Merge "GNSS Model Name constant string and comment updates" into pi-dev
diff --git a/api/current.txt b/api/current.txt
index 6a9f00e..5cfd29a 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -21818,7 +21818,6 @@
     method public void unregisterGnssMeasurementsCallback(android.location.GnssMeasurementsEvent.Callback);
     method public void unregisterGnssNavigationMessageCallback(android.location.GnssNavigationMessage.Callback);
     method public void unregisterGnssStatusCallback(android.location.GnssStatus.Callback);
-    field public static final java.lang.String GNSS_HARDWARE_MODEL_NAME_UNKNOWN = "Model Name Unknown";
     field public static final java.lang.String GPS_PROVIDER = "gps";
     field public static final java.lang.String KEY_LOCATION_CHANGED = "location";
     field public static final java.lang.String KEY_PROVIDER_ENABLED = "providerEnabled";
diff --git a/location/java/android/location/LocationManager.java b/location/java/android/location/LocationManager.java
index c16876b..a523958 100644
--- a/location/java/android/location/LocationManager.java
+++ b/location/java/android/location/LocationManager.java
@@ -23,6 +23,7 @@
 
 import android.Manifest;
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.annotation.RequiresFeature;
 import android.annotation.RequiresPermission;
 import android.annotation.SuppressLint;
@@ -236,12 +237,6 @@
         "android.location.HIGH_POWER_REQUEST_CHANGE";
 
     /**
-     * The value returned by {@link LocationManager#getGnssHardwareModelName()} when the hardware
-     * does not support providing the actual value.
-     */
-    public static final String GNSS_HARDWARE_MODEL_NAME_UNKNOWN = "Model Name Unknown";
-
-    /**
      * Broadcast intent action for Settings app to inject a footer at the bottom of location
      * settings.
      *
@@ -2206,7 +2201,9 @@
     /**
      * Returns the model year of the GNSS hardware and software build.
      *
-     * May return 0 if the model year is less than 2016.
+     * <p> More details, such as build date, may be available in {@link #getGnssHardwareModelName()}.
+     *
+     * <p> May return 0 if the model year is less than 2016.
      */
     public int getGnssYearOfHardware() {
         try {
@@ -2220,10 +2217,12 @@
      * Returns the Model Name (including Vendor and Hardware/Software Version) of the GNSS hardware
      * driver.
      *
-     * Will return {@link LocationManager#GNSS_HARDWARE_MODEL_NAME_UNKNOWN} when the GNSS hardware
-     * abstraction layer does not support providing this value.
+     * <p> No device-specific serial number or ID is returned from this API.
+     *
+     * <p> Will return null when the GNSS hardware abstraction layer does not support providing
+     * this value.
      */
-    @NonNull
+    @Nullable
     public String getGnssHardwareModelName() {
         try {
             return mService.getGnssHardwareModelName();
diff --git a/services/core/java/com/android/server/LocationManagerService.java b/services/core/java/com/android/server/LocationManagerService.java
index d5cbfd4..26b83f5 100644
--- a/services/core/java/com/android/server/LocationManagerService.java
+++ b/services/core/java/com/android/server/LocationManagerService.java
@@ -19,6 +19,7 @@
 import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.app.ActivityManager;
 import android.app.AppOpsManager;
 import android.app.PendingIntent;
@@ -1131,11 +1132,12 @@
      * Returns the model name of the GNSS hardware.
      */
     @Override
+    @Nullable
     public String getGnssHardwareModelName() {
         if (mGnssSystemInfoProvider != null) {
             return mGnssSystemInfoProvider.getGnssHardwareModelName();
         } else {
-            return LocationManager.GNSS_HARDWARE_MODEL_NAME_UNKNOWN;
+            return null;
         }
     }
 
diff --git a/services/core/java/com/android/server/location/GnssLocationProvider.java b/services/core/java/com/android/server/location/GnssLocationProvider.java
index e02feec..8f0e1da 100644
--- a/services/core/java/com/android/server/location/GnssLocationProvider.java
+++ b/services/core/java/com/android/server/location/GnssLocationProvider.java
@@ -470,7 +470,7 @@
 
     // Volatile for simple inter-thread sync on these values.
     private volatile int mHardwareYear = 0;
-    private volatile String mHardwareModelName = LocationManager.GNSS_HARDWARE_MODEL_NAME_UNKNOWN;
+    private volatile String mHardwareModelName;
 
     // Set lower than the current ITAR limit of 600m/s to allow this to trigger even if GPS HAL
     // stops output right at 600m/s, depriving this of the information of a device that reaches