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 32 GravitySensor::GravitySensor(sensor_t const* list, size_t count) { 33 for (size_t i=0 ; i<count ; i++) { 34 if (list[i].type == SENSOR_TYPE_ACCELEROMETER) { 35 mAccelerometer = Sensor(list + i); 36 break; 37 } 38 } 39 40 const sensor_t sensor = { 41 .name = "Gravity Sensor", 42 .vendor = "AOSP", 43 .version = 3, 44 .handle = '_grv', 45 .type = SENSOR_TYPE_GRAVITY, 46 .maxRange = GRAVITY_EARTH * 2, 47 .resolution = mAccelerometer.getResolution(), 48 .power = mSensorFusion.getPowerUsage(), 49 .minDelay = mSensorFusion.getMinDelay(), 50 }; 51 mSensor = Sensor(&sensor); 52 } 53 54 bool GravitySensor::process(sensors_event_t* outEvent, 55 const sensors_event_t& event) 56 { 57 if (event.type == SENSOR_TYPE_ACCELEROMETER) { 58 vec3_t g; 59 if (!mSensorFusion.hasEstimate(FUSION_NOMAG)) 60 return false; 61 const mat33_t R(mSensorFusion.getRotationMatrix(FUSION_NOMAG)); 62 // FIXME: we need to estimate the length of gravity because 63 // the accelerometer may have a small scaling error. This 64 // translates to an offset in the linear-acceleration sensor. 65 g = R[2] * GRAVITY_EARTH; 66 67 *outEvent = event; 68 outEvent->data[0] = g.x; 69 outEvent->data[1] = g.y; 70 outEvent->data[2] = g.z; 71 outEvent->sensor = '_grv'; 72 outEvent->type = SENSOR_TYPE_GRAVITY; 73 return true; 74 } 75 return false; 76 } 77 78 status_t GravitySensor::activate(void* ident, bool enabled) { 79 return mSensorFusion.activate(FUSION_NOMAG, ident, enabled); 80 } 81 82 status_t GravitySensor::setDelay(void* ident, int /*handle*/, int64_t ns) { 83 return mSensorFusion.setDelay(FUSION_NOMAG, ident, ns); 84 } 85 86 // --------------------------------------------------------------------------- 87 }; // namespace android 88 89
