Bluetooth Fast Pair

Enable advertisement of head unit as a connectable device via Fast Pair.
The fastPairModelId stored in the config file must be overriden by
vendors to their specific device Id.

Bug: 38321459
Test: runtest -x packages/services/Car/tests/carservice_test/ -c
com.android.car.FastPairProviderTest
Disable Restrictions and move Android phone close to Bluetooth
Antenna, observe Fast Pair dialog on phone.

Change-Id: Iae707849537c3ef3b16a2b0738a72007d3961741

1 files changed, 125 insertions, 0 deletions

diff --git a/service/src/com/android/car/FastPairProvider.java b/service/src/com/android/car/FastPairProvider.java
new file mode 100644
index 0000000000..ff5973236f
--- /dev/null
+++ b/service/src/com/android/car/FastPairProvider.java
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+package com.android.car;
+
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothManager;
+
+import android.bluetooth.le.AdvertiseCallback;
+import android.bluetooth.le.AdvertiseData;
+import android.bluetooth.le.AdvertiseSettings;
+import android.bluetooth.le.BluetoothLeAdvertiser;
+import android.content.Context;
+import android.content.res.Resources;
+import android.os.ParcelUuid;
+import android.util.Log;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Arrays;
+
+/**
+ * An advertiser for the Bluetooth LE based Fast Pair service.
+ * FastPairProvider enables easy Bluetooth pairing between a peripheral and a phone participating in
+ * the Fast Pair Seeker role.  When the seeker finds a compatible peripheral a notification prompts
+ * the user to begin pairing if desired.  A peripheral should call startAdvertising when it is
+ * appropriate to pair, and stopAdvertising when pairing is complete or it is no longer appropriate
+ * to pair.
+ */
+class FastPairProvider {
+
+    private static final String TAG = "FastPairProvider";
+    private static final boolean DBG = Utils.DBG;
+
+    // Service ID assigned for FastPair.
+    private static final ParcelUuid FastPairServiceUuid = ParcelUuid
+            .fromString("0000FE2C-0000-1000-8000-00805f9b34fb");
+
+    private AdvertiseSettings mSettings;
+    private AdvertiseData mData;
+    private BluetoothLeAdvertiser mBluetoothLeAdvertiser;
+    private AdvertiseCallback mAdvertiseCallback;
+
+
+    FastPairProvider(Context context) {
+        Resources res = context.getResources();
+        int modelId = res.getInteger(R.integer.fastPairModelId);
+        if (modelId == 0) {
+            Log.w(TAG, "Model ID undefined, disabling");
+            return;
+        }
+
+        BluetoothManager bluetoothManager = (BluetoothManager) context.getSystemService(
+                Context.BLUETOOTH_SERVICE);
+        if (bluetoothManager != null) {
+            BluetoothAdapter bluetoothAdapter = bluetoothManager.getAdapter();
+            if (bluetoothAdapter != null) {
+                mBluetoothLeAdvertiser = bluetoothAdapter.getBluetoothLeAdvertiser();
+            }
+        }
+
+        AdvertiseSettings.Builder settingsBuilder = new AdvertiseSettings.Builder();
+        settingsBuilder.setAdvertiseMode(AdvertiseSettings.ADVERTISE_MODE_LOW_LATENCY);
+        settingsBuilder.setTxPowerLevel(AdvertiseSettings.ADVERTISE_TX_POWER_HIGH);
+        settingsBuilder.setConnectable(true);
+        settingsBuilder.setTimeout(0);
+        mSettings = settingsBuilder.build();
+
+        AdvertiseData.Builder dataBuilder = new AdvertiseData.Builder();
+        ByteBuffer modelIdBytes = ByteBuffer.allocate(4).order(ByteOrder.LITTLE_ENDIAN).putInt(
+                modelId);
+        byte[] fastPairServiceData = Arrays.copyOfRange(modelIdBytes.array(), 0, 3);
+        dataBuilder.addServiceData(FastPairServiceUuid, fastPairServiceData);
+        dataBuilder.setIncludeTxPowerLevel(true).build();
+        mData = dataBuilder.build();
+
+        mAdvertiseCallback = new FastPairAdvertiseCallback();
+    }
+
+    /* register the BLE advertisement using the model id provided during construction */
+    boolean startAdvertising() {
+        if (mBluetoothLeAdvertiser != null) {
+            mBluetoothLeAdvertiser.startAdvertising(mSettings, mData, mAdvertiseCallback);
+            return true;
+        }
+        return false;
+    }
+
+    /* unregister the BLE advertisement. */
+    boolean stopAdvertising() {
+        if (mBluetoothLeAdvertiser != null) {
+            mBluetoothLeAdvertiser.stopAdvertising(mAdvertiseCallback);
+            return true;
+        }
+        return false;
+    }
+
+    /* Callback to handle status when advertising starts. */
+    private class FastPairAdvertiseCallback extends AdvertiseCallback {
+        @Override
+        public void onStartFailure(int errorCode) {
+            super.onStartFailure(errorCode);
+            if (DBG) Log.d(TAG, "Advertising failed");
+        }
+
+        @Override
+        public void onStartSuccess(AdvertiseSettings settingsInEffect) {
+            super.onStartSuccess(settingsInEffect);
+            if (DBG) Log.d(TAG, "Advertising successfully started");
+        }
+    }
+}