move TARGET_SPECIFIC_HEADER_PATH from smdk4412-common to here

1 files changed, 949 insertions, 0 deletions

diff --git a/include/hardware/gps.h b/include/hardware/gps.h
new file mode 100644
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--- /dev/null
+++ b/include/hardware/gps.h
@@ -0,0 +1,949 @@
+/*
+ * Copyright (C) 2010 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_INCLUDE_HARDWARE_GPS_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_H
+
+#include <stdint.h>
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <pthread.h>
+
+#include <hardware/hardware.h>
+
+__BEGIN_DECLS
+
+/**
+ * The id of this module
+ */
+#define GPS_HARDWARE_MODULE_ID "gps"
+
+
+/** Milliseconds since January 1, 1970 */
+typedef int64_t GpsUtcTime;
+
+/** Maximum number of SVs for gps_sv_status_callback(). */
+#define GPS_MAX_SVS 32
+
+/** Requested operational mode for GPS operation. */
+typedef uint32_t GpsPositionMode;
+// IMPORTANT: Note that the following values must match
+// constants in GpsLocationProvider.java.
+/** Mode for running GPS standalone (no assistance). */
+#define GPS_POSITION_MODE_STANDALONE    0
+/** AGPS MS-Based mode. */
+#define GPS_POSITION_MODE_MS_BASED      1
+/** AGPS MS-Assisted mode. */
+#define GPS_POSITION_MODE_MS_ASSISTED   2
+
+/** Requested recurrence mode for GPS operation. */
+typedef uint32_t GpsPositionRecurrence;
+// IMPORTANT: Note that the following values must match
+// constants in GpsLocationProvider.java.
+/** Receive GPS fixes on a recurring basis at a specified period. */
+#define GPS_POSITION_RECURRENCE_PERIODIC    0
+/** Request a single shot GPS fix. */
+#define GPS_POSITION_RECURRENCE_SINGLE      1
+
+/** GPS status event values. */
+typedef uint16_t GpsStatusValue;
+// IMPORTANT: Note that the following values must match
+// constants in GpsLocationProvider.java.
+/** GPS status unknown. */
+#define GPS_STATUS_NONE             0
+/** GPS has begun navigating. */
+#define GPS_STATUS_SESSION_BEGIN    1
+/** GPS has stopped navigating. */
+#define GPS_STATUS_SESSION_END      2
+/** GPS has powered on but is not navigating. */
+#define GPS_STATUS_ENGINE_ON        3
+/** GPS is powered off. */
+#define GPS_STATUS_ENGINE_OFF       4
+
+/** Flags to indicate which values are valid in a GpsLocation. */
+typedef uint16_t GpsLocationFlags;
+// IMPORTANT: Note that the following values must match
+// constants in GpsLocationProvider.java.
+/** GpsLocation has valid latitude and longitude. */
+#define GPS_LOCATION_HAS_LAT_LONG   0x0001
+/** GpsLocation has valid altitude. */
+#define GPS_LOCATION_HAS_ALTITUDE   0x0002
+/** GpsLocation has valid speed. */
+#define GPS_LOCATION_HAS_SPEED      0x0004
+/** GpsLocation has valid bearing. */
+#define GPS_LOCATION_HAS_BEARING    0x0008
+/** GpsLocation has valid accuracy. */
+#define GPS_LOCATION_HAS_ACCURACY   0x0010
+
+/** Flags for the gps_set_capabilities callback. */
+
+/** GPS HAL schedules fixes for GPS_POSITION_RECURRENCE_PERIODIC mode.
+    If this is not set, then the framework will use 1000ms for min_interval
+    and will start and call start() and stop() to schedule the GPS.
+ */
+#define GPS_CAPABILITY_SCHEDULING       0x0000001
+/** GPS supports MS-Based AGPS mode */
+#define GPS_CAPABILITY_MSB              0x0000002
+/** GPS supports MS-Assisted AGPS mode */
+#define GPS_CAPABILITY_MSA              0x0000004
+/** GPS supports single-shot fixes */
+#define GPS_CAPABILITY_SINGLE_SHOT      0x0000008
+/** GPS supports on demand time injection */
+#define GPS_CAPABILITY_ON_DEMAND_TIME   0x0000010
+
+/** Flags used to specify which aiding data to delete
+    when calling delete_aiding_data(). */
+typedef uint16_t GpsAidingData;
+// IMPORTANT: Note that the following values must match
+// constants in GpsLocationProvider.java.
+#define GPS_DELETE_EPHEMERIS        0x0001
+#define GPS_DELETE_ALMANAC          0x0002
+#define GPS_DELETE_POSITION         0x0004
+#define GPS_DELETE_TIME             0x0008
+#define GPS_DELETE_IONO             0x0010
+#define GPS_DELETE_UTC              0x0020
+#define GPS_DELETE_HEALTH           0x0040
+#define GPS_DELETE_SVDIR            0x0080
+#define GPS_DELETE_SVSTEER          0x0100
+#define GPS_DELETE_SADATA           0x0200
+#define GPS_DELETE_RTI              0x0400
+#define GPS_DELETE_CELLDB_INFO      0x8000
+#define GPS_DELETE_ALL              0xFFFF
+
+/** AGPS type */
+typedef uint16_t AGpsType;
+#define AGPS_TYPE_SUPL          1
+#define AGPS_TYPE_C2K           2
+
+typedef uint16_t AGpsSetIDType;
+#define AGPS_SETID_TYPE_NONE    0
+#define AGPS_SETID_TYPE_IMSI    1
+#define AGPS_SETID_TYPE_MSISDN  2
+
+/**
+ * String length constants
+ */
+#define GPS_NI_SHORT_STRING_MAXLEN      256
+#define GPS_NI_LONG_STRING_MAXLEN       2048
+
+/**
+ * GpsNiType constants
+ */
+typedef uint32_t GpsNiType;
+#define GPS_NI_TYPE_VOICE              1
+#define GPS_NI_TYPE_UMTS_SUPL          2
+#define GPS_NI_TYPE_UMTS_CTRL_PLANE    3
+
+/**
+ * GpsNiNotifyFlags constants
+ */
+typedef uint32_t GpsNiNotifyFlags;
+/** NI requires notification */
+#define GPS_NI_NEED_NOTIFY          0x0001
+/** NI requires verification */
+#define GPS_NI_NEED_VERIFY          0x0002
+/** NI requires privacy override, no notification/minimal trace */
+#define GPS_NI_PRIVACY_OVERRIDE     0x0004
+
+/**
+ * GPS NI responses, used to define the response in
+ * NI structures
+ */
+typedef int GpsUserResponseType;
+#define GPS_NI_RESPONSE_ACCEPT         1
+#define GPS_NI_RESPONSE_DENY           2
+#define GPS_NI_RESPONSE_NORESP         3
+
+/**
+ * NI data encoding scheme
+ */
+typedef int GpsNiEncodingType;
+#define GPS_ENC_NONE                   0
+#define GPS_ENC_SUPL_GSM_DEFAULT       1
+#define GPS_ENC_SUPL_UTF8              2
+#define GPS_ENC_SUPL_UCS2              3
+#define GPS_ENC_UNKNOWN                -1
+
+/** AGPS status event values. */
+typedef uint16_t AGpsStatusValue;
+/** GPS requests data connection for AGPS. */
+#define GPS_REQUEST_AGPS_DATA_CONN  1
+/** GPS releases the AGPS data connection. */
+#define GPS_RELEASE_AGPS_DATA_CONN  2
+/** AGPS data connection initiated */
+#define GPS_AGPS_DATA_CONNECTED     3
+/** AGPS data connection completed */
+#define GPS_AGPS_DATA_CONN_DONE     4
+/** AGPS data connection failed */
+#define GPS_AGPS_DATA_CONN_FAILED   5
+
+#define AGPS_REF_LOCATION_TYPE_GSM_CELLID   1
+#define AGPS_REF_LOCATION_TYPE_UMTS_CELLID  2
+#define AGPS_REG_LOCATION_TYPE_MAC          3
+
+/** Network types for update_network_state "type" parameter */
+#define AGPS_RIL_NETWORK_TYPE_MOBILE        0
+#define AGPS_RIL_NETWORK_TYPE_WIFI          1
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_MMS    2
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_SUPL   3
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_DUN   4
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_HIPRI 5
+#define AGPS_RIL_NETWORK_TTYPE_WIMAX        6
+
+/**
+ * Name for the GPS XTRA interface.
+ */
+#define GPS_XTRA_INTERFACE      "gps-xtra"
+
+/**
+ * Name for the GPS DEBUG interface.
+ */
+#define GPS_DEBUG_INTERFACE      "gps-debug"
+
+/**
+ * Name for the AGPS interface.
+ */
+#define AGPS_INTERFACE      "agps"
+
+/**
+ * Name for NI interface
+ */
+#define GPS_NI_INTERFACE "gps-ni"
+
+/**
+ * Name for the AGPS-RIL interface.
+ */
+#define AGPS_RIL_INTERFACE      "agps_ril"
+
+/**
+ * The GPS chipset can use Psc for AGPS.
+ */
+#define AGPS_USE_PSC
+
+/*
+ * Name for the GPS_Geofencing interface.
+ */
+#define GPS_GEOFENCING_INTERFACE   "gps_geofencing"
+
+/** Represents a location. */
+typedef struct {
+    /** set to sizeof(GpsLocation) */
+    size_t          size;
+    /** Contains GpsLocationFlags bits. */
+    uint16_t        flags;
+    /** Represents latitude in degrees. */
+    double          latitude;
+    /** Represents longitude in degrees. */
+    double          longitude;
+    /** Represents altitude in meters above the WGS 84 reference
+     * ellipsoid. */
+    double          altitude;
+    /** Represents speed in meters per second. */
+    float           speed;
+    /** Represents heading in degrees. */
+    float           bearing;
+    /** Represents expected accuracy in meters. */
+    float           accuracy;
+    /** Timestamp for the location fix. */
+    GpsUtcTime      timestamp;
+} GpsLocation;
+
+/** Represents the status. */
+typedef struct {
+    /** set to sizeof(GpsStatus) */
+    size_t          size;
+    GpsStatusValue status;
+} GpsStatus;
+
+/** Represents SV information. */
+typedef struct {
+    /** set to sizeof(GpsSvInfo) */
+    size_t          size;
+    /** Pseudo-random number for the SV. */
+    int     prn;
+    /** Signal to noise ratio. */
+    float   snr;
+    /** Elevation of SV in degrees. */
+    float   elevation;
+    /** Azimuth of SV in degrees. */
+    float   azimuth;
+    /** Unknown field in Samsung I9100 libgps
+        May be an indicator for constellation type
+        (GPS, GLONASS, Galileo)?
+        Used on GT-I9100, likely also present on GT-N7000,
+        SGH-I717, SGH-I727 but this needs confirmation.
+    */
+    int unknown_samsung_field;
+} GpsSvInfo;
+
+/** Represents SV status. */
+typedef struct {
+    /** set to sizeof(GpsSvStatus) */
+    size_t          size;
+
+    /** Number of SVs currently visible. */
+    int         num_svs;
+
+    /** Contains an array of SV information. */
+    GpsSvInfo   sv_list[GPS_MAX_SVS];
+
+    /** Represents a bit mask indicating which SVs
+     * have ephemeris data.
+     */
+    uint32_t    ephemeris_mask;
+
+    /** Represents a bit mask indicating which SVs
+     * have almanac data.
+     */
+    uint32_t    almanac_mask;
+
+    /**
+     * Represents a bit mask indicating which SVs
+     * were used for computing the most recent position fix.
+     */
+    uint32_t    used_in_fix_mask;
+} GpsSvStatus;
+
+/* 2G and 3G */
+/* In 3G lac is discarded */
+typedef struct {
+    uint16_t type;
+    uint16_t mcc;
+    uint16_t mnc;
+    uint16_t lac;
+#ifdef AGPS_USE_PSC
+    uint16_t psc;
+#endif
+    uint32_t cid;
+} AGpsRefLocationCellID;
+
+typedef struct {
+    uint8_t mac[6];
+} AGpsRefLocationMac;
+
+/** Represents ref locations */
+typedef struct {
+    uint16_t type;
+    union {
+        AGpsRefLocationCellID   cellID;
+        AGpsRefLocationMac      mac;
+    } u;
+} AGpsRefLocation;
+
+/** Callback with location information.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_location_callback)(GpsLocation* location);
+
+/** Callback with status information.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_status_callback)(GpsStatus* status);
+
+/** Callback with SV status information.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_sv_status_callback)(GpsSvStatus* sv_info);
+
+/** Callback for reporting NMEA sentences.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_nmea_callback)(GpsUtcTime timestamp, const char* nmea, int length);
+
+/** Callback to inform framework of the GPS engine's capabilities.
+ *  Capability parameter is a bit field of GPS_CAPABILITY_* flags.
+ */
+typedef void (* gps_set_capabilities)(uint32_t capabilities);
+
+/** Callback utility for acquiring the GPS wakelock.
+ *  This can be used to prevent the CPU from suspending while handling GPS events.
+ */
+typedef void (* gps_acquire_wakelock)();
+
+/** Callback utility for releasing the GPS wakelock. */
+typedef void (* gps_release_wakelock)();
+
+/** Callback for requesting NTP time */
+typedef void (* gps_request_utc_time)();
+
+/** Callback for creating a thread that can call into the Java framework code.
+ *  This must be used to create any threads that report events up to the framework.
+ */
+typedef pthread_t (* gps_create_thread)(const char* name, void (*start)(void *), void* arg);
+
+/** GPS callback structure. */
+typedef struct {
+    /** set to sizeof(GpsCallbacks) */
+    size_t      size;
+    gps_location_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+} GpsCallbacks;
+
+
+/** Represents the standard GPS interface. */
+typedef struct {
+    /** set to sizeof(GpsInterface) */
+    size_t          size;
+    /**
+     * Opens the interface and provides the callback routines
+     * to the implemenation of this interface.
+     */
+    int   (*init)( GpsCallbacks* callbacks );
+
+    /** Starts navigating. */
+    int   (*start)( void );
+
+    /** Stops navigating. */
+    int   (*stop)( void );
+
+    /** Closes the interface. */
+    void  (*cleanup)( void );
+
+    /** Injects the current time. */
+    int   (*inject_time)(GpsUtcTime time, int64_t timeReference,
+                         int uncertainty);
+
+    /** Injects current location from another location provider
+     *  (typically cell ID).
+     *  latitude and longitude are measured in degrees
+     *  expected accuracy is measured in meters
+     */
+    int  (*inject_location)(double latitude, double longitude, float accuracy);
+
+    /**
+     * Specifies that the next call to start will not use the
+     * information defined in the flags. GPS_DELETE_ALL is passed for
+     * a cold start.
+     */
+    void  (*delete_aiding_data)(GpsAidingData flags);
+
+    /**
+     * min_interval represents the time between fixes in milliseconds.
+     * preferred_accuracy represents the requested fix accuracy in meters.
+     * preferred_time represents the requested time to first fix in milliseconds.
+     */
+    int   (*set_position_mode)(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time);
+
+    /** Get a pointer to extension information. */
+    const void* (*get_extension)(const char* name);
+} GpsInterface;
+
+/** Callback to request the client to download XTRA data.
+ *  The client should download XTRA data and inject it by calling inject_xtra_data().
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_xtra_download_request)();
+
+/** Callback structure for the XTRA interface. */
+typedef struct {
+    gps_xtra_download_request download_request_cb;
+    gps_create_thread create_thread_cb;
+} GpsXtraCallbacks;
+
+/** Extended interface for XTRA support. */
+typedef struct {
+    /** set to sizeof(GpsXtraInterface) */
+    size_t          size;
+    /**
+     * Opens the XTRA interface and provides the callback routines
+     * to the implemenation of this interface.
+     */
+    int  (*init)( GpsXtraCallbacks* callbacks );
+    /** Injects XTRA data into the GPS. */
+    int  (*inject_xtra_data)( char* data, int length );
+} GpsXtraInterface;
+
+/** Extended interface for DEBUG support. */
+typedef struct {
+    /** set to sizeof(GpsDebugInterface) */
+    size_t          size;
+
+    /**
+     * This function should return any information that the native
+     * implementation wishes to include in a bugreport.
+     */
+    size_t (*get_internal_state)(char* buffer, size_t bufferSize);
+} GpsDebugInterface;
+
+/** Represents the status of AGPS. */
+typedef struct {
+    /** set to sizeof(AGpsStatus) */
+    size_t          size;
+
+    AGpsType        type;
+    AGpsStatusValue status;
+    uint32_t        ipaddr;
+} AGpsStatus;
+
+/** Callback with AGPS status information.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* agps_status_callback)(AGpsStatus* status);
+
+/** Callback structure for the AGPS interface. */
+typedef struct {
+    agps_status_callback status_cb;
+    gps_create_thread create_thread_cb;
+} AGpsCallbacks;
+
+
+/** Extended interface for AGPS support. */
+typedef struct {
+    /** set to sizeof(AGpsInterface) */
+    size_t          size;
+
+    /**
+     * Opens the AGPS interface and provides the callback routines
+     * to the implemenation of this interface.
+     */
+    void  (*init)( AGpsCallbacks* callbacks );
+    /**
+     * Notifies that a data connection is available and sets 
+     * the name of the APN to be used for SUPL.
+     */
+    int  (*data_conn_open)( const char* apn );
+    /**
+     * Notifies that the AGPS data connection has been closed.
+     */
+    int  (*data_conn_closed)();
+    /**
+     * Notifies that a data connection is not available for AGPS. 
+     */
+    int  (*data_conn_failed)();
+    /**
+     * Sets the hostname and port for the AGPS server.
+     */
+    int  (*set_server)( AGpsType type, const char* hostname, int port );
+} AGpsInterface;
+
+
+/** Represents an NI request */
+typedef struct {
+    /** set to sizeof(GpsNiNotification) */
+    size_t          size;
+
+    /**
+     * An ID generated by HAL to associate NI notifications and UI
+     * responses
+     */
+    int             notification_id;
+
+    /**
+     * An NI type used to distinguish different categories of NI
+     * events, such as GPS_NI_TYPE_VOICE, GPS_NI_TYPE_UMTS_SUPL, ...
+     */
+    GpsNiType       ni_type;
+
+    /**
+     * Notification/verification options, combinations of GpsNiNotifyFlags constants
+     */
+    GpsNiNotifyFlags notify_flags;
+
+    /**
+     * Timeout period to wait for user response.
+     * Set to 0 for no time out limit.
+     */
+    int             timeout;
+
+    /**
+     * Default response when time out.
+     */
+    GpsUserResponseType default_response;
+
+    /**
+     * Requestor ID
+     */
+    char            requestor_id[GPS_NI_SHORT_STRING_MAXLEN];
+
+    /**
+     * Notification message. It can also be used to store client_id in some cases
+     */
+    char            text[GPS_NI_LONG_STRING_MAXLEN];
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType requestor_id_encoding;
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType text_encoding;
+
+    /**
+     * A pointer to extra data. Format:
+     * key_1 = value_1
+     * key_2 = value_2
+     */
+    char           extras[GPS_NI_LONG_STRING_MAXLEN];
+
+} GpsNiNotification;
+
+/** Callback with NI notification.
+ *  Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (*gps_ni_notify_callback)(GpsNiNotification *notification);
+
+/** GPS NI callback structure. */
+typedef struct
+{
+    /**
+     * Sends the notification request from HAL to GPSLocationProvider.
+     */
+    gps_ni_notify_callback notify_cb;
+    gps_create_thread create_thread_cb;
+} GpsNiCallbacks;
+
+/**
+ * Extended interface for Network-initiated (NI) support.
+ */
+typedef struct
+{
+    /** set to sizeof(GpsNiInterface) */
+    size_t          size;
+
+   /** Registers the callbacks for HAL to use. */
+   void (*init) (GpsNiCallbacks *callbacks);
+
+   /** Sends a response to HAL. */
+   void (*respond) (int notif_id, GpsUserResponseType user_response);
+} GpsNiInterface;
+
+struct gps_device_t {
+    struct hw_device_t common;
+
+    /**
+     * Set the provided lights to the provided values.
+     *
+     * Returns: 0 on succes, error code on failure.
+     */
+    const GpsInterface* (*get_gps_interface)(struct gps_device_t* dev);
+};
+
+#define AGPS_RIL_REQUEST_SETID_IMSI     (1<<0L)
+#define AGPS_RIL_REQUEST_SETID_MSISDN   (1<<1L)
+
+#define AGPS_RIL_REQUEST_REFLOC_CELLID  (1<<0L)
+#define AGPS_RIL_REQUEST_REFLOC_MAC     (1<<1L)
+
+typedef void (*agps_ril_request_set_id)(uint32_t flags);
+typedef void (*agps_ril_request_ref_loc)(uint32_t flags);
+
+typedef struct {
+    agps_ril_request_set_id request_setid;
+    agps_ril_request_ref_loc request_refloc;
+    gps_create_thread create_thread_cb;
+} AGpsRilCallbacks;
+
+/** Extended interface for AGPS_RIL support. */
+typedef struct {
+    /** set to sizeof(AGpsRilInterface) */
+    size_t          size;
+    /**
+     * Opens the AGPS interface and provides the callback routines
+     * to the implemenation of this interface.
+     */
+    void  (*init)( AGpsRilCallbacks* callbacks );
+
+    /**
+     * Sets the reference location.
+     */
+    void (*set_ref_location) (const AGpsRefLocation *agps_reflocation, size_t sz_struct);
+    /**
+     * Sets the set ID.
+     */
+    void (*set_set_id) (AGpsSetIDType type, const char* setid);
+
+    /**
+     * Send network initiated message.
+     */
+    void (*ni_message) (uint8_t *msg, size_t len);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_state) (int connected, int type, int roaming, const char* extra_info);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_availability) (int avaiable, const char* apn);
+} AGpsRilInterface;
+/**
+ * GPS Geofence.
+ *      There are 3 states associated with a Geofence: Inside, Outside, Unknown.
+ * There are 3 transitions: ENTERED, EXITED, UNCERTAIN.
+ *
+ * An example state diagram with confidence level: 95% and Unknown time limit
+ * set as 30 secs is shown below. (confidence level and Unknown time limit are
+ * explained latter)
+ *                         ____________________________
+ *                        |       Unknown (30 secs)   |
+ *                         """"""""""""""""""""""""""""
+ *                            ^ |                  |  ^
+ *                   UNCERTAIN| |ENTERED     EXITED|  |UNCERTAIN
+ *                            | v                  v  |
+ *                        ________    EXITED     _________
+ *                       | Inside | -----------> | Outside |
+ *                       |        | <----------- |         |
+ *                        """"""""    ENTERED    """""""""
+ *
+ * Inside state: We are 95% confident that the user is inside the geofence.
+ * Outside state: We are 95% confident that the user is outside the geofence
+ * Unknown state: Rest of the time.
+ *
+ * The Unknown state is better explained with an example:
+ *
+ *                            __________
+ *                           |         c|
+ *                           |  ___     |    _______
+ *                           |  |a|     |   |   b   |
+ *                           |  """     |    """""""
+ *                           |          |
+ *                            """"""""""
+ * In the diagram above, "a" and "b" are 2 geofences and "c" is the accuracy
+ * circle reported by the GPS subsystem. Now with regard to "b", the system is
+ * confident that the user is outside. But with regard to "a" is not confident
+ * whether it is inside or outside the geofence. If the accuracy remains the
+ * same for a sufficient period of time, the UNCERTAIN transition would be
+ * triggered with the state set to Unknown. If the accuracy improves later, an
+ * appropriate transition should be triggered.  This "sufficient period of time"
+ * is defined by the parameter in the add_geofence_area API.
+ *     In other words, Unknown state can be interpreted as a state in which the
+ * GPS subsystem isn't confident enough that the user is either inside or
+ * outside the Geofence. It moves to Unknown state only after the expiry of the
+ * timeout.
+ *
+ * The geofence callback needs to be triggered for the ENTERED and EXITED
+ * transitions, when the GPS system is confident that the user has entered
+ * (Inside state) or exited (Outside state) the Geofence. An implementation
+ * which uses a value of 95% as the confidence is recommended. The callback
+ * should be triggered only for the transitions requested by the
+ * add_geofence_area call.
+ *
+ * Even though the diagram and explanation talks about states and transitions,
+ * the callee is only interested in the transistions. The states are mentioned
+ * here for illustrative purposes.
+ *
+ * Startup Scenario: When the device boots up, if an application adds geofences,
+ * and then we get an accurate GPS location fix, it needs to trigger the
+ * appropriate (ENTERED or EXITED) transition for every Geofence it knows about.
+ * By default, all the Geofences will be in the Unknown state.
+ *
+ * When the GPS system is unavailable, gps_geofence_status_callback should be
+ * called to inform the upper layers of the same. Similarly, when it becomes
+ * available the callback should be called. This is a global state while the
+ * UNKNOWN transition described above is per geofence.
+ *
+ * An important aspect to note is that users of this API (framework), will use
+ * other subsystems like wifi, sensors, cell to handle Unknown case and
+ * hopefully provide a definitive state transition to the third party
+ * application. GPS Geofence will just be a signal indicating what the GPS
+ * subsystem knows about the Geofence.
+ *
+ */
+#define GPS_GEOFENCE_ENTERED     (1<<0L)
+#define GPS_GEOFENCE_EXITED      (1<<1L)
+#define GPS_GEOFENCE_UNCERTAIN   (1<<2L)
+
+#define GPS_GEOFENCE_UNAVAILABLE (1<<0L)
+#define GPS_GEOFENCE_AVAILABLE   (1<<1L)
+
+#define GPS_GEOFENCE_OPERATION_SUCCESS           0
+#define GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES -100
+#define GPS_GEOFENCE_ERROR_ID_EXISTS          -101
+#define GPS_GEOFENCE_ERROR_ID_UNKNOWN         -102
+#define GPS_GEOFENCE_ERROR_INVALID_TRANSITION -103
+#define GPS_GEOFENCE_ERROR_GENERIC            -149
+/**
+* The callback associated with the geofence.
+* Parameters:
+*      geofence_id - The id associated with the add_geofence_area.
+*      location    - The current GPS location.
+*      transition  - Can be one of GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED,
+*                    GPS_GEOFENCE_UNCERTAIN.
+*      timestamp   - Timestamp when the transition was detected.
+*
+* The callback should only be called when the caller is interested in that
+* particular transition. For instance, if the caller is interested only in
+* ENTERED transition, then the callback should NOT be called with the EXITED
+* transition.
+*
+* IMPORTANT: If a transition is triggered resulting in this callback, the GPS
+* subsystem will wake up the application processor, if its in suspend state.
+*/
+typedef void (*gps_geofence_transition_callback) (int32_t geofence_id,  GpsLocation* location,
+int32_t transition, GpsUtcTime timestamp);
+
+/**
+ * The callback associated with the availablity of the GPS system for geofencing
+ * monitoring. If the GPS system determines that it cannot monitor geofences
+ * because of lack of reliability or unavailability of the GPS signals, it will
+ * call this callback with GPS_GEOFENCE_UNAVAILABLE parameter.
+ *
+ * Parameters:
+ *  status - GPS_GEOFENCE_UNAVAILABLE or GPS_GEOFENCE_AVAILABLE.
+ *  last_location - Last known location.
+ */
+typedef void (*gps_geofence_status_callback) (int32_t status, GpsLocation* last_location);
+
+/**
+ * The callback associated with the add_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES  - geofence limit has been reached.
+ *          GPS_GEOFENCE_ERROR_ID_EXISTS  - geofence with id already exists
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION - the monitorTransition contains an
+ *              invalid transition
+ *          GPS_GEOFENCE_ERROR_GENERIC - for other errors.
+ */
+typedef void (*gps_geofence_add_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the remove_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_remove_callback) (int32_t geofence_id, int32_t status);
+
+
+/**
+ * The callback associated with the pause_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION -
+ *                    when monitor_transitions is invalid
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_pause_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the resume_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_resume_callback) (int32_t geofence_id, int32_t status);
+
+typedef struct {
+    gps_geofence_transition_callback geofence_transition_callback;
+    gps_geofence_status_callback geofence_status_callback;
+    gps_geofence_add_callback geofence_add_callback;
+    gps_geofence_remove_callback geofence_remove_callback;
+    gps_geofence_pause_callback geofence_pause_callback;
+    gps_geofence_resume_callback geofence_resume_callback;
+    gps_create_thread create_thread_cb;
+} GpsGeofenceCallbacks;
+
+/** Extended interface for GPS_Geofencing support */
+typedef struct {
+    /** set to sizeof(GpsGeofencingInterface) */
+    size_t          size;
+
+    /**
+     * Opens the geofence interface and provides the callback routines
+     * to the implemenation of this interface.
+     */
+    void  (*init)( GpsGeofenceCallbacks* callbacks );
+
+    /**
+     * Add a geofence area. This api currently supports circular geofences.
+     * Parameters:
+     *    geofence_id - The id for the geofence. If a geofence with this id
+     *       already exists, an error value (GPS_GEOFENCE_ERROR_ID_EXISTS)
+     *       should be returned.
+     *    latitude, longtitude, radius_meters - The lat, long and radius
+     *       (in meters) for the geofence
+     *    last_transition - The current state of the geofence. For example, if
+     *       the system already knows that the user is inside the geofence,
+     *       this will be set to GPS_GEOFENCE_ENTERED. In most cases, it
+     *       will be GPS_GEOFENCE_UNCERTAIN.
+     *    monitor_transition - Which transitions to monitor. Bitwise OR of
+     *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+     *       GPS_GEOFENCE_UNCERTAIN.
+     *    notification_responsiveness_ms - Defines the best-effort description
+     *       of how soon should the callback be called when the transition
+     *       associated with the Geofence is triggered. For instance, if set
+     *       to 1000 millseconds with GPS_GEOFENCE_ENTERED, the callback
+     *       should be called 1000 milliseconds within entering the geofence.
+     *       This parameter is defined in milliseconds.
+     *       NOTE: This is not to be confused with the rate that the GPS is
+     *       polled at. It is acceptable to dynamically vary the rate of
+     *       sampling the GPS for power-saving reasons; thus the rate of
+     *       sampling may be faster or slower than this.
+     *    unknown_timer_ms - The time limit after which the UNCERTAIN transition
+     *       should be triggered. This paramter is defined in milliseconds.
+     *       See above for a detailed explanation.
+     */
+    void (*add_geofence_area) (int32_t geofence_id, double latitude,
+                               double longitude, double radius_meters,
+                               int last_transition, int monitor_transitions,
+                               int notification_responsiveness_ms,
+                               int unknown_timer_ms);
+
+    /**
+     * Pause monitoring a particular geofence.
+     * Parameters:
+     *   geofence_id - The id for the geofence.
+     */
+    void (*pause_geofence) (int32_t geofence_id);
+
+    /**
+     * Resume monitoring a particular geofence.
+     * Parameters:
+     *   geofence_id - The id for the geofence.
+     *   monitor_transitions - Which transitions to monitor. Bitwise OR of
+     *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+     *       GPS_GEOFENCE_UNCERTAIN.
+     *       This supersedes the value associated provided in the
+     *       add_geofence_area call.
+     */
+    void (*resume_geofence) (int32_t geofence_id, int monitor_transitions);
+
+    /**
+     * Remove a geofence area. After the function returns, no notifications
+     * should be sent.
+     * Parameter:
+     *   geofence_id - The id for the geofence.
+     */
+    void (*remove_geofence_area) (int32_t geofence_id);
+} GpsGeofencingInterface;
+__END_DECLS
+
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_H */
+