1 /* 2 * Copyright (C) 2015 Intel Corporation 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 #ifndef SENSOR_HPP 18 #define SENSOR_HPP 19 20 /** 21 * The default sensor __attribute__((constructor)) priority is represented by 22 * the first available priority value. The [0, 100] ones are used by the system 23 * implementation. 24 */ 25 #define DEFAULT_SENSOR_CONSTRUCTOR_PRIORITY 101 26 27 #include "AcquisitionThread.hpp" 28 29 struct sensors_event_t; 30 class AcquisitionThread; 31 32 /** 33 * Sensor representation class 34 * 35 * It supports sensor enabling/disabling, changing the sensor's parameters 36 * and event reading. 37 */ 38 class Sensor { 39 public: 40 /** 41 * Sensor constructor 42 */ 43 Sensor(); 44 45 /** 46 * Sensor destructor 47 */ 48 virtual ~Sensor(); 49 50 /** 51 * Activate the sensor 52 * @param handle sensor identifier 53 * @param enabled 1 for enabling and 0 for disabling 54 * @return 0 on success and a negative error number otherwise 55 */ 56 virtual int activate(int handle, int enabled); 57 58 /** 59 * Set delay 60 * @param handle sensor identifier 61 * @param ns the sampling period at which the sensor should run, in nanoseconds 62 * @return 0 on success and a negative error number otherwise 63 */ 64 virtual int setDelay(int handle, int64_t ns); 65 66 /** 67 * Poll for events 68 * @param data where to store the events 69 * @param count the number of events returned must be <= to the count 70 * @return number of events returned in data on success and a negative error number otherwise 71 */ 72 virtual int pollEvents(sensors_event_t* data, int count) = 0; 73 74 /** 75 * Sets a sensor’s parameters, including sampling frequency and maximum report latency 76 * @param handle sensor identifier 77 * @param flags currently unused 78 * @param period_ns the sampling period at which the sensor should run, in nanoseconds 79 * @param timeout the maximum time by which events can be delayed before being reported 80 * through the HAL, in nanoseconds 81 * @return 0 on success and a negative error number otherwise 82 */ 83 virtual int batch(int handle, int flags, int64_t period_ns, int64_t timeout); 84 85 /** 86 * Add a flush complete event to the end of the hardware FIFO for the specified sensor and flushes the FIFO 87 * @param handle sensor identifier 88 * @return 0 on success and a negative error number otherwise 89 */ 90 virtual int flush(int handle); 91 92 /** 93 * Read and store an event 94 * @param event where to store the event 95 * @return true on success and a false otherwise 96 */ 97 virtual bool readOneEvent(sensors_event_t *event); 98 99 /** 100 * Get sensor identifier 101 * @return sensor handle 102 */ getHandle()103 int getHandle() { return handle; } 104 105 /** 106 * Get sensor type 107 * @return sensor type 108 */ getType()109 int getType() { return type; } 110 111 /** 112 * Get sensor delay in nanoseconds 113 * @return sensor delay 114 */ getDelay()115 int64_t getDelay() { return delay; } 116 117 /** 118 * Gravitational acceleration constant in m/s^2 119 */ 120 static const float kGravitationalAcceleration; 121 122 protected: 123 /** 124 * Enable or disable the associated acquisition thread 125 * @param pollFd poll file descriptor 126 * @param handle sensor identifier 127 * @param enabled 1 for enabling and 0 for disabling 128 * @return 0 on success and a negative error number otherwise 129 */ 130 virtual int activateAcquisitionThread(int pollFd, int handle, int enabled); 131 132 AcquisitionThread *acquisitionThread; 133 int handle, type; 134 int64_t delay; 135 }; 136 137 #endif // SENSOR_HPP 138