1 /* 2 * Copyright (c) 2022-2023 Intel Corporation. 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef ZEPHYR_INCLUDE_SENSING_DATATYPES_H_ 8 #define ZEPHYR_INCLUDE_SENSING_DATATYPES_H_ 9 10 #include <stdint.h> 11 #include <zephyr/dsp/types.h> 12 13 /** 14 * @brief Data Types 15 * @addtogroup sensing_datatypes 16 * @{ 17 */ 18 19 /** 20 * @struct sensing_sensor_value_header 21 * @brief sensor value header 22 * 23 * Each sensor value data structure should have this header 24 * 25 * Here use 'base_timestamp' (uint64_t) and 'timestamp_delta' (uint32_t) to 26 * save memory usage in batching mode. 27 * 28 * The 'base_timestamp' is for readings[0], the 'timestamp_delta' is relation 29 * to the previous 'readings'. So, 30 * timestamp of readings[0] is 31 * header.base_timestamp + readings[0].timestamp_delta. 32 * timestamp of readings[1] is 33 * timestamp of readings[0] + readings[1].timestamp_delta. 34 * 35 * Since timestamp unit is micro seconds, the max 'timestamp_delta' (uint32_t) 36 * is 4295 seconds. 37 * 38 * If a sensor has batched data where two consecutive readings differ by 39 * more than 4295 seconds, the sensor subsystem core will split them 40 * across multiple instances of the readings structure, and send multiple 41 * events. 42 * 43 * This concept is borrowed from CHRE: 44 * https://cs.android.com/android/platform/superproject/+/master:\ 45 * system/chre/chre_api/include/chre_api/chre/sensor_types.h 46 */ 47 struct sensing_sensor_value_header { 48 /** Base timestamp of this data readings, unit is micro seconds */ 49 uint64_t base_timestamp; 50 /** Count of this data readings */ 51 uint16_t reading_count; 52 }; 53 54 /** 55 * @brief Sensor value data structure types based on common data types. 56 * Suitable for common sensors, such as IMU, Light sensors and orientation sensors. 57 */ 58 59 /** 60 * @brief Sensor value data structure for 3-axis sensors. 61 * struct sensing_sensor_value_3d_q31 can be used by 3D IMU sensors like: 62 * SENSING_SENSOR_TYPE_MOTION_ACCELEROMETER_3D, 63 * SENSING_SENSOR_TYPE_MOTION_UNCALIB_ACCELEROMETER_3D, 64 * SENSING_SENSOR_TYPE_MOTION_GYROMETER_3D, 65 * q31 version 66 */ 67 struct sensing_sensor_value_3d_q31 { 68 /** Header of the sensor value data structure. */ 69 struct sensing_sensor_value_header header; 70 int8_t shift; /**< The shift value for the q31_t v[3] reading. */ 71 struct { 72 /** Timestamp delta of the reading. Unit is micro seconds. */ 73 uint32_t timestamp_delta; 74 union { 75 /** 76 * 3D vector of the reading represented as an array. 77 * For SENSING_SENSOR_TYPE_MOTION_ACCELEROMETER_3D and 78 * SENSING_SENSOR_TYPE_MOTION_UNCALIB_ACCELEROMETER_3D, 79 * the unit is Gs (gravitational force). 80 * For SENSING_SENSOR_TYPE_MOTION_GYROMETER_3D, the unit is degrees. 81 */ 82 q31_t v[3]; 83 struct { 84 q31_t x; /**< X value of the 3D vector. */ 85 q31_t y; /**< Y value of the 3D vector. */ 86 q31_t z; /**< Z value of the 3D vector. */ 87 }; 88 }; 89 } readings[1]; /**< Array of readings. */ 90 }; 91 92 /** 93 * @brief Sensor value data structure for single 1-axis value. 94 * struct sensing_sensor_value_uint32 can be used by SENSING_SENSOR_TYPE_LIGHT_AMBIENTLIGHT sensor 95 * uint32_t version 96 */ 97 struct sensing_sensor_value_uint32 { 98 /** Header of the sensor value data structure. */ 99 struct sensing_sensor_value_header header; 100 struct { 101 /** Timestamp delta of the reading. Unit is micro seconds. */ 102 uint32_t timestamp_delta; 103 /** 104 * Value of the reading. 105 * For SENSING_SENSOR_TYPE_LIGHT_AMBIENTLIGHT, the unit is luxs. 106 */ 107 uint32_t v; 108 } readings[1]; /**< Array of readings. */ 109 }; 110 111 /** 112 * @brief Sensor value data structure for single 1-axis value. 113 * struct sensing_sensor_value_q31 can be used by SENSING_SENSOR_TYPE_MOTION_HINGE_ANGLE sensor 114 * q31 version 115 */ 116 struct sensing_sensor_value_q31 { 117 /** Header of the sensor value data structure. */ 118 struct sensing_sensor_value_header header; 119 int8_t shift; /**< The shift value for the q31_t v reading. */ 120 struct { 121 /** Timestamp delta of the reading. Unit is micro seconds. */ 122 uint32_t timestamp_delta; 123 /** 124 * Value of the reading. 125 * For SENSING_SENSOR_TYPE_MOTION_HINGE_ANGLE, the unit is degrees. 126 */ 127 q31_t v; 128 } readings[1]; /**< Array of readings. */ 129 }; 130 131 /** 132 * @} 133 */ 134 135 #endif /*ZEPHYR_INCLUDE_SENSING_DATATYPES_H_*/ 136
