2 * Copyright (C) 2008 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef ANDROID_SENSORS_INTERFACE_H
18 #define ANDROID_SENSORS_INTERFACE_H
21 #include <sys/cdefs.h>
22 #include <sys/types.h>
24 #include <hardware/hardware.h>
25 #include <cutils/native_handle.h>
30 * The id of this module
32 #define SENSORS_HARDWARE_MODULE_ID "sensors"
35 * Name of the sensors device to open
37 #define SENSORS_HARDWARE_CONTROL "control"
38 #define SENSORS_HARDWARE_DATA "data"
41 * Handles must be higher than SENSORS_HANDLE_BASE and must be unique.
42 * A Handle identifies a given sensors. The handle is used to activate
43 * and/or deactivate sensors.
44 * In this version of the API there can only be 256 handles.
46 #define SENSORS_HANDLE_BASE 0
47 #define SENSORS_HANDLE_BITS 8
48 #define SENSORS_HANDLE_COUNT (1<<SENSORS_HANDLE_BITS)
54 #define SENSOR_TYPE_ACCELEROMETER 1
55 #define SENSOR_TYPE_MAGNETIC_FIELD 2
56 #define SENSOR_TYPE_ORIENTATION 3
57 #define SENSOR_TYPE_GYROSCOPE 4
58 #define SENSOR_TYPE_LIGHT 5
59 #define SENSOR_TYPE_PRESSURE 6
60 #define SENSOR_TYPE_TEMPERATURE 7
61 #define SENSOR_TYPE_PROXIMITY 8
64 * Values returned by the accelerometer in various locations in the universe.
65 * all values are in SI units (m/s^2)
68 #define GRAVITY_SUN (275.0f)
69 #define GRAVITY_MERCURY (3.70f)
70 #define GRAVITY_VENUS (8.87f)
71 #define GRAVITY_EARTH (9.80665f)
72 #define GRAVITY_MOON (1.6f)
73 #define GRAVITY_MARS (3.71f)
74 #define GRAVITY_JUPITER (23.12f)
75 #define GRAVITY_SATURN (8.96f)
76 #define GRAVITY_URANUS (8.69f)
77 #define GRAVITY_NEPTUNE (11.0f)
78 #define GRAVITY_PLUTO (0.6f)
79 #define GRAVITY_DEATH_STAR_I (0.000000353036145f)
80 #define GRAVITY_THE_ISLAND (4.815162342f)
82 /** Maximum magnetic field on Earth's surface */
83 #define MAGNETIC_FIELD_EARTH_MAX (60.0f)
85 /** Minimum magnetic field on Earth's surface */
86 #define MAGNETIC_FIELD_EARTH_MIN (30.0f)
90 * status of each sensor
93 #define SENSOR_STATUS_UNRELIABLE 0
94 #define SENSOR_STATUS_ACCURACY_LOW 1
95 #define SENSOR_STATUS_ACCURACY_MEDIUM 2
96 #define SENSOR_STATUS_ACCURACY_HIGH 3
99 * Definition of the axis
100 * ----------------------
102 * This API is relative to the screen of the device in its default orientation,
103 * that is, if the device can be used in portrait or landscape, this API
104 * is only relative to the NATURAL orientation of the screen. In other words,
105 * the axis are not swapped when the device's screen orientation changes.
106 * Higher level services /may/ perform this transformation.
111 * +-----------+--> y>0
123 * |/ z>0 (toward the sky)
125 * O: Origin (x=0,y=0,z=0)
131 * All values are angles in degrees.
133 * azimuth: angle between the magnetic north direction and the Y axis, around
134 * the Z axis (0<=azimuth<360).
135 * 0=North, 90=East, 180=South, 270=West
137 * pitch: Rotation around X axis (-180<=pitch<=180), with positive values when
138 * the z-axis moves toward the y-axis.
140 * roll: Rotation around Y axis (-90<=roll<=90), with positive values when
141 * the x-axis moves AWAY from the z-axis.
143 * Note: This definition is different from yaw, pitch and roll used in aviation
144 * where the X axis is along the long side of the plane (tail to nose).
150 * All values are in SI units (m/s^2) and measure the acceleration of the
151 * device minus the force of gravity.
153 * x: Acceleration minus Gx on the x-axis
154 * y: Acceleration minus Gy on the y-axis
155 * z: Acceleration minus Gz on the z-axis
158 * When the device lies flat on a table and is pushed on its left side
159 * toward the right, the x acceleration value is positive.
161 * When the device lies flat on a table, the acceleration value is +9.81,
162 * which correspond to the acceleration of the device (0 m/s^2) minus the
163 * force of gravity (-9.81 m/s^2).
165 * When the device lies flat on a table and is pushed toward the sky, the
166 * acceleration value is greater than +9.81, which correspond to the
167 * acceleration of the device (+A m/s^2) minus the force of
168 * gravity (-9.81 m/s^2).
174 * All values are in micro-Tesla (uT) and measure the ambient magnetic
175 * field in the X, Y and Z axis.
197 * Union of the various types of sensor data
198 * that can be returned.
201 /* sensor identifier */
205 /* x,y,z values of the given sensor */
206 sensors_vec_t vector;
208 /* orientation values are in degrees */
209 sensors_vec_t orientation;
211 /* acceleration values are in meter per second per second (m/s^2) */
212 sensors_vec_t acceleration;
214 /* magnetic vector values are in micro-Tesla (uT) */
215 sensors_vec_t magnetic;
217 /* temperature is in degrees centigrade (Celsius) */
221 /* time is in nanosecond */
231 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
232 * and the fields of this data structure must begin with hw_module_t
233 * followed by module specific information.
235 struct sensors_module_t {
236 struct hw_module_t common;
239 * Enumerate all available sensors. The list is returned in "list".
240 * @return number of sensors in the list
242 int (*get_sensors_list)(struct sensors_module_t* module,
243 struct sensor_t const** list);
247 /* name of this sensors */
249 /* vendor of the hardware part */
251 /* version of the hardware part + driver. The value of this field is
252 * left to the implementation and doesn't have to be monotonicaly
256 /* handle that identifies this sensors. This handle is used to activate
257 * and deactivate this sensor. The value of the handle must be 8 bits
258 * in this version of the API.
261 /* this sensor's type. */
263 /* maximaum range of this sensor's value in SI units */
265 /* smallest difference between two values reported by this sensor */
267 /* rough estimate of this sensor's power consumption in mA */
269 /* reserved fields, must be zero */
275 * Every device data structure must begin with hw_device_t
276 * followed by module specific public methods and attributes.
278 struct sensors_control_device_t {
279 struct hw_device_t common;
282 * Returns a native_handle_t, which will be the parameter to
283 * sensors_data_device_t::open_data().
284 * The caller takes ownership of this handle. This is intended to be
285 * passed cross processes.
287 * @return a native_handle_t if successful, < 0 on error
289 native_handle_t* (*open_data_source)(struct sensors_control_device_t *dev);
291 /** Activate/deactivate one sensor.
293 * @param handle is the handle of the sensor to change.
294 * @param enabled set to 1 to enable, or 0 to disable the sensor.
296 * @return 0 on success, negative errno code otherwise
298 int (*activate)(struct sensors_control_device_t *dev,
299 int handle, int enabled);
302 * Set the delay between sensor events in ms
304 * @return 0 if successful, < 0 on error
306 int (*set_delay)(struct sensors_control_device_t *dev, int32_t ms);
309 * Causes sensors_data_device_t.poll() to return -EWOULDBLOCK immediately.
311 int (*wake)(struct sensors_control_device_t *dev);
314 struct sensors_data_device_t {
315 struct hw_device_t common;
318 * Prepare to read sensor data.
320 * This routine does NOT take ownership of the handle
321 * and must not close it. Typically this routine would
322 * use a duplicate of the nh parameter.
324 * @param nh from sensors_control_open.
326 * @return 0 if successful, < 0 on error
328 int (*data_open)(struct sensors_data_device_t *dev, native_handle_t* nh);
331 * Caller has completed using the sensor data.
332 * The caller will not be blocked in sensors_data_poll
333 * when this routine is called.
335 * @return 0 if successful, < 0 on error
337 int (*data_close)(struct sensors_data_device_t *dev);
340 * Return sensor data for one of the enabled sensors.
342 * @return sensor handle for the returned data, 0x7FFFFFFF when
343 * sensors_control_device_t.wake() is called and -errno on error
346 int (*poll)(struct sensors_data_device_t *dev,
347 sensors_data_t* data);
351 /** convenience API for opening and closing a device */
353 static inline int sensors_control_open(const struct hw_module_t* module,
354 struct sensors_control_device_t** device) {
355 return module->methods->open(module,
356 SENSORS_HARDWARE_CONTROL, (struct hw_device_t**)device);
359 static inline int sensors_control_close(struct sensors_control_device_t* device) {
360 return device->common.close(&device->common);
363 static inline int sensors_data_open(const struct hw_module_t* module,
364 struct sensors_data_device_t** device) {
365 return module->methods->open(module,
366 SENSORS_HARDWARE_DATA, (struct hw_device_t**)device);
369 static inline int sensors_data_close(struct sensors_data_device_t* device) {
370 return device->common.close(&device->common);
376 #endif // ANDROID_SENSORS_INTERFACE_H