Add default impl of Sensors HAL 2.1

Create a default implementation of HAL 2.1 that shares 90% of the
underlying code with HAL 2.0 since the interfaces are very similar.

Bug: 144139857
Test: compile
Change-Id: Ic6b139df98ddb1f92833b1f2d65e1cecc297fd41

17 files changed, 748 insertions, 492 deletions

diff --git a/sensors/2.0/default/Android.bp b/sensors/2.0/default/Android.bp
index 62c9487319..bb383273a6 100644
--- a/sensors/2.0/default/Android.bp
+++ b/sensors/2.0/default/Android.bp
@@ -20,13 +20,17 @@ cc_binary {
     relative_install_path: "hw",
     srcs: [
         "service.cpp",
-        "Sensor.cpp",
-        "Sensors.cpp",
     ],
     init_rc: ["android.hardware.sensors@2.0-service-mock.rc"],
+    header_libs: [
+        "android.hardware.sensors@2.X-shared-utils",
+    ],
     shared_libs: [
         "android.hardware.sensors@1.0",
         "android.hardware.sensors@2.0",
+        // Needed to compile some shared utilities for both 2.0/2.1 impls, but
+        // isn't normally needed for a HAL that only supports 2.0.
+        "android.hardware.sensors@2.1",
         "libcutils",
         "libfmq",
         "libhidlbase",
@@ -34,5 +38,9 @@ cc_binary {
         "libpower",
         "libutils",
     ],
+    static_libs: [
+        "android.hardware.sensors@1.0-convert",
+        "android.hardware.sensors@2.X-shared-impl",
+    ],
     vintf_fragments: ["android.hardware.sensors@2.0.xml"],
 }
diff --git a/sensors/2.0/default/Sensors.cpp b/sensors/2.0/default/Sensors.cpp
deleted file mode 100644
index 23dd26bccb..0000000000
--- a/sensors/2.0/default/Sensors.cpp
+++ /dev/null
@@ -1,259 +0,0 @@
-/*
- * 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.
- */
-
-#include "Sensors.h"
-
-#include <android/hardware/sensors/2.0/types.h>
-#include <log/log.h>
-
-namespace android {
-namespace hardware {
-namespace sensors {
-namespace V2_0 {
-namespace implementation {
-
-using ::android::hardware::sensors::V1_0::Event;
-using ::android::hardware::sensors::V1_0::OperationMode;
-using ::android::hardware::sensors::V1_0::RateLevel;
-using ::android::hardware::sensors::V1_0::Result;
-using ::android::hardware::sensors::V1_0::SharedMemInfo;
-using ::android::hardware::sensors::V2_0::SensorTimeout;
-using ::android::hardware::sensors::V2_0::WakeLockQueueFlagBits;
-
-constexpr const char* kWakeLockName = "SensorsHAL_WAKEUP";
-
-Sensors::Sensors()
-    : mEventQueueFlag(nullptr),
-      mNextHandle(1),
-      mOutstandingWakeUpEvents(0),
-      mReadWakeLockQueueRun(false),
-      mAutoReleaseWakeLockTime(0),
-      mHasWakeLock(false) {
-    AddSensor<AccelSensor>();
-    AddSensor<GyroSensor>();
-    AddSensor<AmbientTempSensor>();
-    AddSensor<DeviceTempSensor>();
-    AddSensor<PressureSensor>();
-    AddSensor<MagnetometerSensor>();
-    AddSensor<LightSensor>();
-    AddSensor<ProximitySensor>();
-    AddSensor<RelativeHumiditySensor>();
-}
-
-Sensors::~Sensors() {
-    deleteEventFlag();
-    mReadWakeLockQueueRun = false;
-    mWakeLockThread.join();
-}
-
-// Methods from ::android::hardware::sensors::V2_0::ISensors follow.
-Return<void> Sensors::getSensorsList(getSensorsList_cb _hidl_cb) {
-    std::vector<SensorInfo> sensors;
-    for (const auto& sensor : mSensors) {
-        sensors.push_back(sensor.second->getSensorInfo());
-    }
-
-    // Call the HIDL callback with the SensorInfo
-    _hidl_cb(sensors);
-
-    return Void();
-}
-
-Return<Result> Sensors::setOperationMode(OperationMode mode) {
-    for (auto sensor : mSensors) {
-        sensor.second->setOperationMode(mode);
-    }
-    return Result::OK;
-}
-
-Return<Result> Sensors::activate(int32_t sensorHandle, bool enabled) {
-    auto sensor = mSensors.find(sensorHandle);
-    if (sensor != mSensors.end()) {
-        sensor->second->activate(enabled);
-        return Result::OK;
-    }
-    return Result::BAD_VALUE;
-}
-
-Return<Result> Sensors::initialize(
-    const ::android::hardware::MQDescriptorSync<Event>& eventQueueDescriptor,
-    const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
-    const sp<ISensorsCallback>& sensorsCallback) {
-    Result result = Result::OK;
-
-    // Ensure that all sensors are disabled
-    for (auto sensor : mSensors) {
-        sensor.second->activate(false /* enable */);
-    }
-
-    // Stop the Wake Lock thread if it is currently running
-    if (mReadWakeLockQueueRun.load()) {
-        mReadWakeLockQueueRun = false;
-        mWakeLockThread.join();
-    }
-
-    // Save a reference to the callback
-    mCallback = sensorsCallback;
-
-    // Create the Event FMQ from the eventQueueDescriptor. Reset the read/write positions.
-    mEventQueue =
-        std::make_unique<EventMessageQueue>(eventQueueDescriptor, true /* resetPointers */);
-
-    // Ensure that any existing EventFlag is properly deleted
-    deleteEventFlag();
-
-    // Create the EventFlag that is used to signal to the framework that sensor events have been
-    // written to the Event FMQ
-    if (EventFlag::createEventFlag(mEventQueue->getEventFlagWord(), &mEventQueueFlag) != OK) {
-        result = Result::BAD_VALUE;
-    }
-
-    // Create the Wake Lock FMQ that is used by the framework to communicate whenever WAKE_UP
-    // events have been successfully read and handled by the framework.
-    mWakeLockQueue =
-        std::make_unique<WakeLockMessageQueue>(wakeLockDescriptor, true /* resetPointers */);
-
-    if (!mCallback || !mEventQueue || !mWakeLockQueue || mEventQueueFlag == nullptr) {
-        result = Result::BAD_VALUE;
-    }
-
-    // Start the thread to read events from the Wake Lock FMQ
-    mReadWakeLockQueueRun = true;
-    mWakeLockThread = std::thread(startReadWakeLockThread, this);
-
-    return result;
-}
-
-Return<Result> Sensors::batch(int32_t sensorHandle, int64_t samplingPeriodNs,
-                              int64_t /* maxReportLatencyNs */) {
-    auto sensor = mSensors.find(sensorHandle);
-    if (sensor != mSensors.end()) {
-        sensor->second->batch(samplingPeriodNs);
-        return Result::OK;
-    }
-    return Result::BAD_VALUE;
-}
-
-Return<Result> Sensors::flush(int32_t sensorHandle) {
-    auto sensor = mSensors.find(sensorHandle);
-    if (sensor != mSensors.end()) {
-        return sensor->second->flush();
-    }
-    return Result::BAD_VALUE;
-}
-
-Return<Result> Sensors::injectSensorData(const Event& event) {
-    auto sensor = mSensors.find(event.sensorHandle);
-    if (sensor != mSensors.end()) {
-        return sensor->second->injectEvent(event);
-    }
-
-    return Result::BAD_VALUE;
-}
-
-Return<void> Sensors::registerDirectChannel(const SharedMemInfo& /* mem */,
-                                            registerDirectChannel_cb _hidl_cb) {
-    _hidl_cb(Result::INVALID_OPERATION, -1 /* channelHandle */);
-    return Return<void>();
-}
-
-Return<Result> Sensors::unregisterDirectChannel(int32_t /* channelHandle */) {
-    return Result::INVALID_OPERATION;
-}
-
-Return<void> Sensors::configDirectReport(int32_t /* sensorHandle */, int32_t /* channelHandle */,
-                                         RateLevel /* rate */, configDirectReport_cb _hidl_cb) {
-    _hidl_cb(Result::INVALID_OPERATION, 0 /* reportToken */);
-    return Return<void>();
-}
-
-void Sensors::postEvents(const std::vector<Event>& events, bool wakeup) {
-    std::lock_guard<std::mutex> lock(mWriteLock);
-    if (mEventQueue->write(events.data(), events.size())) {
-        mEventQueueFlag->wake(static_cast<uint32_t>(EventQueueFlagBits::READ_AND_PROCESS));
-
-        if (wakeup) {
-            // Keep track of the number of outstanding WAKE_UP events in order to properly hold
-            // a wake lock until the framework has secured a wake lock
-            updateWakeLock(events.size(), 0 /* eventsHandled */);
-        }
-    }
-}
-
-void Sensors::updateWakeLock(int32_t eventsWritten, int32_t eventsHandled) {
-    std::lock_guard<std::mutex> lock(mWakeLockLock);
-    int32_t newVal = mOutstandingWakeUpEvents + eventsWritten - eventsHandled;
-    if (newVal < 0) {
-        mOutstandingWakeUpEvents = 0;
-    } else {
-        mOutstandingWakeUpEvents = newVal;
-    }
-
-    if (eventsWritten > 0) {
-        // Update the time at which the last WAKE_UP event was sent
-        mAutoReleaseWakeLockTime = ::android::uptimeMillis() +
-                                   static_cast<uint32_t>(SensorTimeout::WAKE_LOCK_SECONDS) * 1000;
-    }
-
-    if (!mHasWakeLock && mOutstandingWakeUpEvents > 0 &&
-        acquire_wake_lock(PARTIAL_WAKE_LOCK, kWakeLockName) == 0) {
-        mHasWakeLock = true;
-    } else if (mHasWakeLock) {
-        // Check if the wake lock should be released automatically if
-        // SensorTimeout::WAKE_LOCK_SECONDS has elapsed since the last WAKE_UP event was written to
-        // the Wake Lock FMQ.
-        if (::android::uptimeMillis() > mAutoReleaseWakeLockTime) {
-            ALOGD("No events read from wake lock FMQ for %d seconds, auto releasing wake lock",
-                  SensorTimeout::WAKE_LOCK_SECONDS);
-            mOutstandingWakeUpEvents = 0;
-        }
-
-        if (mOutstandingWakeUpEvents == 0 && release_wake_lock(kWakeLockName) == 0) {
-            mHasWakeLock = false;
-        }
-    }
-}
-
-void Sensors::readWakeLockFMQ() {
-    while (mReadWakeLockQueueRun.load()) {
-        constexpr int64_t kReadTimeoutNs = 500 * 1000 * 1000;  // 500 ms
-        uint32_t eventsHandled = 0;
-
-        // Read events from the Wake Lock FMQ. Timeout after a reasonable amount of time to ensure
-        // that any held wake lock is able to be released if it is held for too long.
-        mWakeLockQueue->readBlocking(&eventsHandled, 1 /* count */, 0 /* readNotification */,
-                                     static_cast<uint32_t>(WakeLockQueueFlagBits::DATA_WRITTEN),
-                                     kReadTimeoutNs);
-        updateWakeLock(0 /* eventsWritten */, eventsHandled);
-    }
-}
-
-void Sensors::startReadWakeLockThread(Sensors* sensors) {
-    sensors->readWakeLockFMQ();
-}
-
-void Sensors::deleteEventFlag() {
-    status_t status = EventFlag::deleteEventFlag(&mEventQueueFlag);
-    if (status != OK) {
-        ALOGI("Failed to delete event flag: %d", status);
-    }
-}
-
-}  // namespace implementation
-}  // namespace V2_0
-}  // namespace sensors
-}  // namespace hardware
-}  // namespace android
diff --git a/sensors/2.0/default/Sensors.h b/sensors/2.0/default/Sensors.h
deleted file mode 100644
index d06dd78dad..0000000000
--- a/sensors/2.0/default/Sensors.h
+++ /dev/null
@@ -1,191 +0,0 @@
-/*
- * 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.
- */
-
-#ifndef ANDROID_HARDWARE_SENSORS_V2_0_SENSORS_H
-#define ANDROID_HARDWARE_SENSORS_V2_0_SENSORS_H
-
-#include "Sensor.h"
-
-#include <android/hardware/sensors/2.0/ISensors.h>
-#include <fmq/MessageQueue.h>
-#include <hardware_legacy/power.h>
-#include <hidl/MQDescriptor.h>
-#include <hidl/Status.h>
-
-#include <atomic>
-#include <memory>
-#include <thread>
-
-namespace android {
-namespace hardware {
-namespace sensors {
-namespace V2_0 {
-namespace implementation {
-
-using ::android::sp;
-using ::android::hardware::EventFlag;
-using ::android::hardware::hidl_array;
-using ::android::hardware::hidl_memory;
-using ::android::hardware::hidl_string;
-using ::android::hardware::hidl_vec;
-using ::android::hardware::MessageQueue;
-using ::android::hardware::MQDescriptor;
-using ::android::hardware::Return;
-using ::android::hardware::Void;
-
-struct Sensors : public ISensors, public ISensorsEventCallback {
-    using Event = ::android::hardware::sensors::V1_0::Event;
-    using OperationMode = ::android::hardware::sensors::V1_0::OperationMode;
-    using RateLevel = ::android::hardware::sensors::V1_0::RateLevel;
-    using Result = ::android::hardware::sensors::V1_0::Result;
-    using SharedMemInfo = ::android::hardware::sensors::V1_0::SharedMemInfo;
-
-    Sensors();
-    virtual ~Sensors();
-
-    // Methods from ::android::hardware::sensors::V2_0::ISensors follow.
-    Return<void> getSensorsList(getSensorsList_cb _hidl_cb) override;
-
-    Return<Result> setOperationMode(OperationMode mode) override;
-
-    Return<Result> activate(int32_t sensorHandle, bool enabled) override;
-
-    Return<Result> initialize(
-        const ::android::hardware::MQDescriptorSync<Event>& eventQueueDescriptor,
-        const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
-        const sp<ISensorsCallback>& sensorsCallback) override;
-
-    Return<Result> batch(int32_t sensorHandle, int64_t samplingPeriodNs,
-                         int64_t maxReportLatencyNs) override;
-
-    Return<Result> flush(int32_t sensorHandle) override;
-
-    Return<Result> injectSensorData(const Event& event) override;
-
-    Return<void> registerDirectChannel(const SharedMemInfo& mem,
-                                       registerDirectChannel_cb _hidl_cb) override;
-
-    Return<Result> unregisterDirectChannel(int32_t channelHandle) override;
-
-    Return<void> configDirectReport(int32_t sensorHandle, int32_t channelHandle, RateLevel rate,
-                                    configDirectReport_cb _hidl_cb) override;
-
-    void postEvents(const std::vector<Event>& events, bool wakeup) override;
-
-   private:
-    /**
-     * Add a new sensor
-     */
-    template <class SensorType>
-    void AddSensor() {
-        std::shared_ptr<SensorType> sensor =
-                std::make_shared<SensorType>(mNextHandle++ /* sensorHandle */, this /* callback */);
-        mSensors[sensor->getSensorInfo().sensorHandle] = sensor;
-    }
-
-    /**
-     * Utility function to delete the Event Flag
-     */
-    void deleteEventFlag();
-
-    /**
-     * Function to read the Wake Lock FMQ and release the wake lock when appropriate
-     */
-    void readWakeLockFMQ();
-
-    static void startReadWakeLockThread(Sensors* sensors);
-
-    /**
-     * Responsible for acquiring and releasing a wake lock when there are unhandled WAKE_UP events
-     */
-    void updateWakeLock(int32_t eventsWritten, int32_t eventsHandled);
-
-    using EventMessageQueue = MessageQueue<Event, kSynchronizedReadWrite>;
-    using WakeLockMessageQueue = MessageQueue<uint32_t, kSynchronizedReadWrite>;
-
-    /**
-     * The Event FMQ where sensor events are written
-     */
-    std::unique_ptr<EventMessageQueue> mEventQueue;
-
-    /**
-     * The Wake Lock FMQ that is read to determine when the framework has handled WAKE_UP events
-     */
-    std::unique_ptr<WakeLockMessageQueue> mWakeLockQueue;
-
-    /**
-     * Event Flag to signal to the framework when sensor events are available to be read
-     */
-    EventFlag* mEventQueueFlag;
-
-    /**
-     * Callback for asynchronous events, such as dynamic sensor connections.
-     */
-    sp<ISensorsCallback> mCallback;
-
-    /**
-     * A map of the available sensors
-     */
-    std::map<int32_t, std::shared_ptr<Sensor>> mSensors;
-
-    /**
-     * The next available sensor handle
-     */
-    int32_t mNextHandle;
-
-    /**
-     * Lock to protect writes to the FMQs
-     */
-    std::mutex mWriteLock;
-
-    /**
-     * Lock to protect acquiring and releasing the wake lock
-     */
-    std::mutex mWakeLockLock;
-
-    /**
-     * Track the number of WAKE_UP events that have not been handled by the framework
-     */
-    uint32_t mOutstandingWakeUpEvents;
-
-    /**
-     * A thread to read the Wake Lock FMQ
-     */
-    std::thread mWakeLockThread;
-
-    /**
-     * Flag to indicate that the Wake Lock Thread should continue to run
-     */
-    std::atomic_bool mReadWakeLockQueueRun;
-
-    /**
-     * Track the time when the wake lock should automatically be released
-     */
-    int64_t mAutoReleaseWakeLockTime;
-
-    /**
-     * Flag to indicate if a wake lock has been acquired
-     */
-    bool mHasWakeLock;
-};
-
-}  // namespace implementation
-}  // namespace V2_0
-}  // namespace sensors
-}  // namespace hardware
-}  // namespace android
-
-#endif  // ANDROID_HARDWARE_SENSORS_V2_0_SENSORS_H
diff --git a/sensors/2.0/default/SensorsV2_0.h b/sensors/2.0/default/SensorsV2_0.h
new file mode 100644
index 0000000000..345835a186
--- /dev/null
+++ b/sensors/2.0/default/SensorsV2_0.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2020 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_HARDWARE_SENSORS_V2_0_H
+#define ANDROID_HARDWARE_SENSORS_V2_0_H
+
+#include "Sensors.h"
+
+#include <android/hardware/sensors/2.0/ISensors.h>
+
+namespace android {
+namespace hardware {
+namespace sensors {
+namespace V2_0 {
+namespace implementation {
+
+struct SensorsV2_0 : public ::android::hardware::sensors::V2_X::implementation::Sensors<ISensors> {
+};
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace sensors
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_SENSORS_V2_0_H
\ No newline at end of file
diff --git a/sensors/2.0/default/service.cpp b/sensors/2.0/default/service.cpp
index 5c13e331d0..e20bf85df3 100644
--- a/sensors/2.0/default/service.cpp
+++ b/sensors/2.0/default/service.cpp
@@ -20,17 +20,17 @@
 #include <hidl/HidlTransportSupport.h>
 #include <log/log.h>
 #include <utils/StrongPointer.h>
-#include "Sensors.h"
+#include "SensorsV2_0.h"
 
 using android::hardware::configureRpcThreadpool;
 using android::hardware::joinRpcThreadpool;
 using android::hardware::sensors::V2_0::ISensors;
-using android::hardware::sensors::V2_0::implementation::Sensors;
+using android::hardware::sensors::V2_0::implementation::SensorsV2_0;
 
 int main(int /* argc */, char** /* argv */) {
     configureRpcThreadpool(1, true);
 
-    android::sp<ISensors> sensors = new Sensors();
+    android::sp<ISensors> sensors = new SensorsV2_0();
     if (sensors->registerAsService() != ::android::OK) {
         ALOGE("Failed to register Sensors HAL instance");
         return -1;
diff --git a/sensors/2.1/default/Android.bp b/sensors/2.1/default/Android.bp
new file mode 100644
index 0000000000..27b439d422
--- /dev/null
+++ b/sensors/2.1/default/Android.bp
@@ -0,0 +1,45 @@
+//
+// 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.
+
+cc_binary {
+    name: "android.hardware.sensors@2.1-service.mock",
+    defaults: ["hidl_defaults"],
+    vendor: true,
+    relative_install_path: "hw",
+    srcs: [
+        "SensorsV2_1.cpp",
+        "service.cpp",
+    ],
+    init_rc: ["android.hardware.sensors@2.1-service-mock.rc"],
+    header_libs: [
+        "android.hardware.sensors@2.X-shared-utils",
+    ],
+    shared_libs: [
+        "android.hardware.sensors@1.0",
+        "android.hardware.sensors@2.0",
+        "android.hardware.sensors@2.1",
+        "libcutils",
+        "libfmq",
+        "libhidlbase",
+        "liblog",
+        "libpower",
+        "libutils",
+    ],
+    static_libs: [
+        "android.hardware.sensors@1.0-convert",
+        "android.hardware.sensors@2.X-shared-impl",
+    ],
+    vintf_fragments: ["android.hardware.sensors@2.1.xml"],
+}
diff --git a/sensors/2.1/default/OWNERS b/sensors/2.1/default/OWNERS
new file mode 100644
index 0000000000..90c233030e
--- /dev/null
+++ b/sensors/2.1/default/OWNERS
@@ -0,0 +1,3 @@
+arthuri@google.com
+bduddie@google.com
+stange@google.com
diff --git a/sensors/2.1/default/SensorsV2_1.cpp b/sensors/2.1/default/SensorsV2_1.cpp
new file mode 100644
index 0000000000..adf874ebac
--- /dev/null
+++ b/sensors/2.1/default/SensorsV2_1.cpp
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#include "SensorsV2_1.h"
+
+namespace android {
+namespace hardware {
+namespace sensors {
+namespace V2_1 {
+namespace implementation {
+
+// Methods from ::android::hardware::sensors::V2_1::ISensors follow.
+Return<void> SensorsV2_1::getSensorsList_2_1(ISensors::getSensorsList_2_1_cb _hidl_cb) {
+    std::vector<SensorInfo> sensors;
+    for (const auto& sensor : mSensors) {
+        sensors.push_back(convertToNewSensorInfo(sensor.second->getSensorInfo()));
+    }
+
+    // Call the HIDL callback with the SensorInfo
+    _hidl_cb(sensors);
+
+    return Void();
+}
+
+Return<Result> SensorsV2_1::initialize_2_1(
+        const ::android::hardware::MQDescriptorSync<V2_1::Event>& eventQueueDescriptor,
+        const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
+        const sp<V2_1::ISensorsCallback>& sensorsCallback) {
+    auto eventQueue = std::make_unique<MessageQueue<V2_1::Event, kSynchronizedReadWrite>>(
+            eventQueueDescriptor, true /* resetPointers */);
+    std::unique_ptr<EventMessageQueueWrapperBase> wrapper =
+            std::make_unique<EventMessageQueueWrapperV2_1>(eventQueue);
+    mCallbackWrapper = new ISensorsCallbackWrapper(sensorsCallback);
+    return initializeBase(wrapper, wakeLockDescriptor, mCallbackWrapper);
+}
+
+Return<Result> SensorsV2_1::injectSensorData_2_1(const V2_1::Event& event) {
+    return injectSensorData(convertToOldEvent(event));
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace sensors
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/sensors/2.1/default/SensorsV2_1.h b/sensors/2.1/default/SensorsV2_1.h
new file mode 100644
index 0000000000..9cd16a7ec3
--- /dev/null
+++ b/sensors/2.1/default/SensorsV2_1.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2020 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_HARDWARE_SENSORS_V2_1_H
+#define ANDROID_HARDWARE_SENSORS_V2_1_H
+
+#include "Sensors.h"
+
+#include "EventMessageQueueWrapper.h"
+
+#include <android/hardware/sensors/2.1/ISensors.h>
+
+namespace android {
+namespace hardware {
+namespace sensors {
+namespace V2_1 {
+namespace implementation {
+
+using Result = ::android::hardware::sensors::V1_0::Result;
+using Sensors = ::android::hardware::sensors::V2_X::implementation::Sensors<ISensors>;
+
+class ISensorsCallbackWrapper : public V2_0::ISensorsCallback {
+  public:
+    ISensorsCallbackWrapper(const sp<V2_1::ISensorsCallback>& callback) : mCallback(callback) {}
+
+    Return<void> onDynamicSensorsConnected(const hidl_vec<V1_0::SensorInfo>& sensorInfos) override {
+        return mCallback->onDynamicSensorsConnected_2_1(convertToNewSensorInfos(sensorInfos));
+    }
+
+    Return<void> onDynamicSensorsDisconnected(const hidl_vec<int32_t>& sensorHandles) override {
+        return mCallback->onDynamicSensorsDisconnected(sensorHandles);
+    }
+
+  private:
+    sp<V2_1::ISensorsCallback> mCallback;
+};
+
+struct SensorsV2_1 : public Sensors {
+    // Methods from ::android::hardware::sensors::V2_1::ISensors follow.
+    Return<void> getSensorsList_2_1(ISensors::getSensorsList_2_1_cb _hidl_cb) override;
+
+    Return<Result> initialize_2_1(
+            const ::android::hardware::MQDescriptorSync<V2_1::Event>& eventQueueDescriptor,
+            const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
+            const sp<V2_1::ISensorsCallback>& sensorsCallback) override;
+
+    Return<Result> injectSensorData_2_1(const V2_1::Event& event) override;
+
+  private:
+    sp<ISensorsCallbackWrapper> mCallbackWrapper;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace sensors
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_SENSORS_V2_1_H
\ No newline at end of file
diff --git a/sensors/2.1/default/android.hardware.sensors@2.1-service-mock.rc b/sensors/2.1/default/android.hardware.sensors@2.1-service-mock.rc
new file mode 100644
index 0000000000..d4147e75da
--- /dev/null
+++ b/sensors/2.1/default/android.hardware.sensors@2.1-service-mock.rc
@@ -0,0 +1,7 @@
+service vendor.sensors-hal-2-1-mock /vendor/bin/hw/android.hardware.sensors@2.1-service.mock
+    interface android.hardware.sensors@2.0::ISensors default
+    interface android.hardware.sensors@2.1::ISensors default
+    class hal
+    user system
+    group system
+    rlimit rtprio 10 10
diff --git a/sensors/2.1/default/android.hardware.sensors@2.1.xml b/sensors/2.1/default/android.hardware.sensors@2.1.xml
new file mode 100644
index 0000000000..18bd3ae83b
--- /dev/null
+++ b/sensors/2.1/default/android.hardware.sensors@2.1.xml
@@ -0,0 +1,11 @@
+<manifest version="1.0" type="device">
+    <hal format="hidl">
+        <name>android.hardware.sensors</name>
+        <transport>hwbinder</transport>
+        <version>2.1</version>
+        <interface>
+            <name>ISensors</name>
+            <instance>default</instance>
+        </interface>
+    </hal>
+</manifest>
diff --git a/sensors/2.1/default/service.cpp b/sensors/2.1/default/service.cpp
new file mode 100644
index 0000000000..1f3087c1fd
--- /dev/null
+++ b/sensors/2.1/default/service.cpp
@@ -0,0 +1,41 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "android.hardware.sensors@2.1-service"
+
+#include <android/hardware/sensors/2.1/ISensors.h>
+#include <hidl/HidlTransportSupport.h>
+#include <log/log.h>
+#include <utils/StrongPointer.h>
+#include "SensorsV2_1.h"
+
+using android::hardware::configureRpcThreadpool;
+using android::hardware::joinRpcThreadpool;
+using android::hardware::sensors::V2_1::ISensors;
+using android::hardware::sensors::V2_1::implementation::SensorsV2_1;
+
+int main(int /* argc */, char** /* argv */) {
+    configureRpcThreadpool(1, true);
+
+    android::sp<ISensors> sensors = new SensorsV2_1();
+    if (sensors->registerAsService() != ::android::OK) {
+        ALOGE("Failed to register Sensors HAL instance");
+        return -1;
+    }
+
+    joinRpcThreadpool();
+    return 1;  // joinRpcThreadpool shouldn't exit
+}
diff --git a/sensors/common/default/2.X/Android.bp b/sensors/common/default/2.X/Android.bp
new file mode 100644
index 0000000000..ea75a104bd
--- /dev/null
+++ b/sensors/common/default/2.X/Android.bp
@@ -0,0 +1,36 @@
+//
+// Copyright (C) 2020 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.
+
+cc_library_static {
+    name: "android.hardware.sensors@2.X-shared-impl",
+    vendor: true,
+    export_include_dirs: ["."],
+    srcs: [
+        "Sensor.cpp",
+    ],
+    header_libs: [
+        "android.hardware.sensors@2.X-shared-utils",
+    ],
+    shared_libs: [
+        "android.hardware.sensors@1.0",
+        "android.hardware.sensors@2.0",
+        "libcutils",
+        "libfmq",
+        "libhidlbase",
+        "liblog",
+        "libpower",
+        "libutils",
+    ],
+}
diff --git a/sensors/common/default/2.X/OWNERS b/sensors/common/default/2.X/OWNERS
new file mode 100644
index 0000000000..90c233030e
--- /dev/null
+++ b/sensors/common/default/2.X/OWNERS
@@ -0,0 +1,3 @@
+arthuri@google.com
+bduddie@google.com
+stange@google.com
diff --git a/sensors/2.0/default/Sensor.cpp b/sensors/common/default/2.X/Sensor.cpp
index c09173f7ce..4c40d1f33b 100644
--- a/sensors/2.0/default/Sensor.cpp
+++ b/sensors/common/default/2.X/Sensor.cpp
@@ -23,12 +23,17 @@
 namespace android {
 namespace hardware {
 namespace sensors {
-namespace V2_0 {
+namespace V2_X {
 namespace implementation {
 
+using ::android::hardware::sensors::V1_0::Event;
 using ::android::hardware::sensors::V1_0::MetaDataEventType;
+using ::android::hardware::sensors::V1_0::OperationMode;
+using ::android::hardware::sensors::V1_0::Result;
 using ::android::hardware::sensors::V1_0::SensorFlagBits;
+using ::android::hardware::sensors::V1_0::SensorInfo;
 using ::android::hardware::sensors::V1_0::SensorStatus;
+using ::android::hardware::sensors::V1_0::SensorType;
 
 static constexpr float kDefaultMaxDelayUs = 10 * 1000 * 1000;
 
@@ -204,8 +209,8 @@ AccelSensor::AccelSensor(int32_t sensorHandle, ISensorsEventCallback* callback)
     mSensorInfo.typeAsString = "";
     mSensorInfo.maxRange = 78.4f;  // +/- 8g
     mSensorInfo.resolution = 1.52e-5;
-    mSensorInfo.power = 0.001f;          // mA
-    mSensorInfo.minDelay = 20 * 1000;    // microseconds
+    mSensorInfo.power = 0.001f;        // mA
+    mSensorInfo.minDelay = 20 * 1000;  // microseconds
     mSensorInfo.maxDelay = kDefaultMaxDelayUs;
     mSensorInfo.fifoReservedEventCount = 0;
     mSensorInfo.fifoMaxEventCount = 0;
@@ -221,9 +226,9 @@ PressureSensor::PressureSensor(int32_t sensorHandle, ISensorsEventCallback* call
     mSensorInfo.version = 1;
     mSensorInfo.type = SensorType::PRESSURE;
     mSensorInfo.typeAsString = "";
-    mSensorInfo.maxRange = 1100.0f;   // hPa
-    mSensorInfo.resolution = 0.005f;  // hPa
-    mSensorInfo.power = 0.001f;       // mA
+    mSensorInfo.maxRange = 1100.0f;     // hPa
+    mSensorInfo.resolution = 0.005f;    // hPa
+    mSensorInfo.power = 0.001f;         // mA
     mSensorInfo.minDelay = 100 * 1000;  // microseconds
     mSensorInfo.maxDelay = kDefaultMaxDelayUs;
     mSensorInfo.fifoReservedEventCount = 0;
@@ -242,7 +247,7 @@ MagnetometerSensor::MagnetometerSensor(int32_t sensorHandle, ISensorsEventCallba
     mSensorInfo.typeAsString = "";
     mSensorInfo.maxRange = 1300.0f;
     mSensorInfo.resolution = 0.01f;
-    mSensorInfo.power = 0.001f;       // mA
+    mSensorInfo.power = 0.001f;        // mA
     mSensorInfo.minDelay = 20 * 1000;  // microseconds
     mSensorInfo.maxDelay = kDefaultMaxDelayUs;
     mSensorInfo.fifoReservedEventCount = 0;
@@ -261,8 +266,8 @@ LightSensor::LightSensor(int32_t sensorHandle, ISensorsEventCallback* callback)
     mSensorInfo.typeAsString = "";
     mSensorInfo.maxRange = 43000.0f;
     mSensorInfo.resolution = 10.0f;
-    mSensorInfo.power = 0.001f;           // mA
-    mSensorInfo.minDelay = 200 * 1000;    // microseconds
+    mSensorInfo.power = 0.001f;         // mA
+    mSensorInfo.minDelay = 200 * 1000;  // microseconds
     mSensorInfo.maxDelay = kDefaultMaxDelayUs;
     mSensorInfo.fifoReservedEventCount = 0;
     mSensorInfo.fifoMaxEventCount = 0;
@@ -280,7 +285,7 @@ ProximitySensor::ProximitySensor(int32_t sensorHandle, ISensorsEventCallback* ca
     mSensorInfo.typeAsString = "";
     mSensorInfo.maxRange = 5.0f;
     mSensorInfo.resolution = 1.0f;
-    mSensorInfo.power = 0.012f;  // mA
+    mSensorInfo.power = 0.012f;         // mA
     mSensorInfo.minDelay = 200 * 1000;  // microseconds
     mSensorInfo.maxDelay = kDefaultMaxDelayUs;
     mSensorInfo.fifoReservedEventCount = 0;
@@ -367,7 +372,7 @@ RelativeHumiditySensor::RelativeHumiditySensor(int32_t sensorHandle,
 }
 
 }  // namespace implementation
-}  // namespace V2_0
+}  // namespace V2_X
 }  // namespace sensors
 }  // namespace hardware
 }  // namespace android
diff --git a/sensors/2.0/default/Sensor.h b/sensors/common/default/2.X/Sensor.h
index 61900fa436..8592c412a4 100644
--- a/sensors/2.0/default/Sensor.h
+++ b/sensors/common/default/2.X/Sensor.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_HARDWARE_SENSORS_V2_0_SENSOR_H
-#define ANDROID_HARDWARE_SENSORS_V2_0_SENSOR_H
+#ifndef ANDROID_HARDWARE_SENSORS_V2_X_SENSOR_H
+#define ANDROID_HARDWARE_SENSORS_V2_X_SENSOR_H
 
 #include <android/hardware/sensors/1.0/types.h>
 
@@ -25,26 +25,28 @@
 #include <thread>
 #include <vector>
 
-using ::android::hardware::sensors::V1_0::Event;
-using ::android::hardware::sensors::V1_0::OperationMode;
-using ::android::hardware::sensors::V1_0::Result;
-using ::android::hardware::sensors::V1_0::SensorInfo;
-using ::android::hardware::sensors::V1_0::SensorType;
-
 namespace android {
 namespace hardware {
 namespace sensors {
-namespace V2_0 {
+namespace V2_X {
 namespace implementation {
 
 class ISensorsEventCallback {
-   public:
+  public:
+    using Event = ::android::hardware::sensors::V1_0::Event;
+
     virtual ~ISensorsEventCallback(){};
     virtual void postEvents(const std::vector<Event>& events, bool wakeup) = 0;
 };
 
 class Sensor {
-   public:
+  public:
+    using Event = ::android::hardware::sensors::V1_0::Event;
+    using OperationMode = ::android::hardware::sensors::V1_0::OperationMode;
+    using Result = ::android::hardware::sensors::V1_0::Result;
+    using SensorInfo = ::android::hardware::sensors::V1_0::SensorInfo;
+    using SensorType = ::android::hardware::sensors::V1_0::SensorType;
+
     Sensor(ISensorsEventCallback* callback);
     virtual ~Sensor();
 
@@ -57,7 +59,7 @@ class Sensor {
     bool supportsDataInjection() const;
     Result injectEvent(const Event& event);
 
-   protected:
+  protected:
     void run();
     virtual std::vector<Event> readEvents();
     static void startThread(Sensor* sensor);
@@ -80,68 +82,68 @@ class Sensor {
 };
 
 class OnChangeSensor : public Sensor {
-   public:
+  public:
     OnChangeSensor(ISensorsEventCallback* callback);
 
     virtual void activate(bool enable) override;
 
-   protected:
+  protected:
     virtual std::vector<Event> readEvents() override;
 
-   protected:
+  protected:
     Event mPreviousEvent;
     bool mPreviousEventSet;
 };
 
 class AccelSensor : public Sensor {
-   public:
+  public:
     AccelSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class GyroSensor : public Sensor {
-   public:
+  public:
     GyroSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class AmbientTempSensor : public OnChangeSensor {
-   public:
+  public:
     AmbientTempSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class DeviceTempSensor : public OnChangeSensor {
-   public:
+  public:
     DeviceTempSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class PressureSensor : public Sensor {
-   public:
+  public:
     PressureSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class MagnetometerSensor : public Sensor {
-   public:
+  public:
     MagnetometerSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class LightSensor : public OnChangeSensor {
-   public:
+  public:
     LightSensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class ProximitySensor : public OnChangeSensor {
-   public:
+  public:
     ProximitySensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 class RelativeHumiditySensor : public OnChangeSensor {
-   public:
+  public:
     RelativeHumiditySensor(int32_t sensorHandle, ISensorsEventCallback* callback);
 };
 
 }  // namespace implementation
-}  // namespace V2_0
+}  // namespace V2_X
 }  // namespace sensors
 }  // namespace hardware
 }  // namespace android
 
-#endif  // ANDROID_HARDWARE_SENSORS_V2_0_SENSOR_H
+#endif  // ANDROID_HARDWARE_SENSORS_V2_X_SENSOR_H
diff --git a/sensors/common/default/2.X/Sensors.h b/sensors/common/default/2.X/Sensors.h
new file mode 100644
index 0000000000..de998ebb05
--- /dev/null
+++ b/sensors/common/default/2.X/Sensors.h
@@ -0,0 +1,376 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_HARDWARE_SENSORS_V2_X_SENSORS_H
+#define ANDROID_HARDWARE_SENSORS_V2_X_SENSORS_H
+
+#include "EventMessageQueueWrapper.h"
+#include "Sensor.h"
+
+#include <android/hardware/sensors/2.0/ISensors.h>
+#include <android/hardware/sensors/2.0/types.h>
+#include <fmq/MessageQueue.h>
+#include <hardware_legacy/power.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <log/log.h>
+
+#include <atomic>
+#include <memory>
+#include <thread>
+
+namespace android {
+namespace hardware {
+namespace sensors {
+namespace V2_X {
+namespace implementation {
+
+template <class ISensorsInterface>
+struct Sensors : public ISensorsInterface, public ISensorsEventCallback {
+    using Event = ::android::hardware::sensors::V1_0::Event;
+    using OperationMode = ::android::hardware::sensors::V1_0::OperationMode;
+    using RateLevel = ::android::hardware::sensors::V1_0::RateLevel;
+    using Result = ::android::hardware::sensors::V1_0::Result;
+    using SharedMemInfo = ::android::hardware::sensors::V1_0::SharedMemInfo;
+    using EventQueueFlagBits = ::android::hardware::sensors::V2_0::EventQueueFlagBits;
+    using SensorTimeout = ::android::hardware::sensors::V2_0::SensorTimeout;
+    using WakeLockQueueFlagBits = ::android::hardware::sensors::V2_0::WakeLockQueueFlagBits;
+    using ISensorsCallback = ::android::hardware::sensors::V2_0::ISensorsCallback;
+    using EventMessageQueue = MessageQueue<Event, kSynchronizedReadWrite>;
+    using WakeLockMessageQueue = MessageQueue<uint32_t, kSynchronizedReadWrite>;
+
+    static constexpr const char* kWakeLockName = "SensorsHAL_WAKEUP";
+
+    Sensors()
+        : mEventQueueFlag(nullptr),
+          mNextHandle(1),
+          mOutstandingWakeUpEvents(0),
+          mReadWakeLockQueueRun(false),
+          mAutoReleaseWakeLockTime(0),
+          mHasWakeLock(false) {
+        AddSensor<AccelSensor>();
+        AddSensor<GyroSensor>();
+        AddSensor<AmbientTempSensor>();
+        AddSensor<DeviceTempSensor>();
+        AddSensor<PressureSensor>();
+        AddSensor<MagnetometerSensor>();
+        AddSensor<LightSensor>();
+        AddSensor<ProximitySensor>();
+        AddSensor<RelativeHumiditySensor>();
+    }
+
+    virtual ~Sensors() {
+        deleteEventFlag();
+        mReadWakeLockQueueRun = false;
+        mWakeLockThread.join();
+    }
+
+    // Methods from ::android::hardware::sensors::V2_0::ISensors follow.
+    Return<void> getSensorsList(V2_0::ISensors::getSensorsList_cb _hidl_cb) override {
+        std::vector<V1_0::SensorInfo> sensors;
+        for (const auto& sensor : mSensors) {
+            sensors.push_back(sensor.second->getSensorInfo());
+        }
+
+        // Call the HIDL callback with the SensorInfo
+        _hidl_cb(sensors);
+
+        return Void();
+    }
+
+    Return<Result> setOperationMode(OperationMode mode) override {
+        for (auto sensor : mSensors) {
+            sensor.second->setOperationMode(mode);
+        }
+        return Result::OK;
+    }
+
+    Return<Result> activate(int32_t sensorHandle, bool enabled) override {
+        auto sensor = mSensors.find(sensorHandle);
+        if (sensor != mSensors.end()) {
+            sensor->second->activate(enabled);
+            return Result::OK;
+        }
+        return Result::BAD_VALUE;
+    }
+
+    Return<Result> initialize(
+            const ::android::hardware::MQDescriptorSync<Event>& eventQueueDescriptor,
+            const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
+            const sp<ISensorsCallback>& sensorsCallback) override {
+        auto eventQueue =
+                std::make_unique<EventMessageQueue>(eventQueueDescriptor, true /* resetPointers */);
+        std::unique_ptr<V2_1::implementation::EventMessageQueueWrapperBase> wrapper =
+                std::make_unique<V2_1::implementation::EventMessageQueueWrapperV1_0>(eventQueue);
+        return initializeBase(wrapper, wakeLockDescriptor, sensorsCallback);
+    }
+
+    Return<Result> initializeBase(
+            std::unique_ptr<V2_1::implementation::EventMessageQueueWrapperBase>& eventQueue,
+            const ::android::hardware::MQDescriptorSync<uint32_t>& wakeLockDescriptor,
+            const sp<ISensorsCallback>& sensorsCallback) {
+        Result result = Result::OK;
+
+        // Ensure that all sensors are disabled
+        for (auto sensor : mSensors) {
+            sensor.second->activate(false /* enable */);
+        }
+
+        // Stop the Wake Lock thread if it is currently running
+        if (mReadWakeLockQueueRun.load()) {
+            mReadWakeLockQueueRun = false;
+            mWakeLockThread.join();
+        }
+
+        // Save a reference to the callback
+        mCallback = sensorsCallback;
+
+        // Save the event queue.
+        mEventQueue = std::move(eventQueue);
+
+        // Ensure that any existing EventFlag is properly deleted
+        deleteEventFlag();
+
+        // Create the EventFlag that is used to signal to the framework that sensor events have been
+        // written to the Event FMQ
+        if (EventFlag::createEventFlag(mEventQueue->getEventFlagWord(), &mEventQueueFlag) != OK) {
+            result = Result::BAD_VALUE;
+        }
+
+        // Create the Wake Lock FMQ that is used by the framework to communicate whenever WAKE_UP
+        // events have been successfully read and handled by the framework.
+        mWakeLockQueue = std::make_unique<WakeLockMessageQueue>(wakeLockDescriptor,
+                                                                true /* resetPointers */);
+
+        if (!mCallback || !mEventQueue || !mWakeLockQueue || mEventQueueFlag == nullptr) {
+            result = Result::BAD_VALUE;
+        }
+
+        // Start the thread to read events from the Wake Lock FMQ
+        mReadWakeLockQueueRun = true;
+        mWakeLockThread = std::thread(startReadWakeLockThread, this);
+
+        return result;
+    }
+
+    Return<Result> batch(int32_t sensorHandle, int64_t samplingPeriodNs,
+                         int64_t /* maxReportLatencyNs */) override {
+        auto sensor = mSensors.find(sensorHandle);
+        if (sensor != mSensors.end()) {
+            sensor->second->batch(samplingPeriodNs);
+            return Result::OK;
+        }
+        return Result::BAD_VALUE;
+    }
+
+    Return<Result> flush(int32_t sensorHandle) override {
+        auto sensor = mSensors.find(sensorHandle);
+        if (sensor != mSensors.end()) {
+            return sensor->second->flush();
+        }
+        return Result::BAD_VALUE;
+    }
+
+    Return<Result> injectSensorData(const Event& event) override {
+        auto sensor = mSensors.find(event.sensorHandle);
+        if (sensor != mSensors.end()) {
+            return sensor->second->injectEvent(event);
+        }
+
+        return Result::BAD_VALUE;
+    }
+
+    Return<void> registerDirectChannel(const SharedMemInfo& /* mem */,
+                                       V2_0::ISensors::registerDirectChannel_cb _hidl_cb) override {
+        _hidl_cb(Result::INVALID_OPERATION, -1 /* channelHandle */);
+        return Return<void>();
+    }
+
+    Return<Result> unregisterDirectChannel(int32_t /* channelHandle */) override {
+        return Result::INVALID_OPERATION;
+    }
+
+    Return<void> configDirectReport(int32_t /* sensorHandle */, int32_t /* channelHandle */,
+                                    RateLevel /* rate */,
+                                    V2_0::ISensors::configDirectReport_cb _hidl_cb) override {
+        _hidl_cb(Result::INVALID_OPERATION, 0 /* reportToken */);
+        return Return<void>();
+    }
+
+    void postEvents(const std::vector<Event>& events, bool wakeup) override {
+        std::lock_guard<std::mutex> lock(mWriteLock);
+        if (mEventQueue->write(V2_1::implementation::convertToNewEvents(events))) {
+            mEventQueueFlag->wake(static_cast<uint32_t>(EventQueueFlagBits::READ_AND_PROCESS));
+
+            if (wakeup) {
+                // Keep track of the number of outstanding WAKE_UP events in order to properly hold
+                // a wake lock until the framework has secured a wake lock
+                updateWakeLock(events.size(), 0 /* eventsHandled */);
+            }
+        }
+    }
+
+  protected:
+    /**
+     * Add a new sensor
+     */
+    template <class SensorType>
+    void AddSensor() {
+        std::shared_ptr<SensorType> sensor =
+                std::make_shared<SensorType>(mNextHandle++ /* sensorHandle */, this /* callback */);
+        mSensors[sensor->getSensorInfo().sensorHandle] = sensor;
+    }
+
+    /**
+     * Utility function to delete the Event Flag
+     */
+    void deleteEventFlag() {
+        status_t status = EventFlag::deleteEventFlag(&mEventQueueFlag);
+        if (status != OK) {
+            ALOGI("Failed to delete event flag: %d", status);
+        }
+    }
+
+    static void startReadWakeLockThread(Sensors* sensors) { sensors->readWakeLockFMQ(); }
+
+    /**
+     * Function to read the Wake Lock FMQ and release the wake lock when appropriate
+     */
+    void readWakeLockFMQ() {
+        while (mReadWakeLockQueueRun.load()) {
+            constexpr int64_t kReadTimeoutNs = 500 * 1000 * 1000;  // 500 ms
+            uint32_t eventsHandled = 0;
+
+            // Read events from the Wake Lock FMQ. Timeout after a reasonable amount of time to
+            // ensure that any held wake lock is able to be released if it is held for too long.
+            mWakeLockQueue->readBlocking(&eventsHandled, 1 /* count */, 0 /* readNotification */,
+                                         static_cast<uint32_t>(WakeLockQueueFlagBits::DATA_WRITTEN),
+                                         kReadTimeoutNs);
+            updateWakeLock(0 /* eventsWritten */, eventsHandled);
+        }
+    }
+
+    /**
+     * Responsible for acquiring and releasing a wake lock when there are unhandled WAKE_UP events
+     */
+    void updateWakeLock(int32_t eventsWritten, int32_t eventsHandled) {
+        std::lock_guard<std::mutex> lock(mWakeLockLock);
+        int32_t newVal = mOutstandingWakeUpEvents + eventsWritten - eventsHandled;
+        if (newVal < 0) {
+            mOutstandingWakeUpEvents = 0;
+        } else {
+            mOutstandingWakeUpEvents = newVal;
+        }
+
+        if (eventsWritten > 0) {
+            // Update the time at which the last WAKE_UP event was sent
+            mAutoReleaseWakeLockTime =
+                    ::android::uptimeMillis() +
+                    static_cast<uint32_t>(SensorTimeout::WAKE_LOCK_SECONDS) * 1000;
+        }
+
+        if (!mHasWakeLock && mOutstandingWakeUpEvents > 0 &&
+            acquire_wake_lock(PARTIAL_WAKE_LOCK, kWakeLockName) == 0) {
+            mHasWakeLock = true;
+        } else if (mHasWakeLock) {
+            // Check if the wake lock should be released automatically if
+            // SensorTimeout::WAKE_LOCK_SECONDS has elapsed since the last WAKE_UP event was written
+            // to the Wake Lock FMQ.
+            if (::android::uptimeMillis() > mAutoReleaseWakeLockTime) {
+                ALOGD("No events read from wake lock FMQ for %d seconds, auto releasing wake lock",
+                      SensorTimeout::WAKE_LOCK_SECONDS);
+                mOutstandingWakeUpEvents = 0;
+            }
+
+            if (mOutstandingWakeUpEvents == 0 && release_wake_lock(kWakeLockName) == 0) {
+                mHasWakeLock = false;
+            }
+        }
+    }
+
+    /**
+     * The Event FMQ where sensor events are written
+     */
+    std::unique_ptr<V2_1::implementation::EventMessageQueueWrapperBase> mEventQueue;
+
+    /**
+     * The Wake Lock FMQ that is read to determine when the framework has handled WAKE_UP events
+     */
+    std::unique_ptr<WakeLockMessageQueue> mWakeLockQueue;
+
+    /**
+     * Event Flag to signal to the framework when sensor events are available to be read
+     */
+    EventFlag* mEventQueueFlag;
+
+    /**
+     * Callback for asynchronous events, such as dynamic sensor connections.
+     */
+    sp<ISensorsCallback> mCallback;
+
+    /**
+     * A map of the available sensors
+     */
+    std::map<int32_t, std::shared_ptr<Sensor>> mSensors;
+
+    /**
+     * The next available sensor handle
+     */
+    int32_t mNextHandle;
+
+    /**
+     * Lock to protect writes to the FMQs
+     */
+    std::mutex mWriteLock;
+
+    /**
+     * Lock to protect acquiring and releasing the wake lock
+     */
+    std::mutex mWakeLockLock;
+
+    /**
+     * Track the number of WAKE_UP events that have not been handled by the framework
+     */
+    uint32_t mOutstandingWakeUpEvents;
+
+    /**
+     * A thread to read the Wake Lock FMQ
+     */
+    std::thread mWakeLockThread;
+
+    /**
+     * Flag to indicate that the Wake Lock Thread should continue to run
+     */
+    std::atomic_bool mReadWakeLockQueueRun;
+
+    /**
+     * Track the time when the wake lock should automatically be released
+     */
+    int64_t mAutoReleaseWakeLockTime;
+
+    /**
+     * Flag to indicate if a wake lock has been acquired
+     */
+    bool mHasWakeLock;
+};
+
+}  // namespace implementation
+}  // namespace V2_X
+}  // namespace sensors
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_SENSORS_V2_X_SENSORS_H