1 /* 2 * Copyright (C) 2022 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 #ifndef ANDROID_HARDWARE_CONTEXTHUB_COMMON_CHRE_CONNECTION_H_ 17 #define ANDROID_HARDWARE_CONTEXTHUB_COMMON_CHRE_CONNECTION_H_ 18 19 #include <flatbuffers/flatbuffers.h> 20 #include <chrono> 21 #include <cstddef> 22 #include <cstdint> 23 #include <future> 24 #include <string> 25 #include "chre_host/fragmented_load_transaction.h" 26 #include "hal_client_id.h" 27 28 namespace android::hardware::contexthub::common::implementation { 29 30 /** This abstract class defines the interface between HAL and CHRE. */ 31 class ChreConnection { 32 public: 33 virtual ~ChreConnection() = default; 34 35 /** 36 * Initializes the connection between HAL and CHRE. 37 * 38 * @return true if success, otherwise false. 39 */ 40 virtual bool init() = 0; 41 42 /** 43 * Sends a message to CHRE. 44 * 45 * @return true if success, otherwise false. 46 */ 47 virtual bool sendMessage(void *data, size_t length) = 0; 48 49 /** 50 * @return The nanoapp loading fragment size in bytes. 51 */ getLoadFragmentSizeBytes()52 virtual size_t getLoadFragmentSizeBytes() const { 53 static_assert(CHRE_HOST_DEFAULT_FRAGMENT_SIZE > 0); 54 return CHRE_HOST_DEFAULT_FRAGMENT_SIZE; 55 } 56 57 /** 58 * Sends a message encapsulated in a FlatBufferBuilder to CHRE. 59 * 60 * @return true if success, otherwise false. 61 */ sendMessage(const flatbuffers::FlatBufferBuilder & builder)62 inline bool sendMessage(const flatbuffers::FlatBufferBuilder &builder) { 63 return sendMessage(builder.GetBufferPointer(), builder.GetSize()); 64 } 65 66 /** 67 * Gets the offset between the Context hub and Android time in nanoseconds. 68 * 69 * This function may be used for synchronizing timestamps between the Context 70 * hub and Android. 71 * 72 * @param offset points to the address storing the offset in nanoseconds which 73 * is defined as android time - context hub time. 74 * @return true on success, otherwise false. 75 */ getTimeOffset(int64_t *)76 virtual bool getTimeOffset(int64_t * /*offset*/) { 77 return false; 78 } 79 80 /** 81 * Returns true if time sync is required by the platform, false otherwise. 82 * 83 * When this function returns false, getTimeOffset may not be implemented. 84 */ isTimeSyncNeeded()85 virtual bool isTimeSyncNeeded() { 86 return false; 87 } 88 89 /** 90 * Returns debug information. 91 */ dump()92 virtual std::string dump() { 93 return {}; 94 } 95 }; 96 97 } // namespace android::hardware::contexthub::common::implementation 98 #endif // ANDROID_HARDWARE_CONTEXTHUB_COMMON_CHRE_CONNECTION_H_ 99