diff --git a/gnss/common/utils/default/Android.bp b/gnss/common/utils/default/Android.bp
index 2712e77..8d9d4d4 100644
--- a/gnss/common/utils/default/Android.bp
+++ b/gnss/common/utils/default/Android.bp
@@ -24,6 +24,11 @@
         "-Werror",
     ],
     srcs: [
+        "v2_1/GnssAntennaInfo.cpp",
+        "v2_1/GnssConfiguration.cpp",
+        "v2_1/GnssDebug.cpp",
+        "v2_1/GnssMeasurement.cpp",
+        "v2_1/GnssMeasurementCorrections.cpp",
         "Utils.cpp",
         "NmeaFixInfo.cpp",
     ],
@@ -34,5 +39,7 @@
         "android.hardware.gnss@1.0",
         "android.hardware.gnss@2.0",
         "android.hardware.gnss@2.1",
+        "android.hardware.gnss.measurement_corrections@1.1",
+        "android.hardware.gnss.measurement_corrections@1.0",
     ],
 }
diff --git a/gnss/common/utils/default/include/v2_1/GnssAntennaInfo.h b/gnss/common/utils/default/include/v2_1/GnssAntennaInfo.h
new file mode 100644
index 0000000..e74ff54
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssAntennaInfo.h
@@ -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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/2.1/IGnssAntennaInfo.h>
+
+#include <mutex>
+#include <thread>
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+using ::android::sp;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using IGnssAntennaInfo = ::android::hardware::gnss::V2_1::IGnssAntennaInfo;
+using IGnssAntennaInfoCallback = ::android::hardware::gnss::V2_1::IGnssAntennaInfoCallback;
+
+struct GnssAntennaInfo : public IGnssAntennaInfo {
+    GnssAntennaInfo();
+    ~GnssAntennaInfo();
+
+    // Methods from ::android::hardware::gnss::V2_1::IGnssAntennaInfo follow.
+    Return<GnssAntennaInfoStatus> setCallback(
+            const sp<IGnssAntennaInfoCallback>& callback) override;
+    Return<void> close() override;
+
+  private:
+    void start();
+    void stop();
+    void reportAntennaInfo(
+            const hidl_vec<IGnssAntennaInfoCallback::GnssAntennaInfo>& antennaInfo) const;
+
+    // Guarded by mMutex
+    static sp<IGnssAntennaInfoCallback> sCallback;
+
+    std::atomic<long> mMinIntervalMillis;
+    std::atomic<bool> mIsActive;
+    std::thread mThread;
+
+    // Synchronization lock for sCallback
+    mutable std::mutex mMutex;
+};
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/include/v2_1/GnssConfiguration.h b/gnss/common/utils/default/include/v2_1/GnssConfiguration.h
new file mode 100644
index 0000000..8463a5c
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssConfiguration.h
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/2.1/IGnssCallback.h>
+#include <android/hardware/gnss/2.1/IGnssConfiguration.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <mutex>
+#include <unordered_set>
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+using ::android::sp;
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_memory;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+
+using BlacklistedSourceV2_1 =
+        ::android::hardware::gnss::V2_1::IGnssConfiguration::BlacklistedSource;
+using GnssConstellationTypeV2_0 = V2_0::GnssConstellationType;
+using GnssSvInfoV2_1 = V2_1::IGnssCallback::GnssSvInfo;
+
+struct BlacklistedSourceHashV2_1 {
+    inline int operator()(const BlacklistedSourceV2_1& source) const {
+        return int(source.constellation) * 1000 + int(source.svid);
+    }
+};
+
+struct BlacklistedSourceEqualV2_1 {
+    inline bool operator()(const BlacklistedSourceV2_1& s1, const BlacklistedSourceV2_1& s2) const {
+        return (s1.constellation == s2.constellation) && (s1.svid == s2.svid);
+    }
+};
+
+using BlacklistedSourceSetV2_1 =
+        std::unordered_set<BlacklistedSourceV2_1, BlacklistedSourceHashV2_1,
+                           BlacklistedSourceEqualV2_1>;
+using BlacklistedConstellationSetV2_1 = std::unordered_set<GnssConstellationTypeV2_0>;
+
+struct GnssConfiguration : public IGnssConfiguration {
+    // Methods from ::android::hardware::gnss::V1_0::IGnssConfiguration follow.
+    Return<bool> setSuplEs(bool enabled) override;
+    Return<bool> setSuplVersion(uint32_t version) override;
+    Return<bool> setSuplMode(hidl_bitfield<SuplMode> mode) override;
+    Return<bool> setGpsLock(hidl_bitfield<GpsLock> lock) override;
+    Return<bool> setLppProfile(hidl_bitfield<LppProfile> lppProfile) override;
+    Return<bool> setGlonassPositioningProtocol(hidl_bitfield<GlonassPosProtocol> protocol) override;
+    Return<bool> setEmergencySuplPdn(bool enable) override;
+
+    // Methods from ::android::hardware::gnss::V1_1::IGnssConfiguration follow.
+    Return<bool> setBlacklist(
+            const hidl_vec<V1_1::IGnssConfiguration::BlacklistedSource>& blacklist) override;
+
+    std::recursive_mutex& getMutex() const;
+
+    // Methods from ::android::hardware::gnss::V2_0::IGnssConfiguration follow.
+    Return<bool> setEsExtensionSec(uint32_t emergencyExtensionSeconds) override;
+
+    // Methods from ::android::hardware::gnss::V2_1::IGnssConfiguration follow.
+    Return<bool> setBlacklist_2_1(
+            const hidl_vec<V2_1::IGnssConfiguration::BlacklistedSource>& blacklist) override;
+
+    Return<bool> isBlacklistedV2_1(const GnssSvInfoV2_1& gnssSvInfo) const;
+
+  private:
+    mutable std::recursive_mutex mMutex;
+
+    BlacklistedSourceSetV2_1 mBlacklistedSourceSet;
+    BlacklistedConstellationSetV2_1 mBlacklistedConstellationSet;
+};
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/include/v2_1/GnssDebug.h b/gnss/common/utils/default/include/v2_1/GnssDebug.h
new file mode 100644
index 0000000..8580989
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssDebug.h
@@ -0,0 +1,40 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/1.0/IGnssDebug.h>
+#include <hidl/Status.h>
+
+namespace android::hardware::gnss::V1_1::implementation {
+
+using ::android::sp;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using V1_0::IGnssDebug;
+
+/* Interface for GNSS Debug support. */
+struct GnssDebug : public IGnssDebug {
+    /*
+     * Methods from ::android::hardware::gnss::V1_0::IGnssDebug follow.
+     * These declarations were generated from IGnssDebug.hal.
+     */
+    Return<void> getDebugData(V1_0::IGnssDebug::getDebugData_cb _hidl_cb) override;
+};
+
+}  // namespace android::hardware::gnss::V1_1::implementation
diff --git a/gnss/common/utils/default/include/v2_1/GnssMeasurement.h b/gnss/common/utils/default/include/v2_1/GnssMeasurement.h
new file mode 100644
index 0000000..1d1fc9d
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssMeasurement.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/2.1/IGnssMeasurement.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <atomic>
+#include <mutex>
+#include <thread>
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+using GnssDataV2_1 = V2_1::IGnssMeasurementCallback::GnssData;
+using GnssDataV2_0 = V2_0::IGnssMeasurementCallback::GnssData;
+
+using ::android::sp;
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_memory;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+
+struct GnssMeasurement : public IGnssMeasurement {
+    GnssMeasurement();
+    ~GnssMeasurement();
+    // Methods from V1_0::IGnssMeasurement follow.
+    Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> setCallback(
+            const sp<V1_0::IGnssMeasurementCallback>& callback) override;
+    Return<void> close() override;
+
+    // Methods from V1_1::IGnssMeasurement follow.
+    Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> setCallback_1_1(
+            const sp<V1_1::IGnssMeasurementCallback>& callback, bool enableFullTracking) override;
+
+    // Methods from V2_0::IGnssMeasurement follow.
+    Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> setCallback_2_0(
+            const sp<V2_0::IGnssMeasurementCallback>& callback, bool enableFullTracking) override;
+
+    // Methods from V2_1::IGnssMeasurement follow.
+    Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> setCallback_2_1(
+            const sp<V2_1::IGnssMeasurementCallback>& callback, bool enableFullTracking) override;
+
+  private:
+    void start();
+    void stop();
+    void reportMeasurement(const GnssDataV2_0&);
+    void reportMeasurement(const GnssDataV2_1&);
+
+    // Guarded by mMutex
+    static sp<V2_1::IGnssMeasurementCallback> sCallback_2_1;
+
+    // Guarded by mMutex
+    static sp<V2_0::IGnssMeasurementCallback> sCallback_2_0;
+
+    std::atomic<long> mMinIntervalMillis;
+    std::atomic<bool> mIsActive;
+    std::thread mThread;
+
+    // Synchronization lock for sCallback_2_1 and sCallback_2_0
+    mutable std::mutex mMutex;
+};
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/include/v2_1/GnssMeasurementCorrections.h b/gnss/common/utils/default/include/v2_1/GnssMeasurementCorrections.h
new file mode 100644
index 0000000..eaa7659
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssMeasurementCorrections.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/measurement_corrections/1.1/IMeasurementCorrections.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+
+namespace android::hardware::gnss::measurement_corrections::V1_1::implementation {
+
+using ::android::sp;
+using ::android::hardware::Return;
+
+struct GnssMeasurementCorrections : public IMeasurementCorrections {
+    GnssMeasurementCorrections();
+    ~GnssMeasurementCorrections();
+
+    // Methods from V1_0::IMeasurementCorrections follow.
+    Return<bool> setCorrections(const V1_0::MeasurementCorrections& corrections) override;
+    Return<bool> setCallback(const sp<V1_0::IMeasurementCorrectionsCallback>& callback) override;
+
+    // Methods from V1_1::IMeasurementCorrections follow.
+    Return<bool> setCorrections_1_1(const V1_1::MeasurementCorrections& corrections) override;
+};
+
+}  // namespace android::hardware::gnss::measurement_corrections::V1_1::implementation
diff --git a/gnss/common/utils/default/include/v2_1/GnssTemplate.h b/gnss/common/utils/default/include/v2_1/GnssTemplate.h
new file mode 100644
index 0000000..d16a67b
--- /dev/null
+++ b/gnss/common/utils/default/include/v2_1/GnssTemplate.h
@@ -0,0 +1,641 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/2.1/IGnss.h>
+#include <fcntl.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+#include <log/log.h>
+#include <sys/epoll.h>
+#include <atomic>
+#include <mutex>
+#include <string>
+#include <thread>
+
+#include "GnssAntennaInfo.h"
+#include "GnssConfiguration.h"
+#include "GnssDebug.h"
+#include "GnssMeasurement.h"
+#include "GnssMeasurementCorrections.h"
+#include "NmeaFixInfo.h"
+#include "Utils.h"
+
+namespace android::hardware::gnss::common::implementation {
+
+using GnssSvInfo = V2_1::IGnssCallback::GnssSvInfo;
+
+using common::NmeaFixInfo;
+using common::Utils;
+using measurement_corrections::V1_1::implementation::GnssMeasurementCorrections;
+
+using V2_1::implementation::GnssAntennaInfo;
+using V2_1::implementation::GnssConfiguration;
+using V2_1::implementation::GnssMeasurement;
+
+constexpr int INPUT_BUFFER_SIZE = 128;
+constexpr char CMD_GET_LOCATION[] = "CMD_GET_LOCATION";
+constexpr char GNSS_PATH[] = "/dev/gnss0";
+
+template <class T_IGnss>
+struct GnssTemplate : public T_IGnss {
+    GnssTemplate();
+    ~GnssTemplate();
+    // Methods from V1_0::IGnss follow.
+    Return<bool> setCallback(const sp<V1_0::IGnssCallback>& callback) override;
+    Return<bool> start() override;
+    Return<bool> stop() override;
+    Return<void> cleanup() override;
+    Return<bool> injectTime(int64_t timeMs, int64_t timeReferenceMs,
+                            int32_t uncertaintyMs) override;
+    Return<bool> injectLocation(double latitudeDegrees, double longitudeDegrees,
+                                float accuracyMeters) override;
+    Return<void> deleteAidingData(V1_0::IGnss::GnssAidingData aidingDataFlags) override;
+    Return<bool> setPositionMode(V1_0::IGnss::GnssPositionMode mode,
+                                 V1_0::IGnss::GnssPositionRecurrence recurrence,
+                                 uint32_t minIntervalMs, uint32_t preferredAccuracyMeters,
+                                 uint32_t preferredTimeMs) override;
+    Return<sp<V1_0::IAGnssRil>> getExtensionAGnssRil() override;
+    Return<sp<V1_0::IGnssGeofencing>> getExtensionGnssGeofencing() override;
+    Return<sp<V1_0::IAGnss>> getExtensionAGnss() override;
+    Return<sp<V1_0::IGnssNi>> getExtensionGnssNi() override;
+    Return<sp<V1_0::IGnssMeasurement>> getExtensionGnssMeasurement() override;
+    Return<sp<V1_0::IGnssNavigationMessage>> getExtensionGnssNavigationMessage() override;
+    Return<sp<V1_0::IGnssXtra>> getExtensionXtra() override;
+    Return<sp<V1_0::IGnssConfiguration>> getExtensionGnssConfiguration() override;
+    Return<sp<V1_0::IGnssDebug>> getExtensionGnssDebug() override;
+    Return<sp<V1_0::IGnssBatching>> getExtensionGnssBatching() override;
+
+    // Methods from V1_1::IGnss follow.
+    Return<bool> setCallback_1_1(const sp<V1_1::IGnssCallback>& callback) override;
+    Return<bool> setPositionMode_1_1(V1_0::IGnss::GnssPositionMode mode,
+                                     V1_0::IGnss::GnssPositionRecurrence recurrence,
+                                     uint32_t minIntervalMs, uint32_t preferredAccuracyMeters,
+                                     uint32_t preferredTimeMs, bool lowPowerMode) override;
+    Return<sp<V1_1::IGnssConfiguration>> getExtensionGnssConfiguration_1_1() override;
+    Return<sp<V1_1::IGnssMeasurement>> getExtensionGnssMeasurement_1_1() override;
+    Return<bool> injectBestLocation(const V1_0::GnssLocation& location) override;
+
+    // Methods from V2_0::IGnss follow.
+    Return<bool> setCallback_2_0(const sp<V2_0::IGnssCallback>& callback) override;
+    Return<sp<V2_0::IGnssConfiguration>> getExtensionGnssConfiguration_2_0() override;
+    Return<sp<V2_0::IGnssDebug>> getExtensionGnssDebug_2_0() override;
+    Return<sp<V2_0::IAGnss>> getExtensionAGnss_2_0() override;
+    Return<sp<V2_0::IAGnssRil>> getExtensionAGnssRil_2_0() override;
+    Return<sp<V2_0::IGnssMeasurement>> getExtensionGnssMeasurement_2_0() override;
+    Return<sp<measurement_corrections::V1_0::IMeasurementCorrections>>
+    getExtensionMeasurementCorrections() override;
+    Return<sp<visibility_control::V1_0::IGnssVisibilityControl>> getExtensionVisibilityControl()
+            override;
+    Return<sp<V2_0::IGnssBatching>> getExtensionGnssBatching_2_0() override;
+    Return<bool> injectBestLocation_2_0(const V2_0::GnssLocation& location) override;
+
+    // Methods from V2_1::IGnss follow.
+    Return<bool> setCallback_2_1(const sp<V2_1::IGnssCallback>& callback) override;
+    Return<sp<V2_1::IGnssMeasurement>> getExtensionGnssMeasurement_2_1() override;
+    Return<sp<V2_1::IGnssConfiguration>> getExtensionGnssConfiguration_2_1() override;
+    Return<sp<measurement_corrections::V1_1::IMeasurementCorrections>>
+    getExtensionMeasurementCorrections_1_1() override;
+    Return<sp<V2_1::IGnssAntennaInfo>> getExtensionGnssAntennaInfo() override;
+
+  private:
+    std::unique_ptr<V2_0::GnssLocation> getLocationFromHW();
+    void reportLocation(const V2_0::GnssLocation&) const;
+    void reportLocation(const V1_0::GnssLocation&) const;
+    void reportSvStatus(const hidl_vec<GnssSvInfo>&) const;
+
+    static sp<V2_1::IGnssCallback> sGnssCallback_2_1;
+    static sp<V2_0::IGnssCallback> sGnssCallback_2_0;
+    static sp<V1_1::IGnssCallback> sGnssCallback_1_1;
+    static sp<V1_0::IGnssCallback> sGnssCallback_1_0;
+
+    std::atomic<long> mMinIntervalMs;
+    sp<GnssConfiguration> mGnssConfiguration;
+    std::atomic<bool> mIsActive;
+    std::atomic<bool> mHardwareModeOn;
+    std::atomic<int> mGnssFd;
+    std::thread mThread;
+
+    mutable std::mutex mMutex;
+    hidl_vec<GnssSvInfo> filterBlacklistedSatellitesV2_1(hidl_vec<GnssSvInfo> gnssSvInfoList);
+};
+
+template <class T_IGnss>
+sp<V2_1::IGnssCallback> GnssTemplate<T_IGnss>::sGnssCallback_2_1 = nullptr;
+template <class T_IGnss>
+sp<V2_0::IGnssCallback> GnssTemplate<T_IGnss>::sGnssCallback_2_0 = nullptr;
+template <class T_IGnss>
+sp<V1_1::IGnssCallback> GnssTemplate<T_IGnss>::sGnssCallback_1_1 = nullptr;
+template <class T_IGnss>
+sp<V1_0::IGnssCallback> GnssTemplate<T_IGnss>::sGnssCallback_1_0 = nullptr;
+
+template <class T_IGnss>
+GnssTemplate<T_IGnss>::GnssTemplate()
+    : mMinIntervalMs(1000),
+      mGnssConfiguration{new GnssConfiguration()},
+      mHardwareModeOn(false),
+      mGnssFd(-1) {}
+
+template <class T_IGnss>
+GnssTemplate<T_IGnss>::~GnssTemplate() {
+    stop();
+}
+
+template <class T_IGnss>
+std::unique_ptr<V2_0::GnssLocation> GnssTemplate<T_IGnss>::getLocationFromHW() {
+    char inputBuffer[INPUT_BUFFER_SIZE];
+    mHardwareModeOn = false;
+    if (mGnssFd == -1) {
+        mGnssFd = open(GNSS_PATH, O_RDWR | O_NONBLOCK);
+    }
+    if (mGnssFd == -1) {
+        return nullptr;
+    }
+    // Send control message to device
+    int bytes_write = write(mGnssFd, CMD_GET_LOCATION, strlen(CMD_GET_LOCATION));
+    if (bytes_write <= 0) {
+        return nullptr;
+    }
+
+    struct epoll_event ev, events[1];
+    ev.data.fd = mGnssFd;
+    ev.events = EPOLLIN;
+    int epoll_fd = epoll_create1(0);
+    epoll_ctl(epoll_fd, EPOLL_CTL_ADD, mGnssFd, &ev);
+    int bytes_read = -1;
+    std::string inputStr = "";
+    int epoll_ret = epoll_wait(epoll_fd, events, 1, mMinIntervalMs);
+    // Indicates it is a hardwareMode, don't need to wait outside.
+    mHardwareModeOn = true;
+    if (epoll_ret == -1) {
+        return nullptr;
+    }
+    while (true) {
+        bytes_read = read(mGnssFd, &inputBuffer, INPUT_BUFFER_SIZE);
+        if (bytes_read <= 0) {
+            break;
+        }
+        inputStr += std::string(inputBuffer, bytes_read);
+    }
+    return NmeaFixInfo::getLocationFromInputStr(inputStr);
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::start() {
+    if (mIsActive) {
+        ALOGW("Gnss has started. Restarting...");
+        stop();
+    }
+
+    mIsActive = true;
+    mThread = std::thread([this]() {
+        while (mIsActive == true) {
+            auto svStatus = filterBlacklistedSatellitesV2_1(Utils::getMockSvInfoListV2_1());
+            this->reportSvStatus(svStatus);
+
+            auto currentLocation = getLocationFromHW();
+            if (currentLocation != nullptr) {
+                this->reportLocation(*currentLocation);
+            } else {
+                if (sGnssCallback_2_1 != nullptr || sGnssCallback_2_0 != nullptr) {
+                    const auto location = Utils::getMockLocationV2_0();
+                    this->reportLocation(location);
+                } else {
+                    const auto location = Utils::getMockLocationV1_0();
+                    this->reportLocation(location);
+                }
+
+                // Only need do the sleep in the static location mode, which mocks the "wait
+                // for" hardware behavior.
+                if (!mHardwareModeOn) {
+                    std::this_thread::sleep_for(std::chrono::milliseconds(mMinIntervalMs));
+                }
+            }
+        }
+    });
+    return true;
+}
+
+template <class T_IGnss>
+hidl_vec<GnssSvInfo> GnssTemplate<T_IGnss>::filterBlacklistedSatellitesV2_1(
+        hidl_vec<GnssSvInfo> gnssSvInfoList) {
+    for (uint32_t i = 0; i < gnssSvInfoList.size(); i++) {
+        if (mGnssConfiguration->isBlacklistedV2_1(gnssSvInfoList[i])) {
+            gnssSvInfoList[i].v2_0.v1_0.svFlag &=
+                    ~static_cast<uint8_t>(V1_0::IGnssCallback::GnssSvFlags::USED_IN_FIX);
+        }
+    }
+    return gnssSvInfoList;
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::stop() {
+    ALOGD("stop");
+    mIsActive = false;
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+    if (mGnssFd != -1) {
+        close(mGnssFd);
+        mGnssFd = -1;
+    }
+    return true;
+}
+
+// Methods from V1_0::IGnss follow.
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setCallback(const sp<V1_0::IGnssCallback>& callback) {
+    if (callback == nullptr) {
+        ALOGE("%s: Null callback ignored", __func__);
+        return false;
+    }
+
+    sGnssCallback_1_0 = callback;
+
+    uint32_t capabilities = 0x0 | V1_0::IGnssCallback::Capabilities::MEASUREMENTS |
+                            V1_0::IGnssCallback::Capabilities::SCHEDULING;
+    auto ret = sGnssCallback_1_0->gnssSetCapabilitesCb(capabilities);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    V2_1::IGnssCallback::GnssSystemInfo gnssInfo = {.yearOfHw = 2018};
+
+    ret = sGnssCallback_1_0->gnssSetSystemInfoCb(gnssInfo);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    return true;
+}
+
+template <class T_IGnss>
+Return<void> GnssTemplate<T_IGnss>::cleanup() {
+    sGnssCallback_2_1 = nullptr;
+    sGnssCallback_2_0 = nullptr;
+    return Void();
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::injectTime(int64_t, int64_t, int32_t) {
+    return true;
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::injectLocation(double, double, float) {
+    return true;
+}
+
+template <class T_IGnss>
+Return<void> GnssTemplate<T_IGnss>::deleteAidingData(V1_0::IGnss::GnssAidingData) {
+    // TODO implement
+    return Void();
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setPositionMode(V1_0::IGnss::GnssPositionMode,
+                                                    V1_0::IGnss::GnssPositionRecurrence,
+                                                    uint32_t minIntervalMs, uint32_t, uint32_t) {
+    mMinIntervalMs = minIntervalMs;
+    return true;
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IAGnssRil>> GnssTemplate<T_IGnss>::getExtensionAGnssRil() {
+    // TODO implement
+    return ::android::sp<V1_0::IAGnssRil>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssGeofencing>> GnssTemplate<T_IGnss>::getExtensionGnssGeofencing() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssGeofencing>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IAGnss>> GnssTemplate<T_IGnss>::getExtensionAGnss() {
+    // TODO implement
+    return ::android::sp<V1_0::IAGnss>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssNi>> GnssTemplate<T_IGnss>::getExtensionGnssNi() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssNi>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssMeasurement>> GnssTemplate<T_IGnss>::getExtensionGnssMeasurement() {
+    ALOGD("Gnss::getExtensionGnssMeasurement");
+    return new GnssMeasurement();
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssNavigationMessage>>
+GnssTemplate<T_IGnss>::getExtensionGnssNavigationMessage() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssNavigationMessage>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssXtra>> GnssTemplate<T_IGnss>::getExtensionXtra() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssXtra>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssConfiguration>> GnssTemplate<T_IGnss>::getExtensionGnssConfiguration() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssConfiguration>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssDebug>> GnssTemplate<T_IGnss>::getExtensionGnssDebug() {
+    return new V1_1::implementation::GnssDebug();
+}
+
+template <class T_IGnss>
+Return<sp<V1_0::IGnssBatching>> GnssTemplate<T_IGnss>::getExtensionGnssBatching() {
+    // TODO implement
+    return ::android::sp<V1_0::IGnssBatching>{};
+}
+
+// Methods from V1_1::IGnss follow.
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setCallback_1_1(const sp<V1_1::IGnssCallback>& callback) {
+    if (callback == nullptr) {
+        ALOGE("%s: Null callback ignored", __func__);
+        return false;
+    }
+
+    sGnssCallback_1_1 = callback;
+
+    uint32_t capabilities = 0x0;
+    auto ret = sGnssCallback_1_1->gnssSetCapabilitesCb(capabilities);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    V2_1::IGnssCallback::GnssSystemInfo gnssInfo = {.yearOfHw = 2018};
+
+    ret = sGnssCallback_1_1->gnssSetSystemInfoCb(gnssInfo);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    auto gnssName = "Google Mock GNSS Implementation v2.1";
+    ret = sGnssCallback_1_1->gnssNameCb(gnssName);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    return true;
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setPositionMode_1_1(V1_0::IGnss::GnssPositionMode,
+                                                        V1_0::IGnss::GnssPositionRecurrence,
+                                                        uint32_t minIntervalMs, uint32_t, uint32_t,
+                                                        bool) {
+    mMinIntervalMs = minIntervalMs;
+    return true;
+}
+
+template <class T_IGnss>
+Return<sp<V1_1::IGnssConfiguration>> GnssTemplate<T_IGnss>::getExtensionGnssConfiguration_1_1() {
+    // TODO implement
+    return ::android::sp<V1_1::IGnssConfiguration>{};
+}
+
+template <class T_IGnss>
+Return<sp<V1_1::IGnssMeasurement>> GnssTemplate<T_IGnss>::getExtensionGnssMeasurement_1_1() {
+    // TODO implement
+    return ::android::sp<V1_1::IGnssMeasurement>{};
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::injectBestLocation(const V1_0::GnssLocation&) {
+    return true;
+}
+
+// Methods from V2_0::IGnss follow.
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setCallback_2_0(const sp<V2_0::IGnssCallback>& callback) {
+    ALOGD("Gnss::setCallback_2_0");
+    if (callback == nullptr) {
+        ALOGE("%s: Null callback ignored", __func__);
+        return false;
+    }
+
+    sGnssCallback_2_0 = callback;
+
+    using Capabilities = V2_0::IGnssCallback::Capabilities;
+    const auto capabilities = Capabilities::MEASUREMENTS | Capabilities::MEASUREMENT_CORRECTIONS |
+                              Capabilities::LOW_POWER_MODE | Capabilities::SATELLITE_BLACKLIST;
+    auto ret = sGnssCallback_2_0->gnssSetCapabilitiesCb_2_0(capabilities);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    V1_1::IGnssCallback::GnssSystemInfo gnssInfo = {.yearOfHw = 2019};
+
+    ret = sGnssCallback_2_0->gnssSetSystemInfoCb(gnssInfo);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    auto gnssName = "Google Mock GNSS Implementation v2.1";
+    ret = sGnssCallback_2_0->gnssNameCb(gnssName);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    return true;
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IGnssConfiguration>> GnssTemplate<T_IGnss>::getExtensionGnssConfiguration_2_0() {
+    ALOGD("Gnss::getExtensionGnssConfiguration_2_0");
+    return mGnssConfiguration;
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IGnssDebug>> GnssTemplate<T_IGnss>::getExtensionGnssDebug_2_0() {
+    // TODO implement
+    return ::android::sp<V2_0::IGnssDebug>{};
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IAGnss>> GnssTemplate<T_IGnss>::getExtensionAGnss_2_0() {
+    // TODO implement
+    return ::android::sp<V2_0::IAGnss>{};
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IAGnssRil>> GnssTemplate<T_IGnss>::getExtensionAGnssRil_2_0() {
+    // TODO implement
+    return ::android::sp<V2_0::IAGnssRil>{};
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IGnssMeasurement>> GnssTemplate<T_IGnss>::getExtensionGnssMeasurement_2_0() {
+    ALOGD("Gnss::getExtensionGnssMeasurement_2_0");
+    return new GnssMeasurement();
+}
+
+template <class T_IGnss>
+Return<sp<measurement_corrections::V1_0::IMeasurementCorrections>>
+GnssTemplate<T_IGnss>::getExtensionMeasurementCorrections() {
+    ALOGD("Gnss::getExtensionMeasurementCorrections()");
+    return new GnssMeasurementCorrections();
+}
+
+template <class T_IGnss>
+Return<sp<visibility_control::V1_0::IGnssVisibilityControl>>
+GnssTemplate<T_IGnss>::getExtensionVisibilityControl() {
+    // TODO implement
+    return ::android::sp<visibility_control::V1_0::IGnssVisibilityControl>{};
+}
+
+template <class T_IGnss>
+Return<sp<V2_0::IGnssBatching>> GnssTemplate<T_IGnss>::getExtensionGnssBatching_2_0() {
+    // TODO implement
+    return ::android::sp<V2_0::IGnssBatching>{};
+}
+
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::injectBestLocation_2_0(const V2_0::GnssLocation&) {
+    // TODO(b/124012850): Implement function.
+    return bool{};
+}
+
+// Methods from V2_1::IGnss follow.
+template <class T_IGnss>
+Return<bool> GnssTemplate<T_IGnss>::setCallback_2_1(const sp<V2_1::IGnssCallback>& callback) {
+    ALOGD("Gnss::setCallback_2_1");
+    if (callback == nullptr) {
+        ALOGE("%s: Null callback ignored", __func__);
+        return false;
+    }
+
+    sGnssCallback_2_1 = callback;
+
+    using Capabilities = V2_1::IGnssCallback::Capabilities;
+    const auto capabilities = Capabilities::MEASUREMENTS | Capabilities::MEASUREMENT_CORRECTIONS |
+                              Capabilities::LOW_POWER_MODE | Capabilities::SATELLITE_BLACKLIST |
+                              Capabilities::ANTENNA_INFO;
+    auto ret = sGnssCallback_2_1->gnssSetCapabilitiesCb_2_1(capabilities);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    V1_1::IGnssCallback::GnssSystemInfo gnssInfo = {.yearOfHw = 2020};
+
+    ret = sGnssCallback_2_1->gnssSetSystemInfoCb(gnssInfo);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    auto gnssName = "Android Mock GNSS Implementation v2.1";
+    ret = sGnssCallback_2_1->gnssNameCb(gnssName);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+
+    return true;
+}
+
+template <class T_IGnss>
+Return<sp<V2_1::IGnssMeasurement>> GnssTemplate<T_IGnss>::getExtensionGnssMeasurement_2_1() {
+    ALOGD("Gnss::getExtensionGnssMeasurement_2_1");
+    return new GnssMeasurement();
+}
+
+template <class T_IGnss>
+Return<sp<V2_1::IGnssConfiguration>> GnssTemplate<T_IGnss>::getExtensionGnssConfiguration_2_1() {
+    ALOGD("Gnss::getExtensionGnssConfiguration_2_1");
+    return mGnssConfiguration;
+}
+
+template <class T_IGnss>
+Return<sp<measurement_corrections::V1_1::IMeasurementCorrections>>
+GnssTemplate<T_IGnss>::getExtensionMeasurementCorrections_1_1() {
+    ALOGD("Gnss::getExtensionMeasurementCorrections_1_1()");
+    return new GnssMeasurementCorrections();
+}
+
+template <class T_IGnss>
+Return<sp<V2_1::IGnssAntennaInfo>> GnssTemplate<T_IGnss>::getExtensionGnssAntennaInfo() {
+    ALOGD("Gnss::getExtensionGnssAntennaInfo");
+    return new GnssAntennaInfo();
+}
+
+template <class T_IGnss>
+void GnssTemplate<T_IGnss>::reportSvStatus(const hidl_vec<GnssSvInfo>& svInfoList) const {
+    std::unique_lock<std::mutex> lock(mMutex);
+    // TODO(skz): update this to call 2_0 callback if non-null
+    if (sGnssCallback_2_1 == nullptr) {
+        ALOGE("%s: sGnssCallback v2.1 is null.", __func__);
+        return;
+    }
+    auto ret = sGnssCallback_2_1->gnssSvStatusCb_2_1(svInfoList);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+}
+
+template <class T_IGnss>
+void GnssTemplate<T_IGnss>::reportLocation(const V1_0::GnssLocation& location) const {
+    std::unique_lock<std::mutex> lock(mMutex);
+    if (sGnssCallback_1_1 != nullptr) {
+        auto ret = sGnssCallback_1_1->gnssLocationCb(location);
+        if (!ret.isOk()) {
+            ALOGE("%s: Unable to invoke callback v1.1", __func__);
+        }
+        return;
+    }
+    if (sGnssCallback_1_0 == nullptr) {
+        ALOGE("%s: No non-null callback", __func__);
+        return;
+    }
+    auto ret = sGnssCallback_1_0->gnssLocationCb(location);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback v1.0", __func__);
+    }
+}
+
+template <class T_IGnss>
+void GnssTemplate<T_IGnss>::reportLocation(const V2_0::GnssLocation& location) const {
+    std::unique_lock<std::mutex> lock(mMutex);
+    if (sGnssCallback_2_1 != nullptr) {
+        auto ret = sGnssCallback_2_1->gnssLocationCb_2_0(location);
+        if (!ret.isOk()) {
+            ALOGE("%s: Unable to invoke callback v2.1", __func__);
+        }
+        return;
+    }
+    if (sGnssCallback_2_0 == nullptr) {
+        ALOGE("%s: No non-null callback", __func__);
+        return;
+    }
+    auto ret = sGnssCallback_2_0->gnssLocationCb_2_0(location);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback v2.0", __func__);
+    }
+}
+
+}  // namespace android::hardware::gnss::common::implementation
diff --git a/gnss/common/utils/default/v2_1/GnssAntennaInfo.cpp b/gnss/common/utils/default/v2_1/GnssAntennaInfo.cpp
new file mode 100644
index 0000000..962451c
--- /dev/null
+++ b/gnss/common/utils/default/v2_1/GnssAntennaInfo.cpp
@@ -0,0 +1,101 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "GnssAntennaInfo"
+
+#include "v2_1/GnssAntennaInfo.h"
+#include "Utils.h"
+
+#include <log/log.h>
+
+using ::android::hardware::gnss::common::Utils;
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+sp<IGnssAntennaInfoCallback> GnssAntennaInfo::sCallback = nullptr;
+
+GnssAntennaInfo::GnssAntennaInfo() : mMinIntervalMillis(1000) {}
+
+GnssAntennaInfo::~GnssAntennaInfo() {
+    stop();
+}
+
+// Methods from ::android::hardware::gnss::V2_1::IGnssAntennaInfo follow.
+Return<GnssAntennaInfo::GnssAntennaInfoStatus> GnssAntennaInfo::setCallback(
+        const sp<IGnssAntennaInfoCallback>& callback) {
+    ALOGD("setCallback");
+    std::unique_lock<std::mutex> lock(mMutex);
+    sCallback = callback;
+
+    if (mIsActive) {
+        ALOGW("GnssAntennaInfo callback already set. Resetting the callback...");
+        stop();
+    }
+    start();
+
+    return GnssAntennaInfoStatus::SUCCESS;
+}
+
+Return<void> GnssAntennaInfo::close() {
+    ALOGD("close");
+    stop();
+    std::unique_lock<std::mutex> lock(mMutex);
+    sCallback = nullptr;
+    return Void();
+}
+
+// Private methods
+void GnssAntennaInfo::start() {
+    ALOGD("start");
+    mIsActive = true;
+    mThread = std::thread([this]() {
+        while (mIsActive == true) {
+            if (sCallback != nullptr) {
+                auto antennaInfos = Utils::getMockAntennaInfos();
+                this->reportAntennaInfo(antennaInfos);
+            }
+
+            /** For mock implementation this is good. On real device, we should only report
+                antennaInfo at start and when there is a configuration change. **/
+            std::this_thread::sleep_for(std::chrono::milliseconds(mMinIntervalMillis));
+        }
+    });
+}
+
+void GnssAntennaInfo::stop() {
+    ALOGD("stop");
+    mIsActive = false;
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+}
+
+void GnssAntennaInfo::reportAntennaInfo(
+        const hidl_vec<IGnssAntennaInfoCallback::GnssAntennaInfo>& antennaInfo) const {
+    std::unique_lock<std::mutex> lock(mMutex);
+
+    if (sCallback == nullptr) {
+        ALOGE("%s: No non-null callback", __func__);
+        return;
+    }
+
+    auto ret = sCallback->gnssAntennaInfoCb(antennaInfo);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+}
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/v2_1/GnssConfiguration.cpp b/gnss/common/utils/default/v2_1/GnssConfiguration.cpp
new file mode 100644
index 0000000..8b30701
--- /dev/null
+++ b/gnss/common/utils/default/v2_1/GnssConfiguration.cpp
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2019 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 "GnssConfiguration"
+
+#include "v2_1/GnssConfiguration.h"
+#include <log/log.h>
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+// Methods from ::android::hardware::gnss::V1_0::IGnssConfiguration follow.
+Return<bool> GnssConfiguration::setSuplEs(bool enable) {
+    ALOGD("setSuplEs enable: %d", enable);
+    // Method deprecated in 2.0 and not expected to be called by the framework.
+    return false;
+}
+
+Return<bool> GnssConfiguration::setSuplVersion(uint32_t) {
+    return true;
+}
+
+Return<bool> GnssConfiguration::setSuplMode(hidl_bitfield<SuplMode>) {
+    return true;
+}
+
+Return<bool> GnssConfiguration::setGpsLock(hidl_bitfield<GpsLock> gpsLock) {
+    ALOGD("setGpsLock gpsLock: %hhu", static_cast<GpsLock>(gpsLock));
+    // Method deprecated in 2.0 and not expected to be called by the framework.
+    return false;
+}
+
+Return<bool> GnssConfiguration::setLppProfile(hidl_bitfield<LppProfile>) {
+    return true;
+}
+
+Return<bool> GnssConfiguration::setGlonassPositioningProtocol(hidl_bitfield<GlonassPosProtocol>) {
+    return true;
+}
+
+Return<bool> GnssConfiguration::setEmergencySuplPdn(bool) {
+    return true;
+}
+
+// Methods from ::android::hardware::gnss::V1_1::IGnssConfiguration follow.
+Return<bool> GnssConfiguration::setBlacklist(
+        const hidl_vec<V1_1::IGnssConfiguration::BlacklistedSource>&) {
+    // TODO (b/122463906): Reuse 1.1 implementation.
+    return bool{};
+}
+
+// Methods from ::android::hardware::gnss::V2_0::IGnssConfiguration follow.
+Return<bool> GnssConfiguration::setEsExtensionSec(uint32_t emergencyExtensionSeconds) {
+    ALOGD("setEsExtensionSec emergencyExtensionSeconds: %d", emergencyExtensionSeconds);
+    return true;
+}
+
+// Methods from ::android::hardware::gnss::V2_1::IGnssConfiguration follow.
+Return<bool> GnssConfiguration::setBlacklist_2_1(
+        const hidl_vec<V2_1::IGnssConfiguration::BlacklistedSource>& sourceList) {
+    std::unique_lock<std::recursive_mutex> lock(mMutex);
+    mBlacklistedConstellationSet.clear();
+    mBlacklistedSourceSet.clear();
+    for (auto source : sourceList) {
+        if (source.svid == 0) {
+            // Wildcard blacklist, i.e., blacklist entire constellation.
+            mBlacklistedConstellationSet.insert(source.constellation);
+        } else {
+            mBlacklistedSourceSet.insert(source);
+        }
+    }
+    return true;
+}
+
+Return<bool> GnssConfiguration::isBlacklistedV2_1(const GnssSvInfoV2_1& gnssSvInfo) const {
+    std::unique_lock<std::recursive_mutex> lock(mMutex);
+    if (mBlacklistedConstellationSet.find(gnssSvInfo.v2_0.constellation) !=
+        mBlacklistedConstellationSet.end()) {
+        return true;
+    }
+    BlacklistedSourceV2_1 source = {.constellation = gnssSvInfo.v2_0.constellation,
+                                    .svid = gnssSvInfo.v2_0.v1_0.svid};
+    return (mBlacklistedSourceSet.find(source) != mBlacklistedSourceSet.end());
+}
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/v2_1/GnssDebug.cpp b/gnss/common/utils/default/v2_1/GnssDebug.cpp
new file mode 100644
index 0000000..492b970
--- /dev/null
+++ b/gnss/common/utils/default/v2_1/GnssDebug.cpp
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2016 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 "GnssDebug"
+
+#include <log/log.h>
+
+#include "Constants.h"
+#include "v2_1/GnssDebug.h"
+
+using namespace ::android::hardware::gnss::common;
+
+namespace android::hardware::gnss::V1_1::implementation {
+
+// Methods from ::android::hardware::gnss::V1_0::IGnssDebug follow.
+Return<void> GnssDebug::getDebugData(V1_0::IGnssDebug::getDebugData_cb _hidl_cb) {
+    PositionDebug positionDebug = {
+            .valid = true,
+            .latitudeDegrees = kMockLatitudeDegrees,
+            .longitudeDegrees = kMockLongitudeDegrees,
+            .altitudeMeters = kMockAltitudeMeters,
+            .speedMetersPerSec = kMockSpeedMetersPerSec,
+            .bearingDegrees = kMockBearingDegrees,
+            .horizontalAccuracyMeters = kMockHorizontalAccuracyMeters,
+            .verticalAccuracyMeters = kMockVerticalAccuracyMeters,
+            .speedAccuracyMetersPerSecond = kMockSpeedAccuracyMetersPerSecond,
+            .bearingAccuracyDegrees = kMockBearingAccuracyDegrees,
+            .ageSeconds = 0.99};
+
+    TimeDebug timeDebug = {.timeEstimate = kMockTimestamp,
+                           .timeUncertaintyNs = 1000,
+                           .frequencyUncertaintyNsPerSec = 5.0e4};
+
+    DebugData data = {.position = positionDebug, .time = timeDebug};
+
+    _hidl_cb(data);
+
+    return Void();
+}
+
+}  // namespace android::hardware::gnss::V1_1::implementation
diff --git a/gnss/common/utils/default/v2_1/GnssMeasurement.cpp b/gnss/common/utils/default/v2_1/GnssMeasurement.cpp
new file mode 100644
index 0000000..7d3a002
--- /dev/null
+++ b/gnss/common/utils/default/v2_1/GnssMeasurement.cpp
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2019 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 "GnssMeasurement"
+
+#include "v2_1/GnssMeasurement.h"
+#include <log/log.h>
+#include "Utils.h"
+
+namespace android::hardware::gnss::V2_1::implementation {
+
+using common::Utils;
+
+sp<V2_1::IGnssMeasurementCallback> GnssMeasurement::sCallback_2_1 = nullptr;
+sp<V2_0::IGnssMeasurementCallback> GnssMeasurement::sCallback_2_0 = nullptr;
+
+GnssMeasurement::GnssMeasurement() : mMinIntervalMillis(1000) {}
+
+GnssMeasurement::~GnssMeasurement() {
+    stop();
+}
+
+// Methods from V1_0::IGnssMeasurement follow.
+Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> GnssMeasurement::setCallback(
+        const sp<V1_0::IGnssMeasurementCallback>&) {
+    // TODO implement
+    return V1_0::IGnssMeasurement::GnssMeasurementStatus{};
+}
+
+Return<void> GnssMeasurement::close() {
+    ALOGD("close");
+    stop();
+    std::unique_lock<std::mutex> lock(mMutex);
+    sCallback_2_1 = nullptr;
+    sCallback_2_0 = nullptr;
+    return Void();
+}
+
+// Methods from V1_1::IGnssMeasurement follow.
+Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> GnssMeasurement::setCallback_1_1(
+        const sp<V1_1::IGnssMeasurementCallback>&, bool) {
+    // TODO implement
+    return V1_0::IGnssMeasurement::GnssMeasurementStatus{};
+}
+
+// Methods from V2_0::IGnssMeasurement follow.
+Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> GnssMeasurement::setCallback_2_0(
+        const sp<V2_0::IGnssMeasurementCallback>& callback, bool) {
+    ALOGD("setCallback_2_0");
+    std::unique_lock<std::mutex> lock(mMutex);
+    sCallback_2_0 = callback;
+
+    if (mIsActive) {
+        ALOGW("GnssMeasurement callback already set. Resetting the callback...");
+        stop();
+    }
+    start();
+
+    return V1_0::IGnssMeasurement::GnssMeasurementStatus::SUCCESS;
+}
+
+// Methods from V2_1::IGnssMeasurement follow.
+Return<V1_0::IGnssMeasurement::GnssMeasurementStatus> GnssMeasurement::setCallback_2_1(
+        const sp<V2_1::IGnssMeasurementCallback>& callback, bool) {
+    ALOGD("setCallback_2_1");
+    std::unique_lock<std::mutex> lock(mMutex);
+    sCallback_2_1 = callback;
+
+    if (mIsActive) {
+        ALOGW("GnssMeasurement callback already set. Resetting the callback...");
+        stop();
+    }
+    start();
+
+    return V1_0::IGnssMeasurement::GnssMeasurementStatus::SUCCESS;
+}
+
+void GnssMeasurement::start() {
+    ALOGD("start");
+    mIsActive = true;
+    mThread = std::thread([this]() {
+        while (mIsActive == true) {
+            if (sCallback_2_1 != nullptr) {
+                auto measurement = Utils::getMockMeasurementV2_1();
+                this->reportMeasurement(measurement);
+            } else {
+                auto measurement = Utils::getMockMeasurementV2_0();
+                this->reportMeasurement(measurement);
+            }
+
+            std::this_thread::sleep_for(std::chrono::milliseconds(mMinIntervalMillis));
+        }
+    });
+}
+
+void GnssMeasurement::stop() {
+    ALOGD("stop");
+    mIsActive = false;
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+}
+
+void GnssMeasurement::reportMeasurement(const GnssDataV2_0& data) {
+    ALOGD("reportMeasurement()");
+    std::unique_lock<std::mutex> lock(mMutex);
+    if (sCallback_2_0 == nullptr) {
+        ALOGE("%s: GnssMeasurement::sCallback_2_0 is null.", __func__);
+        return;
+    }
+    auto ret = sCallback_2_0->gnssMeasurementCb_2_0(data);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+}
+
+void GnssMeasurement::reportMeasurement(const GnssDataV2_1& data) {
+    ALOGD("reportMeasurement()");
+    std::unique_lock<std::mutex> lock(mMutex);
+    if (sCallback_2_1 == nullptr) {
+        ALOGE("%s: GnssMeasurement::sCallback_2_1 is null.", __func__);
+        return;
+    }
+    auto ret = sCallback_2_1->gnssMeasurementCb_2_1(data);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+    }
+}
+
+}  // namespace android::hardware::gnss::V2_1::implementation
diff --git a/gnss/common/utils/default/v2_1/GnssMeasurementCorrections.cpp b/gnss/common/utils/default/v2_1/GnssMeasurementCorrections.cpp
new file mode 100644
index 0000000..9be7e23
--- /dev/null
+++ b/gnss/common/utils/default/v2_1/GnssMeasurementCorrections.cpp
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2019 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 "GnssMeasurementCorrections"
+
+#include "v2_1/GnssMeasurementCorrections.h"
+#include <log/log.h>
+
+namespace android::hardware::gnss::measurement_corrections::V1_1::implementation {
+
+GnssMeasurementCorrections::GnssMeasurementCorrections() {}
+
+GnssMeasurementCorrections::~GnssMeasurementCorrections() {}
+
+// Methods from V1_0::IMeasurementCorrections follow.
+Return<bool> GnssMeasurementCorrections::setCorrections(
+        const V1_0::MeasurementCorrections& corrections) {
+    ALOGD("setCorrections");
+    ALOGD("corrections = lat: %f, lng: %f, alt: %f, hUnc: %f, vUnc: %f, toa: %llu, "
+          "satCorrections.size: %d",
+          corrections.latitudeDegrees, corrections.longitudeDegrees, corrections.altitudeMeters,
+          corrections.horizontalPositionUncertaintyMeters,
+          corrections.verticalPositionUncertaintyMeters,
+          static_cast<unsigned long long>(corrections.toaGpsNanosecondsOfWeek),
+          static_cast<int>(corrections.satCorrections.size()));
+    for (auto singleSatCorrection : corrections.satCorrections) {
+        ALOGD("singleSatCorrection = flags: %d, constellation: %d, svid: %d, cfHz: %f, probLos: %f,"
+              " epl: %f, eplUnc: %f",
+              static_cast<int>(singleSatCorrection.singleSatCorrectionFlags),
+              static_cast<int>(singleSatCorrection.constellation),
+              static_cast<int>(singleSatCorrection.svid), singleSatCorrection.carrierFrequencyHz,
+              singleSatCorrection.probSatIsLos, singleSatCorrection.excessPathLengthMeters,
+              singleSatCorrection.excessPathLengthUncertaintyMeters);
+        ALOGD("reflecting plane = lat: %f, lng: %f, alt: %f, azm: %f",
+              singleSatCorrection.reflectingPlane.latitudeDegrees,
+              singleSatCorrection.reflectingPlane.longitudeDegrees,
+              singleSatCorrection.reflectingPlane.altitudeMeters,
+              singleSatCorrection.reflectingPlane.azimuthDegrees);
+    }
+
+    return true;
+}
+
+Return<bool> GnssMeasurementCorrections::setCallback(
+        const sp<V1_0::IMeasurementCorrectionsCallback>& callback) {
+    using Capabilities = V1_0::IMeasurementCorrectionsCallback::Capabilities;
+    auto ret =
+            callback->setCapabilitiesCb(Capabilities::LOS_SATS | Capabilities::EXCESS_PATH_LENGTH |
+                                        Capabilities::REFLECTING_PLANE);
+    if (!ret.isOk()) {
+        ALOGE("%s: Unable to invoke callback", __func__);
+        return false;
+    }
+    return true;
+}
+
+// Methods from V1_1::IMeasurementCorrections follow.
+Return<bool> GnssMeasurementCorrections::setCorrections_1_1(
+        const V1_1::MeasurementCorrections& corrections) {
+    ALOGD("setCorrections_1_1");
+    ALOGD("corrections = lat: %f, lng: %f, alt: %f, hUnc: %f, vUnc: %f, toa: %llu,"
+          "satCorrections.size: %d, hasEnvironmentBearing: %d, environmentBearingDeg: %f,"
+          "environmentBearingUncDeg: %f",
+          corrections.v1_0.latitudeDegrees, corrections.v1_0.longitudeDegrees,
+          corrections.v1_0.altitudeMeters, corrections.v1_0.horizontalPositionUncertaintyMeters,
+          corrections.v1_0.verticalPositionUncertaintyMeters,
+          static_cast<unsigned long long>(corrections.v1_0.toaGpsNanosecondsOfWeek),
+          static_cast<int>(corrections.v1_0.satCorrections.size()),
+          corrections.hasEnvironmentBearing, corrections.environmentBearingDegrees,
+          corrections.environmentBearingUncertaintyDegrees);
+    for (auto singleSatCorrection : corrections.satCorrections) {
+        ALOGD("singleSatCorrection = flags: %d, constellation: %d, svid: %d, cfHz: %f, probLos: %f,"
+              " epl: %f, eplUnc: %f",
+              static_cast<int>(singleSatCorrection.v1_0.singleSatCorrectionFlags),
+              static_cast<int>(singleSatCorrection.constellation),
+              static_cast<int>(singleSatCorrection.v1_0.svid),
+              singleSatCorrection.v1_0.carrierFrequencyHz, singleSatCorrection.v1_0.probSatIsLos,
+              singleSatCorrection.v1_0.excessPathLengthMeters,
+              singleSatCorrection.v1_0.excessPathLengthUncertaintyMeters);
+        ALOGD("reflecting plane = lat: %f, lng: %f, alt: %f, azm: %f",
+              singleSatCorrection.v1_0.reflectingPlane.latitudeDegrees,
+              singleSatCorrection.v1_0.reflectingPlane.longitudeDegrees,
+              singleSatCorrection.v1_0.reflectingPlane.altitudeMeters,
+              singleSatCorrection.v1_0.reflectingPlane.azimuthDegrees);
+    }
+
+    return true;
+}
+
+}  // namespace android::hardware::gnss::measurement_corrections::V1_1::implementation