diff --git a/graphics/composer/2.1/utils/passthrough/Android.bp b/graphics/composer/2.1/utils/passthrough/Android.bp
new file mode 100644
index 0000000..4d3c976
--- /dev/null
+++ b/graphics/composer/2.1/utils/passthrough/Android.bp
@@ -0,0 +1,22 @@
+cc_library_headers {
+    name: "android.hardware.graphics.composer@2.1-passthrough",
+    defaults: ["hidl_defaults"],
+    vendor: true,
+    shared_libs: [
+        "libhardware",
+        "libhwc2on1adapter",
+        "libhwc2onfbadapter",
+    ],
+    export_shared_lib_headers: [
+        "libhardware",
+        "libhwc2on1adapter",
+        "libhwc2onfbadapter",
+    ],
+    header_libs: [
+        "android.hardware.graphics.composer@2.1-hal",
+    ],
+    export_header_lib_headers: [
+        "android.hardware.graphics.composer@2.1-hal",
+    ],
+    export_include_dirs: ["include"],
+}
diff --git a/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcHal.h b/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcHal.h
new file mode 100644
index 0000000..964e75b
--- /dev/null
+++ b/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcHal.h
@@ -0,0 +1,670 @@
+/*
+ * Copyright 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#ifndef LOG_TAG
+#warning "HwcHal.h included without LOG_TAG"
+#endif
+
+#include <atomic>
+#include <cstring>  // for strerror
+#include <type_traits>
+#include <unordered_set>
+#include <vector>
+
+#include <android/hardware/graphics/composer/2.1/IComposer.h>
+#include <composer-hal/2.1/ComposerHal.h>
+#define HWC2_INCLUDE_STRINGIFICATION
+#define HWC2_USE_CPP11
+#include <hardware/hwcomposer2.h>
+#undef HWC2_INCLUDE_STRINGIFICATION
+#undef HWC2_USE_CPP11
+#include <log/log.h>
+
+namespace android {
+namespace hardware {
+namespace graphics {
+namespace composer {
+namespace V2_1 {
+namespace passthrough {
+
+namespace detail {
+
+using android::hardware::graphics::common::V1_0::ColorMode;
+using android::hardware::graphics::common::V1_0::ColorTransform;
+using android::hardware::graphics::common::V1_0::Dataspace;
+using android::hardware::graphics::common::V1_0::Hdr;
+using android::hardware::graphics::common::V1_0::PixelFormat;
+using android::hardware::graphics::common::V1_0::Transform;
+
+// HwcHalImpl implements V2_*::hal::ComposerHal on top of hwcomposer2
+template <typename Hal>
+class HwcHalImpl : public Hal {
+   public:
+    virtual ~HwcHalImpl() {
+        if (mDevice) {
+            hwc2_close(mDevice);
+        }
+    }
+
+    bool initWithModule(const hw_module_t* module) {
+        hwc2_device_t* device;
+        int result = hwc2_open(module, &device);
+        if (result) {
+            ALOGE("failed to open hwcomposer2 device: %s", strerror(-result));
+            return false;
+        }
+
+        return initWithDevice(std::move(device), true);
+    }
+
+    bool initWithDevice(hwc2_device_t* device, bool requireReliablePresentFence) {
+        // we own the device from this point on
+        mDevice = device;
+
+        initCapabilities();
+        if (requireReliablePresentFence &&
+            hasCapability(HWC2_CAPABILITY_PRESENT_FENCE_IS_NOT_RELIABLE)) {
+            ALOGE("present fence must be reliable");
+            mDevice->common.close(&mDevice->common);
+            mDevice = nullptr;
+            return false;
+        }
+
+        if (!initDispatch()) {
+            mDevice->common.close(&mDevice->common);
+            mDevice = nullptr;
+            return false;
+        }
+
+        return true;
+    }
+
+    bool hasCapability(hwc2_capability_t capability) override {
+        return (mCapabilities.count(capability) > 0);
+    }
+
+    std::string dumpDebugInfo() override {
+        uint32_t len = 0;
+        mDispatch.dump(mDevice, &len, nullptr);
+
+        std::vector<char> buf(len + 1);
+        mDispatch.dump(mDevice, &len, buf.data());
+        buf.resize(len + 1);
+        buf[len] = '\0';
+
+        return buf.data();
+    }
+
+    void registerEventCallback(hal::ComposerHal::EventCallback* callback) override {
+        mMustValidateDisplay = true;
+        mEventCallback = 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));
+    }
+
+    void unregisterEventCallback() 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);
+
+        mEventCallback = nullptr;
+    }
+
+    uint32_t getMaxVirtualDisplayCount() override {
+        return mDispatch.getMaxVirtualDisplayCount(mDevice);
+    }
+
+    Error createVirtualDisplay(uint32_t width, uint32_t height, PixelFormat* format,
+                               Display* outDisplay) override {
+        int32_t hwc_format = static_cast<int32_t>(*format);
+        int32_t err =
+            mDispatch.createVirtualDisplay(mDevice, width, height, &hwc_format, outDisplay);
+        *format = static_cast<PixelFormat>(hwc_format);
+
+        return static_cast<Error>(err);
+    }
+
+    Error destroyVirtualDisplay(Display display) override {
+        int32_t err = mDispatch.destroyVirtualDisplay(mDevice, display);
+        return static_cast<Error>(err);
+    }
+
+    Error createLayer(Display display, Layer* outLayer) override {
+        int32_t err = mDispatch.createLayer(mDevice, display, outLayer);
+        return static_cast<Error>(err);
+    }
+
+    Error destroyLayer(Display display, Layer layer) override {
+        int32_t err = mDispatch.destroyLayer(mDevice, display, layer);
+        return static_cast<Error>(err);
+    }
+
+    Error getActiveConfig(Display display, Config* outConfig) override {
+        int32_t err = mDispatch.getActiveConfig(mDevice, display, outConfig);
+        return static_cast<Error>(err);
+    }
+
+    Error getClientTargetSupport(Display display, uint32_t width, uint32_t height,
+                                 PixelFormat format, Dataspace dataspace) override {
+        int32_t err = mDispatch.getClientTargetSupport(mDevice, display, width, height,
+                                                       static_cast<int32_t>(format),
+                                                       static_cast<int32_t>(dataspace));
+        return static_cast<Error>(err);
+    }
+
+    Error getColorModes(Display display, hidl_vec<ColorMode>* outModes) override {
+        uint32_t count = 0;
+        int32_t err = mDispatch.getColorModes(mDevice, display, &count, nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        outModes->resize(count);
+        err = mDispatch.getColorModes(
+            mDevice, display, &count,
+            reinterpret_cast<std::underlying_type<ColorMode>::type*>(outModes->data()));
+        if (err != HWC2_ERROR_NONE) {
+            *outModes = hidl_vec<ColorMode>();
+            return static_cast<Error>(err);
+        }
+
+        return Error::NONE;
+    }
+
+    Error getDisplayAttribute(Display display, Config config, IComposerClient::Attribute attribute,
+                              int32_t* outValue) override {
+        int32_t err = mDispatch.getDisplayAttribute(mDevice, display, config,
+                                                    static_cast<int32_t>(attribute), outValue);
+        return static_cast<Error>(err);
+    }
+
+    Error getDisplayConfigs(Display display, hidl_vec<Config>* outConfigs) override {
+        uint32_t count = 0;
+        int32_t err = mDispatch.getDisplayConfigs(mDevice, display, &count, nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        outConfigs->resize(count);
+        err = mDispatch.getDisplayConfigs(mDevice, display, &count, outConfigs->data());
+        if (err != HWC2_ERROR_NONE) {
+            *outConfigs = hidl_vec<Config>();
+            return static_cast<Error>(err);
+        }
+
+        return Error::NONE;
+    }
+
+    Error getDisplayName(Display display, hidl_string* outName) override {
+        uint32_t count = 0;
+        int32_t err = mDispatch.getDisplayName(mDevice, display, &count, nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        std::vector<char> buf(count + 1);
+        err = mDispatch.getDisplayName(mDevice, display, &count, buf.data());
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+        buf.resize(count + 1);
+        buf[count] = '\0';
+
+        *outName = buf.data();
+
+        return Error::NONE;
+    }
+
+    Error getDisplayType(Display display, IComposerClient::DisplayType* outType) override {
+        int32_t hwc_type = HWC2_DISPLAY_TYPE_INVALID;
+        int32_t err = mDispatch.getDisplayType(mDevice, display, &hwc_type);
+        *outType = static_cast<IComposerClient::DisplayType>(hwc_type);
+
+        return static_cast<Error>(err);
+    }
+
+    Error getDozeSupport(Display display, bool* outSupport) override {
+        int32_t hwc_support = 0;
+        int32_t err = mDispatch.getDozeSupport(mDevice, display, &hwc_support);
+        *outSupport = hwc_support;
+
+        return static_cast<Error>(err);
+    }
+
+    Error getHdrCapabilities(Display display, hidl_vec<Hdr>* outTypes, float* outMaxLuminance,
+                             float* outMaxAverageLuminance, float* outMinLuminance) override {
+        uint32_t count = 0;
+        int32_t err =
+            mDispatch.getHdrCapabilities(mDevice, display, &count, nullptr, outMaxLuminance,
+                                         outMaxAverageLuminance, outMinLuminance);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        outTypes->resize(count);
+        err = mDispatch.getHdrCapabilities(
+            mDevice, display, &count,
+            reinterpret_cast<std::underlying_type<Hdr>::type*>(outTypes->data()), outMaxLuminance,
+            outMaxAverageLuminance, outMinLuminance);
+        if (err != HWC2_ERROR_NONE) {
+            *outTypes = hidl_vec<Hdr>();
+            return static_cast<Error>(err);
+        }
+
+        return Error::NONE;
+    }
+
+    Error setActiveConfig(Display display, Config config) override {
+        int32_t err = mDispatch.setActiveConfig(mDevice, display, config);
+        return static_cast<Error>(err);
+    }
+
+    Error setColorMode(Display display, ColorMode mode) override {
+        int32_t err = mDispatch.setColorMode(mDevice, display, static_cast<int32_t>(mode));
+        return static_cast<Error>(err);
+    }
+
+    Error setPowerMode(Display display, IComposerClient::PowerMode mode) override {
+        int32_t err = mDispatch.setPowerMode(mDevice, display, static_cast<int32_t>(mode));
+        return static_cast<Error>(err);
+    }
+
+    Error setVsyncEnabled(Display display, IComposerClient::Vsync enabled) override {
+        int32_t err = mDispatch.setVsyncEnabled(mDevice, display, static_cast<int32_t>(enabled));
+        return static_cast<Error>(err);
+    }
+
+    Error setColorTransform(Display display, const float* matrix, int32_t hint) override {
+        int32_t err = mDispatch.setColorTransform(mDevice, display, matrix, hint);
+        return static_cast<Error>(err);
+    }
+
+    Error setClientTarget(Display display, buffer_handle_t target, int32_t acquireFence,
+                          int32_t dataspace, const std::vector<hwc_rect_t>& damage) override {
+        hwc_region region = {damage.size(), damage.data()};
+        int32_t err =
+            mDispatch.setClientTarget(mDevice, display, target, acquireFence, dataspace, region);
+        return static_cast<Error>(err);
+    }
+
+    Error setOutputBuffer(Display display, buffer_handle_t buffer, int32_t releaseFence) override {
+        int32_t err = mDispatch.setOutputBuffer(mDevice, display, buffer, releaseFence);
+        // unlike in setClientTarget, releaseFence is owned by us
+        if (err == HWC2_ERROR_NONE && releaseFence >= 0) {
+            close(releaseFence);
+        }
+
+        return static_cast<Error>(err);
+    }
+
+    Error validateDisplay(Display display, std::vector<Layer>* outChangedLayers,
+                          std::vector<IComposerClient::Composition>* outCompositionTypes,
+                          uint32_t* outDisplayRequestMask, std::vector<Layer>* outRequestedLayers,
+                          std::vector<uint32_t>* outRequestMasks) override {
+        uint32_t typesCount = 0;
+        uint32_t reqsCount = 0;
+        int32_t err = mDispatch.validateDisplay(mDevice, display, &typesCount, &reqsCount);
+        mMustValidateDisplay = false;
+
+        if (err != HWC2_ERROR_NONE && err != HWC2_ERROR_HAS_CHANGES) {
+            return static_cast<Error>(err);
+        }
+
+        err = mDispatch.getChangedCompositionTypes(mDevice, display, &typesCount, nullptr, nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        std::vector<Layer> changedLayers(typesCount);
+        std::vector<IComposerClient::Composition> compositionTypes(typesCount);
+        err = mDispatch.getChangedCompositionTypes(
+            mDevice, display, &typesCount, changedLayers.data(),
+            reinterpret_cast<std::underlying_type<IComposerClient::Composition>::type*>(
+                compositionTypes.data()));
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        int32_t displayReqs = 0;
+        err = mDispatch.getDisplayRequests(mDevice, display, &displayReqs, &reqsCount, nullptr,
+                                           nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        std::vector<Layer> requestedLayers(reqsCount);
+        std::vector<uint32_t> requestMasks(reqsCount);
+        err = mDispatch.getDisplayRequests(mDevice, display, &displayReqs, &reqsCount,
+                                           requestedLayers.data(),
+                                           reinterpret_cast<int32_t*>(requestMasks.data()));
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        *outChangedLayers = std::move(changedLayers);
+        *outCompositionTypes = std::move(compositionTypes);
+        *outDisplayRequestMask = displayReqs;
+        *outRequestedLayers = std::move(requestedLayers);
+        *outRequestMasks = std::move(requestMasks);
+
+        return static_cast<Error>(err);
+    }
+
+    Error acceptDisplayChanges(Display display) override {
+        int32_t err = mDispatch.acceptDisplayChanges(mDevice, display);
+        return static_cast<Error>(err);
+    }
+
+    Error presentDisplay(Display display, int32_t* outPresentFence, std::vector<Layer>* outLayers,
+                         std::vector<int32_t>* outReleaseFences) override {
+        if (mMustValidateDisplay) {
+            return Error::NOT_VALIDATED;
+        }
+
+        *outPresentFence = -1;
+        int32_t err = mDispatch.presentDisplay(mDevice, display, outPresentFence);
+        if (err != HWC2_ERROR_NONE) {
+            return static_cast<Error>(err);
+        }
+
+        uint32_t count = 0;
+        err = mDispatch.getReleaseFences(mDevice, display, &count, nullptr, nullptr);
+        if (err != HWC2_ERROR_NONE) {
+            ALOGW("failed to get release fences");
+            return Error::NONE;
+        }
+
+        outLayers->resize(count);
+        outReleaseFences->resize(count);
+        err = mDispatch.getReleaseFences(mDevice, display, &count, outLayers->data(),
+                                         outReleaseFences->data());
+        if (err != HWC2_ERROR_NONE) {
+            ALOGW("failed to get release fences");
+            outLayers->clear();
+            outReleaseFences->clear();
+            return Error::NONE;
+        }
+
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerCursorPosition(Display display, Layer layer, int32_t x, int32_t y) override {
+        int32_t err = mDispatch.setCursorPosition(mDevice, display, layer, x, y);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerBuffer(Display display, Layer layer, buffer_handle_t buffer,
+                         int32_t acquireFence) override {
+        int32_t err = mDispatch.setLayerBuffer(mDevice, display, layer, buffer, acquireFence);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerSurfaceDamage(Display display, Layer layer,
+                                const std::vector<hwc_rect_t>& damage) override {
+        hwc_region region = {damage.size(), damage.data()};
+        int32_t err = mDispatch.setLayerSurfaceDamage(mDevice, display, layer, region);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerBlendMode(Display display, Layer layer, int32_t mode) override {
+        int32_t err = mDispatch.setLayerBlendMode(mDevice, display, layer, mode);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerColor(Display display, Layer layer, IComposerClient::Color color) override {
+        hwc_color_t hwc_color{color.r, color.g, color.b, color.a};
+        int32_t err = mDispatch.setLayerColor(mDevice, display, layer, hwc_color);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerCompositionType(Display display, Layer layer, int32_t type) override {
+        int32_t err = mDispatch.setLayerCompositionType(mDevice, display, layer, type);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerDataspace(Display display, Layer layer, int32_t dataspace) override {
+        int32_t err = mDispatch.setLayerDataspace(mDevice, display, layer, dataspace);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerDisplayFrame(Display display, Layer layer, const hwc_rect_t& frame) override {
+        int32_t err = mDispatch.setLayerDisplayFrame(mDevice, display, layer, frame);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerPlaneAlpha(Display display, Layer layer, float alpha) override {
+        int32_t err = mDispatch.setLayerPlaneAlpha(mDevice, display, layer, alpha);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerSidebandStream(Display display, Layer layer, buffer_handle_t stream) override {
+        int32_t err = mDispatch.setLayerSidebandStream(mDevice, display, layer, stream);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerSourceCrop(Display display, Layer layer, const hwc_frect_t& crop) override {
+        int32_t err = mDispatch.setLayerSourceCrop(mDevice, display, layer, crop);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerTransform(Display display, Layer layer, int32_t transform) override {
+        int32_t err = mDispatch.setLayerTransform(mDevice, display, layer, transform);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerVisibleRegion(Display display, Layer layer,
+                                const std::vector<hwc_rect_t>& visible) override {
+        hwc_region_t region = {visible.size(), visible.data()};
+        int32_t err = mDispatch.setLayerVisibleRegion(mDevice, display, layer, region);
+        return static_cast<Error>(err);
+    }
+
+    Error setLayerZOrder(Display display, Layer layer, uint32_t z) override {
+        int32_t err = mDispatch.setLayerZOrder(mDevice, display, layer, z);
+        return static_cast<Error>(err);
+    }
+
+   protected:
+    virtual void initCapabilities() {
+        uint32_t count = 0;
+        mDevice->getCapabilities(mDevice, &count, nullptr);
+
+        std::vector<int32_t> caps(count);
+        mDevice->getCapabilities(mDevice, &count, caps.data());
+        caps.resize(count);
+
+        mCapabilities.reserve(count);
+        for (auto cap : caps) {
+            mCapabilities.insert(static_cast<hwc2_capability_t>(cap));
+        }
+    }
+
+    template <typename T>
+    bool initDispatch(hwc2_function_descriptor_t desc, T* outPfn) {
+        auto pfn = mDevice->getFunction(mDevice, desc);
+        if (pfn) {
+            *outPfn = reinterpret_cast<T>(pfn);
+            return true;
+        } else {
+            ALOGE("failed to get hwcomposer2 function %d", desc);
+            return false;
+        }
+    }
+
+    virtual bool initDispatch() {
+        if (!initDispatch(HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES, &mDispatch.acceptDisplayChanges) ||
+            !initDispatch(HWC2_FUNCTION_CREATE_LAYER, &mDispatch.createLayer) ||
+            !initDispatch(HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY, &mDispatch.createVirtualDisplay) ||
+            !initDispatch(HWC2_FUNCTION_DESTROY_LAYER, &mDispatch.destroyLayer) ||
+            !initDispatch(HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY,
+                          &mDispatch.destroyVirtualDisplay) ||
+            !initDispatch(HWC2_FUNCTION_DUMP, &mDispatch.dump) ||
+            !initDispatch(HWC2_FUNCTION_GET_ACTIVE_CONFIG, &mDispatch.getActiveConfig) ||
+            !initDispatch(HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES,
+                          &mDispatch.getChangedCompositionTypes) ||
+            !initDispatch(HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT,
+                          &mDispatch.getClientTargetSupport) ||
+            !initDispatch(HWC2_FUNCTION_GET_COLOR_MODES, &mDispatch.getColorModes) ||
+            !initDispatch(HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE, &mDispatch.getDisplayAttribute) ||
+            !initDispatch(HWC2_FUNCTION_GET_DISPLAY_CONFIGS, &mDispatch.getDisplayConfigs) ||
+            !initDispatch(HWC2_FUNCTION_GET_DISPLAY_NAME, &mDispatch.getDisplayName) ||
+            !initDispatch(HWC2_FUNCTION_GET_DISPLAY_REQUESTS, &mDispatch.getDisplayRequests) ||
+            !initDispatch(HWC2_FUNCTION_GET_DISPLAY_TYPE, &mDispatch.getDisplayType) ||
+            !initDispatch(HWC2_FUNCTION_GET_DOZE_SUPPORT, &mDispatch.getDozeSupport) ||
+            !initDispatch(HWC2_FUNCTION_GET_HDR_CAPABILITIES, &mDispatch.getHdrCapabilities) ||
+            !initDispatch(HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT,
+                          &mDispatch.getMaxVirtualDisplayCount) ||
+            !initDispatch(HWC2_FUNCTION_GET_RELEASE_FENCES, &mDispatch.getReleaseFences) ||
+            !initDispatch(HWC2_FUNCTION_PRESENT_DISPLAY, &mDispatch.presentDisplay) ||
+            !initDispatch(HWC2_FUNCTION_REGISTER_CALLBACK, &mDispatch.registerCallback) ||
+            !initDispatch(HWC2_FUNCTION_SET_ACTIVE_CONFIG, &mDispatch.setActiveConfig) ||
+            !initDispatch(HWC2_FUNCTION_SET_CLIENT_TARGET, &mDispatch.setClientTarget) ||
+            !initDispatch(HWC2_FUNCTION_SET_COLOR_MODE, &mDispatch.setColorMode) ||
+            !initDispatch(HWC2_FUNCTION_SET_COLOR_TRANSFORM, &mDispatch.setColorTransform) ||
+            !initDispatch(HWC2_FUNCTION_SET_CURSOR_POSITION, &mDispatch.setCursorPosition) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_BLEND_MODE, &mDispatch.setLayerBlendMode) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_BUFFER, &mDispatch.setLayerBuffer) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_COLOR, &mDispatch.setLayerColor) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE,
+                          &mDispatch.setLayerCompositionType) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_DATASPACE, &mDispatch.setLayerDataspace) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME, &mDispatch.setLayerDisplayFrame) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA, &mDispatch.setLayerPlaneAlpha)) {
+            return false;
+        }
+
+        if (hasCapability(HWC2_CAPABILITY_SIDEBAND_STREAM)) {
+            if (!initDispatch(HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM,
+                              &mDispatch.setLayerSidebandStream)) {
+                return false;
+            }
+        }
+
+        if (!initDispatch(HWC2_FUNCTION_SET_LAYER_SOURCE_CROP, &mDispatch.setLayerSourceCrop) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE,
+                          &mDispatch.setLayerSurfaceDamage) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_TRANSFORM, &mDispatch.setLayerTransform) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION,
+                          &mDispatch.setLayerVisibleRegion) ||
+            !initDispatch(HWC2_FUNCTION_SET_LAYER_Z_ORDER, &mDispatch.setLayerZOrder) ||
+            !initDispatch(HWC2_FUNCTION_SET_OUTPUT_BUFFER, &mDispatch.setOutputBuffer) ||
+            !initDispatch(HWC2_FUNCTION_SET_POWER_MODE, &mDispatch.setPowerMode) ||
+            !initDispatch(HWC2_FUNCTION_SET_VSYNC_ENABLED, &mDispatch.setVsyncEnabled) ||
+            !initDispatch(HWC2_FUNCTION_VALIDATE_DISPLAY, &mDispatch.validateDisplay)) {
+            return false;
+        }
+
+        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->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->mMustValidateDisplay = true;
+        hal->mEventCallback->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->onVsync(display, timestamp);
+    }
+
+    hwc2_device_t* mDevice = nullptr;
+
+    std::unordered_set<hwc2_capability_t> mCapabilities;
+
+    struct {
+        HWC2_PFN_ACCEPT_DISPLAY_CHANGES acceptDisplayChanges;
+        HWC2_PFN_CREATE_LAYER createLayer;
+        HWC2_PFN_CREATE_VIRTUAL_DISPLAY createVirtualDisplay;
+        HWC2_PFN_DESTROY_LAYER destroyLayer;
+        HWC2_PFN_DESTROY_VIRTUAL_DISPLAY destroyVirtualDisplay;
+        HWC2_PFN_DUMP dump;
+        HWC2_PFN_GET_ACTIVE_CONFIG getActiveConfig;
+        HWC2_PFN_GET_CHANGED_COMPOSITION_TYPES getChangedCompositionTypes;
+        HWC2_PFN_GET_CLIENT_TARGET_SUPPORT getClientTargetSupport;
+        HWC2_PFN_GET_COLOR_MODES getColorModes;
+        HWC2_PFN_GET_DISPLAY_ATTRIBUTE getDisplayAttribute;
+        HWC2_PFN_GET_DISPLAY_CONFIGS getDisplayConfigs;
+        HWC2_PFN_GET_DISPLAY_NAME getDisplayName;
+        HWC2_PFN_GET_DISPLAY_REQUESTS getDisplayRequests;
+        HWC2_PFN_GET_DISPLAY_TYPE getDisplayType;
+        HWC2_PFN_GET_DOZE_SUPPORT getDozeSupport;
+        HWC2_PFN_GET_HDR_CAPABILITIES getHdrCapabilities;
+        HWC2_PFN_GET_MAX_VIRTUAL_DISPLAY_COUNT getMaxVirtualDisplayCount;
+        HWC2_PFN_GET_RELEASE_FENCES getReleaseFences;
+        HWC2_PFN_PRESENT_DISPLAY presentDisplay;
+        HWC2_PFN_REGISTER_CALLBACK registerCallback;
+        HWC2_PFN_SET_ACTIVE_CONFIG setActiveConfig;
+        HWC2_PFN_SET_CLIENT_TARGET setClientTarget;
+        HWC2_PFN_SET_COLOR_MODE setColorMode;
+        HWC2_PFN_SET_COLOR_TRANSFORM setColorTransform;
+        HWC2_PFN_SET_CURSOR_POSITION setCursorPosition;
+        HWC2_PFN_SET_LAYER_BLEND_MODE setLayerBlendMode;
+        HWC2_PFN_SET_LAYER_BUFFER setLayerBuffer;
+        HWC2_PFN_SET_LAYER_COLOR setLayerColor;
+        HWC2_PFN_SET_LAYER_COMPOSITION_TYPE setLayerCompositionType;
+        HWC2_PFN_SET_LAYER_DATASPACE setLayerDataspace;
+        HWC2_PFN_SET_LAYER_DISPLAY_FRAME setLayerDisplayFrame;
+        HWC2_PFN_SET_LAYER_PLANE_ALPHA setLayerPlaneAlpha;
+        HWC2_PFN_SET_LAYER_SIDEBAND_STREAM setLayerSidebandStream;
+        HWC2_PFN_SET_LAYER_SOURCE_CROP setLayerSourceCrop;
+        HWC2_PFN_SET_LAYER_SURFACE_DAMAGE setLayerSurfaceDamage;
+        HWC2_PFN_SET_LAYER_TRANSFORM setLayerTransform;
+        HWC2_PFN_SET_LAYER_VISIBLE_REGION setLayerVisibleRegion;
+        HWC2_PFN_SET_LAYER_Z_ORDER setLayerZOrder;
+        HWC2_PFN_SET_OUTPUT_BUFFER setOutputBuffer;
+        HWC2_PFN_SET_POWER_MODE setPowerMode;
+        HWC2_PFN_SET_VSYNC_ENABLED setVsyncEnabled;
+        HWC2_PFN_VALIDATE_DISPLAY validateDisplay;
+    } mDispatch = {};
+
+    hal::ComposerHal::EventCallback* mEventCallback = nullptr;
+
+    std::atomic<bool> mMustValidateDisplay{true};
+};
+
+}  // namespace detail
+
+using HwcHal = detail::HwcHalImpl<hal::ComposerHal>;
+
+}  // namespace passthrough
+}  // namespace V2_1
+}  // namespace composer
+}  // namespace graphics
+}  // namespace hardware
+}  // namespace android
diff --git a/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcLoader.h b/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcLoader.h
new file mode 100644
index 0000000..33c914d
--- /dev/null
+++ b/graphics/composer/2.1/utils/passthrough/include/composer-passthrough/2.1/HwcLoader.h
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#ifndef LOG_TAG
+#warning "HwcLoader.h included without LOG_TAG"
+#endif
+
+#include <memory>
+
+#include <composer-hal/2.1/Composer.h>
+#include <composer-passthrough/2.1/HwcHal.h>
+#include <hardware/fb.h>
+#include <hardware/gralloc.h>
+#include <hardware/hardware.h>
+#include <hardware/hwcomposer.h>
+#include <hardware/hwcomposer2.h>
+#include <hwc2on1adapter/HWC2On1Adapter.h>
+#include <hwc2onfbadapter/HWC2OnFbAdapter.h>
+#include <log/log.h>
+
+namespace android {
+namespace hardware {
+namespace graphics {
+namespace composer {
+namespace V2_1 {
+namespace passthrough {
+
+class HwcLoader {
+   public:
+    static IComposer* load() {
+        const hw_module_t* module = loadModule();
+        if (!module) {
+            return nullptr;
+        }
+
+        auto hal = createHalWithAdapter(module);
+        if (!hal) {
+            return nullptr;
+        }
+
+        return createComposer(std::move(hal));
+    }
+
+    // load hwcomposer2 module
+    static const hw_module_t* loadModule() {
+        const hw_module_t* module;
+        int error = hw_get_module(HWC_HARDWARE_MODULE_ID, &module);
+        if (error) {
+            ALOGI("falling back to gralloc module");
+            error = hw_get_module(GRALLOC_HARDWARE_MODULE_ID, &module);
+        }
+
+        if (error) {
+            ALOGE("failed to get hwcomposer or gralloc module");
+            return nullptr;
+        }
+
+        return module;
+    }
+
+    // create a ComposerHal instance
+    static std::unique_ptr<hal::ComposerHal> createHal(const hw_module_t* module) {
+        auto hal = std::make_unique<HwcHal>();
+        return hal->initWithModule(module) ? std::move(hal) : nullptr;
+    }
+
+    // create a ComposerHal instance, insert an adapter if necessary
+    static std::unique_ptr<hal::ComposerHal> createHalWithAdapter(const hw_module_t* module) {
+        bool adapted;
+        hwc2_device_t* device = openDeviceWithAdapter(module, &adapted);
+        if (!device) {
+            return nullptr;
+        }
+        auto hal = std::make_unique<HwcHal>();
+        return hal->initWithDevice(std::move(device), !adapted) ? std::move(hal) : nullptr;
+    }
+
+    // create an IComposer instance
+    static IComposer* createComposer(std::unique_ptr<hal::ComposerHal> hal) {
+        return hal::Composer::create(std::move(hal)).release();
+    }
+
+   protected:
+    // open hwcomposer2 device, install an adapter if necessary
+    static hwc2_device_t* openDeviceWithAdapter(const hw_module_t* module, bool* outAdapted) {
+        if (module->id && std::string(module->id) == GRALLOC_HARDWARE_MODULE_ID) {
+            *outAdapted = true;
+            return adaptGrallocModule(module);
+        }
+
+        hw_device_t* device;
+        int error = module->methods->open(module, HWC_HARDWARE_COMPOSER, &device);
+        if (error) {
+            ALOGE("failed to open hwcomposer device: %s", strerror(-error));
+            return nullptr;
+        }
+
+        int major = (device->version >> 24) & 0xf;
+        if (major != 2) {
+            *outAdapted = true;
+            return adaptHwc1Device(std::move(reinterpret_cast<hwc_composer_device_1*>(device)));
+        }
+
+        *outAdapted = false;
+        return reinterpret_cast<hwc2_device_t*>(device);
+    }
+
+   private:
+    static hwc2_device_t* adaptGrallocModule(const hw_module_t* module) {
+        framebuffer_device_t* device;
+        int error = framebuffer_open(module, &device);
+        if (error) {
+            ALOGE("failed to open framebuffer device: %s", strerror(-error));
+            return nullptr;
+        }
+
+        return new HWC2OnFbAdapter(device);
+    }
+
+    static hwc2_device_t* adaptHwc1Device(hwc_composer_device_1* device) {
+        int minor = (device->common.version >> 16) & 0xf;
+        if (minor < 1) {
+            ALOGE("hwcomposer 1.0 is not supported");
+            device->common.close(&device->common);
+            return nullptr;
+        }
+
+        return new HWC2On1Adapter(device);
+    }
+};
+
+}  // namespace passthrough
+}  // namespace V2_1
+}  // namespace composer
+}  // namespace graphics
+}  // namespace hardware
+}  // namespace android