1 /* 2 * Copyright (C) 2008-2014 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 #ifndef ANDROID_SENSOR_BASE_H 18 #define ANDROID_SENSOR_BASE_H 19 20 #include <errno.h> 21 #include <stdint.h> 22 #include <sys/cdefs.h> 23 #include <sys/types.h> 24 25 26 /*****************************************************************************/ 27 28 struct sensors_event_t; 29 30 #define NS_PER_SEC 1000000000LL 31 #define NS_PER_US 1000 32 33 class SensorBase { 34 protected: 35 const char* dev_name; 36 const char* data_name; 37 int dev_fd; 38 int data_fd; 39 40 static int64_t getTimestamp(); 41 42 timevalToNano(timeval const & t)43 static int64_t timevalToNano(timeval const& t) { 44 return t.tv_sec*NS_PER_SEC + t.tv_usec*NS_PER_US; 45 } 46 47 int open_device(); 48 int close_device(); 49 int write_int(char const *path, int value); 50 int write_sys_attribute( 51 char const *path, char const *value, int bytes); 52 53 public: 54 SensorBase( 55 const char* dev_name, 56 const char* data_name); 57 58 virtual ~SensorBase(); 59 60 virtual int readEvents(sensors_event_t* data, int count) = 0; 61 virtual bool hasPendingEvents() const; 62 virtual int getFd() const; getPollTime()63 virtual int getPollTime() { return -1; } 64 virtual int setDelay(int32_t handle, int64_t ns); 65 virtual int64_t getDelay(int32_t handle); 66 67 // When this function is called, increments the reference counter. 68 virtual int setEnable(int32_t handle, int enabled) = 0; 69 // It returns the number of reference. 70 virtual int getEnable(int32_t handle) = 0; 71 virtual int batch(int handle, int flags, int64_t period_ns, int64_t timeout) = 0; 72 virtual int flush(int handle) = 0; 73 }; 74 75 /*****************************************************************************/ 76 77 #endif // ANDROID_SENSOR_BASE_H 78