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/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_SENSORS_INTERFACE_H
#define ANDROID_SENSORS_INTERFACE_H
#include <stdint.h>
#include <sys/cdefs.h>
#include <sys/types.h>
#include <hardware/hardware.h>
#include <cutils/native_handle.h>
__BEGIN_DECLS
/**
* The id of this module
*/
#define SENSORS_HARDWARE_MODULE_ID "sensors"
/**
* Name of the sensors device to open
*/
#define SENSORS_HARDWARE_POLL "poll"
/**
* Handles must be higher than SENSORS_HANDLE_BASE and must be unique.
* A Handle identifies a given sensors. The handle is used to activate
* and/or deactivate sensors.
* In this version of the API there can only be 256 handles.
*/
#define SENSORS_HANDLE_BASE 0
#define SENSORS_HANDLE_BITS 8
#define SENSORS_HANDLE_COUNT (1<<SENSORS_HANDLE_BITS)
/**
* Sensor types
*/
#define SENSOR_TYPE_ACCELEROMETER 1
#define SENSOR_TYPE_MAGNETIC_FIELD 2
#define SENSOR_TYPE_ORIENTATION 3
#define SENSOR_TYPE_GYROSCOPE 4
#define SENSOR_TYPE_LIGHT 5
#define SENSOR_TYPE_PRESSURE 6
#define SENSOR_TYPE_TEMPERATURE 7
#define SENSOR_TYPE_PROXIMITY 8
/**
* Values returned by the accelerometer in various locations in the universe.
* all values are in SI units (m/s^2)
*/
#define GRAVITY_SUN (275.0f)
#define GRAVITY_EARTH (9.80665f)
/** Maximum magnetic field on Earth's surface */
#define MAGNETIC_FIELD_EARTH_MAX (60.0f)
/** Minimum magnetic field on Earth's surface */
#define MAGNETIC_FIELD_EARTH_MIN (30.0f)
/**
* status of each sensor
*/
#define SENSOR_STATUS_UNRELIABLE 0
#define SENSOR_STATUS_ACCURACY_LOW 1
#define SENSOR_STATUS_ACCURACY_MEDIUM 2
#define SENSOR_STATUS_ACCURACY_HIGH 3
/**
* Definition of the axis
* ----------------------
*
* This API is relative to the screen of the device in its default orientation,
* that is, if the device can be used in portrait or landscape, this API
* is only relative to the NATURAL orientation of the screen. In other words,
* the axis are not swapped when the device's screen orientation changes.
* Higher level services /may/ perform this transformation.
*
* x<0 x>0
* ^
* |
* +-----------+--> y>0
* | |
* | |
* | |
* | | / z<0
* | | /
* | | /
* O-----------+/
* |[] [ ] []/
* +----------/+ y<0
* /
* /
* |/ z>0 (toward the sky)
*
* O: Origin (x=0,y=0,z=0)
*
*
* Orientation
* -----------
*
* All values are angles in degrees.
*
* Orientation sensors return sensor events for all 3 axes at a constant
* rate defined by setDelay().
*
* azimuth: angle between the magnetic north direction and the Y axis, around
* the Z axis (0<=azimuth<360).
* 0=North, 90=East, 180=South, 270=West
*
* pitch: Rotation around X axis (-180<=pitch<=180), with positive values when
* the z-axis moves toward the y-axis.
*
* roll: Rotation around Y axis (-90<=roll<=90), with positive values when
* the x-axis moves towards the z-axis.
*
* Note: For historical reasons the roll angle is positive in the clockwise
* direction (mathematically speaking, it should be positive in the
* counter-clockwise direction):
*
* Z
* ^
* (+roll) .--> |
* / |
* | | roll: rotation around Y axis
* X <-------(.)
* Y
* note that +Y == -roll
*
*
*
* Note: This definition is different from yaw, pitch and roll used in aviation
* where the X axis is along the long side of the plane (tail to nose).
*
*
* Acceleration
* ------------
*
* All values are in SI units (m/s^2) and measure the acceleration of the
* device minus the force of gravity.
*
* Acceleration sensors return sensor events for all 3 axes at a constant
* rate defined by setDelay().
*
* x: Acceleration minus Gx on the x-axis
* y: Acceleration minus Gy on the y-axis
* z: Acceleration minus Gz on the z-axis
*
* Examples:
* When the device lies flat on a table and is pushed on its left side
* toward the right, the x acceleration value is positive.
*
* When the device lies flat on a table, the acceleration value is +9.81,
* which correspond to the acceleration of the device (0 m/s^2) minus the
* force of gravity (-9.81 m/s^2).
*
* When the device lies flat on a table and is pushed toward the sky, the
* acceleration value is greater than +9.81, which correspond to the
* acceleration of the device (+A m/s^2) minus the force of
* gravity (-9.81 m/s^2).
*
*
* Magnetic Field
* --------------
*
* All values are in micro-Tesla (uT) and measure the ambient magnetic
* field in the X, Y and Z axis.
*
* Magnetic Field sensors return sensor events for all 3 axes at a constant
* rate defined by setDelay().
*
* Proximity
* ---------
*
* The distance value is measured in centimeters. Note that some proximity
* sensors only support a binary "close" or "far" measurement. In this case,
* the sensor should report its maxRange value in the "far" state and a value
* less than maxRange in the "near" state.
*
* Proximity sensors report a value only when it changes. setDelay() is
* ignored.
*
* Light
* -----
*
* The light sensor value is returned in SI lux units.
*
* Light sensors report a value only when it changes. setDelay() is
* ignored.
*
*/
typedef struct {
union {
float v[3];
struct {
float x;
float y;
float z;
};
struct {
float azimuth;
float pitch;
float roll;
};
};
int8_t status;
uint8_t reserved[3];
} sensors_vec_t;
/**
* Union of the various types of sensor data
* that can be returned.
*/
typedef struct sensors_event_t {
/* must be sizeof(struct sensors_event_t) */
int32_t version;
/* sensor identifier */
int32_t sensor;
/* sensor type */
int32_t type;
/* reserved */
int32_t reserved0;
/* time is in nanosecond */
int64_t timestamp;
union {
float data[16];
/* acceleration values are in meter per second per second (m/s^2) */
sensors_vec_t acceleration;
/* magnetic vector values are in micro-Tesla (uT) */
sensors_vec_t magnetic;
/* orientation values are in degrees */
sensors_vec_t orientation;
/* temperature is in degrees centigrade (Celsius) */
float temperature;
/* distance in centimeters */
float distance;
/* light in SI lux units */
float light;
};
uint32_t reserved1[4];
} sensors_event_t;
struct sensor_t;
/**
* Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
* and the fields of this data structure must begin with hw_module_t
* followed by module specific information.
*/
struct sensors_module_t {
struct hw_module_t common;
/**
* Enumerate all available sensors. The list is returned in "list".
* @return number of sensors in the list
*/
int (*get_sensors_list)(struct sensors_module_t* module,
struct sensor_t const** list);
};
struct sensor_t {
/* name of this sensors */
const char* name;
/* vendor of the hardware part */
const char* vendor;
/* version of the hardware part + driver. The value of this field is
* left to the implementation and doesn't have to be monotonically
* increasing.
*/
int version;
/* handle that identifies this sensors. This handle is used to activate
* and deactivate this sensor. The value of the handle must be 8 bits
* in this version of the API.
*/
int handle;
/* this sensor's type. */
int type;
/* maximaum range of this sensor's value in SI units */
float maxRange;
/* smallest difference between two values reported by this sensor */
float resolution;
/* rough estimate of this sensor's power consumption in mA */
float power;
/* reserved fields, must be zero */
void* reserved[9];
};
/**
* Every device data structure must begin with hw_device_t
* followed by module specific public methods and attributes.
*/
struct sensors_poll_device_t {
struct hw_device_t common;
/** Activate/deactivate one sensor.
*
* @param handle is the handle of the sensor to change.
* @param enabled set to 1 to enable, or 0 to disable the sensor.
*
* @return 0 on success, negative errno code otherwise
*/
int (*activate)(struct sensors_poll_device_t *dev,
int handle, int enabled);
/**
* Set the delay between sensor events in nanoseconds for a given sensor
*
* @return 0 if successful, < 0 on error
*/
int (*setDelay)(struct sensors_poll_device_t *dev,
int handle, int64_t ns);
/**
* Returns an array of sensor data.
*
* @return the number of events read on success, or -errno in case of an error.
*
*/
int (*poll)(struct sensors_poll_device_t *dev,
sensors_event_t* data, int count);
};
/** convenience API for opening and closing a device */
static inline int sensors_open(const struct hw_module_t* module,
struct sensors_poll_device_t** device) {
return module->methods->open(module,
SENSORS_HARDWARE_POLL, (struct hw_device_t**)device);
}
static inline int sensors_close(struct sensors_poll_device_t* device) {
return device->common.close(&device->common);
}
__END_DECLS
#include <hardware/sensors_deprecated.h>
#endif // ANDROID_SENSORS_INTERFACE_H