t hwSensor;
79 hwSensor.name = "Gravity Sensor";
80 hwSensor.vendor = "AOSP";
81 hwSensor.version = 3;
82 hwSensor.handle = '_grv';
83 hwSensor.type = SENSOR_TYPE_GRAVITY;
84 hwSensor.maxRange = GRAVITY_EARTH * 2;
85 hwSensor.resolution = mAccelerometer.getResolution();
86 hwSensor.power = mSensorFusion.getPowerUsage();
87 hwSensor.minDelay = mSensorFusion.getMinDelay();
88 Sensor sensor(&hwSensor);
89 return sensor;
90 }
91
92 // ---------------------------------------------------------------------------
93 }; // namespace android
94
95