diff --git a/Android.bp b/Android.bp
index 70e0574..f64968f 100644
--- a/Android.bp
+++ b/Android.bp
@@ -26,7 +26,7 @@
     ],
 
     header_libs: [
-        "libhidl_gtest_helpers",
+        "libhidl_gtest_helper",
     ],
 
     group_static_libs: true,
diff --git a/atrace/1.0/vts/functional/Android.bp b/atrace/1.0/vts/functional/Android.bp
index d3f4276..ae24968 100644
--- a/atrace/1.0/vts/functional/Android.bp
+++ b/atrace/1.0/vts/functional/Android.bp
@@ -19,5 +19,5 @@
     defaults: ["VtsHalTargetTestDefaults"],
     srcs: ["VtsHalAtraceV1_0TargetTest.cpp"],
     static_libs: ["android.hardware.atrace@1.0"],
-    test_suites: ["general-tests"],
+    test_suites: ["general-tests", "vts-core"],
 }
diff --git a/atrace/1.0/vts/functional/VtsHalAtraceV1_0TargetTest.cpp b/atrace/1.0/vts/functional/VtsHalAtraceV1_0TargetTest.cpp
index c62c2f0..2eaa03e 100644
--- a/atrace/1.0/vts/functional/VtsHalAtraceV1_0TargetTest.cpp
+++ b/atrace/1.0/vts/functional/VtsHalAtraceV1_0TargetTest.cpp
@@ -18,8 +18,9 @@
 
 #include <android/hardware/atrace/1.0/IAtraceDevice.h>
 
-#include <VtsHalHidlTargetTestBase.h>
-#include <VtsHalHidlTargetTestEnvBase.h>
+#include <gtest/gtest.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
 
 using ::android::sp;
 using ::android::hardware::hidl_string;
@@ -28,29 +29,13 @@
 using ::android::hardware::atrace::V1_0::IAtraceDevice;
 using ::android::hardware::atrace::V1_0::Status;
 
-// Test environment for Boot HIDL HAL.
-class AtraceHidlEnvironment : public ::testing::VtsHalHidlTargetTestEnvBase {
-   public:
-    // get the test environment singleton
-    static AtraceHidlEnvironment* Instance() {
-        static AtraceHidlEnvironment* instance = new AtraceHidlEnvironment;
-        return instance;
-    }
-
-    virtual void registerTestServices() override { registerTestService<IAtraceDevice>(); }
-
-   private:
-    AtraceHidlEnvironment() {}
-};
-
 /**
  * There is no expected behaviour that can be tested so these tests check the
  * HAL doesn't crash with different execution orders.
  */
-struct AtraceHidlTest : public ::testing::VtsHalHidlTargetTestBase {
+struct AtraceHidlTest : public ::testing::TestWithParam<std::string> {
     virtual void SetUp() override {
-        atrace = ::testing::VtsHalHidlTargetTestBase::getService<IAtraceDevice>(
-            AtraceHidlEnvironment::Instance()->getServiceName<IAtraceDevice>());
+        atrace = IAtraceDevice::getService(GetParam());
         ASSERT_NE(atrace, nullptr);
     }
 
@@ -82,13 +67,13 @@
 }
 
 /* list categories from vendors. */
-TEST_F(AtraceHidlTest, listCategories) {
+TEST_P(AtraceHidlTest, listCategories) {
     hidl_vec<hidl_string> vnd_categories = getVendorCategoryName(atrace);
     EXPECT_NE(0, vnd_categories.size());
 }
 
 /* enable categories. */
-TEST_F(AtraceHidlTest, enableCategories) {
+TEST_P(AtraceHidlTest, enableCategories) {
     hidl_vec<hidl_string> vnd_categories = getVendorCategoryName(atrace);
     // empty Category with ERROR_INVALID_ARGUMENT
     hidl_vec<hidl_string> empty_categories;
@@ -102,17 +87,13 @@
 }
 
 /* enable categories. */
-TEST_F(AtraceHidlTest, disableAllCategories) {
+TEST_P(AtraceHidlTest, disableAllCategories) {
     auto ret = atrace->disableAllCategories();
     ASSERT_TRUE(ret.isOk());
     EXPECT_EQ(Status::SUCCESS, ret);
 }
 
-int main(int argc, char** argv) {
-    ::testing::AddGlobalTestEnvironment(AtraceHidlEnvironment::Instance());
-    ::testing::InitGoogleTest(&argc, argv);
-    AtraceHidlEnvironment::Instance()->init(&argc, argv);
-    int status = RUN_ALL_TESTS();
-    ALOGI("Test result = %d", status);
-    return status;
-}
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, AtraceHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IAtraceDevice::descriptor)),
+        android::hardware::PrintInstanceNameToString);
diff --git a/current.txt b/current.txt
index 3ccc531..e22db18 100644
--- a/current.txt
+++ b/current.txt
@@ -587,6 +587,9 @@
 # HALs released in Android R
 07d0a252b2d8fa35887908a996ba395cf392968395fc30afab791f46e0c22a52 android.hardware.boot@1.1::IBootControl
 74049a402be913963edfdd80828a53736570e9d8124a1bf18166b6ed46a6b0ab android.hardware.boot@1.1::types
+ce8dbe76eb9ee94b46ef98f725be992e760a5751073d4f4912484026541371f3 android.hardware.health@2.1::IHealth
+26f04510a0b57aba5167c5c0a7c2f077c2acbb98b81902a072517829fd9fd67f android.hardware.health@2.1::IHealthInfoCallback
+db47f4ceceb1f06c656f39caa70c557b0f8471ef59fd58611bea667ffca20101 android.hardware.health@2.1::types
 34515afa2bb792d3c6d8495a5f5d907d179c8507ca5e55c10050d02ae1d516ef android.hardware.neuralnetworks@1.3::IDevice
 b74fe72cfe438f50e772e6a307657ff449d5bde83c15dd1f140ff2edbe73499c android.hardware.neuralnetworks@1.3::types
 544049dcda3f943ad67d83d5277f06681a3782982a9af5a78b5d4e8d295d061a android.hardware.vibrator@1.4::IVibrator
diff --git a/graphics/composer/2.1/utils/vts/include/composer-vts/2.1/ComposerVts.h b/graphics/composer/2.1/utils/vts/include/composer-vts/2.1/ComposerVts.h
index 4294657..63aa713 100644
--- a/graphics/composer/2.1/utils/vts/include/composer-vts/2.1/ComposerVts.h
+++ b/graphics/composer/2.1/utils/vts/include/composer-vts/2.1/ComposerVts.h
@@ -57,6 +57,7 @@
    public:
     Composer();
     explicit Composer(const std::string& name);
+    explicit Composer(const sp<IComposer>& composer);
 
     sp<IComposer> getRaw() const;
 
@@ -67,9 +68,6 @@
     std::string dumpDebugInfo();
     std::unique_ptr<ComposerClient> createClient();
 
-   protected:
-    explicit Composer(const sp<IComposer>& composer);
-
    private:
     const sp<IComposer> mComposer;
 
diff --git a/graphics/composer/2.1/vts/functional/Android.bp b/graphics/composer/2.1/vts/functional/Android.bp
index 799ca91..5f1ed63 100644
--- a/graphics/composer/2.1/vts/functional/Android.bp
+++ b/graphics/composer/2.1/vts/functional/Android.bp
@@ -42,5 +42,6 @@
     header_libs: [
         "android.hardware.graphics.composer@2.1-command-buffer",
     ],
-    test_suites: ["general-tests"],
+    disable_framework: true,
+    test_suites: ["general-tests", "vts-core"],
 }
diff --git a/graphics/composer/2.1/vts/functional/VtsHalGraphicsComposerV2_1TargetTest.cpp b/graphics/composer/2.1/vts/functional/VtsHalGraphicsComposerV2_1TargetTest.cpp
index 9477ee6..b92279d 100644
--- a/graphics/composer/2.1/vts/functional/VtsHalGraphicsComposerV2_1TargetTest.cpp
+++ b/graphics/composer/2.1/vts/functional/VtsHalGraphicsComposerV2_1TargetTest.cpp
@@ -20,13 +20,14 @@
 #include <composer-vts/2.1/ComposerVts.h>
 #include <composer-vts/2.1/GraphicsComposerCallback.h>
 #include <composer-vts/2.1/TestCommandReader.h>
+#include <gtest/gtest.h>
 #include <hardware/hwcomposer2.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
 #include <mapper-vts/2.0/MapperVts.h>
 #include <mapper-vts/3.0/MapperVts.h>
 #include <mapper-vts/4.0/MapperVts.h>
 
-#include <VtsHalHidlTargetTestBase.h>
-#include <VtsHalHidlTargetTestEnvBase.h>
 #include <unistd.h>
 
 #include <algorithm>
@@ -52,30 +53,11 @@
 using android::hardware::graphics::common::V1_0::Transform;
 using GrallocError = android::hardware::graphics::mapper::V2_0::Error;
 
-// Test environment for graphics.composer
-class GraphicsComposerHidlEnvironment : public ::testing::VtsHalHidlTargetTestEnvBase {
-   public:
-    // get the test environment singleton
-    static GraphicsComposerHidlEnvironment* Instance() {
-        static GraphicsComposerHidlEnvironment* instance = new GraphicsComposerHidlEnvironment;
-        return instance;
-    }
-
-    virtual void registerTestServices() override { registerTestService<IComposer>(); }
-
-   private:
-    GraphicsComposerHidlEnvironment() {}
-
-    GTEST_DISALLOW_COPY_AND_ASSIGN_(GraphicsComposerHidlEnvironment);
-};
-
-class GraphicsComposerHidlTest : public ::testing::VtsHalHidlTargetTestBase {
-   protected:
+class GraphicsComposerHidlTest : public ::testing::TestWithParam<std::string> {
+  protected:
     void SetUp() override {
-        VtsHalHidlTargetTestBase::SetUp();
         ASSERT_NO_FATAL_FAILURE(
-            mComposer = std::make_unique<Composer>(
-                GraphicsComposerHidlEnvironment::Instance()->getServiceName<IComposer>()));
+                mComposer = std::make_unique<Composer>(IComposer::getService(GetParam())));
         ASSERT_NO_FATAL_FAILURE(mComposerClient = mComposer->createClient());
 
         mComposerCallback = new GraphicsComposerCallback;
@@ -102,7 +84,6 @@
             EXPECT_EQ(0, mComposerCallback->getInvalidRefreshCount());
             EXPECT_EQ(0, mComposerCallback->getInvalidVsyncCount());
         }
-        VtsHalHidlTargetTestBase::TearDown();
     }
 
     // returns an invalid display id (one that has not been registered to a
@@ -151,7 +132,7 @@
  *
  * Test that IComposer::getCapabilities returns no invalid capabilities.
  */
-TEST_F(GraphicsComposerHidlTest, GetCapabilities) {
+TEST_P(GraphicsComposerHidlTest, GetCapabilities) {
     auto capabilities = mComposer->getCapabilities();
     ASSERT_EQ(capabilities.end(),
               std::find(capabilities.begin(), capabilities.end(), IComposer::Capability::INVALID));
@@ -160,7 +141,7 @@
 /**
  * Test IComposer::dumpDebugInfo.
  */
-TEST_F(GraphicsComposerHidlTest, DumpDebugInfo) {
+TEST_P(GraphicsComposerHidlTest, DumpDebugInfo) {
     mComposer->dumpDebugInfo();
 }
 
@@ -169,7 +150,7 @@
  *
  * Test that IComposerClient is a singleton.
  */
-TEST_F(GraphicsComposerHidlTest, CreateClientSingleton) {
+TEST_P(GraphicsComposerHidlTest, CreateClientSingleton) {
     mComposer->getRaw()->createClient(
         [&](const auto& tmpError, const auto&) { EXPECT_EQ(Error::NO_RESOURCES, tmpError); });
 }
@@ -180,7 +161,7 @@
  *
  * Test that virtual displays can be created and has the correct display type.
  */
-TEST_F(GraphicsComposerHidlTest, CreateVirtualDisplay) {
+TEST_P(GraphicsComposerHidlTest, CreateVirtualDisplay) {
     if (mComposerClient->getMaxVirtualDisplayCount() == 0) {
         GTEST_SUCCEED() << "no virtual display support";
         return;
@@ -205,7 +186,7 @@
  * Test that passing a bad display handle to destroyVirtualDisplay
  * returns a BAD_DISPLAY error
  */
-TEST_F(GraphicsComposerHidlTest, DestroyVirtualDisplayBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, DestroyVirtualDisplayBadDisplay) {
     if (mComposerClient->getMaxVirtualDisplayCount() == 0) {
         GTEST_SUCCEED() << "no virtual display support";
         return;
@@ -220,7 +201,7 @@
  *
  * Test that layers can be created and destroyed.
  */
-TEST_F(GraphicsComposerHidlTest, CreateLayer) {
+TEST_P(GraphicsComposerHidlTest, CreateLayer) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -234,7 +215,7 @@
  * Test that passing in an invalid display handle to createLayer returns
  * BAD_DISPLAY.
  */
-TEST_F(GraphicsComposerHidlTest, CreateLayerBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, CreateLayerBadDisplay) {
     Error error;
     mComposerClient->getRaw()->createLayer(
         mInvalidDisplayId, kBufferSlotCount,
@@ -248,7 +229,7 @@
  * Test that passing in an invalid display handle to destroyLayer returns
  * BAD_DISPLAY
  */
-TEST_F(GraphicsComposerHidlTest, DestroyLayerBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, DestroyLayerBadDisplay) {
     Error error;
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
@@ -267,7 +248,7 @@
  * Test that passing in an invalid layer handle to destroyLayer returns
  * BAD_LAYER
  */
-TEST_F(GraphicsComposerHidlTest, DestroyLayerBadLayerError) {
+TEST_P(GraphicsComposerHidlTest, DestroyLayerBadLayerError) {
     // We haven't created any layers yet, so any id should be invalid
     Error error = mComposerClient->getRaw()->destroyLayer(mPrimaryDisplay, 1);
 
@@ -280,7 +261,7 @@
  * Test that passing in a bad display handle to getActiveConfig generates a
  * BAD_DISPLAY error
  */
-TEST_F(GraphicsComposerHidlTest, GetActiveConfigBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, GetActiveConfigBadDisplay) {
     Error error;
     mComposerClient->getRaw()->getActiveConfig(
         mInvalidDisplayId, [&](const auto& tmpOutError, const auto&) { error = tmpOutError; });
@@ -293,7 +274,7 @@
  * Test IComposerClient::getDisplayConfigs returns no error
  * when passed in a valid display
  */
-TEST_F(GraphicsComposerHidlTest, GetDisplayConfig) {
+TEST_P(GraphicsComposerHidlTest, GetDisplayConfig) {
     std::vector<Config> configs;
     ASSERT_NO_FATAL_FAILURE(configs = mComposerClient->getDisplayConfigs(mPrimaryDisplay));
 }
@@ -304,7 +285,7 @@
  * Test IComposerClient::getDisplayConfigs returns BAD_DISPLAY
  * when passed in an invalid display handle
  */
-TEST_F(GraphicsComposerHidlTest, GetDisplayConfigBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, GetDisplayConfigBadDisplay) {
     Error error;
     mComposerClient->getRaw()->getDisplayConfigs(
         mInvalidDisplayId, [&](const auto& tmpOutError, const auto&) { error = tmpOutError; });
@@ -314,7 +295,7 @@
 /**
  * Test IComposerClient::getDisplayName.
  */
-TEST_F(GraphicsComposerHidlTest, GetDisplayName) {
+TEST_P(GraphicsComposerHidlTest, GetDisplayName) {
     mComposerClient->getDisplayName(mPrimaryDisplay);
 }
 
@@ -324,7 +305,7 @@
  * Test that IComposerClient::getDisplayType returns the correct display type
  * for the primary display.
  */
-TEST_F(GraphicsComposerHidlTest, GetDisplayType) {
+TEST_P(GraphicsComposerHidlTest, GetDisplayType) {
     ASSERT_EQ(IComposerClient::DisplayType::PHYSICAL,
               mComposerClient->getDisplayType(mPrimaryDisplay));
 }
@@ -335,7 +316,7 @@
  * Test that IComposerClient::getClientTargetSupport returns true for the
  * required client targets.
  */
-TEST_F(GraphicsComposerHidlTest, GetClientTargetSupport) {
+TEST_P(GraphicsComposerHidlTest, GetClientTargetSupport) {
     std::vector<Config> configs = mComposerClient->getDisplayConfigs(mPrimaryDisplay);
     for (auto config : configs) {
         int32_t width = mComposerClient->getDisplayAttribute(mPrimaryDisplay, config,
@@ -358,7 +339,7 @@
  * Test that IComposerClient::getClientTargetSupport returns BAD_DISPLAY when
  * passed an invalid display handle
  */
-TEST_F(GraphicsComposerHidlTest, GetClientTargetSupportBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, GetClientTargetSupportBadDisplay) {
     std::vector<Config> configs = mComposerClient->getDisplayConfigs(mPrimaryDisplay);
     for (auto config : configs) {
         int32_t width = mComposerClient->getDisplayAttribute(mPrimaryDisplay, config,
@@ -382,7 +363,7 @@
  * Test that IComposerClient::getDisplayAttribute succeeds for the required
  * formats, and succeeds or fails correctly for optional attributes.
  */
-TEST_F(GraphicsComposerHidlTest, GetDisplayAttribute) {
+TEST_P(GraphicsComposerHidlTest, GetDisplayAttribute) {
     std::vector<Config> configs = mComposerClient->getDisplayConfigs(mPrimaryDisplay);
     for (auto config : configs) {
         const std::array<IComposerClient::Attribute, 3> requiredAttributes = {{
@@ -408,7 +389,7 @@
 /**
  * Test IComposerClient::getHdrCapabilities.
  */
-TEST_F(GraphicsComposerHidlTest, GetHdrCapabilities) {
+TEST_P(GraphicsComposerHidlTest, GetHdrCapabilities) {
     float maxLuminance;
     float maxAverageLuminance;
     float minLuminance;
@@ -419,7 +400,7 @@
 /**
  * Test IComposerClient::setClientTargetSlotCount.
  */
-TEST_F(GraphicsComposerHidlTest, SetClientTargetSlotCount) {
+TEST_P(GraphicsComposerHidlTest, SetClientTargetSlotCount) {
     mComposerClient->setClientTargetSlotCount(mPrimaryDisplay, kBufferSlotCount);
 }
 
@@ -429,7 +410,7 @@
  * Test that IComposerClient::setActiveConfig succeeds for all display
  * configs.
  */
-TEST_F(GraphicsComposerHidlTest, SetActiveConfig) {
+TEST_P(GraphicsComposerHidlTest, SetActiveConfig) {
     std::vector<Config> configs = mComposerClient->getDisplayConfigs(mPrimaryDisplay);
     for (auto config : configs) {
         mComposerClient->setActiveConfig(mPrimaryDisplay, config);
@@ -443,7 +424,7 @@
  * Test that config set during IComposerClient::setActiveConfig is maintained
  * during a display on/off power cycle
  */
-TEST_F(GraphicsComposerHidlTest, SetActiveConfigPowerCycle) {
+TEST_P(GraphicsComposerHidlTest, SetActiveConfigPowerCycle) {
     ASSERT_NO_FATAL_FAILURE(
         mComposerClient->setPowerMode(mPrimaryDisplay, IComposerClient::PowerMode::OFF));
     ASSERT_NO_FATAL_FAILURE(
@@ -467,7 +448,7 @@
  *
  * Test that IComposerClient::getColorMode always returns ColorMode::NATIVE
  */
-TEST_F(GraphicsComposerHidlTest, GetColorModes) {
+TEST_P(GraphicsComposerHidlTest, GetColorModes) {
     std::vector<ColorMode> modes = mComposerClient->getColorModes(mPrimaryDisplay);
     auto nativeModeLocation = std::find(modes.begin(), modes.end(), ColorMode::NATIVE);
 
@@ -479,7 +460,7 @@
  *
  * Test that IComposerClient::setColorMode succeeds for all color modes.
  */
-TEST_F(GraphicsComposerHidlTest, SetColorMode) {
+TEST_P(GraphicsComposerHidlTest, SetColorMode) {
     std::unordered_set<ColorMode> validModes;
     for (auto mode : hidl_enum_range<ColorMode>()) {
         validModes.insert(mode);
@@ -499,7 +480,7 @@
  * Test that IComposerClient::setColorMode returns BAD_DISPLAY for
  * an invalid display handle
  */
-TEST_F(GraphicsComposerHidlTest, SetColorModeBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, SetColorModeBadDisplay) {
     std::vector<ColorMode> modes = mComposerClient->getColorModes(mPrimaryDisplay);
     for (auto mode : modes) {
         Error error = mComposerClient->getRaw()->setColorMode(mInvalidDisplayId, mode);
@@ -513,7 +494,7 @@
  * Test that IComposerClient::setColorMode returns BAD_PARAMETER when passed in
  * an invalid color mode
  */
-TEST_F(GraphicsComposerHidlTest, SetColorModeBadParameter) {
+TEST_P(GraphicsComposerHidlTest, SetColorModeBadParameter) {
     Error error =
         mComposerClient->getRaw()->setColorMode(mPrimaryDisplay, static_cast<ColorMode>(-1));
     ASSERT_EQ(Error::BAD_PARAMETER, error);
@@ -525,7 +506,7 @@
  * Test that IComposerClient::getDozeSupport returns
  * BAD_DISPLAY when passed an invalid display handle
  */
-TEST_F(GraphicsComposerHidlTest, GetDozeSupportBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, GetDozeSupportBadDisplay) {
     Error error;
     mComposerClient->getRaw()->getDozeSupport(
         mInvalidDisplayId, [&](const auto& tmpOutError, const auto&) { error = tmpOutError; });
@@ -537,7 +518,7 @@
  *
  * Test that IComposerClient::setPowerMode succeeds for all power modes.
  */
-TEST_F(GraphicsComposerHidlTest, SetPowerMode) {
+TEST_P(GraphicsComposerHidlTest, SetPowerMode) {
     std::vector<IComposerClient::PowerMode> modes;
     modes.push_back(IComposerClient::PowerMode::OFF);
 
@@ -560,7 +541,7 @@
  * Test IComposerClient::setPowerMode succeeds with different
  * orderings of power modes
  */
-TEST_F(GraphicsComposerHidlTest, SetPowerModeVariations) {
+TEST_P(GraphicsComposerHidlTest, SetPowerModeVariations) {
     std::vector<IComposerClient::PowerMode> modes;
     modes.push_back(IComposerClient::PowerMode::OFF);
     modes.push_back(IComposerClient::PowerMode::ON);
@@ -611,7 +592,7 @@
  * Test IComposerClient::setPowerMode returns BAD_DISPLAY when passed an invalid
  * display handle
  */
-TEST_F(GraphicsComposerHidlTest, SetPowerModeBadDisplay) {
+TEST_P(GraphicsComposerHidlTest, SetPowerModeBadDisplay) {
     Error error =
         mComposerClient->getRaw()->setPowerMode(mInvalidDisplayId, IComposerClient::PowerMode::ON);
     ASSERT_EQ(Error::BAD_DISPLAY, error);
@@ -623,7 +604,7 @@
  * Test that IComposerClient::setPowerMode returns UNSUPPORTED when passed DOZE
  * or DOZE_SUSPEND on devices that do not support DOZE/DOZE_SUSPEND
  */
-TEST_F(GraphicsComposerHidlTest, SetPowerModeUnsupported) {
+TEST_P(GraphicsComposerHidlTest, SetPowerModeUnsupported) {
     if (!mComposerClient->getDozeSupport(mPrimaryDisplay)) {
         Error error = mComposerClient->getRaw()->setPowerMode(mPrimaryDisplay,
                                                               IComposerClient::PowerMode::DOZE);
@@ -641,7 +622,7 @@
  * Tests that IComposerClient::setPowerMode returns BAD_PARAMETER when passed an invalid
  * PowerMode
  */
-TEST_F(GraphicsComposerHidlTest, SetPowerModeBadParameter) {
+TEST_P(GraphicsComposerHidlTest, SetPowerModeBadParameter) {
     Error error = mComposerClient->getRaw()->setPowerMode(
         mPrimaryDisplay, static_cast<IComposerClient::PowerMode>(-1));
     ASSERT_EQ(Error::BAD_PARAMETER, error);
@@ -653,7 +634,7 @@
  * Test that IComposerClient::setVsyncEnabled succeeds and there is no
  * spurious vsync events.
  */
-TEST_F(GraphicsComposerHidlTest, SetVsyncEnabled) {
+TEST_P(GraphicsComposerHidlTest, SetVsyncEnabled) {
     mComposerCallback->setVsyncAllowed(true);
 
     mComposerClient->setVsyncEnabled(mPrimaryDisplay, true);
@@ -705,7 +686,7 @@
 /**
  * Test IComposerClient::Command::SET_COLOR_TRANSFORM.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_COLOR_TRANSFORM) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_COLOR_TRANSFORM) {
     const std::array<float, 16> identity = {{
         1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
         1.0f,
@@ -720,7 +701,7 @@
 /**
  * Test IComposerClient::Command::SET_CLIENT_TARGET.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_CLIENT_TARGET) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_CLIENT_TARGET) {
     mComposerClient->setClientTargetSlotCount(mPrimaryDisplay, kBufferSlotCount);
 
     mWriter->selectDisplay(mPrimaryDisplay);
@@ -733,7 +714,7 @@
 /**
  * Test IComposerClient::Command::SET_OUTPUT_BUFFER.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_OUTPUT_BUFFER) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_OUTPUT_BUFFER) {
     if (mComposerClient->getMaxVirtualDisplayCount() == 0) {
         GTEST_SUCCEED() << "no virtual display support";
         return;
@@ -756,7 +737,7 @@
 /**
  * Test IComposerClient::Command::VALIDATE_DISPLAY.
  */
-TEST_F(GraphicsComposerHidlCommandTest, VALIDATE_DISPLAY) {
+TEST_P(GraphicsComposerHidlCommandTest, VALIDATE_DISPLAY) {
     mWriter->selectDisplay(mPrimaryDisplay);
     mWriter->validateDisplay();
     execute();
@@ -765,7 +746,7 @@
 /**
  * Test IComposerClient::Command::ACCEPT_DISPLAY_CHANGES.
  */
-TEST_F(GraphicsComposerHidlCommandTest, ACCEPT_DISPLAY_CHANGES) {
+TEST_P(GraphicsComposerHidlCommandTest, ACCEPT_DISPLAY_CHANGES) {
     mWriter->selectDisplay(mPrimaryDisplay);
     mWriter->validateDisplay();
     mWriter->acceptDisplayChanges();
@@ -775,7 +756,7 @@
 /**
  * Test IComposerClient::Command::PRESENT_DISPLAY.
  */
-TEST_F(GraphicsComposerHidlCommandTest, PRESENT_DISPLAY) {
+TEST_P(GraphicsComposerHidlCommandTest, PRESENT_DISPLAY) {
     mWriter->selectDisplay(mPrimaryDisplay);
     mWriter->validateDisplay();
     mWriter->presentDisplay();
@@ -789,7 +770,7 @@
  * additional call to validateDisplay when only the layer buffer handle and
  * surface damage have been set
  */
-TEST_F(GraphicsComposerHidlCommandTest, PRESENT_DISPLAY_NO_LAYER_STATE_CHANGES) {
+TEST_P(GraphicsComposerHidlCommandTest, PRESENT_DISPLAY_NO_LAYER_STATE_CHANGES) {
     if (!mComposer->hasCapability(
                 static_cast<IComposer::Capability>(HWC2_CAPABILITY_SKIP_VALIDATE))) {
         std::cout << "Device does not have skip validate capability, skipping" << std::endl;
@@ -845,7 +826,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_CURSOR_POSITION.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_CURSOR_POSITION) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_CURSOR_POSITION) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -887,7 +868,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_BUFFER.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_BUFFER) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_BUFFER) {
     auto handle = allocate();
     ASSERT_NE(nullptr, handle);
 
@@ -904,7 +885,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_SURFACE_DAMAGE.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_SURFACE_DAMAGE) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_SURFACE_DAMAGE) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -923,7 +904,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_BLEND_MODE.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_BLEND_MODE) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_BLEND_MODE) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -939,7 +920,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_COLOR.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_COLOR) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_COLOR) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -954,7 +935,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_COMPOSITION_TYPE.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_COMPOSITION_TYPE) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_COMPOSITION_TYPE) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -971,7 +952,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_DATASPACE.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_DATASPACE) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_DATASPACE) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -985,7 +966,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_DISPLAY_FRAME.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_DISPLAY_FRAME) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_DISPLAY_FRAME) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -999,7 +980,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_PLANE_ALPHA.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_PLANE_ALPHA) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_PLANE_ALPHA) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -1014,7 +995,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_SIDEBAND_STREAM.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_SIDEBAND_STREAM) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_SIDEBAND_STREAM) {
     if (!mComposer->hasCapability(IComposer::Capability::SIDEBAND_STREAM)) {
         GTEST_SUCCEED() << "no sideband stream support";
         return;
@@ -1036,7 +1017,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_SOURCE_CROP.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_SOURCE_CROP) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_SOURCE_CROP) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -1050,7 +1031,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_TRANSFORM.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_TRANSFORM) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_TRANSFORM) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -1071,7 +1052,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_VISIBLE_REGION.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_VISIBLE_REGION) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_VISIBLE_REGION) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -1090,7 +1071,7 @@
 /**
  * Test IComposerClient::Command::SET_LAYER_Z_ORDER.
  */
-TEST_F(GraphicsComposerHidlCommandTest, SET_LAYER_Z_ORDER) {
+TEST_P(GraphicsComposerHidlCommandTest, SET_LAYER_Z_ORDER) {
     Layer layer;
     ASSERT_NO_FATAL_FAILURE(layer =
                                 mComposerClient->createLayer(mPrimaryDisplay, kBufferSlotCount));
@@ -1102,6 +1083,16 @@
     execute();
 }
 
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, GraphicsComposerHidlCommandTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IComposer::descriptor)),
+        android::hardware::PrintInstanceNameToString);
+
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, GraphicsComposerHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IComposer::descriptor)),
+        android::hardware::PrintInstanceNameToString);
+
 }  // namespace
 }  // namespace vts
 }  // namespace V2_1
@@ -1109,13 +1100,3 @@
 }  // namespace graphics
 }  // namespace hardware
 }  // namespace android
-
-int main(int argc, char** argv) {
-    using android::hardware::graphics::composer::V2_1::vts::GraphicsComposerHidlEnvironment;
-    ::testing::AddGlobalTestEnvironment(GraphicsComposerHidlEnvironment::Instance());
-    ::testing::InitGoogleTest(&argc, argv);
-    GraphicsComposerHidlEnvironment::Instance()->init(&argc, argv);
-    int status = RUN_ALL_TESTS();
-    ALOGI("Test result = %d", status);
-    return status;
-}
diff --git a/graphics/composer/2.4/Android.bp b/graphics/composer/2.4/Android.bp
index 0e1bc09..5f700be 100644
--- a/graphics/composer/2.4/Android.bp
+++ b/graphics/composer/2.4/Android.bp
@@ -7,7 +7,9 @@
         enabled: true,
     },
     srcs: [
+        "types.hal",
         "IComposer.hal",
+        "IComposerCallback.hal",
         "IComposerClient.hal",
     ],
     interfaces: [
diff --git a/graphics/composer/2.4/IComposerCallback.hal b/graphics/composer/2.4/IComposerCallback.hal
new file mode 100644
index 0000000..5c3f8bd
--- /dev/null
+++ b/graphics/composer/2.4/IComposerCallback.hal
@@ -0,0 +1,35 @@
+/*
+ * Copyright 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.
+ */
+
+package android.hardware.graphics.composer@2.4;
+
+import @2.1::Display;
+import @2.1::IComposerCallback;
+
+interface IComposerCallback extends @2.1::IComposerCallback {
+    /**
+     * Notifies the client that a vsync event has occurred. This callback must
+     * only be triggered when vsync is enabled for this display (through
+     * setVsyncEnabled).
+     *
+     * @param display is the display which has received a vsync event
+     * @param timestamp is the CLOCK_MONOTONIC time at which the vsync event
+     *        occurred, in nanoseconds.
+     * @param vsyncPeriodNanos is the display vsync period in nanoseconds i.e. the next onVsync_2_4
+     *        is expected to be called vsyncPeriodNanos nanoseconds after this call.
+     */
+    oneway onVsync_2_4(Display display, int64_t timestamp, VsyncPeriodNanos vsyncPeriodNanos);
+};
diff --git a/graphics/composer/2.4/IComposerClient.hal b/graphics/composer/2.4/IComposerClient.hal
index 60445f5..c2102d5 100644
--- a/graphics/composer/2.4/IComposerClient.hal
+++ b/graphics/composer/2.4/IComposerClient.hal
@@ -16,6 +16,8 @@
 
 package android.hardware.graphics.composer@2.4;
 
+import IComposerCallback;
+import @2.1::Config;
 import @2.1::Display;
 import @2.1::Error;
 import @2.3::IComposerClient;
@@ -50,6 +52,32 @@
     };
 
     /**
+     * Constraints for changing vsync period.
+     */
+    struct VsyncPeriodChangeConstraints {
+        /**
+         * Time in CLOCK_MONOTONIC after which the vsync period may change
+         * (i.e., the vsync period must not change before this time).
+         */
+        int64_t desiredTimeNanos;
+        /**
+         * If true, requires that the vsync period change must happen seamlessly without
+         * a noticeable visual artifact.
+         */
+        bool seamlessRequired;
+    };
+
+    /**
+     * Provides a IComposerCallback object for the device to call.
+     *
+     * This function must be called only once.
+     *
+     * @param callback is the IComposerCallback object.
+     */
+    @entry
+    registerCallback_2_4(IComposerCallback callback);
+
+    /**
      * Provides a list of supported capabilities (as described in the
      * definition of DisplayCapability above). This list must not change after
      * initialization.
@@ -69,4 +97,63 @@
      * @return type is the connection type of the display.
      */
     getDisplayConnectionType(Display display) generates (Error error, DisplayConnectionType type);
+
+    /**
+     * Provides a list of the vsync periods supported by the display in the given configuration
+     *
+     * @param display is the display for which the vsync periods are queried.
+     * @param config is the display configuration for which the vsync periods are queried.
+     *
+     * @return error is NONE upon success. Otherwise,
+     *     BAD_DISPLAY when an invalid display handle was passed in.
+     *     BAD_CONFIG when an invalid config handle was passed in.
+     * @return supportedVsyncPeriods is a list of supported vsync periods.
+     */
+    getSupportedDisplayVsyncPeriods(Display display, Config config)
+        generates (Error error, vec<VsyncPeriodNanos> supportedVsyncPeriods);
+
+    /**
+     * Retrieves which vsync period the display is currently using.
+     *
+     * If no display configuration is currently active, this function must
+     * return BAD_CONFIG. If the vsync period is about to change due to a
+     * setActiveConfigAndVsyncPeriod call, this function must return the current vsync period
+     * until the change takes place.
+     *
+     * @param display is the display for which the vsync period is queried.
+     * @return error is NONE upon success. Otherwise,
+     *         BAD_DISPLAY when an invalid display handle was passed in.
+     *         BAD_CONFIG when no configuration is currently active.
+     * @return vsyncPeriodNanos is the current vsync period of the display.
+     */
+    getDisplayVsyncPeriod(Display display)
+        generates (Error error, VsyncPeriodNanos vsyncPeriodNanos);
+
+    /**
+     * Sets the active configuration and the refresh rate for this display.
+     * If the config is the same as the current config, only the vsync period shall change.
+     * Upon returning, the given display configuration, except vsync period, must be active and
+     * remain so until either this function is called again or the display is disconnected.
+     * When the display starts to refresh at the new vsync period, onVsync_2_4 callback must be
+     * called with the new vsync period.
+     *
+     * @param display is the display for which the active config is set.
+     * @param config is the new display configuration.
+     * @param vsyncPeriodNanos is the new display vsync period.
+     * @param vsyncPeriodChangeConstraints are the constraints required for changing vsync period.
+     *
+     * @return error is NONE upon success. Otherwise,
+     *         BAD_DISPLAY when an invalid display handle was passed in.
+     *         BAD_CONFIG when the configuration handle passed in is not valid
+     *                    for this display.
+     *         BAD_VSYNC_PERIOD when an invalid vsync period is passed in.
+     *         SEAMLESS_NOT_POSSIBLE when seamlessRequired was true but the display cannot achieve
+     *                               the vsync period change without a noticeable visual artifact.
+     * @return newVsyncAppliedTime is the time in CLOCK_MONOTONIC when the new display will start to
+     *                             refresh at the new vsync period.
+     */
+    setActiveConfigAndVsyncPeriod(Display display, Config config,
+        VsyncPeriodNanos vsyncPeriodNanos,
+        VsyncPeriodChangeConstraints vsyncPeriodChangeConstraints)
+        generates (Error error, int64_t newVsyncAppliedTime);
 };
diff --git a/graphics/composer/2.4/types.hal b/graphics/composer/2.4/types.hal
new file mode 100644
index 0000000..b45d7a6
--- /dev/null
+++ b/graphics/composer/2.4/types.hal
@@ -0,0 +1,32 @@
+/*
+ * Copyright 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.
+ */
+
+package android.hardware.graphics.composer@2.4;
+
+import @2.1::Error;
+
+enum Error : @2.1::Error {
+    /**
+     * Invalid vsync period
+     */
+    BAD_VSYNC_PERIOD = 9,
+    /**
+     * Seamless requirements cannot be met
+     */
+    SEAMLESS_NOT_POSSIBLE = 10,
+};
+
+typedef uint32_t VsyncPeriodNanos;
diff --git a/graphics/composer/2.4/utils/command-buffer/include/composer-command-buffer/2.4/ComposerCommandBuffer.h b/graphics/composer/2.4/utils/command-buffer/include/composer-command-buffer/2.4/ComposerCommandBuffer.h
index 6b64c16..cb391be 100644
--- a/graphics/composer/2.4/utils/command-buffer/include/composer-command-buffer/2.4/ComposerCommandBuffer.h
+++ b/graphics/composer/2.4/utils/command-buffer/include/composer-command-buffer/2.4/ComposerCommandBuffer.h
@@ -34,7 +34,7 @@
 namespace V2_4 {
 
 using android::hardware::MessageQueue;
-using android::hardware::graphics::composer::V2_1::Error;
+using android::hardware::graphics::composer::V2_4::Error;
 using android::hardware::graphics::composer::V2_4::IComposerClient;
 
 // This class helps build a command queue.  Note that all sizes/lengths are in
diff --git a/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerClient.h b/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerClient.h
index c810186..ddf209b 100644
--- a/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerClient.h
+++ b/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerClient.h
@@ -20,8 +20,10 @@
 #warning "ComposerClient.h included without LOG_TAG"
 #endif
 
+#include <android/hardware/graphics/composer/2.4/IComposerCallback.h>
 #include <android/hardware/graphics/composer/2.4/IComposerClient.h>
 #include <composer-hal/2.4/ComposerHal.h>
+#include <composer-resources/2.1/ComposerResources.h>
 
 namespace android {
 namespace hardware {
@@ -38,6 +40,54 @@
   public:
     ComposerClientImpl(Hal* hal) : BaseType2_3(hal) {}
 
+    ~ComposerClientImpl() override { mHal->unregisterEventCallback_2_4(); }
+
+    class HalEventCallback : public Hal::EventCallback_2_4 {
+      public:
+        HalEventCallback(const sp<IComposerCallback> callback,
+                         V2_1::hal::ComposerResources* resources)
+            : mCallback(callback), mResources(resources) {}
+
+        void onHotplug(Display display, IComposerCallback::Connection connected) override {
+            if (connected == IComposerCallback::Connection::CONNECTED) {
+                mResources->addPhysicalDisplay(display);
+            } else if (connected == IComposerCallback::Connection::DISCONNECTED) {
+                mResources->removeDisplay(display);
+            }
+
+            auto ret = mCallback->onHotplug(display, connected);
+            ALOGE_IF(!ret.isOk(), "failed to send onHotplug: %s", ret.description().c_str());
+        }
+
+        void onRefresh(Display display) override {
+            mResources->setDisplayMustValidateState(display, true);
+            auto ret = mCallback->onRefresh(display);
+            ALOGE_IF(!ret.isOk(), "failed to send onRefresh: %s", ret.description().c_str());
+        }
+
+        void onVsync(Display display, int64_t timestamp) override {
+            auto ret = mCallback->onVsync(display, timestamp);
+            ALOGE_IF(!ret.isOk(), "failed to send onVsync: %s", ret.description().c_str());
+        }
+
+        void onVsync_2_4(Display display, int64_t timestamp,
+                         VsyncPeriodNanos vsyncPeriodNanos) override {
+            auto ret = mCallback->onVsync_2_4(display, timestamp, vsyncPeriodNanos);
+            ALOGE_IF(!ret.isOk(), "failed to send onVsync_2_4: %s", ret.description().c_str());
+        }
+
+      protected:
+        const sp<IComposerCallback> mCallback;
+        V2_1::hal::ComposerResources* const mResources;
+    };
+
+    Return<void> registerCallback_2_4(const sp<IComposerCallback>& callback) override {
+        // no locking as we require this function to be called only once
+        mHalEventCallback_2_4 = std::make_unique<HalEventCallback>(callback, mResources.get());
+        mHal->registerEventCallback_2_4(mHalEventCallback_2_4.get());
+        return Void();
+    }
+
     Return<void> getDisplayCapabilities_2_4(
             Display display, IComposerClient::getDisplayCapabilities_2_4_cb hidl_cb) override {
         std::vector<IComposerClient::DisplayCapability> capabilities;
@@ -54,6 +104,36 @@
         return Void();
     }
 
+    Return<void> getSupportedDisplayVsyncPeriods(
+            Display display, Config config,
+            IComposerClient::getSupportedDisplayVsyncPeriods_cb hidl_cb) override {
+        std::vector<VsyncPeriodNanos> supportedVsyncPeriods;
+        Error error =
+                mHal->getSupportedDisplayVsyncPeriods(display, config, &supportedVsyncPeriods);
+        hidl_cb(error, supportedVsyncPeriods);
+        return Void();
+    }
+
+    Return<void> getDisplayVsyncPeriod(Display display,
+                                       IComposerClient::getDisplayVsyncPeriod_cb hidl_cb) override {
+        VsyncPeriodNanos vsyncPeriods;
+        Error error = mHal->getDisplayVsyncPeriod(display, &vsyncPeriods);
+        hidl_cb(error, vsyncPeriods);
+        return Void();
+    }
+
+    Return<void> setActiveConfigAndVsyncPeriod(
+            Display display, Config config, VsyncPeriodNanos vsyncPeriodNanos,
+            const IComposerClient::VsyncPeriodChangeConstraints& vsyncPeriodChangeConstraints,
+            IComposerClient::setActiveConfigAndVsyncPeriod_cb hidl_cb) override {
+        int64_t newVsyncAppliedTime = 0;
+        Error error = mHal->setActiveConfigAndVsyncPeriod(display, config, vsyncPeriodNanos,
+                                                          vsyncPeriodChangeConstraints,
+                                                          &newVsyncAppliedTime);
+        hidl_cb(error, newVsyncAppliedTime);
+        return Void();
+    }
+
     static std::unique_ptr<ComposerClientImpl> create(Hal* hal) {
         auto client = std::make_unique<ComposerClientImpl>(hal);
         return client->init() ? std::move(client) : nullptr;
@@ -63,6 +143,8 @@
     using BaseType2_3 = V2_3::hal::detail::ComposerClientImpl<Interface, Hal>;
     using BaseType2_1 = V2_1::hal::detail::ComposerClientImpl<Interface, Hal>;
     using BaseType2_1::mHal;
+    std::unique_ptr<HalEventCallback> mHalEventCallback_2_4;
+    using BaseType2_1::mResources;
 };
 
 }  // namespace detail
diff --git a/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerHal.h b/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerHal.h
index c3bb535..0739f62 100644
--- a/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerHal.h
+++ b/graphics/composer/2.4/utils/hal/include/composer-hal/2.4/ComposerHal.h
@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <android/hardware/graphics/composer/2.4/types.h>
 #include <composer-hal/2.3/ComposerHal.h>
 
 namespace android {
@@ -30,16 +31,39 @@
 using common::V1_2::Dataspace;
 using common::V1_2::Hdr;
 using common::V1_2::PixelFormat;
+using V2_1::Config;
 using V2_1::Display;
-using V2_1::Error;
 using V2_1::Layer;
+using V2_4::Error;
+using V2_4::VsyncPeriodNanos;
 
 class ComposerHal : public V2_3::hal::ComposerHal {
   public:
+    class EventCallback_2_4 {
+      public:
+        virtual ~EventCallback_2_4() = default;
+        virtual void onHotplug(Display display, IComposerCallback::Connection connected) = 0;
+        virtual void onRefresh(Display display) = 0;
+        virtual void onVsync(Display display, int64_t timestamp) = 0;
+        virtual void onVsync_2_4(Display display, int64_t timestamp,
+                                 VsyncPeriodNanos vsyncPeriodNanos) = 0;
+    };
+
+    virtual void registerEventCallback_2_4(EventCallback_2_4* callback) = 0;
+
+    virtual void unregisterEventCallback_2_4() = 0;
+
     virtual Error getDisplayCapabilities_2_4(
             Display display, std::vector<IComposerClient::DisplayCapability>* outCapabilities) = 0;
     virtual Error getDisplayConnectionType(Display display,
                                            IComposerClient::DisplayConnectionType* outType) = 0;
+    virtual Error getSupportedDisplayVsyncPeriods(
+            Display display, Config config, std::vector<VsyncPeriodNanos>* outVsyncPeriod) = 0;
+    virtual Error getDisplayVsyncPeriod(Display display, VsyncPeriodNanos* outVsyncPeriod) = 0;
+    virtual Error setActiveConfigAndVsyncPeriod(
+            Display display, Config config, VsyncPeriodNanos vsyncPeriodNanos,
+            const IComposerClient::VsyncPeriodChangeConstraints& vsyncPeriodChangeConstraints,
+            int64_t* outNewVsyncAppliedTime) = 0;
 };
 
 }  // namespace hal
diff --git a/graphics/composer/2.4/utils/passthrough/include/composer-passthrough/2.4/HwcHal.h b/graphics/composer/2.4/utils/passthrough/include/composer-passthrough/2.4/HwcHal.h
index fd05f66..3420c8c 100644
--- a/graphics/composer/2.4/utils/passthrough/include/composer-passthrough/2.4/HwcHal.h
+++ b/graphics/composer/2.4/utils/passthrough/include/composer-passthrough/2.4/HwcHal.h
@@ -22,6 +22,7 @@
 
 #include <type_traits>
 
+#include <android/hardware/graphics/composer/2.4/IComposerClient.h>
 #include <composer-hal/2.4/ComposerHal.h>
 #include <composer-passthrough/2.3/HwcHal.h>
 
@@ -39,18 +40,49 @@
 using common::V1_2::Dataspace;
 using common::V1_2::Hdr;
 using common::V1_2::PixelFormat;
+using V2_1::Config;
 using V2_1::Display;
-using V2_1::Error;
+using V2_4::Error;
 
 // HwcHalImpl implements V2_*::hal::ComposerHal on top of hwcomposer2
 template <typename Hal>
 class HwcHalImpl : public V2_3::passthrough::detail::HwcHalImpl<Hal> {
   public:
+    void registerEventCallback_2_4(hal::ComposerHal::EventCallback_2_4* callback) override {
+        mEventCallback_2_4 = callback;
+
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_HOTPLUG, this,
+                                   reinterpret_cast<hwc2_function_pointer_t>(hotplugHook));
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_REFRESH, this,
+                                   reinterpret_cast<hwc2_function_pointer_t>(refreshHook));
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_VSYNC, this,
+                                   reinterpret_cast<hwc2_function_pointer_t>(vsyncHook));
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_VSYNC_2_4, this,
+                                   reinterpret_cast<hwc2_function_pointer_t>(vsync_2_4_Hook));
+    }
+
+    void unregisterEventCallback_2_4() override {
+        // we assume the callback functions
+        //
+        //  - can be unregistered
+        //  - can be in-flight
+        //  - will never be called afterward
+        //
+        // which is likely incorrect
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_HOTPLUG, this, nullptr);
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_REFRESH, this, nullptr);
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_VSYNC, this, nullptr);
+        mDispatch.registerCallback(mDevice, HWC2_CALLBACK_VSYNC_2_4, this, nullptr);
+
+        mEventCallback_2_4 = nullptr;
+    }
+
     Error getDisplayCapabilities_2_4(
             Display display,
             std::vector<IComposerClient::DisplayCapability>* outCapabilities) override {
         std::vector<V2_3::IComposerClient::DisplayCapability> capabilities;
-        Error error = BaseType2_3::getDisplayCapabilities(display, &capabilities);
+        V2_3::Error error_2_3 = BaseType2_3::getDisplayCapabilities(display, &capabilities);
+        Error error = static_cast<Error>(error_2_3);
         if (error != Error::NONE) {
             return error;
         }
@@ -74,6 +106,63 @@
         return static_cast<Error>(error);
     }
 
+    Error getSupportedDisplayVsyncPeriods(Display display, Config config,
+                                          std::vector<VsyncPeriodNanos>* outVsyncPeriods) override {
+        if (!mDispatch.getSupportedDisplayVsyncPeriods) {
+            return Error::UNSUPPORTED;
+        }
+
+        uint32_t count = 0;
+        int32_t error = mDispatch.getSupportedDisplayVsyncPeriods(mDevice, display, config, &count,
+                                                                  nullptr);
+        if (error != HWC2_ERROR_NONE) {
+            return static_cast<Error>(error);
+        }
+        outVsyncPeriods->resize(count);
+        error = mDispatch.getSupportedDisplayVsyncPeriods(mDevice, display, config, &count,
+                                                          outVsyncPeriods->data());
+        if (error != HWC2_ERROR_NONE) {
+            *outVsyncPeriods = std::vector<VsyncPeriodNanos>();
+            return static_cast<Error>(error);
+        }
+        return Error::NONE;
+    }
+
+    Error getDisplayVsyncPeriod(Display display, VsyncPeriodNanos* outVsyncPeriod) override {
+        if (!mDispatch.getDisplayVsyncPeriod) {
+            return Error::UNSUPPORTED;
+        }
+
+        int32_t error = mDispatch.getDisplayVsyncPeriod(mDevice, display, outVsyncPeriod);
+        if (error != HWC2_ERROR_NONE) {
+            return static_cast<Error>(error);
+        }
+        return Error::NONE;
+    }
+
+    Error setActiveConfigAndVsyncPeriod(
+            Display display, Config config, VsyncPeriodNanos vsyncPeriodNanos,
+            const IComposerClient::VsyncPeriodChangeConstraints& vsyncPeriodChangeConstraints,
+            int64_t* outNewVsyncAppliedTime) override {
+        if (!mDispatch.setActiveConfigAndVsyncPeriod) {
+            return Error::UNSUPPORTED;
+        }
+
+        hwc_vsync_period_change_constraints_t vsync_period_change_constraints;
+        vsync_period_change_constraints.desiredTimeNanos =
+                vsyncPeriodChangeConstraints.desiredTimeNanos;
+        vsync_period_change_constraints.seamlessRequired =
+                vsyncPeriodChangeConstraints.seamlessRequired;
+
+        int32_t error = mDispatch.setActiveConfigAndVsyncPeriod(
+                mDevice, display, config, vsyncPeriodNanos, &vsync_period_change_constraints,
+                outNewVsyncAppliedTime);
+        if (error != HWC2_ERROR_NONE) {
+            return static_cast<Error>(error);
+        }
+        return Error::NONE;
+    }
+
   protected:
     bool initDispatch() override {
         if (!BaseType2_3::initDispatch()) {
@@ -82,14 +171,51 @@
 
         this->initOptionalDispatch(HWC2_FUNCTION_GET_DISPLAY_CONNECTION_TYPE,
                                    &mDispatch.getDisplayConnectionType);
+        this->initOptionalDispatch(HWC2_FUNCTION_REGISTER_CALLBACK, &mDispatch.registerCallback);
+        this->initOptionalDispatch(HWC2_FUNCTION_GET_SUPPORTED_DISPLAY_VSYNC_PERIODS,
+                                   &mDispatch.getSupportedDisplayVsyncPeriods);
+        this->initOptionalDispatch(HWC2_FUNCTION_GET_DISPLAY_VSYNC_PERIOD,
+                                   &mDispatch.getDisplayVsyncPeriod);
+        this->initOptionalDispatch(HWC2_FUNCTION_SET_ACTIVE_CONFIG_AND_VSYNC_PERIOD,
+                                   &mDispatch.setActiveConfigAndVsyncPeriod);
         return true;
     }
 
+    static void hotplugHook(hwc2_callback_data_t callbackData, hwc2_display_t display,
+                            int32_t connected) {
+        auto hal = static_cast<HwcHalImpl*>(callbackData);
+        hal->mEventCallback_2_4->onHotplug(display,
+                                           static_cast<IComposerCallback::Connection>(connected));
+    }
+
+    static void refreshHook(hwc2_callback_data_t callbackData, hwc2_display_t display) {
+        auto hal = static_cast<HwcHalImpl*>(callbackData);
+        hal->mEventCallback_2_4->onRefresh(display);
+    }
+
+    static void vsyncHook(hwc2_callback_data_t callbackData, hwc2_display_t display,
+                          int64_t timestamp) {
+        auto hal = static_cast<HwcHalImpl*>(callbackData);
+        hal->mEventCallback_2_4->onVsync(display, timestamp);
+    }
+
+    static void vsync_2_4_Hook(hwc2_callback_data_t callbackData, hwc2_display_t display,
+                               int64_t timestamp, hwc2_vsync_period_t vsyncPeriodNanos) {
+        auto hal = static_cast<HwcHalImpl*>(callbackData);
+        hal->mEventCallback_2_4->onVsync_2_4(display, timestamp, vsyncPeriodNanos);
+    }
+
   private:
     struct {
         HWC2_PFN_GET_DISPLAY_CONNECTION_TYPE getDisplayConnectionType;
+        HWC2_PFN_REGISTER_CALLBACK registerCallback;
+        HWC2_PFN_GET_SUPPORTED_DISPLAY_VSYNC_PERIODS getSupportedDisplayVsyncPeriods;
+        HWC2_PFN_GET_DISPLAY_VSYNC_PERIOD getDisplayVsyncPeriod;
+        HWC2_PFN_SET_ACTIVE_CONFIG_AND_VSYNC_PERIOD setActiveConfigAndVsyncPeriod;
     } mDispatch = {};
 
+    hal::ComposerHal::EventCallback_2_4* mEventCallback_2_4 = nullptr;
+
     using BaseType2_1 = V2_1::passthrough::detail::HwcHalImpl<Hal>;
     using BaseType2_3 = V2_3::passthrough::detail::HwcHalImpl<Hal>;
     using BaseType2_1::mDevice;
diff --git a/graphics/composer/2.4/utils/vts/ComposerVts.cpp b/graphics/composer/2.4/utils/vts/ComposerVts.cpp
index 937b50e..b02a59a 100644
--- a/graphics/composer/2.4/utils/vts/ComposerVts.cpp
+++ b/graphics/composer/2.4/utils/vts/ComposerVts.cpp
@@ -25,7 +25,7 @@
 namespace V2_4 {
 namespace vts {
 
-using V2_1::Error;
+using V2_4::Error;
 
 Composer::Composer() : Composer(::testing::VtsHalHidlTargetTestBase::getService<IComposer>()) {}
 
@@ -70,6 +70,40 @@
     return error;
 }
 
+Error ComposerClient::getSupportedDisplayVsyncPeriods(
+        Display display, Config config, std::vector<VsyncPeriodNanos>* outSupportedVsyncPeriods) {
+    Error error = Error::NONE;
+    mClient->getSupportedDisplayVsyncPeriods(
+            display, config, [&](const auto& tmpError, const auto& tmpSupportedVsyncPeriods) {
+                error = tmpError;
+                *outSupportedVsyncPeriods = tmpSupportedVsyncPeriods;
+            });
+    return error;
+}
+
+Error ComposerClient::getDisplayVsyncPeriod(Display display, VsyncPeriodNanos* outVsyncPeriod) {
+    Error error = Error::NONE;
+    mClient->getDisplayVsyncPeriod(display, [&](const auto& tmpError, const auto& tmpVsyncPeriod) {
+        error = tmpError;
+        *outVsyncPeriod = tmpVsyncPeriod;
+    });
+    return error;
+}
+
+Error ComposerClient::setActiveConfigAndVsyncPeriod(
+        Display display, Config config, VsyncPeriodNanos vsyncPeriodNanos,
+        const IComposerClient::VsyncPeriodChangeConstraints& vsyncPeriodChangeConstraints,
+        int64_t* outNewVsyncAppliedTime) {
+    Error error = Error::NONE;
+    mClient->setActiveConfigAndVsyncPeriod(
+            display, config, vsyncPeriodNanos, vsyncPeriodChangeConstraints,
+            [&](const auto& tmpError, const auto& tmpNewVsyncAppliedTime) {
+                error = tmpError;
+                *outNewVsyncAppliedTime = tmpNewVsyncAppliedTime;
+            });
+    return error;
+}
+
 }  // namespace vts
 }  // namespace V2_4
 }  // namespace composer
diff --git a/graphics/composer/2.4/utils/vts/include/composer-vts/2.4/ComposerVts.h b/graphics/composer/2.4/utils/vts/include/composer-vts/2.4/ComposerVts.h
index a7d7f86..e8a3905 100644
--- a/graphics/composer/2.4/utils/vts/include/composer-vts/2.4/ComposerVts.h
+++ b/graphics/composer/2.4/utils/vts/include/composer-vts/2.4/ComposerVts.h
@@ -37,10 +37,12 @@
 using common::V1_2::Dataspace;
 using common::V1_2::Hdr;
 using common::V1_2::PixelFormat;
+using V2_1::Config;
 using V2_1::Display;
-using V2_1::Error;
+using V2_4::Error;
 using V2_4::IComposer;
 using V2_4::IComposerClient;
+using V2_4::VsyncPeriodNanos;
 
 class ComposerClient;
 
@@ -74,6 +76,16 @@
     Error getDisplayConnectionType(Display display,
                                    IComposerClient::DisplayConnectionType* outType);
 
+    Error getSupportedDisplayVsyncPeriods(Display display, Config config,
+                                          std::vector<VsyncPeriodNanos>* outSupportedVsyncPeriods);
+
+    Error getDisplayVsyncPeriod(Display display, VsyncPeriodNanos* outVsyncPeriods);
+
+    Error setActiveConfigAndVsyncPeriod(
+            Display display, Config config, VsyncPeriodNanos vsyncPeriodNanos,
+            const IComposerClient::VsyncPeriodChangeConstraints& vsyncPeriodChangeConstraints,
+            int64_t* outNewVsyncAppliedTime);
+
   private:
     const sp<IComposerClient> mClient;
 };
diff --git a/graphics/composer/2.4/vts/functional/VtsHalGraphicsComposerV2_4TargetTest.cpp b/graphics/composer/2.4/vts/functional/VtsHalGraphicsComposerV2_4TargetTest.cpp
index 76c0039..3d967fc 100644
--- a/graphics/composer/2.4/vts/functional/VtsHalGraphicsComposerV2_4TargetTest.cpp
+++ b/graphics/composer/2.4/vts/functional/VtsHalGraphicsComposerV2_4TargetTest.cpp
@@ -17,6 +17,7 @@
 #define LOG_TAG "graphics_composer_hidl_hal_test@2.4"
 
 #include <algorithm>
+#include <thread>
 
 #include <VtsHalHidlTargetTestBase.h>
 #include <android-base/logging.h>
@@ -26,6 +27,7 @@
 #include <composer-vts/2.1/TestCommandReader.h>
 #include <composer-vts/2.4/ComposerVts.h>
 #include <mapper-vts/2.0/MapperVts.h>
+#include <utils/Timers.h>
 
 namespace android {
 namespace hardware {
@@ -110,8 +112,27 @@
         return 0;
     }
 
+    // returns an invalid config id (one that has not been registered to a
+    // display).  Currently assuming that a device will never have close to
+    // std::numeric_limit<uint64_t>::max() configs registered while running tests
+    Display GetInvalidConfigId(Display display) {
+        std::vector<Config> validConfigs = mComposerClient->getDisplayConfigs(display);
+        uint64_t id = std::numeric_limits<uint64_t>::max();
+        while (id > 0) {
+            if (std::find(validConfigs.begin(), validConfigs.end(), id) == validConfigs.end()) {
+                return id;
+            }
+            id--;
+        }
+
+        return 0;
+    }
+
     void execute() { mComposerClient->execute(mReader.get(), mWriter.get()); }
 
+    void Test_setActiveConfigAndVsyncPeriod(
+            const IComposerClient::VsyncPeriodChangeConstraints& constraints);
+
     std::unique_ptr<Composer> mComposer;
     std::unique_ptr<ComposerClient> mComposerClient;
     sp<V2_1::vts::GraphicsComposerCallback> mComposerCallback;
@@ -189,6 +210,162 @@
     }
 }
 
+TEST_F(GraphicsComposerHidlTest, getSupportedDisplayVsyncPeriods_BadDisplay) {
+    std::vector<VsyncPeriodNanos> supportedVsyncPeriods;
+    EXPECT_EQ(Error::BAD_DISPLAY, mComposerClient->getSupportedDisplayVsyncPeriods(
+                                          mInvalidDisplayId, Config(0), &supportedVsyncPeriods));
+}
+
+TEST_F(GraphicsComposerHidlTest, getSupportedDisplayVsyncPeriods_BadConfig) {
+    for (Display display : mComposerCallback->getDisplays()) {
+        Config invalidConfigId = GetInvalidConfigId(display);
+        std::vector<VsyncPeriodNanos> supportedVsyncPeriods;
+        EXPECT_EQ(Error::BAD_CONFIG, mComposerClient->getSupportedDisplayVsyncPeriods(
+                                             display, invalidConfigId, &supportedVsyncPeriods));
+    }
+}
+
+TEST_F(GraphicsComposerHidlTest, getSupportedDisplayVsyncPeriods) {
+    for (Display display : mComposerCallback->getDisplays()) {
+        for (Config config : mComposerClient->getDisplayConfigs(display)) {
+            std::vector<VsyncPeriodNanos> supportedVsyncPeriods;
+
+            // Get the default vsync period from the config
+            VsyncPeriodNanos defaultVsyncPeiord = mComposerClient->getDisplayAttribute(
+                    display, config, IComposerClient::Attribute::VSYNC_PERIOD);
+            // Get all supported vsync periods for this config
+            EXPECT_EQ(Error::NONE, mComposerClient->getSupportedDisplayVsyncPeriods(
+                                           display, config, &supportedVsyncPeriods));
+            // Default vsync period must be present in the list
+            EXPECT_NE(std::find(supportedVsyncPeriods.begin(), supportedVsyncPeriods.end(),
+                                defaultVsyncPeiord),
+                      supportedVsyncPeriods.end());
+
+            // Each vsync period must be unique
+            std::unordered_set<VsyncPeriodNanos> vsyncPeriodSet;
+            for (VsyncPeriodNanos vsyncPeriodNanos : supportedVsyncPeriods) {
+                EXPECT_TRUE(vsyncPeriodSet.insert(vsyncPeriodNanos).second);
+            }
+        }
+    }
+}
+
+TEST_F(GraphicsComposerHidlTest, getDisplayVsyncPeriod_BadDisplay) {
+    VsyncPeriodNanos vsyncPeriodNanos;
+    EXPECT_EQ(Error::BAD_DISPLAY,
+              mComposerClient->getDisplayVsyncPeriod(mInvalidDisplayId, &vsyncPeriodNanos));
+}
+
+TEST_F(GraphicsComposerHidlTest, setActiveConfigAndVsyncPeriod_BadDisplay) {
+    int64_t newVsyncAppliedTime;
+    IComposerClient::VsyncPeriodChangeConstraints constraints;
+
+    constraints.seamlessRequired = false;
+    constraints.desiredTimeNanos = systemTime();
+
+    EXPECT_EQ(Error::BAD_DISPLAY, mComposerClient->setActiveConfigAndVsyncPeriod(
+                                          mInvalidDisplayId, Config(0), VsyncPeriodNanos(0),
+                                          constraints, &newVsyncAppliedTime));
+}
+
+TEST_F(GraphicsComposerHidlTest, setActiveConfigAndVsyncPeriod_BadConfig) {
+    int64_t newVsyncAppliedTime;
+    IComposerClient::VsyncPeriodChangeConstraints constraints;
+
+    constraints.seamlessRequired = false;
+    constraints.desiredTimeNanos = systemTime();
+
+    for (Display display : mComposerCallback->getDisplays()) {
+        Config invalidConfigId = GetInvalidConfigId(display);
+        EXPECT_EQ(Error::BAD_CONFIG, mComposerClient->setActiveConfigAndVsyncPeriod(
+                                             display, invalidConfigId, VsyncPeriodNanos(0),
+                                             constraints, &newVsyncAppliedTime));
+    }
+}
+
+TEST_F(GraphicsComposerHidlTest, setActiveConfigAndVsyncPeriod_BadVsyncPeriod) {
+    int64_t newVsyncAppliedTime;
+    IComposerClient::VsyncPeriodChangeConstraints constraints;
+
+    constraints.seamlessRequired = false;
+    constraints.desiredTimeNanos = systemTime();
+
+    for (Display display : mComposerCallback->getDisplays()) {
+        for (Config config : mComposerClient->getDisplayConfigs(display)) {
+            EXPECT_EQ(Error::BAD_VSYNC_PERIOD, mComposerClient->setActiveConfigAndVsyncPeriod(
+                                                       display, config, VsyncPeriodNanos(0),
+                                                       constraints, &newVsyncAppliedTime));
+        }
+    }
+}
+
+void GraphicsComposerHidlTest::Test_setActiveConfigAndVsyncPeriod(
+        const IComposerClient::VsyncPeriodChangeConstraints& constraints) {
+    int64_t newVsyncAppliedTime;
+
+    for (Display display : mComposerCallback->getDisplays()) {
+        for (Config config : mComposerClient->getDisplayConfigs(display)) {
+            std::vector<VsyncPeriodNanos> supportedVsyncPeriods;
+
+            EXPECT_EQ(Error::NONE, mComposerClient->getSupportedDisplayVsyncPeriods(
+                                           display, config, &supportedVsyncPeriods));
+            for (VsyncPeriodNanos newVsyncPeriod : supportedVsyncPeriods) {
+                VsyncPeriodNanos vsyncPeriodNanos;
+                EXPECT_EQ(Error::NONE,
+                          mComposerClient->getDisplayVsyncPeriod(display, &vsyncPeriodNanos));
+
+                if (vsyncPeriodNanos == newVsyncPeriod) {
+                    continue;
+                }
+
+                EXPECT_EQ(Error::NONE, mComposerClient->setActiveConfigAndVsyncPeriod(
+                                               display, config, newVsyncPeriod, constraints,
+                                               &newVsyncAppliedTime));
+
+                EXPECT_TRUE(newVsyncAppliedTime >= constraints.desiredTimeNanos);
+
+                // Refresh rate should change within a reasonable time
+                constexpr nsecs_t kReasonableTimeForChange = 1'000'000'000;  // 1 second
+                EXPECT_TRUE(newVsyncAppliedTime - constraints.desiredTimeNanos <=
+                            kReasonableTimeForChange);
+
+                while (systemTime() <= newVsyncAppliedTime) {
+                    EXPECT_EQ(Error::NONE,
+                              mComposerClient->getDisplayVsyncPeriod(display, &vsyncPeriodNanos));
+                    if (systemTime() <= constraints.desiredTimeNanos) {
+                        EXPECT_NE(vsyncPeriodNanos, newVsyncPeriod);
+                    }
+
+                    if (vsyncPeriodNanos == newVsyncPeriod) {
+                        break;
+                    }
+                    std::this_thread::sleep_for(10ms);
+                }
+                EXPECT_EQ(Error::NONE,
+                          mComposerClient->getDisplayVsyncPeriod(display, &vsyncPeriodNanos));
+                EXPECT_EQ(vsyncPeriodNanos, newVsyncPeriod);
+            }
+        }
+    }
+}
+
+TEST_F(GraphicsComposerHidlTest, setActiveConfigAndVsyncPeriod) {
+    IComposerClient::VsyncPeriodChangeConstraints constraints;
+
+    constraints.seamlessRequired = false;
+    constraints.desiredTimeNanos = systemTime();
+    Test_setActiveConfigAndVsyncPeriod(constraints);
+}
+
+TEST_F(GraphicsComposerHidlTest, setActiveConfigAndVsyncPeriod_delayed) {
+    IComposerClient::VsyncPeriodChangeConstraints constraints;
+
+    constexpr auto kDelayForChange = 300ms;
+    constraints.seamlessRequired = false;
+    constraints.desiredTimeNanos = systemTime() + kDelayForChange.count();
+    Test_setActiveConfigAndVsyncPeriod(constraints);
+}
+
 }  // namespace
 }  // namespace vts
 }  // namespace V2_4
diff --git a/health/1.0/vts/functional/Android.bp b/health/1.0/vts/functional/Android.bp
index c14dcee..be2d206 100644
--- a/health/1.0/vts/functional/Android.bp
+++ b/health/1.0/vts/functional/Android.bp
@@ -19,5 +19,5 @@
     defaults: ["VtsHalTargetTestDefaults"],
     srcs: ["VtsHalHealthV1_0TargetTest.cpp"],
     static_libs: ["android.hardware.health@1.0"],
-    test_suites: ["general-tests"],
+    test_suites: ["general-tests", "vts-core"],
 }
diff --git a/health/1.0/vts/functional/VtsHalHealthV1_0TargetTest.cpp b/health/1.0/vts/functional/VtsHalHealthV1_0TargetTest.cpp
index 335d15d..b985a9f 100644
--- a/health/1.0/vts/functional/VtsHalHealthV1_0TargetTest.cpp
+++ b/health/1.0/vts/functional/VtsHalHealthV1_0TargetTest.cpp
@@ -18,11 +18,11 @@
 
 #include <android/hardware/health/1.0/IHealth.h>
 #include <android/hardware/health/1.0/types.h>
+#include <gtest/gtest.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
 #include <log/log.h>
 
-#include <VtsHalHidlTargetTestBase.h>
-#include <VtsHalHidlTargetTestEnvBase.h>
-
 using HealthConfig = ::android::hardware::health::V1_0::HealthConfig;
 using HealthInfo = ::android::hardware::health::V1_0::HealthInfo;
 using IHealth = ::android::hardware::health::V1_0::IHealth;
@@ -30,25 +30,10 @@
 
 using ::android::sp;
 
-// Test environment for Health HIDL HAL.
-class HealthHidlEnvironment : public ::testing::VtsHalHidlTargetTestEnvBase {
-   public:
-    // get the test environment singleton
-    static HealthHidlEnvironment* Instance() {
-        static HealthHidlEnvironment* instance = new HealthHidlEnvironment;
-        return instance;
-    }
-
-    virtual void registerTestServices() override { registerTestService<IHealth>(); }
-   private:
-    HealthHidlEnvironment() {}
-};
-
-class HealthHidlTest : public ::testing::VtsHalHidlTargetTestBase {
+class HealthHidlTest : public ::testing::TestWithParam<std::string> {
    public:
     virtual void SetUp() override {
-        health = ::testing::VtsHalHidlTargetTestBase::getService<IHealth>(
-            HealthHidlEnvironment::Instance()->getServiceName<IHealth>());
+        health = IHealth::getService(GetParam());
         ASSERT_NE(health, nullptr);
         health->init(config,
                      [&](const auto& halConfigOut) { config = halConfigOut; });
@@ -61,7 +46,7 @@
 /**
  * Ensure EnergyCounter call returns positive energy counter or NOT_SUPPORTED
  */
-TEST_F(HealthHidlTest, TestEnergyCounter) {
+TEST_P(HealthHidlTest, TestEnergyCounter) {
     Result result;
     int64_t energy = 0;
     health->energyCounter([&](Result ret, int64_t energyOut) {
@@ -73,11 +58,7 @@
     ASSERT_TRUE(result != Result::SUCCESS || energy > 0);
 }
 
-int main(int argc, char **argv) {
-    ::testing::AddGlobalTestEnvironment(HealthHidlEnvironment::Instance());
-    ::testing::InitGoogleTest(&argc, argv);
-    HealthHidlEnvironment::Instance()->init(&argc, argv);
-    int status = RUN_ALL_TESTS();
-    ALOGI("Test result = %d", status);
-    return status;
-}
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, HealthHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IHealth::descriptor)),
+        android::hardware::PrintInstanceNameToString);
diff --git a/health/2.0/README.md b/health/2.0/README.md
index 4ecfb9a..8a7c922 100644
--- a/health/2.0/README.md
+++ b/health/2.0/README.md
@@ -1,3 +1,8 @@
+# Implement the 2.1 HAL instead!
+
+It is strongly recommended that you implement the 2.1 HAL directly. See
+`hardware/interfaces/health/2.1/README.md` for more details.
+
 # Upgrading from Health 1.0 HAL
 
 1. Remove `android.hardware.health@1.0*` from `PRODUCT_PACKAGES`
diff --git a/health/2.1/README.md b/health/2.1/README.md
new file mode 100644
index 0000000..5a19d7b
--- /dev/null
+++ b/health/2.1/README.md
@@ -0,0 +1,245 @@
+# Implementing Health 2.1 HAL
+
+1. Install common binderized service. The binderized service `dlopen()`s
+   passthrough implementations on the device, so there is no need to write
+   your own.
+
+    ```mk
+    # Install default binderized implementation to vendor.
+    PRODUCT_PACKAGES += android.hardware.health@2.1-service
+    ```
+
+1. Delete existing VINTF manifest entry. Search for `android.hardware.health` in
+   your device manifest, and delete the whole `<hal>` entry for older versions
+   of the HAL. Instead, when `android.hardware.health@2.1-service` is installed,
+   a VINTF manifest fragment is installed to `/vendor/etc/vintf`, so there is
+   no need to manually specify it in your device manifest. See
+   [Manifest fragments](https://source.android.com/devices/architecture/vintf/objects#manifest-fragments)
+   for details.
+
+1. Install the proper passthrough implemetation.
+
+    1. If you want to use default implementation:
+
+        ```mk
+        # Install default passthrough implementation to vendor.
+        PRODUCT_PACKAGES += android.hardware.health@2.1-impl
+        ```
+
+        You are done. Otherwise, go to the next step.
+
+    1. If you want to write your own implementation,
+
+        1. Copy skeleton implementation from the [appendix](#impl).
+
+        1. Modify the implementation to suit your needs.
+
+            * If you have a board or device specific `libhealthd`, see
+              [Upgrading with  a customized libhealthd](#update-from-1-0).
+            * If you are upgrading from 1.0 health HAL, see
+              [Upgrading from Health HAL 1.0](#update-from-1-0).
+            * If you are upgrading from a customized 2.0 health HAL
+              implementation, See
+              [Upgrading from Health HAL 2.0](#update-from-2-0).
+
+        1. [Update necessary SELinux permissions](#selinux).
+
+        1. [Fix `/charger` symlink](#charger-symlink).
+
+# Upgrading with a customized libhealthd or from Health HAL 1.0 {#update-from-1-0}
+
+`libhealthd` contains two functions: `healthd_board_init()` and
+`healthd_board_battery_update()`. Similarly, Health HAL 1.0 contains `init()`
+and `update()`, with an additional `energyCounter()` function.
+
+* `healthd_board_init()` / `@1.0::IHealth.init()` should be called before
+  passing the `healthd_config` struct to your `HealthImpl` class. See
+  `HIDL_FETCH_IHealth` in [`HealthImpl.cpp`](#health_impl_cpp).
+
+* `healthd_board_battery_update()` / `@1.0::IHealth.update()` should be called
+  in `HealthImpl::UpdateHealthInfo()`. Example:
+
+  ```c++
+  void HealthImpl::UpdateHealthInfo(HealthInfo* health_info) {
+      struct BatteryProperties props;
+      convertFromHealthInfo(health_info->legacy.legacy, &props);
+      healthd_board_battery_update(&props);
+      convertToHealthInfo(&props, health_info->legacy.legacy);
+  }
+  ```
+  For efficiency, you should move code in `healthd_board_battery_update` to
+  `HealthImpl::UpdateHealthInfo` and modify `health_info` directly to avoid
+  conversion to `BatteryProperties`.
+
+* Code for `@1.0::IHealth.energyCounter()` should be moved to
+  `HealthImpl::getEnergyCounter()`. Example:
+
+  ```c++
+  Return<void> Health::getEnergyCounter(getEnergyCounter_cb _hidl_cb) {
+      int64_t energy = /* ... */;
+      _hidl_cb(Result::SUCCESS, energy);
+      return Void();
+  }
+  ```
+
+# Upgrading from Health HAL 2.0 {#update-from-2-0}
+
+* If you have implemented `healthd_board_init()` and/or
+  `healthd_board_battery_update()` (instead of using `libhealthd.default`),
+  see [the section above](#update-from-1-0)
+  for instructions to convert them.
+
+* If you have implemented `get_storage_info()` and/or `get_disk_stats()`
+  (instead of using libhealthstoragedefault), implement `HealthImpl::getDiskStats`
+  and/or `HealthImpl::getStorageInfo` directly. There is no need to override
+  `HealthImpl::getHealthInfo` or `HealthImpl::getHealthInfo_2_1` because they call
+  `getDiskStats` and `getStorageInfo` to retrieve storage information.
+
+# Update necessary SELinux permissions {#selinux}
+
+For example (replace `<device>` with the device name):
+```
+# device/<manufacturer>/<device>/sepolicy/vendor/hal_health_default.te
+# Add device specific permissions to hal_health_default domain, especially
+# if a device-specific libhealthd is used and/or device-specific storage related
+# APIs are implemented.
+```
+
+# Fix `/charger` symlink {#charger-symlink}
+If you are using `/charger` in your `init.rc` scripts, it is recommended
+(required for devices running in Android R) that the path is changed to
+`/system/bin/charger` instead.
+
+Search for `service charger` in your device configuration directory to see if
+this change applies to your device. Below is an example of how the script should
+look like:
+
+```
+service charger /system/bin/charger
+    class charger
+    user system
+    group system wakelock input
+    capabilities SYS_BOOT
+    file /dev/kmsg w
+    file /sys/fs/pstore/console-ramoops-0 r
+    file /sys/fs/pstore/console-ramoops r
+    file /proc/last_kmsg r
+```
+
+# Appendix: sample code for the implementation {#impl}
+
+## `device/<manufacturer>/<device>/health/Android.bp` {#android_bp}
+
+```bp
+cc_library_shared {
+    name: "android.hardware.health@2.1-impl-<device>",
+    stem: "android.hardware.health@2.0-impl-2.1-<device>",
+
+    // Install to vendor and recovery.
+    proprietary: true,
+    recovery_available: true,
+
+    relative_install_path: "hw",
+
+    shared_libs: [
+        "libbase",
+        "libcutils",
+        "libhidlbase",
+        "liblog",
+        "libutils",
+        "android.hardware.health@2.1",
+        "android.hardware.health@2.0",
+    ],
+
+    static_libs: [
+        "android.hardware.health@1.0-convert",
+        "libbatterymonitor",
+        "libhealthloop",
+        "libhealth2impl",
+        // "libhealthd.<device>"
+    ],
+
+    srcs: [
+        "HealthImpl.cpp",
+    ],
+
+    // No vintf_fragments because both -impl and -service should have been
+    // installed.
+}
+```
+
+## `device/<manufacturer>/<device>/health/HealthImpl.cpp` {#health_impl_cpp}
+
+```c++
+#include <memory>
+#include <string_view>
+
+#include <health/utils.h>
+#include <health2impl/Health.h>
+#include <hidl/Status.h>
+
+using ::android::sp;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::health::InitHealthdConfig;
+using ::android::hardware::health::V2_1::IHealth;
+using ::android::hidl::base::V1_0::IBase;
+
+using namespace std::literals;
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+// android::hardware::health::V2_1::implementation::Health implements most
+// defaults. Uncomment functions that you need to override.
+class HealthImpl : public Health {
+  public:
+    HealthImpl(std::unique_ptr<healthd_config>&& config)
+        : Health(std::move(config)) {}
+
+    // A subclass can override this if these information should be retrieved
+    // differently.
+    // Return<void> getChargeCounter(getChargeCounter_cb _hidl_cb) override;
+    // Return<void> getCurrentNow(getCurrentNow_cb _hidl_cb) override;
+    // Return<void> getCurrentAverage(getCurrentAverage_cb _hidl_cb) override;
+    // Return<void> getCapacity(getCapacity_cb _hidl_cb) override;
+    // Return<void> getEnergyCounter(getEnergyCounter_cb _hidl_cb) override;
+    // Return<void> getChargeStatus(getChargeStatus_cb _hidl_cb) override;
+    // Return<void> getStorageInfo(getStorageInfo_cb _hidl_cb) override;
+    // Return<void> getDiskStats(getDiskStats_cb _hidl_cb) override;
+    // Return<void> getHealthInfo(getHealthInfo_cb _hidl_cb) override;
+
+    // Functions introduced in Health HAL 2.1.
+    // Return<void> getHealthConfig(getHealthConfig_cb _hidl_cb) override;
+    // Return<void> getHealthInfo_2_1(getHealthInfo_2_1_cb _hidl_cb) override;
+    // Return<void> shouldKeepScreenOn(shouldKeepScreenOn_cb _hidl_cb) override;
+
+  protected:
+    // A subclass can override this to modify any health info object before
+    // returning to clients. This is similar to healthd_board_battery_update().
+    // By default, it does nothing.
+    // void UpdateHealthInfo(HealthInfo* health_info) override;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
+
+extern "C" IHealth* HIDL_FETCH_IHealth(const char* instance) {
+    using ::android::hardware::health::V2_1::implementation::HealthImpl;
+    if (instance != "default"sv) {
+        return nullptr;
+    }
+    auto config = std::make_unique<healthd_config>();
+    InitHealthdConfig(config.get());
+
+    // healthd_board_init(config.get());
+
+    return new HealthImpl(std::move(config));
+}
+```
diff --git a/health/2.1/default/Android.bp b/health/2.1/default/Android.bp
new file mode 100644
index 0000000..3649853
--- /dev/null
+++ b/health/2.1/default/Android.bp
@@ -0,0 +1,81 @@
+// 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.
+
+cc_defaults {
+    name: "android.hardware.health@2.1-impl-defaults",
+    relative_install_path: "hw",
+
+    shared_libs: [
+        "libbase",
+        "libcutils",
+        "libhidlbase",
+        "liblog",
+        "libutils",
+        "android.hardware.health@2.1",
+        "android.hardware.health@2.0",
+    ],
+
+    static_libs: [
+        "android.hardware.health@1.0-convert",
+        "libbatterymonitor",
+        "libhealthloop",
+        "libhealth2impl",
+    ],
+}
+
+// Default passthrough implementation of the health@2.1 HAL.
+// Passhtrough implementations of the health@2.1 HAL must be installed in
+// vendor in order to support charger.
+// Passhtrough implementations of the health@2.1 HAL must be installed in
+// recovery in order to allow recovery to check battery status.
+// See README.md for details.
+cc_library_shared {
+    name: "android.hardware.health@2.1-impl",
+    stem: "android.hardware.health@2.0-impl-2.1",
+
+    // Only vendor and recovery variants are allowed, not core.
+    vendor: true,
+    recovery_available: true,
+
+    defaults: ["android.hardware.health@2.1-impl-defaults"],
+
+    srcs: [
+        "impl.cpp",
+    ],
+
+    // No vintf_fragments because both -impl and -service should have been
+    // installed.
+}
+
+// Default binderized service of the health@2.1 HAL.
+// This binderized implementation dlopen()s the passthrough implementation,
+// so there is no need to implement your own.
+cc_binary {
+    name: "android.hardware.health@2.1-service",
+    vendor: true,
+    defaults: ["android.hardware.health@2.1-impl-defaults"],
+    init_rc: ["android.hardware.health@2.1-service.rc"],
+
+    srcs: [
+        "service.cpp",
+    ],
+
+    vintf_fragments: [
+        "android.hardware.health@2.1.xml"
+    ],
+
+    overrides: [
+        "healthd",
+    ],
+}
diff --git a/health/2.1/default/android.hardware.health@2.1-service.rc b/health/2.1/default/android.hardware.health@2.1-service.rc
new file mode 100644
index 0000000..917f1c2
--- /dev/null
+++ b/health/2.1/default/android.hardware.health@2.1-service.rc
@@ -0,0 +1,6 @@
+service health-hal-2-1 /vendor/bin/hw/android.hardware.health@2.1-service
+    class hal
+    user system
+    group system
+    capabilities WAKE_ALARM
+    file /dev/kmsg w
diff --git a/health/2.1/default/android.hardware.health@2.1.xml b/health/2.1/default/android.hardware.health@2.1.xml
new file mode 100644
index 0000000..34fdca6
--- /dev/null
+++ b/health/2.1/default/android.hardware.health@2.1.xml
@@ -0,0 +1,7 @@
+<manifest version="1.0" type="device">
+    <hal format="hidl">
+        <name>android.hardware.health</name>
+        <transport>hwbinder</transport>
+        <fqname>@2.1::IHealth/default</fqname>
+    </hal>
+</manifest>
diff --git a/health/2.1/default/impl.cpp b/health/2.1/default/impl.cpp
new file mode 100644
index 0000000..7389a21
--- /dev/null
+++ b/health/2.1/default/impl.cpp
@@ -0,0 +1,53 @@
+/*
+ * 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.
+ */
+
+#include <memory>
+#include <string_view>
+
+#include <health/utils.h>
+#include <health2impl/Health.h>
+
+using ::android::sp;
+using ::android::hardware::health::InitHealthdConfig;
+using ::android::hardware::health::V2_1::IHealth;
+using ::android::hardware::health::V2_1::implementation::Health;
+
+using namespace std::literals;
+
+// Passthrough implementation of the health service. Use default configuration.
+// It does not invoke callbacks unless update() is called explicitly. No
+// background thread is spawned to handle callbacks.
+//
+// The passthrough implementation is only allowed in recovery mode, charger, and
+// opened by the hwbinder service.
+// If Android is booted normally, the hwbinder service is used instead.
+//
+// This implementation only implements the "default" instance. It rejects
+// other instance names.
+// Note that the Android framework only reads values from the "default"
+// health HAL 2.1 instance.
+extern "C" IHealth* HIDL_FETCH_IHealth(const char* instance) {
+    if (instance != "default"sv) {
+        return nullptr;
+    }
+    auto config = std::make_unique<healthd_config>();
+    InitHealthdConfig(config.get());
+
+    // This implementation uses default config. If you want to customize it
+    // (e.g. with healthd_board_init), do it here.
+
+    return new Health(std::move(config));
+}
diff --git a/health/2.1/default/service.cpp b/health/2.1/default/service.cpp
new file mode 100644
index 0000000..f8334c5
--- /dev/null
+++ b/health/2.1/default/service.cpp
@@ -0,0 +1,37 @@
+/*
+ * 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 "android.hardware.health@2.1-service"
+
+#include <android-base/logging.h>
+#include <android/hardware/health/2.1/IHealth.h>
+#include <health2impl/BinderHealth.h>
+
+using ::android::sp;
+using ::android::hardware::health::V2_1::IHealth;
+using ::android::hardware::health::V2_1::implementation::BinderHealth;
+using IHealth_2_0 = ::android::hardware::health::V2_0::IHealth;
+
+static constexpr const char* gInstanceName = "default";
+
+int main(int /* argc */, char* /* argv */[]) {
+    sp<IHealth> passthrough =
+            IHealth::castFrom(IHealth_2_0::getService(gInstanceName, true /* getStub */));
+    CHECK(passthrough != nullptr)
+            << "Cannot find passthrough implementation of health 2.1 HAL for instance "
+            << gInstanceName;
+    sp<BinderHealth> binder = new BinderHealth(gInstanceName, passthrough);
+    return binder->StartLoop();
+}
diff --git a/health/utils/libhealth2impl/Android.bp b/health/utils/libhealth2impl/Android.bp
new file mode 100644
index 0000000..14374a2
--- /dev/null
+++ b/health/utils/libhealth2impl/Android.bp
@@ -0,0 +1,51 @@
+// 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.
+
+// A helper library for health@2.x HAL implementation.
+// HAL implementations can link to this library and extend the Health class.
+cc_library_static {
+    name: "libhealth2impl",
+    vendor_available: true,
+    recovery_available: true,
+    srcs: [
+        "BinderHealth.cpp",
+        "HalHealthLoop.cpp",
+        "Health.cpp",
+    ],
+    shared_libs: [
+        "libbase",
+        "libcutils",
+        "libhidlbase",
+        "liblog",
+        "libutils",
+        "android.hardware.health@2.1",
+        "android.hardware.health@2.0",
+    ],
+    static_libs: [
+        "libbatterymonitor",
+        "libhealthloop",
+        "android.hardware.health@1.0-convert",
+    ],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    export_static_lib_headers: [
+        "libbatterymonitor",
+        "libhealthloop",
+    ],
+    export_include_dirs: [
+        "include",
+    ],
+}
diff --git a/health/utils/libhealth2impl/BinderHealth.cpp b/health/utils/libhealth2impl/BinderHealth.cpp
new file mode 100644
index 0000000..625d0e0
--- /dev/null
+++ b/health/utils/libhealth2impl/BinderHealth.cpp
@@ -0,0 +1,190 @@
+/*
+ * 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.
+ */
+
+#include <health2impl/BinderHealth.h>
+
+#include <android-base/logging.h>
+#include <hidl/HidlTransportSupport.h>
+#include <hwbinder/IPCThreadState.h>
+
+#include <health2impl/Callback.h>
+#include <health2impl/Health.h>
+
+using android::hardware::handleTransportPoll;
+using android::hardware::IPCThreadState;
+using android::hardware::setupTransportPolling;
+
+using android::hardware::health::V2_0::Result;
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+bool IsDeadObjectLogged(const Return<void>& ret) {
+    if (ret.isOk()) return false;
+    if (ret.isDeadObject()) return true;
+    LOG(ERROR) << "Cannot call healthInfoChanged* on callback: " << ret.description();
+    return false;
+}
+
+BinderHealth::BinderHealth(const std::string& name, const sp<IHealth>& impl)
+    : HalHealthLoop(name, impl) {
+    CHECK_NE(this, impl.get());
+    CHECK(!impl->isRemote());
+}
+
+//
+// Methods that handle callbacks.
+//
+
+Return<Result> BinderHealth::registerCallback(const sp<V2_0::IHealthInfoCallback>& callback) {
+    if (callback == nullptr) {
+        return Result::SUCCESS;
+    }
+
+    Callback* wrapped = nullptr;
+    {
+        std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
+        wrapped = callbacks_.emplace_back(Wrap(callback)).get();
+        // unlock
+    }
+
+    auto linkRet = callback->linkToDeath(this, 0u /* cookie */);
+    if (!linkRet.withDefault(false)) {
+        LOG(WARNING) << __func__ << "Cannot link to death: "
+                     << (linkRet.isOk() ? "linkToDeath returns false" : linkRet.description());
+        // ignore the error
+    }
+
+    getHealthInfo_2_1([&](auto res, const auto& health_info) {
+        if (res != Result::SUCCESS) {
+            LOG(ERROR) << "Cannot call getHealthInfo_2_1: " << toString(res);
+            return;
+        }
+        auto ret = wrapped->Notify(health_info);
+        if (IsDeadObjectLogged(ret)) {
+            // Remove callback reference.
+            std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
+            auto it = std::find_if(callbacks_.begin(), callbacks_.end(),
+                                   [wrapped](const auto& cb) { return cb.get() == wrapped; });
+            if (it != callbacks_.end()) {
+                callbacks_.erase(it);
+            }
+            // unlock
+        }
+    });
+
+    return Result::SUCCESS;
+}
+
+bool BinderHealth::unregisterCallbackInternal(const sp<IBase>& callback) {
+    if (callback == nullptr) {
+        return false;
+    }
+
+    bool removed = false;
+    std::lock_guard<decltype(callbacks_lock_)> lock(callbacks_lock_);
+    for (auto it = callbacks_.begin(); it != callbacks_.end();) {
+        if (interfacesEqual((*it)->Get(), callback)) {
+            it = callbacks_.erase(it);
+            removed = true;
+        } else {
+            ++it;
+        }
+    }
+    (void)callback->unlinkToDeath(this).isOk();  // ignore errors
+    return removed;
+}
+
+Return<Result> BinderHealth::update() {
+    Result result = service()->update();
+    if (result != Result::SUCCESS) return result;
+    getHealthInfo_2_1([&](auto res, const auto& health_info) {
+        if (res != Result::SUCCESS) {
+            result = res;
+            return;
+        }
+        OnHealthInfoChanged(health_info);
+    });
+    return result;
+}
+
+Return<Result> BinderHealth::unregisterCallback(const sp<V2_0::IHealthInfoCallback>& callback) {
+    return unregisterCallbackInternal(callback) ? Result::SUCCESS : Result::NOT_FOUND;
+}
+
+void BinderHealth::OnHealthInfoChanged(const HealthInfo& health_info) {
+    // Notify all callbacks
+    std::unique_lock<decltype(callbacks_lock_)> lock(callbacks_lock_);
+    for (auto it = callbacks_.begin(); it != callbacks_.end();) {
+        auto ret = (*it)->Notify(health_info);
+        if (IsDeadObjectLogged(ret)) {
+            it = callbacks_.erase(it);
+        } else {
+            ++it;
+        }
+    }
+    lock.unlock();
+
+    // adjusts uevent / wakealarm periods
+    HalHealthLoop::OnHealthInfoChanged(health_info);
+}
+
+void BinderHealth::serviceDied(uint64_t /* cookie */, const wp<IBase>& who) {
+    (void)unregisterCallbackInternal(who.promote());
+}
+
+void BinderHealth::BinderEvent(uint32_t /*epevents*/) {
+    if (binder_fd_ >= 0) {
+        handleTransportPoll(binder_fd_);
+    }
+}
+
+void BinderHealth::Init(struct healthd_config* config) {
+    // Set up epoll and get uevent / wake alarm periods
+    HalHealthLoop::Init(config);
+
+    LOG(INFO) << instance_name() << " instance initializing with healthd_config...";
+
+    binder_fd_ = setupTransportPolling();
+
+    if (binder_fd_ >= 0) {
+        auto binder_event = [](auto* health_loop, uint32_t epevents) {
+            static_cast<BinderHealth*>(health_loop)->BinderEvent(epevents);
+        };
+        if (RegisterEvent(binder_fd_, binder_event, EVENT_NO_WAKEUP_FD) != 0) {
+            PLOG(ERROR) << instance_name() << " instance: Register for binder events failed";
+        }
+    }
+
+    CHECK_EQ(registerAsService(instance_name()), android::OK)
+            << instance_name() << ": Failed to register HAL";
+
+    LOG(INFO) << instance_name() << ": Hal init done";
+}
+
+int BinderHealth::PrepareToWait(void) {
+    IPCThreadState::self()->flushCommands();
+    return HalHealthLoop::PrepareToWait();
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/HalHealthLoop.cpp b/health/utils/libhealth2impl/HalHealthLoop.cpp
new file mode 100644
index 0000000..3901a76
--- /dev/null
+++ b/health/utils/libhealth2impl/HalHealthLoop.cpp
@@ -0,0 +1,94 @@
+/*
+ * 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.
+ */
+
+#include <health2impl/HalHealthLoop.h>
+
+#include <android-base/logging.h>
+#include <hal_conversion.h>
+#include <hidl/HidlTransportSupport.h>
+#include <hwbinder/IPCThreadState.h>
+
+#include <health2impl/Health.h>
+
+using android::hardware::configureRpcThreadpool;
+using android::hardware::handleTransportPoll;
+using android::hardware::IPCThreadState;
+using android::hardware::setupTransportPolling;
+
+using android::hardware::health::V1_0::hal_conversion::convertFromHealthConfig;
+using android::hardware::health::V2_0::Result;
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+void HalHealthLoop::Init(struct healthd_config* config) {
+    // Retrieve healthd_config from the HAL.
+    service_->getHealthConfig([config](auto res, const auto& health_config) {
+        CHECK(res == Result::SUCCESS);
+
+        convertFromHealthConfig(health_config.battery, config);
+        config->boot_min_cap = health_config.bootMinCap;
+
+        // Leave screen_on empty because it is handled in GetScreenOn below.
+
+        // Leave ignorePowerSupplyNames empty because it isn't
+        // used by clients of health HAL.
+    });
+}
+
+void HalHealthLoop::Heartbeat(void) {
+    // noop
+}
+
+void HalHealthLoop::ScheduleBatteryUpdate() {
+    // ignore errors. impl may not be able to handle any callbacks, so
+    // update() may return errors.
+    Result res = service_->update();
+    if (res != Result::SUCCESS) {
+        LOG(WARNING) << "update() on the health HAL implementation failed with " << toString(res);
+    }
+
+    service_->getHealthInfo_2_1([this](auto res, const auto& health_info) {
+        CHECK(res == Result::SUCCESS)
+                << "getHealthInfo_2_1() on the health HAL implementation failed with "
+                << toString(res);
+        this->OnHealthInfoChanged(health_info);
+    });
+}
+
+int HalHealthLoop::PrepareToWait() {
+    return -1;
+}
+
+void HalHealthLoop::OnHealthInfoChanged(const HealthInfo& health_info) {
+    set_charger_online(health_info);
+    AdjustWakealarmPeriods(charger_online());
+}
+
+void HalHealthLoop::set_charger_online(const HealthInfo& health_info) {
+    const auto& props = health_info.legacy.legacy;
+    charger_online_ =
+            props.chargerAcOnline || props.chargerUsbOnline || props.chargerWirelessOnline;
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/Health.cpp b/health/utils/libhealth2impl/Health.cpp
new file mode 100644
index 0000000..f4684ae
--- /dev/null
+++ b/health/utils/libhealth2impl/Health.cpp
@@ -0,0 +1,267 @@
+/*
+ * 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.
+ */
+
+#include <health2impl/Health.h>
+
+#include <functional>
+#include <string_view>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android/hardware/health/1.0/types.h>
+#include <android/hardware/health/2.0/IHealthInfoCallback.h>
+#include <android/hardware/health/2.0/types.h>
+#include <android/hardware/health/2.1/IHealthInfoCallback.h>
+#include <hal_conversion.h>
+#include <healthd/healthd.h>
+#include <hidl/HidlTransportSupport.h>
+#include <hwbinder/IPCThreadState.h>
+
+#include <health2impl/Callback.h>
+#include <health2impl/HalHealthLoop.h>
+
+using android::hardware::health::V1_0::BatteryStatus;
+using android::hardware::health::V1_0::toString;
+using android::hardware::health::V1_0::hal_conversion::convertFromHealthInfo;
+using android::hardware::health::V1_0::hal_conversion::convertToHealthConfig;
+using android::hardware::health::V1_0::hal_conversion::convertToHealthInfo;
+using android::hardware::health::V2_0::Result;
+using android::hardware::health::V2_1::IHealth;
+
+using ScreenOn = decltype(healthd_config::screen_on);
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+/*
+// If you need to call healthd_board_init, construct the Health instance with
+// the healthd_config after calling healthd_board_init:
+struct healthd_config* init_config(struct healthd_config* config) {
+    healthd_board_init(config);
+    return config;
+}
+class MyHealth : public Health {
+    MyHealth(struct healthd_config* config) :
+        Health(init_config(config)) {}
+};
+*/
+
+Health::Health(std::unique_ptr<healthd_config>&& config) : healthd_config_(std::move(config)) {
+    battery_monitor_.init(healthd_config_.get());
+}
+
+//
+// Callbacks are not supported by the passthrough implementation.
+//
+
+Return<Result> Health::registerCallback(const sp<V2_0::IHealthInfoCallback>&) {
+    return Result::NOT_SUPPORTED;
+}
+
+Return<Result> Health::unregisterCallback(const sp<V2_0::IHealthInfoCallback>&) {
+    return Result::NOT_SUPPORTED;
+}
+
+Return<Result> Health::update() {
+    Result result = Result::UNKNOWN;
+    getHealthInfo_2_1([&](auto res, const auto& /* health_info */) {
+        result = res;
+        if (res != Result::SUCCESS) {
+            LOG(ERROR) << "Cannot call getHealthInfo_2_1: " << toString(res);
+            return;
+        }
+
+        battery_monitor_.logValues();
+    });
+    return result;
+}
+
+//
+// Getters.
+//
+
+template <typename T>
+static Return<void> GetProperty(BatteryMonitor* monitor, int id, T defaultValue,
+                                const std::function<void(Result, T)>& callback) {
+    struct BatteryProperty prop;
+    T ret = defaultValue;
+    Result result = Result::SUCCESS;
+    status_t err = monitor->getProperty(static_cast<int>(id), &prop);
+    if (err != OK) {
+        LOG(DEBUG) << "getProperty(" << id << ")"
+                   << " fails: (" << err << ") " << strerror(-err);
+    } else {
+        ret = static_cast<T>(prop.valueInt64);
+    }
+    switch (err) {
+        case OK:
+            result = Result::SUCCESS;
+            break;
+        case NAME_NOT_FOUND:
+            result = Result::NOT_SUPPORTED;
+            break;
+        default:
+            result = Result::UNKNOWN;
+            break;
+    }
+    callback(result, static_cast<T>(ret));
+    return Void();
+}
+
+Return<void> Health::getChargeCounter(getChargeCounter_cb _hidl_cb) {
+    return GetProperty<int32_t>(&battery_monitor_, BATTERY_PROP_CHARGE_COUNTER, 0, _hidl_cb);
+}
+
+Return<void> Health::getCurrentNow(getCurrentNow_cb _hidl_cb) {
+    return GetProperty<int32_t>(&battery_monitor_, BATTERY_PROP_CURRENT_NOW, 0, _hidl_cb);
+}
+
+Return<void> Health::getCurrentAverage(getCurrentAverage_cb _hidl_cb) {
+    return GetProperty<int32_t>(&battery_monitor_, BATTERY_PROP_CURRENT_AVG, 0, _hidl_cb);
+}
+
+Return<void> Health::getCapacity(getCapacity_cb _hidl_cb) {
+    return GetProperty<int32_t>(&battery_monitor_, BATTERY_PROP_CAPACITY, 0, _hidl_cb);
+}
+
+Return<void> Health::getEnergyCounter(getEnergyCounter_cb _hidl_cb) {
+    return GetProperty<int64_t>(&battery_monitor_, BATTERY_PROP_ENERGY_COUNTER, 0, _hidl_cb);
+}
+
+Return<void> Health::getChargeStatus(getChargeStatus_cb _hidl_cb) {
+    return GetProperty(&battery_monitor_, BATTERY_PROP_BATTERY_STATUS, BatteryStatus::UNKNOWN,
+                       _hidl_cb);
+}
+
+Return<void> Health::getStorageInfo(getStorageInfo_cb _hidl_cb) {
+    // This implementation does not support StorageInfo. An implementation may extend this
+    // class and override this function to support storage info.
+    _hidl_cb(Result::NOT_SUPPORTED, {});
+    return Void();
+}
+
+Return<void> Health::getDiskStats(getDiskStats_cb _hidl_cb) {
+    // This implementation does not support DiskStats. An implementation may extend this
+    // class and override this function to support disk stats.
+    _hidl_cb(Result::NOT_SUPPORTED, {});
+    return Void();
+}
+
+template <typename T, typename Method>
+static inline void GetHealthInfoField(Health* service, Method func, T* out) {
+    *out = T{};
+    std::invoke(func, service, [out](Result result, const T& value) {
+        if (result == Result::SUCCESS) *out = value;
+    });
+}
+
+Return<void> Health::getHealthInfo(getHealthInfo_cb _hidl_cb) {
+    return getHealthInfo_2_1(
+            [&](auto res, const auto& health_info) { _hidl_cb(res, health_info.legacy); });
+}
+
+Return<void> Health::getHealthInfo_2_1(getHealthInfo_2_1_cb _hidl_cb) {
+    battery_monitor_.updateValues();
+
+    HealthInfo health_info = battery_monitor_.getHealthInfo_2_1();
+
+    // Fill in storage infos; these aren't retrieved by BatteryMonitor.
+    GetHealthInfoField(this, &Health::getStorageInfo, &health_info.legacy.storageInfos);
+    GetHealthInfoField(this, &Health::getDiskStats, &health_info.legacy.diskStats);
+
+    // A subclass may want to update health info struct before returning it.
+    UpdateHealthInfo(&health_info);
+
+    _hidl_cb(Result::SUCCESS, health_info);
+    return Void();
+}
+
+Return<void> Health::debug(const hidl_handle& handle, const hidl_vec<hidl_string>&) {
+    if (handle == nullptr || handle->numFds == 0) {
+        return Void();
+    }
+
+    int fd = handle->data[0];
+    battery_monitor_.dumpState(fd);
+    getHealthInfo_2_1([fd](auto res, const auto& info) {
+        android::base::WriteStringToFd("\ngetHealthInfo -> ", fd);
+        if (res == Result::SUCCESS) {
+            android::base::WriteStringToFd(toString(info), fd);
+        } else {
+            android::base::WriteStringToFd(toString(res), fd);
+        }
+        android::base::WriteStringToFd("\n", fd);
+    });
+
+    fsync(fd);
+    return Void();
+}
+
+Return<void> Health::getHealthConfig(getHealthConfig_cb _hidl_cb) {
+    HealthConfig config = {};
+    convertToHealthConfig(healthd_config_.get(), config.battery);
+    config.bootMinCap = static_cast<int32_t>(healthd_config_->boot_min_cap);
+
+    _hidl_cb(Result::SUCCESS, config);
+    return Void();
+}
+
+Return<void> Health::shouldKeepScreenOn(shouldKeepScreenOn_cb _hidl_cb) {
+    if (!healthd_config_->screen_on) {
+        _hidl_cb(Result::NOT_SUPPORTED, true);
+        return Void();
+    }
+
+    Result returned_result = Result::UNKNOWN;
+    bool screen_on = true;
+    getHealthInfo_2_1([&](auto res, const auto& health_info) {
+        returned_result = res;
+        if (returned_result != Result::SUCCESS) return;
+
+        struct BatteryProperties props = {};
+        V1_0::hal_conversion::convertFromHealthInfo(health_info.legacy.legacy, &props);
+        screen_on = healthd_config_->screen_on(&props);
+    });
+    _hidl_cb(returned_result, screen_on);
+    return Void();
+}
+
+//
+// Subclass helpers / overrides
+//
+
+void Health::UpdateHealthInfo(HealthInfo* /* health_info */) {
+    /*
+        // Sample code for a subclass to implement this:
+        // If you need to modify values (e.g. batteryChargeTimeToFullNowSeconds), do it here.
+        health_info->batteryChargeTimeToFullNowSeconds = calculate_charge_time_seconds();
+
+        // If you need to call healthd_board_battery_update:
+        struct BatteryProperties props;
+        convertFromHealthInfo(health_info.legacy.legacy, &props);
+        healthd_board_battery_update(&props);
+        convertToHealthInfo(&props, health_info.legacy.legacy);
+    */
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/include/health2impl/BinderHealth.h b/health/utils/libhealth2impl/include/health2impl/BinderHealth.h
new file mode 100644
index 0000000..1da5bd1
--- /dev/null
+++ b/health/utils/libhealth2impl/include/health2impl/BinderHealth.h
@@ -0,0 +1,111 @@
+/*
+ * 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-base/unique_fd.h>
+#include <android/hardware/health/2.1/IHealth.h>
+#include <healthd/healthd.h>
+
+#include <health2impl/Callback.h>
+#include <health2impl/HalHealthLoop.h>
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+// binderized health HAL implementation.
+class BinderHealth : public HalHealthLoop, public IHealth, public hidl_death_recipient {
+  public:
+    // |impl| should be the passthrough implementation.
+    BinderHealth(const std::string& name, const sp<IHealth>& impl);
+
+    // Methods from ::android::hardware::health::V2_0::IHealth follow.
+    Return<::android::hardware::health::V2_0::Result> registerCallback(
+            const sp<::android::hardware::health::V2_0::IHealthInfoCallback>& callback) override;
+    Return<::android::hardware::health::V2_0::Result> unregisterCallback(
+            const sp<::android::hardware::health::V2_0::IHealthInfoCallback>& callback) override;
+    Return<::android::hardware::health::V2_0::Result> update() override;
+    Return<void> getChargeCounter(getChargeCounter_cb _hidl_cb) override {
+        return service()->getChargeCounter(_hidl_cb);
+    }
+    Return<void> getCurrentNow(getCurrentNow_cb _hidl_cb) override {
+        return service()->getCurrentNow(_hidl_cb);
+    }
+    Return<void> getCurrentAverage(getCurrentAverage_cb _hidl_cb) override {
+        return service()->getCurrentAverage(_hidl_cb);
+    }
+    Return<void> getCapacity(getCapacity_cb _hidl_cb) override {
+        return service()->getCapacity(_hidl_cb);
+    }
+    Return<void> getEnergyCounter(getEnergyCounter_cb _hidl_cb) override {
+        return service()->getEnergyCounter(_hidl_cb);
+    }
+    Return<void> getChargeStatus(getChargeStatus_cb _hidl_cb) override {
+        return service()->getChargeStatus(_hidl_cb);
+    }
+    Return<void> getStorageInfo(getStorageInfo_cb _hidl_cb) override {
+        return service()->getStorageInfo(_hidl_cb);
+    }
+    Return<void> getDiskStats(getDiskStats_cb _hidl_cb) override {
+        return service()->getDiskStats(_hidl_cb);
+    }
+    Return<void> getHealthInfo(getHealthInfo_cb _hidl_cb) override {
+        return service()->getHealthInfo(_hidl_cb);
+    }
+
+    // Methods from ::android::hardware::health::V2_1::IHealth follow.
+    Return<void> getHealthConfig(getHealthConfig_cb _hidl_cb) override {
+        return service()->getHealthConfig(_hidl_cb);
+    }
+    Return<void> getHealthInfo_2_1(getHealthInfo_2_1_cb _hidl_cb) override {
+        return service()->getHealthInfo_2_1(_hidl_cb);
+    }
+    Return<void> shouldKeepScreenOn(shouldKeepScreenOn_cb _hidl_cb) override {
+        return service()->shouldKeepScreenOn(_hidl_cb);
+    }
+
+    // Methods from ::android::hidl::base::V1_0::IBase follow.
+    Return<void> debug(const hidl_handle& fd, const hidl_vec<hidl_string>& args) override {
+        return service()->debug(fd, args);
+    }
+
+    // hidl_death_recipient implementation.
+    void serviceDied(uint64_t cookie, const wp<IBase>& who) override;
+
+    // Called by BinderHealthCallback.
+    void OnHealthInfoChanged(const HealthInfo& health_info) override;
+
+  protected:
+    void Init(struct healthd_config* config) override;
+    int PrepareToWait() override;
+    // A subclass may override this if it wants to handle binder events differently.
+    virtual void BinderEvent(uint32_t epevents);
+
+  private:
+    bool unregisterCallbackInternal(const sp<IBase>& callback);
+    int binder_fd_ = -1;
+    std::mutex callbacks_lock_;
+    std::vector<std::unique_ptr<Callback>> callbacks_;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/include/health2impl/Callback.h b/health/utils/libhealth2impl/include/health2impl/Callback.h
new file mode 100644
index 0000000..a30480b
--- /dev/null
+++ b/health/utils/libhealth2impl/include/health2impl/Callback.h
@@ -0,0 +1,73 @@
+/*
+ * 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/health/2.1/IHealth.h>
+#include <android/hardware/health/2.1/IHealthInfoCallback.h>
+
+using ::android::sp;
+using ::android::hardware::Return;
+using ::android::hidl::base::V1_0::IBase;
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+// Wraps an IHealthInfoCallback.
+class Callback {
+  public:
+    virtual ~Callback() {}
+    virtual Return<void> Notify(const HealthInfo&) = 0;
+    virtual sp<IBase> Get() = 0;
+};
+
+class Callback_2_0 : public Callback {
+  public:
+    Callback_2_0(const sp<V2_0::IHealthInfoCallback>& callback) : callback_(callback) {}
+    Return<void> Notify(const HealthInfo& info) override {
+        return callback_->healthInfoChanged(info.legacy);
+    }
+    sp<IBase> Get() override { return callback_; }
+
+  private:
+    sp<V2_0::IHealthInfoCallback> callback_;
+};
+
+class Callback_2_1 : public Callback {
+  public:
+    Callback_2_1(const sp<IHealthInfoCallback>& callback) : callback_(callback) {}
+    Return<void> Notify(const HealthInfo& info) override {
+        return callback_->healthInfoChanged_2_1(info);
+    }
+    sp<IBase> Get() override { return callback_; }
+
+  private:
+    sp<IHealthInfoCallback> callback_;
+};
+
+inline std::unique_ptr<Callback> Wrap(const sp<V2_0::IHealthInfoCallback>& callback_2_0) {
+    auto callback_2_1 = IHealthInfoCallback::castFrom(callback_2_0).withDefault(nullptr);
+    if (callback_2_1) return std::make_unique<Callback_2_1>(callback_2_1);
+    return std::make_unique<Callback_2_0>(callback_2_0);
+}
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/include/health2impl/HalHealthLoop.h b/health/utils/libhealth2impl/include/health2impl/HalHealthLoop.h
new file mode 100644
index 0000000..d9b5580
--- /dev/null
+++ b/health/utils/libhealth2impl/include/health2impl/HalHealthLoop.h
@@ -0,0 +1,67 @@
+/*
+ * 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 <optional>
+
+#include <android/hardware/health/2.1/IHealth.h>
+#include <health/HealthLoop.h>
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+// An implementation of HealthLoop for using a given health HAL. This is useful
+// for services that opens the passthrough implementation and starts the HealthLoop
+// to periodically poll data from the implementation.
+class HalHealthLoop : public HealthLoop {
+  public:
+    HalHealthLoop(const std::string& name, const sp<IHealth>& service)
+        : instance_name_(name), service_(service) {}
+
+  protected:
+    virtual void Init(struct healthd_config* config) override;
+    virtual void Heartbeat() override;
+    virtual int PrepareToWait() override;
+    virtual void ScheduleBatteryUpdate() override;
+
+    // HealthLoop periodically calls ScheduleBatteryUpdate, which calls
+    // OnHealthInfoChanged callback. A client can override this function to
+    // broadcast the health_info to interested listeners. By default, this
+    // adjust uevents / wakealarm periods.
+    virtual void OnHealthInfoChanged(const HealthInfo& health_info);
+
+    const std::string& instance_name() const { return instance_name_; }
+    const sp<IHealth>& service() const { return service_; }
+    bool charger_online() const { return charger_online_; }
+
+    // Helpers for subclasses to implement OnHealthInfoChanged.
+    void set_charger_online(const HealthInfo& health_info);
+
+  private:
+    const std::string& instance_name_;
+    sp<IHealth> service_;
+    bool charger_online_ = false;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/health/utils/libhealth2impl/include/health2impl/Health.h b/health/utils/libhealth2impl/include/health2impl/Health.h
new file mode 100644
index 0000000..853b0cd
--- /dev/null
+++ b/health/utils/libhealth2impl/include/health2impl/Health.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 <memory>
+#include <mutex>
+#include <vector>
+
+#include <android-base/unique_fd.h>
+#include <android/hardware/health/2.1/IHealth.h>
+#include <healthd/BatteryMonitor.h>
+#include <hidl/Status.h>
+
+#include <health2impl/Callback.h>
+
+using ::android::sp;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hidl::base::V1_0::IBase;
+
+namespace android {
+namespace hardware {
+namespace health {
+namespace V2_1 {
+namespace implementation {
+
+class Health : public IHealth {
+  public:
+    Health(std::unique_ptr<healthd_config>&& config);
+
+    // Methods from ::android::hardware::health::V2_0::IHealth follow.
+    Return<::android::hardware::health::V2_0::Result> registerCallback(
+            const sp<::android::hardware::health::V2_0::IHealthInfoCallback>& callback) override;
+    Return<::android::hardware::health::V2_0::Result> unregisterCallback(
+            const sp<::android::hardware::health::V2_0::IHealthInfoCallback>& callback) override;
+    Return<::android::hardware::health::V2_0::Result> update() override;
+    Return<void> getChargeCounter(getChargeCounter_cb _hidl_cb) override;
+    Return<void> getCurrentNow(getCurrentNow_cb _hidl_cb) override;
+    Return<void> getCurrentAverage(getCurrentAverage_cb _hidl_cb) override;
+    Return<void> getCapacity(getCapacity_cb _hidl_cb) override;
+    Return<void> getEnergyCounter(getEnergyCounter_cb _hidl_cb) override;
+    Return<void> getChargeStatus(getChargeStatus_cb _hidl_cb) override;
+    Return<void> getStorageInfo(getStorageInfo_cb _hidl_cb) override;
+    Return<void> getDiskStats(getDiskStats_cb _hidl_cb) override;
+    Return<void> getHealthInfo(getHealthInfo_cb _hidl_cb) override;
+
+    // Methods from ::android::hardware::health::V2_1::IHealth follow.
+    Return<void> getHealthConfig(getHealthConfig_cb _hidl_cb) override;
+    Return<void> getHealthInfo_2_1(getHealthInfo_2_1_cb _hidl_cb) override;
+    Return<void> shouldKeepScreenOn(shouldKeepScreenOn_cb _hidl_cb) override;
+
+    // Methods from ::android::hidl::base::V1_0::IBase follow.
+    Return<void> debug(const hidl_handle& fd, const hidl_vec<hidl_string>& args) override;
+
+  protected:
+    // A subclass can override this to modify any health info object before
+    // returning to clients. This is similar to healthd_board_battery_update().
+    // By default, it does nothing.
+    virtual void UpdateHealthInfo(HealthInfo* health_info);
+
+  private:
+    bool unregisterCallbackInternal(const sp<IBase>& callback);
+
+    BatteryMonitor battery_monitor_;
+    std::unique_ptr<healthd_config> healthd_config_;
+
+    std::mutex callbacks_lock_;
+    std::vector<std::unique_ptr<Callback>> callbacks_;
+};
+
+}  // namespace implementation
+}  // namespace V2_1
+}  // namespace health
+}  // namespace hardware
+}  // namespace android
diff --git a/ir/1.0/vts/functional/Android.bp b/ir/1.0/vts/functional/Android.bp
index f5c9d61..f9edebd 100644
--- a/ir/1.0/vts/functional/Android.bp
+++ b/ir/1.0/vts/functional/Android.bp
@@ -21,5 +21,5 @@
     static_libs: [
         "android.hardware.ir@1.0",
     ],
-    test_suites: ["general-tests"],
+    test_suites: ["general-tests", "vts-core"],
 }
diff --git a/ir/1.0/vts/functional/VtsHalIrV1_0TargetTest.cpp b/ir/1.0/vts/functional/VtsHalIrV1_0TargetTest.cpp
index 5fd2dd4..a5dbdcc 100644
--- a/ir/1.0/vts/functional/VtsHalIrV1_0TargetTest.cpp
+++ b/ir/1.0/vts/functional/VtsHalIrV1_0TargetTest.cpp
@@ -21,8 +21,9 @@
 #include <android/hardware/ir/1.0/IConsumerIr.h>
 #include <android/hardware/ir/1.0/types.h>
 
-#include <VtsHalHidlTargetTestBase.h>
-#include <VtsHalHidlTargetTestEnvBase.h>
+#include <gtest/gtest.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
 #include <algorithm>
 
 using ::android::hardware::ir::V1_0::IConsumerIr;
@@ -31,26 +32,10 @@
 using ::android::hardware::Return;
 using ::android::sp;
 
-// Test environment for Ir
-class ConsumerIrHidlEnvironment : public ::testing::VtsHalHidlTargetTestEnvBase {
- public:
-  // get the test environment singleton
-  static ConsumerIrHidlEnvironment* Instance() {
-    static ConsumerIrHidlEnvironment* instance = new ConsumerIrHidlEnvironment;
-    return instance;
-  }
-
-  virtual void registerTestServices() override { registerTestService<IConsumerIr>(); }
- private:
-  ConsumerIrHidlEnvironment() {}
-};
-
-// The main test class for IR HIDL HAL.
-class ConsumerIrHidlTest : public ::testing::VtsHalHidlTargetTestBase {
+class ConsumerIrHidlTest : public ::testing::TestWithParam<std::string> {
  public:
   virtual void SetUp() override {
-    ir = ::testing::VtsHalHidlTargetTestBase::getService<IConsumerIr>(
-      ConsumerIrHidlEnvironment::Instance()->getServiceName<IConsumerIr>());
+    ir = IConsumerIr::getService(GetParam());
     ASSERT_NE(ir, nullptr);
   }
 
@@ -60,7 +45,7 @@
 };
 
 // Test transmit() for the min and max frequency of every available range
-TEST_F(ConsumerIrHidlTest, TransmitTest) {
+TEST_P(ConsumerIrHidlTest, TransmitTest) {
   bool success;
   hidl_vec<ConsumerIrFreqRange> ranges;
   auto cb = [&](bool s, hidl_vec<ConsumerIrFreqRange> v) {
@@ -84,7 +69,7 @@
 }
 
 // Test transmit() when called with invalid frequencies
-TEST_F(ConsumerIrHidlTest, BadFreqTest) {
+TEST_P(ConsumerIrHidlTest, BadFreqTest) {
   uint32_t len = 16;
   hidl_vec<int32_t> vec;
   vec.resize(len);
@@ -92,11 +77,7 @@
   EXPECT_FALSE(ir->transmit(-1, vec));
 }
 
-int main(int argc, char **argv) {
-  ::testing::AddGlobalTestEnvironment(ConsumerIrHidlEnvironment::Instance());
-  ::testing::InitGoogleTest(&argc, argv);
-  ConsumerIrHidlEnvironment::Instance()->init(&argc, argv);
-  int status = RUN_ALL_TESTS();
-  LOG(INFO) << "Test result = " << status;
-  return status;
-}
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, ConsumerIrHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IConsumerIr::descriptor)),
+        android::hardware::PrintInstanceNameToString);
diff --git a/neuralnetworks/1.3/vts/functional/Android.bp b/neuralnetworks/1.3/vts/functional/Android.bp
index 90ce852..0f2720e 100644
--- a/neuralnetworks/1.3/vts/functional/Android.bp
+++ b/neuralnetworks/1.3/vts/functional/Android.bp
@@ -15,7 +15,7 @@
 //
 
 cc_test {
-    name: "VtsHalNeuralNetworksV1_3TargetTest",
+    name: "VtsHalNeuralnetworksV1_3TargetTest",
     defaults: ["VtsHalTargetTestDefaults"],
     srcs: [
         "BasicTests.cpp",
diff --git a/neuralnetworks/TEST_MAPPING b/neuralnetworks/TEST_MAPPING
index 421922a..bbf34f7 100644
--- a/neuralnetworks/TEST_MAPPING
+++ b/neuralnetworks/TEST_MAPPING
@@ -7,7 +7,7 @@
           // Just use sample-all driver for presubmit tests for faster results.
           // The other sample drivers (fast-float, quant, etc.) are subsets of
           // sample-all.
-          "native-test-flag": "--gtest_filter=*sample_all*"
+          "include-filter": "*sample_all*"
         }
       ]
     },
@@ -18,7 +18,7 @@
           // Just use sample-all driver for presubmit tests for faster results.
           // The other sample drivers (fast-float, quant, etc.) are subsets of
           // sample-all.
-          "native-test-flag": "--gtest_filter=*sample_all*"
+          "include-filter": "*sample_all*"
         }
       ]
     },
@@ -29,7 +29,18 @@
           // Just use sample-all driver for presubmit tests for faster results.
           // The other sample drivers (fast-float, quant, etc.) are subsets of
           // sample-all.
-          "native-test-flag": "--gtest_filter=*sample_all*"
+          "include-filter": "*sample_all*"
+        }
+      ]
+    },
+    {
+      "name": "VtsHalNeuralnetworksV1_3TargetTest",
+      "options": [
+        {
+          // Just use sample-all driver for presubmit tests for faster results.
+          // The other sample drivers (fast-float, quant, etc.) are subsets of
+          // sample-all.
+          "include-filter": "*sample_all*"
         }
       ]
     }
diff --git a/vr/1.0/vts/functional/Android.bp b/vr/1.0/vts/functional/Android.bp
index 958cce7..bd0336c 100644
--- a/vr/1.0/vts/functional/Android.bp
+++ b/vr/1.0/vts/functional/Android.bp
@@ -19,5 +19,5 @@
     defaults: ["VtsHalTargetTestDefaults"],
     srcs: ["VtsHalVrV1_0TargetTest.cpp"],
     static_libs: ["android.hardware.vr@1.0"],
-    test_suites: ["general-tests"],
+    test_suites: ["general-tests", "vts-core"],
 }
diff --git a/vr/1.0/vts/functional/VtsHalVrV1_0TargetTest.cpp b/vr/1.0/vts/functional/VtsHalVrV1_0TargetTest.cpp
index b165613..c08e5ca 100644
--- a/vr/1.0/vts/functional/VtsHalVrV1_0TargetTest.cpp
+++ b/vr/1.0/vts/functional/VtsHalVrV1_0TargetTest.cpp
@@ -15,11 +15,12 @@
  */
 
 #define LOG_TAG "vr_hidl_hal_test"
-#include <VtsHalHidlTargetTestBase.h>
-#include <VtsHalHidlTargetTestEnvBase.h>
 #include <android-base/logging.h>
 #include <android/hardware/vr/1.0/IVr.h>
+#include <gtest/gtest.h>
 #include <hardware/vr.h>
+#include <hidl/GtestPrinter.h>
+#include <hidl/ServiceManagement.h>
 #include <log/log.h>
 
 using ::android::hardware::vr::V1_0::IVr;
@@ -27,24 +28,11 @@
 using ::android::hardware::Void;
 using ::android::sp;
 
-// Test environment for Vr HIDL HAL.
-class VrHidlEnvironment : public ::testing::VtsHalHidlTargetTestEnvBase {
- public:
-  // get the test environment singleton
-  static VrHidlEnvironment* Instance() {
-    static VrHidlEnvironment* instance = new VrHidlEnvironment;
-    return instance;
-  }
-
-  virtual void registerTestServices() override { registerTestService<IVr>(); }
-};
-
 // The main test class for VR HIDL HAL.
-class VrHidlTest : public ::testing::VtsHalHidlTargetTestBase {
+class VrHidlTest : public ::testing::TestWithParam<std::string> {
  public:
   void SetUp() override {
-    vr = ::testing::VtsHalHidlTargetTestBase::getService<IVr>(
-        VrHidlEnvironment::Instance()->getServiceName<IVr>());
+    vr = IVr::getService(GetParam());
     ASSERT_NE(vr, nullptr);
   }
 
@@ -54,19 +42,19 @@
 };
 
 // Sanity check that Vr::init does not crash.
-TEST_F(VrHidlTest, Init) {
+TEST_P(VrHidlTest, Init) {
   EXPECT_TRUE(vr->init().isOk());
 }
 
 // Sanity check Vr::setVrMode is able to enable and disable VR mode.
-TEST_F(VrHidlTest, SetVrMode) {
+TEST_P(VrHidlTest, SetVrMode) {
   EXPECT_TRUE(vr->init().isOk());
   EXPECT_TRUE(vr->setVrMode(true).isOk());
   EXPECT_TRUE(vr->setVrMode(false).isOk());
 }
 
 // Sanity check that Vr::init and Vr::setVrMode can be used in any order.
-TEST_F(VrHidlTest, ReInit) {
+TEST_P(VrHidlTest, ReInit) {
   EXPECT_TRUE(vr->init().isOk());
   EXPECT_TRUE(vr->setVrMode(true).isOk());
   EXPECT_TRUE(vr->init().isOk());
@@ -75,11 +63,8 @@
   EXPECT_TRUE(vr->setVrMode(false).isOk());
 }
 
-int main(int argc, char **argv) {
-  ::testing::AddGlobalTestEnvironment(VrHidlEnvironment::Instance());
-  ::testing::InitGoogleTest(&argc, argv);
-  VrHidlEnvironment::Instance()->init(&argc, argv);
-  int status = RUN_ALL_TESTS();
-  ALOGI("Test result = %d", status);
-  return status;
-}
+INSTANTIATE_TEST_SUITE_P(
+        PerInstance, VrHidlTest,
+        testing::ValuesIn(android::hardware::getAllHalInstanceNames(IVr::descriptor)),
+        android::hardware::PrintInstanceNameToString);
+