diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/Android.bp b/graphics/composer/2.1/utils/hwc2on1adapter/Android.bp
new file mode 100644
index 0000000..420a1f6
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/Android.bp
@@ -0,0 +1,76 @@
+// Copyright 2010 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_library_shared {
+    name: "libhwc2on1adapter",
+    vendor: true,
+
+    clang: true,
+    cflags: [
+        "-Wall",
+        "-Werror",
+        "-Wno-user-defined-warnings",
+    ],
+    cppflags: [
+        "-Weverything",
+        "-Wunused",
+        "-Wunreachable-code",
+
+        // The static constructors and destructors in this library have not been noted to
+        // introduce significant overheads
+        "-Wno-exit-time-destructors",
+        "-Wno-global-constructors",
+
+        // We only care about compiling as C++14
+        "-Wno-c++98-compat-pedantic",
+
+        // android/sensors.h uses nested anonymous unions and anonymous structs
+        "-Wno-nested-anon-types",
+        "-Wno-gnu-anonymous-struct",
+
+        // Don't warn about struct padding
+        "-Wno-padded",
+
+        // hwcomposer2.h features switch covering all cases.
+        "-Wno-covered-switch-default",
+
+        // hwcomposer.h features zero size array.
+        "-Wno-zero-length-array",
+
+        // Disabling warning specific to hwc2on1adapter code
+        "-Wno-double-promotion",
+        "-Wno-sign-conversion",
+        "-Wno-switch-enum",
+        "-Wno-float-equal",
+        "-Wno-shorten-64-to-32",
+        "-Wno-sign-compare",
+        "-Wno-missing-prototypes",
+    ],
+
+    srcs: [
+        "HWC2On1Adapter.cpp",
+        "MiniFence.cpp",
+    ],
+
+    shared_libs: [
+        "libutils",
+        "libcutils",
+        "liblog",
+        "libhardware",
+    ],
+
+    export_include_dirs: ["include"],
+
+    export_shared_lib_headers: ["libutils"],
+}
diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/CleanSpec.mk b/graphics/composer/2.1/utils/hwc2on1adapter/CleanSpec.mk
new file mode 100644
index 0000000..7fc2216
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/CleanSpec.mk
@@ -0,0 +1,52 @@
+# Copyright (C) 2017 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.
+#
+
+# If you don't need to do a full clean build but would like to touch
+# a file or delete some intermediate files, add a clean step to the end
+# of the list.  These steps will only be run once, if they haven't been
+# run before.
+#
+# E.g.:
+#     $(call add-clean-step, touch -c external/sqlite/sqlite3.h)
+#     $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libz_intermediates)
+#
+# Always use "touch -c" and "rm -f" or "rm -rf" to gracefully deal with
+# files that are missing or have been moved.
+#
+# Use $(PRODUCT_OUT) to get to the "out/target/product/blah/" directory.
+# Use $(OUT_DIR) to refer to the "out" directory.
+#
+# If you need to re-do something that's already mentioned, just copy
+# the command and add it to the bottom of the list.  E.g., if a change
+# that you made last week required touching a file and a change you
+# made today requires touching the same file, just copy the old
+# touch step and add it to the end of the list.
+#
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
+
+# For example:
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/AndroidTests_intermediates)
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/core_intermediates)
+#$(call add-clean-step, find $(OUT_DIR) -type f -name "IGTalkSession*" -print0 | xargs -0 rm -f)
+#$(call add-clean-step, rm -rf $(PRODUCT_OUT)/data/*)
+
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libhwc2on1adapter_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/lib/libhwc2on1adapter.so)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/lib64/libhwc2on1adapter.so)
diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/HWC2On1Adapter.cpp b/graphics/composer/2.1/utils/hwc2on1adapter/HWC2On1Adapter.cpp
new file mode 100644
index 0000000..77f06bb
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/HWC2On1Adapter.cpp
@@ -0,0 +1,2637 @@
+/*
+ * Copyright 2015 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 "hwc2on1adapter/HWC2On1Adapter.h"
+
+//#define LOG_NDEBUG 0
+
+#undef LOG_TAG
+#define LOG_TAG "HWC2On1Adapter"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+
+
+#include <inttypes.h>
+
+#include <chrono>
+#include <cstdlib>
+#include <sstream>
+
+#include <hardware/hwcomposer.h>
+#include <log/log.h>
+#include <utils/Trace.h>
+
+using namespace std::chrono_literals;
+
+static uint8_t getMinorVersion(struct hwc_composer_device_1* device)
+{
+    auto version = device->common.version & HARDWARE_API_VERSION_2_MAJ_MIN_MASK;
+    return (version >> 16) & 0xF;
+}
+
+template <typename PFN, typename T>
+static hwc2_function_pointer_t asFP(T function)
+{
+    static_assert(std::is_same<PFN, T>::value, "Incompatible function pointer");
+    return reinterpret_cast<hwc2_function_pointer_t>(function);
+}
+
+using namespace HWC2;
+
+static constexpr Attribute ColorMode = static_cast<Attribute>(6);
+
+namespace android {
+
+class HWC2On1Adapter::Callbacks : public hwc_procs_t {
+    public:
+        explicit Callbacks(HWC2On1Adapter& adapter) : mAdapter(adapter) {
+            invalidate = &invalidateHook;
+            vsync = &vsyncHook;
+            hotplug = &hotplugHook;
+        }
+
+        static void invalidateHook(const hwc_procs_t* procs) {
+            auto callbacks = static_cast<const Callbacks*>(procs);
+            callbacks->mAdapter.hwc1Invalidate();
+        }
+
+        static void vsyncHook(const hwc_procs_t* procs, int display,
+                int64_t timestamp) {
+            auto callbacks = static_cast<const Callbacks*>(procs);
+            callbacks->mAdapter.hwc1Vsync(display, timestamp);
+        }
+
+        static void hotplugHook(const hwc_procs_t* procs, int display,
+                int connected) {
+            auto callbacks = static_cast<const Callbacks*>(procs);
+            callbacks->mAdapter.hwc1Hotplug(display, connected);
+        }
+
+    private:
+        HWC2On1Adapter& mAdapter;
+};
+
+static int closeHook(hw_device_t* /*device*/)
+{
+    // Do nothing, since the real work is done in the class destructor, but we
+    // need to provide a valid function pointer for hwc2_close to call
+    return 0;
+}
+
+HWC2On1Adapter::HWC2On1Adapter(hwc_composer_device_1_t* hwc1Device)
+  : mDumpString(),
+    mHwc1Device(hwc1Device),
+    mHwc1MinorVersion(getMinorVersion(hwc1Device)),
+    mHwc1SupportsVirtualDisplays(false),
+    mHwc1SupportsBackgroundColor(false),
+    mHwc1Callbacks(std::make_unique<Callbacks>(*this)),
+    mCapabilities(),
+    mLayers(),
+    mHwc1VirtualDisplay(),
+    mStateMutex(),
+    mCallbacks(),
+    mHasPendingInvalidate(false),
+    mPendingVsyncs(),
+    mPendingHotplugs(),
+    mDisplays(),
+    mHwc1DisplayMap()
+{
+    common.close = closeHook;
+    getCapabilities = getCapabilitiesHook;
+    getFunction = getFunctionHook;
+    populateCapabilities();
+    populatePrimary();
+    mHwc1Device->registerProcs(mHwc1Device,
+            static_cast<const hwc_procs_t*>(mHwc1Callbacks.get()));
+}
+
+HWC2On1Adapter::~HWC2On1Adapter() {
+    hwc_close_1(mHwc1Device);
+}
+
+void HWC2On1Adapter::doGetCapabilities(uint32_t* outCount,
+        int32_t* outCapabilities) {
+    if (outCapabilities == nullptr) {
+        *outCount = mCapabilities.size();
+        return;
+    }
+
+    auto capabilityIter = mCapabilities.cbegin();
+    for (size_t written = 0; written < *outCount; ++written) {
+        if (capabilityIter == mCapabilities.cend()) {
+            return;
+        }
+        outCapabilities[written] = static_cast<int32_t>(*capabilityIter);
+        ++capabilityIter;
+    }
+}
+
+hwc2_function_pointer_t HWC2On1Adapter::doGetFunction(
+        FunctionDescriptor descriptor) {
+    switch (descriptor) {
+        // Device functions
+        case FunctionDescriptor::CreateVirtualDisplay:
+            return asFP<HWC2_PFN_CREATE_VIRTUAL_DISPLAY>(
+                    createVirtualDisplayHook);
+        case FunctionDescriptor::DestroyVirtualDisplay:
+            return asFP<HWC2_PFN_DESTROY_VIRTUAL_DISPLAY>(
+                    destroyVirtualDisplayHook);
+        case FunctionDescriptor::Dump:
+            return asFP<HWC2_PFN_DUMP>(dumpHook);
+        case FunctionDescriptor::GetMaxVirtualDisplayCount:
+            return asFP<HWC2_PFN_GET_MAX_VIRTUAL_DISPLAY_COUNT>(
+                    getMaxVirtualDisplayCountHook);
+        case FunctionDescriptor::RegisterCallback:
+            return asFP<HWC2_PFN_REGISTER_CALLBACK>(registerCallbackHook);
+
+        // Display functions
+        case FunctionDescriptor::AcceptDisplayChanges:
+            return asFP<HWC2_PFN_ACCEPT_DISPLAY_CHANGES>(
+                    displayHook<decltype(&Display::acceptChanges),
+                    &Display::acceptChanges>);
+        case FunctionDescriptor::CreateLayer:
+            return asFP<HWC2_PFN_CREATE_LAYER>(
+                    displayHook<decltype(&Display::createLayer),
+                    &Display::createLayer, hwc2_layer_t*>);
+        case FunctionDescriptor::DestroyLayer:
+            return asFP<HWC2_PFN_DESTROY_LAYER>(
+                    displayHook<decltype(&Display::destroyLayer),
+                    &Display::destroyLayer, hwc2_layer_t>);
+        case FunctionDescriptor::GetActiveConfig:
+            return asFP<HWC2_PFN_GET_ACTIVE_CONFIG>(
+                    displayHook<decltype(&Display::getActiveConfig),
+                    &Display::getActiveConfig, hwc2_config_t*>);
+        case FunctionDescriptor::GetChangedCompositionTypes:
+            return asFP<HWC2_PFN_GET_CHANGED_COMPOSITION_TYPES>(
+                    displayHook<decltype(&Display::getChangedCompositionTypes),
+                    &Display::getChangedCompositionTypes, uint32_t*,
+                    hwc2_layer_t*, int32_t*>);
+        case FunctionDescriptor::GetColorModes:
+            return asFP<HWC2_PFN_GET_COLOR_MODES>(
+                    displayHook<decltype(&Display::getColorModes),
+                    &Display::getColorModes, uint32_t*, int32_t*>);
+        case FunctionDescriptor::GetDisplayAttribute:
+            return asFP<HWC2_PFN_GET_DISPLAY_ATTRIBUTE>(
+                    getDisplayAttributeHook);
+        case FunctionDescriptor::GetDisplayConfigs:
+            return asFP<HWC2_PFN_GET_DISPLAY_CONFIGS>(
+                    displayHook<decltype(&Display::getConfigs),
+                    &Display::getConfigs, uint32_t*, hwc2_config_t*>);
+        case FunctionDescriptor::GetDisplayName:
+            return asFP<HWC2_PFN_GET_DISPLAY_NAME>(
+                    displayHook<decltype(&Display::getName),
+                    &Display::getName, uint32_t*, char*>);
+        case FunctionDescriptor::GetDisplayRequests:
+            return asFP<HWC2_PFN_GET_DISPLAY_REQUESTS>(
+                    displayHook<decltype(&Display::getRequests),
+                    &Display::getRequests, int32_t*, uint32_t*, hwc2_layer_t*,
+                    int32_t*>);
+        case FunctionDescriptor::GetDisplayType:
+            return asFP<HWC2_PFN_GET_DISPLAY_TYPE>(
+                    displayHook<decltype(&Display::getType),
+                    &Display::getType, int32_t*>);
+        case FunctionDescriptor::GetDozeSupport:
+            return asFP<HWC2_PFN_GET_DOZE_SUPPORT>(
+                    displayHook<decltype(&Display::getDozeSupport),
+                    &Display::getDozeSupport, int32_t*>);
+        case FunctionDescriptor::GetHdrCapabilities:
+            return asFP<HWC2_PFN_GET_HDR_CAPABILITIES>(
+                    displayHook<decltype(&Display::getHdrCapabilities),
+                    &Display::getHdrCapabilities, uint32_t*, int32_t*, float*,
+                    float*, float*>);
+        case FunctionDescriptor::GetReleaseFences:
+            return asFP<HWC2_PFN_GET_RELEASE_FENCES>(
+                    displayHook<decltype(&Display::getReleaseFences),
+                    &Display::getReleaseFences, uint32_t*, hwc2_layer_t*,
+                    int32_t*>);
+        case FunctionDescriptor::PresentDisplay:
+            return asFP<HWC2_PFN_PRESENT_DISPLAY>(
+                    displayHook<decltype(&Display::present),
+                    &Display::present, int32_t*>);
+        case FunctionDescriptor::SetActiveConfig:
+            return asFP<HWC2_PFN_SET_ACTIVE_CONFIG>(
+                    displayHook<decltype(&Display::setActiveConfig),
+                    &Display::setActiveConfig, hwc2_config_t>);
+        case FunctionDescriptor::SetClientTarget:
+            return asFP<HWC2_PFN_SET_CLIENT_TARGET>(
+                    displayHook<decltype(&Display::setClientTarget),
+                    &Display::setClientTarget, buffer_handle_t, int32_t,
+                    int32_t, hwc_region_t>);
+        case FunctionDescriptor::SetColorMode:
+            return asFP<HWC2_PFN_SET_COLOR_MODE>(setColorModeHook);
+        case FunctionDescriptor::SetColorTransform:
+            return asFP<HWC2_PFN_SET_COLOR_TRANSFORM>(setColorTransformHook);
+        case FunctionDescriptor::SetOutputBuffer:
+            return asFP<HWC2_PFN_SET_OUTPUT_BUFFER>(
+                    displayHook<decltype(&Display::setOutputBuffer),
+                    &Display::setOutputBuffer, buffer_handle_t, int32_t>);
+        case FunctionDescriptor::SetPowerMode:
+            return asFP<HWC2_PFN_SET_POWER_MODE>(setPowerModeHook);
+        case FunctionDescriptor::SetVsyncEnabled:
+            return asFP<HWC2_PFN_SET_VSYNC_ENABLED>(setVsyncEnabledHook);
+        case FunctionDescriptor::ValidateDisplay:
+            return asFP<HWC2_PFN_VALIDATE_DISPLAY>(
+                    displayHook<decltype(&Display::validate),
+                    &Display::validate, uint32_t*, uint32_t*>);
+        case FunctionDescriptor::GetClientTargetSupport:
+            return asFP<HWC2_PFN_GET_CLIENT_TARGET_SUPPORT>(
+                    displayHook<decltype(&Display::getClientTargetSupport),
+                    &Display::getClientTargetSupport, uint32_t, uint32_t,
+                                                      int32_t, int32_t>);
+
+        // Layer functions
+        case FunctionDescriptor::SetCursorPosition:
+            return asFP<HWC2_PFN_SET_CURSOR_POSITION>(
+                    layerHook<decltype(&Layer::setCursorPosition),
+                    &Layer::setCursorPosition, int32_t, int32_t>);
+        case FunctionDescriptor::SetLayerBuffer:
+            return asFP<HWC2_PFN_SET_LAYER_BUFFER>(
+                    layerHook<decltype(&Layer::setBuffer), &Layer::setBuffer,
+                    buffer_handle_t, int32_t>);
+        case FunctionDescriptor::SetLayerSurfaceDamage:
+            return asFP<HWC2_PFN_SET_LAYER_SURFACE_DAMAGE>(
+                    layerHook<decltype(&Layer::setSurfaceDamage),
+                    &Layer::setSurfaceDamage, hwc_region_t>);
+
+        // Layer state functions
+        case FunctionDescriptor::SetLayerBlendMode:
+            return asFP<HWC2_PFN_SET_LAYER_BLEND_MODE>(
+                    setLayerBlendModeHook);
+        case FunctionDescriptor::SetLayerColor:
+            return asFP<HWC2_PFN_SET_LAYER_COLOR>(
+                    layerHook<decltype(&Layer::setColor), &Layer::setColor,
+                    hwc_color_t>);
+        case FunctionDescriptor::SetLayerCompositionType:
+            return asFP<HWC2_PFN_SET_LAYER_COMPOSITION_TYPE>(
+                    setLayerCompositionTypeHook);
+        case FunctionDescriptor::SetLayerDataspace:
+            return asFP<HWC2_PFN_SET_LAYER_DATASPACE>(setLayerDataspaceHook);
+        case FunctionDescriptor::SetLayerDisplayFrame:
+            return asFP<HWC2_PFN_SET_LAYER_DISPLAY_FRAME>(
+                    layerHook<decltype(&Layer::setDisplayFrame),
+                    &Layer::setDisplayFrame, hwc_rect_t>);
+        case FunctionDescriptor::SetLayerPlaneAlpha:
+            return asFP<HWC2_PFN_SET_LAYER_PLANE_ALPHA>(
+                    layerHook<decltype(&Layer::setPlaneAlpha),
+                    &Layer::setPlaneAlpha, float>);
+        case FunctionDescriptor::SetLayerSidebandStream:
+            return asFP<HWC2_PFN_SET_LAYER_SIDEBAND_STREAM>(
+                    layerHook<decltype(&Layer::setSidebandStream),
+                    &Layer::setSidebandStream, const native_handle_t*>);
+        case FunctionDescriptor::SetLayerSourceCrop:
+            return asFP<HWC2_PFN_SET_LAYER_SOURCE_CROP>(
+                    layerHook<decltype(&Layer::setSourceCrop),
+                    &Layer::setSourceCrop, hwc_frect_t>);
+        case FunctionDescriptor::SetLayerTransform:
+            return asFP<HWC2_PFN_SET_LAYER_TRANSFORM>(setLayerTransformHook);
+        case FunctionDescriptor::SetLayerVisibleRegion:
+            return asFP<HWC2_PFN_SET_LAYER_VISIBLE_REGION>(
+                    layerHook<decltype(&Layer::setVisibleRegion),
+                    &Layer::setVisibleRegion, hwc_region_t>);
+        case FunctionDescriptor::SetLayerZOrder:
+            return asFP<HWC2_PFN_SET_LAYER_Z_ORDER>(setLayerZOrderHook);
+
+        default:
+            ALOGE("doGetFunction: Unknown function descriptor: %d (%s)",
+                    static_cast<int32_t>(descriptor),
+                    to_string(descriptor).c_str());
+            return nullptr;
+    }
+}
+
+// Device functions
+
+Error HWC2On1Adapter::createVirtualDisplay(uint32_t width,
+        uint32_t height, hwc2_display_t* outDisplay) {
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    if (mHwc1VirtualDisplay) {
+        // We have already allocated our only HWC1 virtual display
+        ALOGE("createVirtualDisplay: HWC1 virtual display already allocated");
+        return Error::NoResources;
+    }
+
+    mHwc1VirtualDisplay = std::make_shared<HWC2On1Adapter::Display>(*this,
+            HWC2::DisplayType::Virtual);
+    mHwc1VirtualDisplay->populateConfigs(width, height);
+    const auto displayId = mHwc1VirtualDisplay->getId();
+    mHwc1DisplayMap[HWC_DISPLAY_VIRTUAL] = displayId;
+    mHwc1VirtualDisplay->setHwc1Id(HWC_DISPLAY_VIRTUAL);
+    mDisplays.emplace(displayId, mHwc1VirtualDisplay);
+    *outDisplay = displayId;
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::destroyVirtualDisplay(hwc2_display_t displayId) {
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    if (!mHwc1VirtualDisplay || (mHwc1VirtualDisplay->getId() != displayId)) {
+        return Error::BadDisplay;
+    }
+
+    mHwc1VirtualDisplay.reset();
+    mHwc1DisplayMap.erase(HWC_DISPLAY_VIRTUAL);
+    mDisplays.erase(displayId);
+
+    return Error::None;
+}
+
+void HWC2On1Adapter::dump(uint32_t* outSize, char* outBuffer) {
+    if (outBuffer != nullptr) {
+        auto copiedBytes = mDumpString.copy(outBuffer, *outSize);
+        *outSize = static_cast<uint32_t>(copiedBytes);
+        return;
+    }
+
+    std::stringstream output;
+
+    output << "-- HWC2On1Adapter --\n";
+
+    output << "Adapting to a HWC 1." << static_cast<int>(mHwc1MinorVersion) <<
+            " device\n";
+
+    // Attempt to acquire the lock for 1 second, but proceed without the lock
+    // after that, so we can still get some information if we're deadlocked
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex,
+            std::defer_lock);
+    lock.try_lock_for(1s);
+
+    if (mCapabilities.empty()) {
+        output << "Capabilities: None\n";
+    } else {
+        output << "Capabilities:\n";
+        for (auto capability : mCapabilities) {
+            output << "  " << to_string(capability) << '\n';
+        }
+    }
+
+    output << "Displays:\n";
+    for (const auto& element : mDisplays) {
+        const auto& display = element.second;
+        output << display->dump();
+    }
+    output << '\n';
+
+    // Release the lock before calling into HWC1, and since we no longer require
+    // mutual exclusion to access mCapabilities or mDisplays
+    lock.unlock();
+
+    if (mHwc1Device->dump) {
+        output << "HWC1 dump:\n";
+        std::vector<char> hwc1Dump(4096);
+        // Call with size - 1 to preserve a null character at the end
+        mHwc1Device->dump(mHwc1Device, hwc1Dump.data(),
+                static_cast<int>(hwc1Dump.size() - 1));
+        output << hwc1Dump.data();
+    }
+
+    mDumpString = output.str();
+    *outSize = static_cast<uint32_t>(mDumpString.size());
+}
+
+uint32_t HWC2On1Adapter::getMaxVirtualDisplayCount() {
+    return mHwc1SupportsVirtualDisplays ? 1 : 0;
+}
+
+static bool isValid(Callback descriptor) {
+    switch (descriptor) {
+        case Callback::Hotplug: // Fall-through
+        case Callback::Refresh: // Fall-through
+        case Callback::Vsync: return true;
+        default: return false;
+    }
+}
+
+Error HWC2On1Adapter::registerCallback(Callback descriptor,
+        hwc2_callback_data_t callbackData, hwc2_function_pointer_t pointer) {
+    if (!isValid(descriptor)) {
+        return Error::BadParameter;
+    }
+
+    ALOGV("registerCallback(%s, %p, %p)", to_string(descriptor).c_str(),
+            callbackData, pointer);
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    if (pointer != nullptr) {
+        mCallbacks[descriptor] = {callbackData, pointer};
+    } else {
+        ALOGI("unregisterCallback(%s)", to_string(descriptor).c_str());
+        mCallbacks.erase(descriptor);
+        return Error::None;
+    }
+
+    bool hasPendingInvalidate = false;
+    std::vector<hwc2_display_t> displayIds;
+    std::vector<std::pair<hwc2_display_t, int64_t>> pendingVsyncs;
+    std::vector<std::pair<hwc2_display_t, int>> pendingHotplugs;
+
+    if (descriptor == Callback::Refresh) {
+        hasPendingInvalidate = mHasPendingInvalidate;
+        if (hasPendingInvalidate) {
+            for (auto& displayPair : mDisplays) {
+                displayIds.emplace_back(displayPair.first);
+            }
+        }
+        mHasPendingInvalidate = false;
+    } else if (descriptor == Callback::Vsync) {
+        for (auto pending : mPendingVsyncs) {
+            auto hwc1DisplayId = pending.first;
+            if (mHwc1DisplayMap.count(hwc1DisplayId) == 0) {
+                ALOGE("hwc1Vsync: Couldn't find display for HWC1 id %d",
+                        hwc1DisplayId);
+                continue;
+            }
+            auto displayId = mHwc1DisplayMap[hwc1DisplayId];
+            auto timestamp = pending.second;
+            pendingVsyncs.emplace_back(displayId, timestamp);
+        }
+        mPendingVsyncs.clear();
+    } else if (descriptor == Callback::Hotplug) {
+        // Hotplug the primary display
+        pendingHotplugs.emplace_back(mHwc1DisplayMap[HWC_DISPLAY_PRIMARY],
+                static_cast<int32_t>(Connection::Connected));
+
+        for (auto pending : mPendingHotplugs) {
+            auto hwc1DisplayId = pending.first;
+            if (mHwc1DisplayMap.count(hwc1DisplayId) == 0) {
+                ALOGE("hwc1Hotplug: Couldn't find display for HWC1 id %d",
+                        hwc1DisplayId);
+                continue;
+            }
+            auto displayId = mHwc1DisplayMap[hwc1DisplayId];
+            auto connected = pending.second;
+            pendingHotplugs.emplace_back(displayId, connected);
+        }
+    }
+
+    // Call pending callbacks without the state lock held
+    lock.unlock();
+
+    if (hasPendingInvalidate) {
+        auto refresh = reinterpret_cast<HWC2_PFN_REFRESH>(pointer);
+        for (auto displayId : displayIds) {
+            refresh(callbackData, displayId);
+        }
+    }
+    if (!pendingVsyncs.empty()) {
+        auto vsync = reinterpret_cast<HWC2_PFN_VSYNC>(pointer);
+        for (auto& pendingVsync : pendingVsyncs) {
+            vsync(callbackData, pendingVsync.first, pendingVsync.second);
+        }
+    }
+    if (!pendingHotplugs.empty()) {
+        auto hotplug = reinterpret_cast<HWC2_PFN_HOTPLUG>(pointer);
+        for (auto& pendingHotplug : pendingHotplugs) {
+            hotplug(callbackData, pendingHotplug.first, pendingHotplug.second);
+        }
+    }
+    return Error::None;
+}
+
+// Display functions
+
+std::atomic<hwc2_display_t> HWC2On1Adapter::Display::sNextId(1);
+
+HWC2On1Adapter::Display::Display(HWC2On1Adapter& device, HWC2::DisplayType type)
+  : mId(sNextId++),
+    mDevice(device),
+    mStateMutex(),
+    mHwc1RequestedContents(nullptr),
+    mRetireFence(),
+    mChanges(),
+    mHwc1Id(-1),
+    mConfigs(),
+    mActiveConfig(nullptr),
+    mActiveColorMode(static_cast<android_color_mode_t>(-1)),
+    mName(),
+    mType(type),
+    mPowerMode(PowerMode::Off),
+    mVsyncEnabled(Vsync::Invalid),
+    mClientTarget(),
+    mOutputBuffer(),
+    mHasColorTransform(false),
+    mLayers(),
+    mHwc1LayerMap(),
+    mNumAvailableRects(0),
+    mNextAvailableRect(nullptr),
+    mGeometryChanged(false)
+    {}
+
+Error HWC2On1Adapter::Display::acceptChanges() {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mChanges) {
+        ALOGV("[%" PRIu64 "] acceptChanges failed, not validated", mId);
+        return Error::NotValidated;
+    }
+
+    ALOGV("[%" PRIu64 "] acceptChanges", mId);
+
+    for (auto& change : mChanges->getTypeChanges()) {
+        auto layerId = change.first;
+        auto type = change.second;
+        if (mDevice.mLayers.count(layerId) == 0) {
+            // This should never happen but somehow does.
+            ALOGW("Cannot accept change for unknown layer (%" PRIu64 ")",
+                  layerId);
+            continue;
+        }
+        auto layer = mDevice.mLayers[layerId];
+        layer->setCompositionType(type);
+    }
+
+    mChanges->clearTypeChanges();
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::createLayer(hwc2_layer_t* outLayerId) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    auto layer = *mLayers.emplace(std::make_shared<Layer>(*this));
+    mDevice.mLayers.emplace(std::make_pair(layer->getId(), layer));
+    *outLayerId = layer->getId();
+    ALOGV("[%" PRIu64 "] created layer %" PRIu64, mId, *outLayerId);
+    markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::destroyLayer(hwc2_layer_t layerId) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    const auto mapLayer = mDevice.mLayers.find(layerId);
+    if (mapLayer == mDevice.mLayers.end()) {
+        ALOGV("[%" PRIu64 "] destroyLayer(%" PRIu64 ") failed: no such layer",
+                mId, layerId);
+        return Error::BadLayer;
+    }
+    const auto layer = mapLayer->second;
+    mDevice.mLayers.erase(mapLayer);
+    const auto zRange = mLayers.equal_range(layer);
+    for (auto current = zRange.first; current != zRange.second; ++current) {
+        if (**current == *layer) {
+            current = mLayers.erase(current);
+            break;
+        }
+    }
+    ALOGV("[%" PRIu64 "] destroyed layer %" PRIu64, mId, layerId);
+    markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getActiveConfig(hwc2_config_t* outConfig) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mActiveConfig) {
+        ALOGV("[%" PRIu64 "] getActiveConfig --> %s", mId,
+                to_string(Error::BadConfig).c_str());
+        return Error::BadConfig;
+    }
+    auto configId = mActiveConfig->getId();
+    ALOGV("[%" PRIu64 "] getActiveConfig --> %u", mId, configId);
+    *outConfig = configId;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getAttribute(hwc2_config_t configId,
+        Attribute attribute, int32_t* outValue) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (configId > mConfigs.size() || !mConfigs[configId]->isOnDisplay(*this)) {
+        ALOGV("[%" PRIu64 "] getAttribute failed: bad config (%u)", mId,
+                configId);
+        return Error::BadConfig;
+    }
+    *outValue = mConfigs[configId]->getAttribute(attribute);
+    ALOGV("[%" PRIu64 "] getAttribute(%u, %s) --> %d", mId, configId,
+            to_string(attribute).c_str(), *outValue);
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getChangedCompositionTypes(
+        uint32_t* outNumElements, hwc2_layer_t* outLayers, int32_t* outTypes) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mChanges) {
+        ALOGE("[%" PRIu64 "] getChangedCompositionTypes failed: not validated",
+                mId);
+        return Error::NotValidated;
+    }
+
+    if ((outLayers == nullptr) || (outTypes == nullptr)) {
+        *outNumElements = mChanges->getTypeChanges().size();
+        return Error::None;
+    }
+
+    uint32_t numWritten = 0;
+    for (const auto& element : mChanges->getTypeChanges()) {
+        if (numWritten == *outNumElements) {
+            break;
+        }
+        auto layerId = element.first;
+        auto intType = static_cast<int32_t>(element.second);
+        ALOGV("Adding %" PRIu64 " %s", layerId,
+                to_string(element.second).c_str());
+        outLayers[numWritten] = layerId;
+        outTypes[numWritten] = intType;
+        ++numWritten;
+    }
+    *outNumElements = numWritten;
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getColorModes(uint32_t* outNumModes,
+        int32_t* outModes) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!outModes) {
+        *outNumModes = mColorModes.size();
+        return Error::None;
+    }
+    uint32_t numModes = std::min(*outNumModes,
+            static_cast<uint32_t>(mColorModes.size()));
+    std::copy_n(mColorModes.cbegin(), numModes, outModes);
+    *outNumModes = numModes;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getConfigs(uint32_t* outNumConfigs,
+        hwc2_config_t* outConfigs) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!outConfigs) {
+        *outNumConfigs = mConfigs.size();
+        return Error::None;
+    }
+    uint32_t numWritten = 0;
+    for (const auto& config : mConfigs) {
+        if (numWritten == *outNumConfigs) {
+            break;
+        }
+        outConfigs[numWritten] = config->getId();
+        ++numWritten;
+    }
+    *outNumConfigs = numWritten;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getDozeSupport(int32_t* outSupport) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (mDevice.mHwc1MinorVersion < 4 || mHwc1Id != 0) {
+        *outSupport = 0;
+    } else {
+        *outSupport = 1;
+    }
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getHdrCapabilities(uint32_t* outNumTypes,
+        int32_t* /*outTypes*/, float* /*outMaxLuminance*/,
+        float* /*outMaxAverageLuminance*/, float* /*outMinLuminance*/) {
+    // This isn't supported on HWC1, so per the HWC2 header, return numTypes = 0
+    *outNumTypes = 0;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getName(uint32_t* outSize, char* outName) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!outName) {
+        *outSize = mName.size();
+        return Error::None;
+    }
+    auto numCopied = mName.copy(outName, *outSize);
+    *outSize = numCopied;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getReleaseFences(uint32_t* outNumElements,
+        hwc2_layer_t* outLayers, int32_t* outFences) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    uint32_t numWritten = 0;
+    bool outputsNonNull = (outLayers != nullptr) && (outFences != nullptr);
+    for (const auto& layer : mLayers) {
+        if (outputsNonNull && (numWritten == *outNumElements)) {
+            break;
+        }
+
+        auto releaseFence = layer->getReleaseFence();
+        if (releaseFence != MiniFence::NO_FENCE) {
+            if (outputsNonNull) {
+                outLayers[numWritten] = layer->getId();
+                outFences[numWritten] = releaseFence->dup();
+            }
+            ++numWritten;
+        }
+    }
+    *outNumElements = numWritten;
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getRequests(int32_t* outDisplayRequests,
+        uint32_t* outNumElements, hwc2_layer_t* outLayers,
+        int32_t* outLayerRequests) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mChanges) {
+        return Error::NotValidated;
+    }
+
+    if (outLayers == nullptr || outLayerRequests == nullptr) {
+        *outNumElements = mChanges->getNumLayerRequests();
+        return Error::None;
+    }
+
+    // Display requests (HWC2::DisplayRequest) are not supported by hwc1:
+    // A hwc1 has always zero requests for the client.
+    *outDisplayRequests = 0;
+
+    uint32_t numWritten = 0;
+    for (const auto& request : mChanges->getLayerRequests()) {
+        if (numWritten == *outNumElements) {
+            break;
+        }
+        outLayers[numWritten] = request.first;
+        outLayerRequests[numWritten] = static_cast<int32_t>(request.second);
+        ++numWritten;
+    }
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getType(int32_t* outType) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    *outType = static_cast<int32_t>(mType);
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::present(int32_t* outRetireFence) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (mChanges) {
+        Error error = mDevice.setAllDisplays();
+        if (error != Error::None) {
+            ALOGE("[%" PRIu64 "] present: setAllDisplaysFailed (%s)", mId,
+                    to_string(error).c_str());
+            return error;
+        }
+    }
+
+    *outRetireFence = mRetireFence.get()->dup();
+    ALOGV("[%" PRIu64 "] present returning retire fence %d", mId,
+            *outRetireFence);
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::setActiveConfig(hwc2_config_t configId) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    auto config = getConfig(configId);
+    if (!config) {
+        return Error::BadConfig;
+    }
+    if (config == mActiveConfig) {
+        return Error::None;
+    }
+
+    if (mDevice.mHwc1MinorVersion >= 4) {
+        uint32_t hwc1Id = 0;
+        auto error = config->getHwc1IdForColorMode(mActiveColorMode, &hwc1Id);
+        if (error != Error::None) {
+            return error;
+        }
+
+        int intError = mDevice.mHwc1Device->setActiveConfig(mDevice.mHwc1Device,
+                mHwc1Id, static_cast<int>(hwc1Id));
+        if (intError != 0) {
+            ALOGE("setActiveConfig: Failed to set active config on HWC1 (%d)",
+                intError);
+            return Error::BadConfig;
+        }
+        mActiveConfig = config;
+    }
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::setClientTarget(buffer_handle_t target,
+        int32_t acquireFence, int32_t /*dataspace*/, hwc_region_t /*damage*/) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    ALOGV("[%" PRIu64 "] setClientTarget(%p, %d)", mId, target, acquireFence);
+    mClientTarget.setBuffer(target);
+    mClientTarget.setFence(acquireFence);
+    // dataspace and damage can't be used by HWC1, so ignore them
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::setColorMode(android_color_mode_t mode) {
+    std::unique_lock<std::recursive_mutex> lock (mStateMutex);
+
+    ALOGV("[%" PRIu64 "] setColorMode(%d)", mId, mode);
+
+    if (mode == mActiveColorMode) {
+        return Error::None;
+    }
+    if (mColorModes.count(mode) == 0) {
+        ALOGE("[%" PRIu64 "] Mode %d not found in mColorModes", mId, mode);
+        return Error::Unsupported;
+    }
+
+    uint32_t hwc1Config = 0;
+    auto error = mActiveConfig->getHwc1IdForColorMode(mode, &hwc1Config);
+    if (error != Error::None) {
+        return error;
+    }
+
+    ALOGV("[%" PRIu64 "] Setting HWC1 config %u", mId, hwc1Config);
+    int intError = mDevice.mHwc1Device->setActiveConfig(mDevice.mHwc1Device,
+            mHwc1Id, hwc1Config);
+    if (intError != 0) {
+        ALOGE("[%" PRIu64 "] Failed to set HWC1 config (%d)", mId, intError);
+        return Error::Unsupported;
+    }
+
+    mActiveColorMode = mode;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::setColorTransform(android_color_transform_t hint) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    ALOGV("%" PRIu64 "] setColorTransform(%d)", mId,
+            static_cast<int32_t>(hint));
+    mHasColorTransform = (hint != HAL_COLOR_TRANSFORM_IDENTITY);
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::setOutputBuffer(buffer_handle_t buffer,
+        int32_t releaseFence) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    ALOGV("[%" PRIu64 "] setOutputBuffer(%p, %d)", mId, buffer, releaseFence);
+    mOutputBuffer.setBuffer(buffer);
+    mOutputBuffer.setFence(releaseFence);
+    return Error::None;
+}
+
+static bool isValid(PowerMode mode) {
+    switch (mode) {
+        case PowerMode::Off: // Fall-through
+        case PowerMode::DozeSuspend: // Fall-through
+        case PowerMode::Doze: // Fall-through
+        case PowerMode::On: return true;
+    }
+}
+
+static int getHwc1PowerMode(PowerMode mode) {
+    switch (mode) {
+        case PowerMode::Off: return HWC_POWER_MODE_OFF;
+        case PowerMode::DozeSuspend: return HWC_POWER_MODE_DOZE_SUSPEND;
+        case PowerMode::Doze: return HWC_POWER_MODE_DOZE;
+        case PowerMode::On: return HWC_POWER_MODE_NORMAL;
+    }
+}
+
+Error HWC2On1Adapter::Display::setPowerMode(PowerMode mode) {
+    if (!isValid(mode)) {
+        return Error::BadParameter;
+    }
+    if (mode == mPowerMode) {
+        return Error::None;
+    }
+
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    int error = 0;
+    if (mDevice.mHwc1MinorVersion < 4) {
+        error = mDevice.mHwc1Device->blank(mDevice.mHwc1Device, mHwc1Id,
+                mode == PowerMode::Off);
+    } else {
+        error = mDevice.mHwc1Device->setPowerMode(mDevice.mHwc1Device,
+                mHwc1Id, getHwc1PowerMode(mode));
+    }
+    ALOGE_IF(error != 0, "setPowerMode: Failed to set power mode on HWC1 (%d)",
+            error);
+
+    ALOGV("[%" PRIu64 "] setPowerMode(%s)", mId, to_string(mode).c_str());
+    mPowerMode = mode;
+    return Error::None;
+}
+
+static bool isValid(Vsync enable) {
+    switch (enable) {
+        case Vsync::Enable: // Fall-through
+        case Vsync::Disable: return true;
+        case Vsync::Invalid: return false;
+    }
+}
+
+Error HWC2On1Adapter::Display::setVsyncEnabled(Vsync enable) {
+    if (!isValid(enable)) {
+        return Error::BadParameter;
+    }
+    if (enable == mVsyncEnabled) {
+        return Error::None;
+    }
+
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    int error = mDevice.mHwc1Device->eventControl(mDevice.mHwc1Device,
+            mHwc1Id, HWC_EVENT_VSYNC, enable == Vsync::Enable);
+    ALOGE_IF(error != 0, "setVsyncEnabled: Failed to set vsync on HWC1 (%d)",
+            error);
+
+    mVsyncEnabled = enable;
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::validate(uint32_t* outNumTypes,
+        uint32_t* outNumRequests) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mChanges) {
+        if (!mDevice.prepareAllDisplays()) {
+            return Error::BadDisplay;
+        }
+    } else {
+        ALOGE("Validate was called more than once!");
+    }
+
+    *outNumTypes = mChanges->getNumTypes();
+    *outNumRequests = mChanges->getNumLayerRequests();
+    ALOGV("[%" PRIu64 "] validate --> %u types, %u requests", mId, *outNumTypes,
+            *outNumRequests);
+    for (auto request : mChanges->getTypeChanges()) {
+        ALOGV("Layer %" PRIu64 " --> %s", request.first,
+                to_string(request.second).c_str());
+    }
+    return *outNumTypes > 0 ? Error::HasChanges : Error::None;
+}
+
+Error HWC2On1Adapter::Display::updateLayerZ(hwc2_layer_t layerId, uint32_t z) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    const auto mapLayer = mDevice.mLayers.find(layerId);
+    if (mapLayer == mDevice.mLayers.end()) {
+        ALOGE("[%" PRIu64 "] updateLayerZ failed to find layer", mId);
+        return Error::BadLayer;
+    }
+
+    const auto layer = mapLayer->second;
+    const auto zRange = mLayers.equal_range(layer);
+    bool layerOnDisplay = false;
+    for (auto current = zRange.first; current != zRange.second; ++current) {
+        if (**current == *layer) {
+            if ((*current)->getZ() == z) {
+                // Don't change anything if the Z hasn't changed
+                return Error::None;
+            }
+            current = mLayers.erase(current);
+            layerOnDisplay = true;
+            break;
+        }
+    }
+
+    if (!layerOnDisplay) {
+        ALOGE("[%" PRIu64 "] updateLayerZ failed to find layer on display",
+                mId);
+        return Error::BadLayer;
+    }
+
+    layer->setZ(z);
+    mLayers.emplace(std::move(layer));
+    markGeometryChanged();
+
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Display::getClientTargetSupport(uint32_t width, uint32_t height,
+                                      int32_t format, int32_t dataspace){
+    if (mActiveConfig == nullptr) {
+        return Error::Unsupported;
+    }
+
+    if (width == mActiveConfig->getAttribute(Attribute::Width) &&
+            height == mActiveConfig->getAttribute(Attribute::Height) &&
+            format == HAL_PIXEL_FORMAT_RGBA_8888 &&
+            dataspace == HAL_DATASPACE_UNKNOWN) {
+        return Error::None;
+    }
+
+    return Error::Unsupported;
+}
+
+static constexpr uint32_t ATTRIBUTES_WITH_COLOR[] = {
+    HWC_DISPLAY_VSYNC_PERIOD,
+    HWC_DISPLAY_WIDTH,
+    HWC_DISPLAY_HEIGHT,
+    HWC_DISPLAY_DPI_X,
+    HWC_DISPLAY_DPI_Y,
+    HWC_DISPLAY_COLOR_TRANSFORM,
+    HWC_DISPLAY_NO_ATTRIBUTE,
+};
+
+static constexpr uint32_t ATTRIBUTES_WITHOUT_COLOR[] = {
+    HWC_DISPLAY_VSYNC_PERIOD,
+    HWC_DISPLAY_WIDTH,
+    HWC_DISPLAY_HEIGHT,
+    HWC_DISPLAY_DPI_X,
+    HWC_DISPLAY_DPI_Y,
+    HWC_DISPLAY_NO_ATTRIBUTE,
+};
+
+static constexpr size_t NUM_ATTRIBUTES_WITH_COLOR =
+        sizeof(ATTRIBUTES_WITH_COLOR) / sizeof(uint32_t);
+static_assert(sizeof(ATTRIBUTES_WITH_COLOR) > sizeof(ATTRIBUTES_WITHOUT_COLOR),
+        "Attribute tables have unexpected sizes");
+
+static constexpr uint32_t ATTRIBUTE_MAP_WITH_COLOR[] = {
+    6, // HWC_DISPLAY_NO_ATTRIBUTE = 0
+    0, // HWC_DISPLAY_VSYNC_PERIOD = 1,
+    1, // HWC_DISPLAY_WIDTH = 2,
+    2, // HWC_DISPLAY_HEIGHT = 3,
+    3, // HWC_DISPLAY_DPI_X = 4,
+    4, // HWC_DISPLAY_DPI_Y = 5,
+    5, // HWC_DISPLAY_COLOR_TRANSFORM = 6,
+};
+
+static constexpr uint32_t ATTRIBUTE_MAP_WITHOUT_COLOR[] = {
+    5, // HWC_DISPLAY_NO_ATTRIBUTE = 0
+    0, // HWC_DISPLAY_VSYNC_PERIOD = 1,
+    1, // HWC_DISPLAY_WIDTH = 2,
+    2, // HWC_DISPLAY_HEIGHT = 3,
+    3, // HWC_DISPLAY_DPI_X = 4,
+    4, // HWC_DISPLAY_DPI_Y = 5,
+};
+
+template <uint32_t attribute>
+static constexpr bool attributesMatch()
+{
+    bool match = (attribute ==
+            ATTRIBUTES_WITH_COLOR[ATTRIBUTE_MAP_WITH_COLOR[attribute]]);
+    if (attribute == HWC_DISPLAY_COLOR_TRANSFORM) {
+        return match;
+    }
+
+    return match && (attribute ==
+            ATTRIBUTES_WITHOUT_COLOR[ATTRIBUTE_MAP_WITHOUT_COLOR[attribute]]);
+}
+static_assert(attributesMatch<HWC_DISPLAY_VSYNC_PERIOD>(),
+        "Tables out of sync");
+static_assert(attributesMatch<HWC_DISPLAY_WIDTH>(), "Tables out of sync");
+static_assert(attributesMatch<HWC_DISPLAY_HEIGHT>(), "Tables out of sync");
+static_assert(attributesMatch<HWC_DISPLAY_DPI_X>(), "Tables out of sync");
+static_assert(attributesMatch<HWC_DISPLAY_DPI_Y>(), "Tables out of sync");
+static_assert(attributesMatch<HWC_DISPLAY_COLOR_TRANSFORM>(),
+        "Tables out of sync");
+
+void HWC2On1Adapter::Display::populateConfigs() {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    ALOGV("[%" PRIu64 "] populateConfigs", mId);
+
+    if (mHwc1Id == -1) {
+        ALOGE("populateConfigs: HWC1 ID not set");
+        return;
+    }
+
+    const size_t MAX_NUM_CONFIGS = 128;
+    uint32_t configs[MAX_NUM_CONFIGS] = {};
+    size_t numConfigs = MAX_NUM_CONFIGS;
+    mDevice.mHwc1Device->getDisplayConfigs(mDevice.mHwc1Device, mHwc1Id,
+            configs, &numConfigs);
+
+    for (size_t c = 0; c < numConfigs; ++c) {
+        uint32_t hwc1ConfigId = configs[c];
+        auto newConfig = std::make_shared<Config>(*this);
+
+        int32_t values[NUM_ATTRIBUTES_WITH_COLOR] = {};
+        bool hasColor = true;
+        auto result = mDevice.mHwc1Device->getDisplayAttributes(
+                mDevice.mHwc1Device, mHwc1Id, hwc1ConfigId,
+                ATTRIBUTES_WITH_COLOR, values);
+        if (result != 0) {
+            mDevice.mHwc1Device->getDisplayAttributes(mDevice.mHwc1Device,
+                    mHwc1Id, hwc1ConfigId, ATTRIBUTES_WITHOUT_COLOR, values);
+            hasColor = false;
+        }
+
+        auto attributeMap = hasColor ?
+                ATTRIBUTE_MAP_WITH_COLOR : ATTRIBUTE_MAP_WITHOUT_COLOR;
+
+        newConfig->setAttribute(Attribute::VsyncPeriod,
+                values[attributeMap[HWC_DISPLAY_VSYNC_PERIOD]]);
+        newConfig->setAttribute(Attribute::Width,
+                values[attributeMap[HWC_DISPLAY_WIDTH]]);
+        newConfig->setAttribute(Attribute::Height,
+                values[attributeMap[HWC_DISPLAY_HEIGHT]]);
+        newConfig->setAttribute(Attribute::DpiX,
+                values[attributeMap[HWC_DISPLAY_DPI_X]]);
+        newConfig->setAttribute(Attribute::DpiY,
+                values[attributeMap[HWC_DISPLAY_DPI_Y]]);
+        if (hasColor) {
+            // In HWC1, color modes are referred to as color transforms. To avoid confusion with
+            // the HWC2 concept of color transforms, we internally refer to them as color modes for
+            // both HWC1 and 2.
+            newConfig->setAttribute(ColorMode,
+                    values[attributeMap[HWC_DISPLAY_COLOR_TRANSFORM]]);
+        }
+
+        // We can only do this after attempting to read the color mode
+        newConfig->setHwc1Id(hwc1ConfigId);
+
+        for (auto& existingConfig : mConfigs) {
+            if (existingConfig->merge(*newConfig)) {
+                ALOGV("Merged config %d with existing config %u: %s",
+                        hwc1ConfigId, existingConfig->getId(),
+                        existingConfig->toString().c_str());
+                newConfig.reset();
+                break;
+            }
+        }
+
+        // If it wasn't merged with any existing config, add it to the end
+        if (newConfig) {
+            newConfig->setId(static_cast<hwc2_config_t>(mConfigs.size()));
+            ALOGV("Found new config %u: %s", newConfig->getId(),
+                    newConfig->toString().c_str());
+            mConfigs.emplace_back(std::move(newConfig));
+        }
+    }
+
+    initializeActiveConfig();
+    populateColorModes();
+}
+
+void HWC2On1Adapter::Display::populateConfigs(uint32_t width, uint32_t height) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    mConfigs.emplace_back(std::make_shared<Config>(*this));
+    auto& config = mConfigs[0];
+
+    config->setAttribute(Attribute::Width, static_cast<int32_t>(width));
+    config->setAttribute(Attribute::Height, static_cast<int32_t>(height));
+    config->setHwc1Id(0);
+    config->setId(0);
+    mActiveConfig = config;
+}
+
+bool HWC2On1Adapter::Display::prepare() {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    // Only prepare display contents for displays HWC1 knows about
+    if (mHwc1Id == -1) {
+        return true;
+    }
+
+    // It doesn't make sense to prepare a display for which there is no active
+    // config, so return early
+    if (!mActiveConfig) {
+        ALOGE("[%" PRIu64 "] Attempted to prepare, but no config active", mId);
+        return false;
+    }
+
+    allocateRequestedContents();
+    assignHwc1LayerIds();
+
+    mHwc1RequestedContents->retireFenceFd = -1;
+    mHwc1RequestedContents->flags = 0;
+    if (mGeometryChanged) {
+        mHwc1RequestedContents->flags |= HWC_GEOMETRY_CHANGED;
+    }
+    mHwc1RequestedContents->outbuf = mOutputBuffer.getBuffer();
+    mHwc1RequestedContents->outbufAcquireFenceFd = mOutputBuffer.getFence();
+
+    // +1 is for framebuffer target layer.
+    mHwc1RequestedContents->numHwLayers = mLayers.size() + 1;
+    for (auto& layer : mLayers) {
+        auto& hwc1Layer = mHwc1RequestedContents->hwLayers[layer->getHwc1Id()];
+        hwc1Layer.releaseFenceFd = -1;
+        hwc1Layer.acquireFenceFd = -1;
+        ALOGV("Applying states for layer %" PRIu64 " ", layer->getId());
+        layer->applyState(hwc1Layer);
+    }
+
+    prepareFramebufferTarget();
+
+    resetGeometryMarker();
+
+    return true;
+}
+
+void HWC2On1Adapter::Display::generateChanges() {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    mChanges.reset(new Changes);
+
+    size_t numLayers = mHwc1RequestedContents->numHwLayers;
+    for (size_t hwc1Id = 0; hwc1Id < numLayers; ++hwc1Id) {
+        const auto& receivedLayer = mHwc1RequestedContents->hwLayers[hwc1Id];
+        if (mHwc1LayerMap.count(hwc1Id) == 0) {
+            ALOGE_IF(receivedLayer.compositionType != HWC_FRAMEBUFFER_TARGET,
+                    "generateChanges: HWC1 layer %zd doesn't have a"
+                    " matching HWC2 layer, and isn't the framebuffer target",
+                    hwc1Id);
+            continue;
+        }
+
+        Layer& layer = *mHwc1LayerMap[hwc1Id];
+        updateTypeChanges(receivedLayer, layer);
+        updateLayerRequests(receivedLayer, layer);
+    }
+}
+
+bool HWC2On1Adapter::Display::hasChanges() const {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+    return mChanges != nullptr;
+}
+
+Error HWC2On1Adapter::Display::set(hwc_display_contents_1& hwcContents) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    if (!mChanges || (mChanges->getNumTypes() > 0)) {
+        ALOGE("[%" PRIu64 "] set failed: not validated", mId);
+        return Error::NotValidated;
+    }
+
+    // Set up the client/framebuffer target
+    auto numLayers = hwcContents.numHwLayers;
+
+    // Close acquire fences on FRAMEBUFFER layers, since they will not be used
+    // by HWC
+    for (size_t l = 0; l < numLayers - 1; ++l) {
+        auto& layer = hwcContents.hwLayers[l];
+        if (layer.compositionType == HWC_FRAMEBUFFER) {
+            ALOGV("Closing fence %d for layer %zd", layer.acquireFenceFd, l);
+            close(layer.acquireFenceFd);
+            layer.acquireFenceFd = -1;
+        }
+    }
+
+    auto& clientTargetLayer = hwcContents.hwLayers[numLayers - 1];
+    if (clientTargetLayer.compositionType == HWC_FRAMEBUFFER_TARGET) {
+        clientTargetLayer.handle = mClientTarget.getBuffer();
+        clientTargetLayer.acquireFenceFd = mClientTarget.getFence();
+    } else {
+        ALOGE("[%" PRIu64 "] set: last HWC layer wasn't FRAMEBUFFER_TARGET",
+                mId);
+    }
+
+    mChanges.reset();
+
+    return Error::None;
+}
+
+void HWC2On1Adapter::Display::addRetireFence(int fenceFd) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+    mRetireFence.add(fenceFd);
+}
+
+void HWC2On1Adapter::Display::addReleaseFences(
+        const hwc_display_contents_1_t& hwcContents) {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    size_t numLayers = hwcContents.numHwLayers;
+    for (size_t hwc1Id = 0; hwc1Id < numLayers; ++hwc1Id) {
+        const auto& receivedLayer = hwcContents.hwLayers[hwc1Id];
+        if (mHwc1LayerMap.count(hwc1Id) == 0) {
+            if (receivedLayer.compositionType != HWC_FRAMEBUFFER_TARGET) {
+                ALOGE("addReleaseFences: HWC1 layer %zd doesn't have a"
+                        " matching HWC2 layer, and isn't the framebuffer"
+                        " target", hwc1Id);
+            }
+            // Close the framebuffer target release fence since we will use the
+            // display retire fence instead
+            if (receivedLayer.releaseFenceFd != -1) {
+                close(receivedLayer.releaseFenceFd);
+            }
+            continue;
+        }
+
+        Layer& layer = *mHwc1LayerMap[hwc1Id];
+        ALOGV("Adding release fence %d to layer %" PRIu64,
+                receivedLayer.releaseFenceFd, layer.getId());
+        layer.addReleaseFence(receivedLayer.releaseFenceFd);
+    }
+}
+
+bool HWC2On1Adapter::Display::hasColorTransform() const {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+    return mHasColorTransform;
+}
+
+static std::string hwc1CompositionString(int32_t type) {
+    switch (type) {
+        case HWC_FRAMEBUFFER: return "Framebuffer";
+        case HWC_OVERLAY: return "Overlay";
+        case HWC_BACKGROUND: return "Background";
+        case HWC_FRAMEBUFFER_TARGET: return "FramebufferTarget";
+        case HWC_SIDEBAND: return "Sideband";
+        case HWC_CURSOR_OVERLAY: return "CursorOverlay";
+        default:
+            return std::string("Unknown (") + std::to_string(type) + ")";
+    }
+}
+
+static std::string hwc1TransformString(int32_t transform) {
+    switch (transform) {
+        case 0: return "None";
+        case HWC_TRANSFORM_FLIP_H: return "FlipH";
+        case HWC_TRANSFORM_FLIP_V: return "FlipV";
+        case HWC_TRANSFORM_ROT_90: return "Rotate90";
+        case HWC_TRANSFORM_ROT_180: return "Rotate180";
+        case HWC_TRANSFORM_ROT_270: return "Rotate270";
+        case HWC_TRANSFORM_FLIP_H_ROT_90: return "FlipHRotate90";
+        case HWC_TRANSFORM_FLIP_V_ROT_90: return "FlipVRotate90";
+        default:
+            return std::string("Unknown (") + std::to_string(transform) + ")";
+    }
+}
+
+static std::string hwc1BlendModeString(int32_t mode) {
+    switch (mode) {
+        case HWC_BLENDING_NONE: return "None";
+        case HWC_BLENDING_PREMULT: return "Premultiplied";
+        case HWC_BLENDING_COVERAGE: return "Coverage";
+        default:
+            return std::string("Unknown (") + std::to_string(mode) + ")";
+    }
+}
+
+static std::string rectString(hwc_rect_t rect) {
+    std::stringstream output;
+    output << "[" << rect.left << ", " << rect.top << ", ";
+    output << rect.right << ", " << rect.bottom << "]";
+    return output.str();
+}
+
+static std::string approximateFloatString(float f) {
+    if (static_cast<int32_t>(f) == f) {
+        return std::to_string(static_cast<int32_t>(f));
+    }
+    int32_t truncated = static_cast<int32_t>(f * 10);
+    bool approximate = (static_cast<float>(truncated) != f * 10);
+    const size_t BUFFER_SIZE = 32;
+    char buffer[BUFFER_SIZE] = {};
+    auto bytesWritten = snprintf(buffer, BUFFER_SIZE,
+            "%s%.1f", approximate ? "~" : "", f);
+    return std::string(buffer, bytesWritten);
+}
+
+static std::string frectString(hwc_frect_t frect) {
+    std::stringstream output;
+    output << "[" << approximateFloatString(frect.left) << ", ";
+    output << approximateFloatString(frect.top) << ", ";
+    output << approximateFloatString(frect.right) << ", ";
+    output << approximateFloatString(frect.bottom) << "]";
+    return output.str();
+}
+
+static std::string colorString(hwc_color_t color) {
+    std::stringstream output;
+    output << "RGBA [";
+    output << static_cast<int32_t>(color.r) << ", ";
+    output << static_cast<int32_t>(color.g) << ", ";
+    output << static_cast<int32_t>(color.b) << ", ";
+    output << static_cast<int32_t>(color.a) << "]";
+    return output.str();
+}
+
+static std::string alphaString(float f) {
+    const size_t BUFFER_SIZE = 8;
+    char buffer[BUFFER_SIZE] = {};
+    auto bytesWritten = snprintf(buffer, BUFFER_SIZE, "%.3f", f);
+    return std::string(buffer, bytesWritten);
+}
+
+static std::string to_string(const hwc_layer_1_t& hwcLayer,
+        int32_t hwc1MinorVersion) {
+    const char* fill = "          ";
+
+    std::stringstream output;
+
+    output << "  Composition: " <<
+            hwc1CompositionString(hwcLayer.compositionType);
+
+    if (hwcLayer.compositionType == HWC_BACKGROUND) {
+        output << "  Color: " << colorString(hwcLayer.backgroundColor) << '\n';
+    } else if (hwcLayer.compositionType == HWC_SIDEBAND) {
+        output << "  Stream: " << hwcLayer.sidebandStream << '\n';
+    } else {
+        output << "  Buffer: " << hwcLayer.handle << "/" <<
+                hwcLayer.acquireFenceFd << '\n';
+    }
+
+    output << fill << "Display frame: " << rectString(hwcLayer.displayFrame) <<
+            '\n';
+
+    output << fill << "Source crop: ";
+    if (hwc1MinorVersion >= 3) {
+        output << frectString(hwcLayer.sourceCropf) << '\n';
+    } else {
+        output << rectString(hwcLayer.sourceCropi) << '\n';
+    }
+
+    output << fill << "Transform: " << hwc1TransformString(hwcLayer.transform);
+    output << "  Blend mode: " << hwc1BlendModeString(hwcLayer.blending);
+    if (hwcLayer.planeAlpha != 0xFF) {
+        output << "  Alpha: " << alphaString(hwcLayer.planeAlpha / 255.0f);
+    }
+    output << '\n';
+
+    if (hwcLayer.hints != 0) {
+        output << fill << "Hints:";
+        if ((hwcLayer.hints & HWC_HINT_TRIPLE_BUFFER) != 0) {
+            output << " TripleBuffer";
+        }
+        if ((hwcLayer.hints & HWC_HINT_CLEAR_FB) != 0) {
+            output << " ClearFB";
+        }
+        output << '\n';
+    }
+
+    if (hwcLayer.flags != 0) {
+        output << fill << "Flags:";
+        if ((hwcLayer.flags & HWC_SKIP_LAYER) != 0) {
+            output << " SkipLayer";
+        }
+        if ((hwcLayer.flags & HWC_IS_CURSOR_LAYER) != 0) {
+            output << " IsCursorLayer";
+        }
+        output << '\n';
+    }
+
+    return output.str();
+}
+
+static std::string to_string(const hwc_display_contents_1_t& hwcContents,
+        int32_t hwc1MinorVersion) {
+    const char* fill = "      ";
+
+    std::stringstream output;
+    output << fill << "Geometry changed: " <<
+            ((hwcContents.flags & HWC_GEOMETRY_CHANGED) != 0 ? "Y\n" : "N\n");
+
+    output << fill << hwcContents.numHwLayers << " Layer" <<
+            ((hwcContents.numHwLayers == 1) ? "\n" : "s\n");
+    for (size_t layer = 0; layer < hwcContents.numHwLayers; ++layer) {
+        output << fill << "  Layer " << layer;
+        output << to_string(hwcContents.hwLayers[layer], hwc1MinorVersion);
+    }
+
+    if (hwcContents.outbuf != nullptr) {
+        output << fill << "Output buffer: " << hwcContents.outbuf << "/" <<
+                hwcContents.outbufAcquireFenceFd << '\n';
+    }
+
+    return output.str();
+}
+
+std::string HWC2On1Adapter::Display::dump() const {
+    std::unique_lock<std::recursive_mutex> lock(mStateMutex);
+
+    std::stringstream output;
+
+    output << "  Display " << mId << ": ";
+    output << to_string(mType) << "  ";
+    output << "HWC1 ID: " << mHwc1Id << "  ";
+    output << "Power mode: " << to_string(mPowerMode) << "  ";
+    output << "Vsync: " << to_string(mVsyncEnabled) << '\n';
+
+    output << "    Color modes [active]:";
+    for (const auto& mode : mColorModes) {
+        if (mode == mActiveColorMode) {
+            output << " [" << mode << ']';
+        } else {
+            output << " " << mode;
+        }
+    }
+    output << '\n';
+
+    output << "    " << mConfigs.size() << " Config" <<
+            (mConfigs.size() == 1 ? "" : "s") << " (* active)\n";
+    for (const auto& config : mConfigs) {
+        output << (config == mActiveConfig ? "    * " : "      ");
+        output << config->toString(true) << '\n';
+    }
+
+    output << "    " << mLayers.size() << " Layer" <<
+            (mLayers.size() == 1 ? "" : "s") << '\n';
+    for (const auto& layer : mLayers) {
+        output << layer->dump();
+    }
+
+    output << "    Client target: " << mClientTarget.getBuffer() << '\n';
+
+    if (mOutputBuffer.getBuffer() != nullptr) {
+        output << "    Output buffer: " << mOutputBuffer.getBuffer() << '\n';
+    }
+
+    if (mHwc1RequestedContents) {
+        output << "    Last requested HWC1 state\n";
+        output << to_string(*mHwc1RequestedContents, mDevice.mHwc1MinorVersion);
+    }
+
+    return output.str();
+}
+
+hwc_rect_t* HWC2On1Adapter::Display::GetRects(size_t numRects) {
+    if (numRects == 0) {
+        return nullptr;
+    }
+
+    if (numRects > mNumAvailableRects) {
+        // This should NEVER happen since we calculated how many rects the
+        // display would need.
+        ALOGE("Rect allocation failure! SF is likely to crash soon!");
+        return nullptr;
+
+    }
+    hwc_rect_t* rects = mNextAvailableRect;
+    mNextAvailableRect += numRects;
+    mNumAvailableRects -= numRects;
+    return rects;
+}
+
+hwc_display_contents_1* HWC2On1Adapter::Display::getDisplayContents() {
+    return mHwc1RequestedContents.get();
+}
+
+void HWC2On1Adapter::Display::Config::setAttribute(HWC2::Attribute attribute,
+        int32_t value) {
+    mAttributes[attribute] = value;
+}
+
+int32_t HWC2On1Adapter::Display::Config::getAttribute(Attribute attribute) const {
+    if (mAttributes.count(attribute) == 0) {
+        return -1;
+    }
+    return mAttributes.at(attribute);
+}
+
+void HWC2On1Adapter::Display::Config::setHwc1Id(uint32_t id) {
+    android_color_mode_t colorMode = static_cast<android_color_mode_t>(getAttribute(ColorMode));
+    mHwc1Ids.emplace(colorMode, id);
+}
+
+bool HWC2On1Adapter::Display::Config::hasHwc1Id(uint32_t id) const {
+    for (const auto& idPair : mHwc1Ids) {
+        if (id == idPair.second) {
+            return true;
+        }
+    }
+    return false;
+}
+
+Error HWC2On1Adapter::Display::Config::getColorModeForHwc1Id(
+        uint32_t id, android_color_mode_t* outMode) const {
+    for (const auto& idPair : mHwc1Ids) {
+        if (id == idPair.second) {
+            *outMode = idPair.first;
+            return Error::None;
+        }
+    }
+    ALOGE("Unable to find color mode for HWC ID %" PRIu32 " on config %u", id, mId);
+    return Error::BadParameter;
+}
+
+Error HWC2On1Adapter::Display::Config::getHwc1IdForColorMode(android_color_mode_t mode,
+        uint32_t* outId) const {
+    for (const auto& idPair : mHwc1Ids) {
+        if (mode == idPair.first) {
+            *outId = idPair.second;
+            return Error::None;
+        }
+    }
+    ALOGE("Unable to find HWC1 ID for color mode %d on config %u", mode, mId);
+    return Error::BadParameter;
+}
+
+bool HWC2On1Adapter::Display::Config::merge(const Config& other) {
+    auto attributes = {HWC2::Attribute::Width, HWC2::Attribute::Height,
+            HWC2::Attribute::VsyncPeriod, HWC2::Attribute::DpiX,
+            HWC2::Attribute::DpiY};
+    for (auto attribute : attributes) {
+        if (getAttribute(attribute) != other.getAttribute(attribute)) {
+            return false;
+        }
+    }
+    android_color_mode_t otherColorMode =
+            static_cast<android_color_mode_t>(other.getAttribute(ColorMode));
+    if (mHwc1Ids.count(otherColorMode) != 0) {
+        ALOGE("Attempted to merge two configs (%u and %u) which appear to be "
+                "identical", mHwc1Ids.at(otherColorMode),
+                other.mHwc1Ids.at(otherColorMode));
+        return false;
+    }
+    mHwc1Ids.emplace(otherColorMode,
+            other.mHwc1Ids.at(otherColorMode));
+    return true;
+}
+
+std::set<android_color_mode_t> HWC2On1Adapter::Display::Config::getColorModes() const {
+    std::set<android_color_mode_t> colorModes;
+    for (const auto& idPair : mHwc1Ids) {
+        colorModes.emplace(idPair.first);
+    }
+    return colorModes;
+}
+
+std::string HWC2On1Adapter::Display::Config::toString(bool splitLine) const {
+    std::string output;
+
+    const size_t BUFFER_SIZE = 100;
+    char buffer[BUFFER_SIZE] = {};
+    auto writtenBytes = snprintf(buffer, BUFFER_SIZE,
+            "%u x %u", mAttributes.at(HWC2::Attribute::Width),
+            mAttributes.at(HWC2::Attribute::Height));
+    output.append(buffer, writtenBytes);
+
+    if (mAttributes.count(HWC2::Attribute::VsyncPeriod) != 0) {
+        std::memset(buffer, 0, BUFFER_SIZE);
+        writtenBytes = snprintf(buffer, BUFFER_SIZE, " @ %.1f Hz",
+                1e9 / mAttributes.at(HWC2::Attribute::VsyncPeriod));
+        output.append(buffer, writtenBytes);
+    }
+
+    if (mAttributes.count(HWC2::Attribute::DpiX) != 0 &&
+            mAttributes.at(HWC2::Attribute::DpiX) != -1) {
+        std::memset(buffer, 0, BUFFER_SIZE);
+        writtenBytes = snprintf(buffer, BUFFER_SIZE,
+                ", DPI: %.1f x %.1f",
+                mAttributes.at(HWC2::Attribute::DpiX) / 1000.0f,
+                mAttributes.at(HWC2::Attribute::DpiY) / 1000.0f);
+        output.append(buffer, writtenBytes);
+    }
+
+    std::memset(buffer, 0, BUFFER_SIZE);
+    if (splitLine) {
+        writtenBytes = snprintf(buffer, BUFFER_SIZE,
+                "\n        HWC1 ID/Color transform:");
+    } else {
+        writtenBytes = snprintf(buffer, BUFFER_SIZE,
+                ", HWC1 ID/Color transform:");
+    }
+    output.append(buffer, writtenBytes);
+
+
+    for (const auto& id : mHwc1Ids) {
+        android_color_mode_t colorMode = id.first;
+        uint32_t hwc1Id = id.second;
+        std::memset(buffer, 0, BUFFER_SIZE);
+        if (colorMode == mDisplay.mActiveColorMode) {
+            writtenBytes = snprintf(buffer, BUFFER_SIZE, " [%u/%d]", hwc1Id,
+                    colorMode);
+        } else {
+            writtenBytes = snprintf(buffer, BUFFER_SIZE, " %u/%d", hwc1Id,
+                    colorMode);
+        }
+        output.append(buffer, writtenBytes);
+    }
+
+    return output;
+}
+
+std::shared_ptr<const HWC2On1Adapter::Display::Config>
+        HWC2On1Adapter::Display::getConfig(hwc2_config_t configId) const {
+    if (configId > mConfigs.size() || !mConfigs[configId]->isOnDisplay(*this)) {
+        return nullptr;
+    }
+    return mConfigs[configId];
+}
+
+void HWC2On1Adapter::Display::populateColorModes() {
+    mColorModes = mConfigs[0]->getColorModes();
+    for (const auto& config : mConfigs) {
+        std::set<android_color_mode_t> intersection;
+        auto configModes = config->getColorModes();
+        std::set_intersection(mColorModes.cbegin(), mColorModes.cend(),
+                configModes.cbegin(), configModes.cend(),
+                std::inserter(intersection, intersection.begin()));
+        std::swap(intersection, mColorModes);
+    }
+}
+
+void HWC2On1Adapter::Display::initializeActiveConfig() {
+    if (mDevice.mHwc1Device->getActiveConfig == nullptr) {
+        ALOGV("getActiveConfig is null, choosing config 0");
+        mActiveConfig = mConfigs[0];
+        mActiveColorMode = HAL_COLOR_MODE_NATIVE;
+        return;
+    }
+
+    auto activeConfig = mDevice.mHwc1Device->getActiveConfig(
+            mDevice.mHwc1Device, mHwc1Id);
+
+    // Some devices startup without an activeConfig:
+    // We need to set one ourselves.
+    if (activeConfig == HWC_ERROR) {
+        ALOGV("There is no active configuration: Picking the first one: 0.");
+        const int defaultIndex = 0;
+        mDevice.mHwc1Device->setActiveConfig(mDevice.mHwc1Device, mHwc1Id, defaultIndex);
+        activeConfig = defaultIndex;
+    }
+
+    for (const auto& config : mConfigs) {
+        if (config->hasHwc1Id(activeConfig)) {
+            ALOGE("Setting active config to %d for HWC1 config %u", config->getId(), activeConfig);
+            mActiveConfig = config;
+            if (config->getColorModeForHwc1Id(activeConfig, &mActiveColorMode) != Error::None) {
+                // This should never happen since we checked for the config's presence before
+                // setting it as active.
+                ALOGE("Unable to find color mode for active HWC1 config %d", config->getId());
+                mActiveColorMode = HAL_COLOR_MODE_NATIVE;
+            }
+            break;
+        }
+    }
+    if (!mActiveConfig) {
+        ALOGV("Unable to find active HWC1 config %u, defaulting to "
+                "config 0", activeConfig);
+        mActiveConfig = mConfigs[0];
+        mActiveColorMode = HAL_COLOR_MODE_NATIVE;
+    }
+
+
+
+
+}
+
+void HWC2On1Adapter::Display::allocateRequestedContents() {
+    // What needs to be allocated:
+    // 1 hwc_display_contents_1_t
+    // 1 hwc_layer_1_t for each layer
+    // 1 hwc_rect_t for each layer's surfaceDamage
+    // 1 hwc_rect_t for each layer's visibleRegion
+    // 1 hwc_layer_1_t for the framebuffer
+    // 1 hwc_rect_t for the framebuffer's visibleRegion
+
+    // Count # of surfaceDamage
+    size_t numSurfaceDamages = 0;
+    for (const auto& layer : mLayers) {
+        numSurfaceDamages += layer->getNumSurfaceDamages();
+    }
+
+    // Count # of visibleRegions (start at 1 for mandatory framebuffer target
+    // region)
+    size_t numVisibleRegion = 1;
+    for (const auto& layer : mLayers) {
+        numVisibleRegion += layer->getNumVisibleRegions();
+    }
+
+    size_t numRects = numVisibleRegion + numSurfaceDamages;
+    auto numLayers = mLayers.size() + 1;
+    size_t size = sizeof(hwc_display_contents_1_t) +
+            sizeof(hwc_layer_1_t) * numLayers +
+            sizeof(hwc_rect_t) * numRects;
+    auto contents = static_cast<hwc_display_contents_1_t*>(std::calloc(size, 1));
+    mHwc1RequestedContents.reset(contents);
+    mNextAvailableRect = reinterpret_cast<hwc_rect_t*>(&contents->hwLayers[numLayers]);
+    mNumAvailableRects = numRects;
+}
+
+void HWC2On1Adapter::Display::assignHwc1LayerIds() {
+    mHwc1LayerMap.clear();
+    size_t nextHwc1Id = 0;
+    for (auto& layer : mLayers) {
+        mHwc1LayerMap[nextHwc1Id] = layer;
+        layer->setHwc1Id(nextHwc1Id++);
+    }
+}
+
+void HWC2On1Adapter::Display::updateTypeChanges(const hwc_layer_1_t& hwc1Layer,
+        const Layer& layer) {
+    auto layerId = layer.getId();
+    switch (hwc1Layer.compositionType) {
+        case HWC_FRAMEBUFFER:
+            if (layer.getCompositionType() != Composition::Client) {
+                mChanges->addTypeChange(layerId, Composition::Client);
+            }
+            break;
+        case HWC_OVERLAY:
+            if (layer.getCompositionType() != Composition::Device) {
+                mChanges->addTypeChange(layerId, Composition::Device);
+            }
+            break;
+        case HWC_BACKGROUND:
+            ALOGE_IF(layer.getCompositionType() != Composition::SolidColor,
+                    "updateTypeChanges: HWC1 requested BACKGROUND, but HWC2"
+                    " wasn't expecting SolidColor");
+            break;
+        case HWC_FRAMEBUFFER_TARGET:
+            // Do nothing, since it shouldn't be modified by HWC1
+            break;
+        case HWC_SIDEBAND:
+            ALOGE_IF(layer.getCompositionType() != Composition::Sideband,
+                    "updateTypeChanges: HWC1 requested SIDEBAND, but HWC2"
+                    " wasn't expecting Sideband");
+            break;
+        case HWC_CURSOR_OVERLAY:
+            ALOGE_IF(layer.getCompositionType() != Composition::Cursor,
+                    "updateTypeChanges: HWC1 requested CURSOR_OVERLAY, but"
+                    " HWC2 wasn't expecting Cursor");
+            break;
+    }
+}
+
+void HWC2On1Adapter::Display::updateLayerRequests(
+        const hwc_layer_1_t& hwc1Layer, const Layer& layer) {
+    if ((hwc1Layer.hints & HWC_HINT_CLEAR_FB) != 0) {
+        mChanges->addLayerRequest(layer.getId(),
+                LayerRequest::ClearClientTarget);
+    }
+}
+
+void HWC2On1Adapter::Display::prepareFramebufferTarget() {
+    // We check that mActiveConfig is valid in Display::prepare
+    int32_t width = mActiveConfig->getAttribute(Attribute::Width);
+    int32_t height = mActiveConfig->getAttribute(Attribute::Height);
+
+    auto& hwc1Target = mHwc1RequestedContents->hwLayers[mLayers.size()];
+    hwc1Target.compositionType = HWC_FRAMEBUFFER_TARGET;
+    hwc1Target.releaseFenceFd = -1;
+    hwc1Target.hints = 0;
+    hwc1Target.flags = 0;
+    hwc1Target.transform = 0;
+    hwc1Target.blending = HWC_BLENDING_PREMULT;
+    if (mDevice.getHwc1MinorVersion() < 3) {
+        hwc1Target.sourceCropi = {0, 0, width, height};
+    } else {
+        hwc1Target.sourceCropf = {0.0f, 0.0f, static_cast<float>(width),
+                static_cast<float>(height)};
+    }
+    hwc1Target.displayFrame = {0, 0, width, height};
+    hwc1Target.planeAlpha = 255;
+
+    hwc1Target.visibleRegionScreen.numRects = 1;
+    hwc_rect_t* rects = GetRects(1);
+    rects[0].left = 0;
+    rects[0].top = 0;
+    rects[0].right = width;
+    rects[0].bottom = height;
+    hwc1Target.visibleRegionScreen.rects = rects;
+
+    // We will set this to the correct value in set
+    hwc1Target.acquireFenceFd = -1;
+}
+
+// Layer functions
+
+std::atomic<hwc2_layer_t> HWC2On1Adapter::Layer::sNextId(1);
+
+HWC2On1Adapter::Layer::Layer(Display& display)
+  : mId(sNextId++),
+    mDisplay(display),
+    mBuffer(),
+    mSurfaceDamage(),
+    mBlendMode(BlendMode::None),
+    mColor({0, 0, 0, 0}),
+    mCompositionType(Composition::Invalid),
+    mDisplayFrame({0, 0, -1, -1}),
+    mPlaneAlpha(0.0f),
+    mSidebandStream(nullptr),
+    mSourceCrop({0.0f, 0.0f, -1.0f, -1.0f}),
+    mTransform(Transform::None),
+    mVisibleRegion(),
+    mZ(0),
+    mReleaseFence(),
+    mHwc1Id(0),
+    mHasUnsupportedPlaneAlpha(false) {}
+
+bool HWC2On1Adapter::SortLayersByZ::operator()(
+        const std::shared_ptr<Layer>& lhs, const std::shared_ptr<Layer>& rhs) {
+    return lhs->getZ() < rhs->getZ();
+}
+
+Error HWC2On1Adapter::Layer::setBuffer(buffer_handle_t buffer,
+        int32_t acquireFence) {
+    ALOGV("Setting acquireFence to %d for layer %" PRIu64, acquireFence, mId);
+    mBuffer.setBuffer(buffer);
+    mBuffer.setFence(acquireFence);
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setCursorPosition(int32_t x, int32_t y) {
+    if (mCompositionType != Composition::Cursor) {
+        return Error::BadLayer;
+    }
+
+    if (mDisplay.hasChanges()) {
+        return Error::NotValidated;
+    }
+
+    auto displayId = mDisplay.getHwc1Id();
+    auto hwc1Device = mDisplay.getDevice().getHwc1Device();
+    hwc1Device->setCursorPositionAsync(hwc1Device, displayId, x, y);
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setSurfaceDamage(hwc_region_t damage) {
+    // HWC1 supports surface damage starting only with version 1.5.
+    if (mDisplay.getDevice().mHwc1MinorVersion < 5) {
+        return Error::None;
+    }
+    mSurfaceDamage.resize(damage.numRects);
+    std::copy_n(damage.rects, damage.numRects, mSurfaceDamage.begin());
+    return Error::None;
+}
+
+// Layer state functions
+
+Error HWC2On1Adapter::Layer::setBlendMode(BlendMode mode) {
+    mBlendMode = mode;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setColor(hwc_color_t color) {
+    mColor = color;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setCompositionType(Composition type) {
+    mCompositionType = type;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setDataspace(android_dataspace_t) {
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setDisplayFrame(hwc_rect_t frame) {
+    mDisplayFrame = frame;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setPlaneAlpha(float alpha) {
+    mPlaneAlpha = alpha;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setSidebandStream(const native_handle_t* stream) {
+    mSidebandStream = stream;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setSourceCrop(hwc_frect_t crop) {
+    mSourceCrop = crop;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setTransform(Transform transform) {
+    mTransform = transform;
+    mDisplay.markGeometryChanged();
+    return Error::None;
+}
+
+static bool compareRects(const hwc_rect_t& rect1, const hwc_rect_t& rect2) {
+    return rect1.left == rect2.left &&
+            rect1.right == rect2.right &&
+            rect1.top == rect2.top &&
+            rect1.bottom == rect2.bottom;
+}
+
+Error HWC2On1Adapter::Layer::setVisibleRegion(hwc_region_t visible) {
+    if ((getNumVisibleRegions() != visible.numRects) ||
+        !std::equal(mVisibleRegion.begin(), mVisibleRegion.end(), visible.rects,
+                    compareRects)) {
+        mVisibleRegion.resize(visible.numRects);
+        std::copy_n(visible.rects, visible.numRects, mVisibleRegion.begin());
+        mDisplay.markGeometryChanged();
+    }
+    return Error::None;
+}
+
+Error HWC2On1Adapter::Layer::setZ(uint32_t z) {
+    mZ = z;
+    return Error::None;
+}
+
+void HWC2On1Adapter::Layer::addReleaseFence(int fenceFd) {
+    ALOGV("addReleaseFence %d to layer %" PRIu64, fenceFd, mId);
+    mReleaseFence.add(fenceFd);
+}
+
+const sp<MiniFence>& HWC2On1Adapter::Layer::getReleaseFence() const {
+    return mReleaseFence.get();
+}
+
+void HWC2On1Adapter::Layer::applyState(hwc_layer_1_t& hwc1Layer) {
+    applyCommonState(hwc1Layer);
+    applyCompositionType(hwc1Layer);
+    switch (mCompositionType) {
+        case Composition::SolidColor : applySolidColorState(hwc1Layer); break;
+        case Composition::Sideband : applySidebandState(hwc1Layer); break;
+        default: applyBufferState(hwc1Layer); break;
+    }
+}
+
+static std::string regionStrings(const std::vector<hwc_rect_t>& visibleRegion,
+        const std::vector<hwc_rect_t>& surfaceDamage) {
+    std::string regions;
+    regions += "        Visible Region";
+    regions.resize(40, ' ');
+    regions += "Surface Damage\n";
+
+    size_t numPrinted = 0;
+    size_t maxSize = std::max(visibleRegion.size(), surfaceDamage.size());
+    while (numPrinted < maxSize) {
+        std::string line("        ");
+        if (visibleRegion.empty() && numPrinted == 0) {
+            line += "None";
+        } else if (numPrinted < visibleRegion.size()) {
+            line += rectString(visibleRegion[numPrinted]);
+        }
+        line.resize(40, ' ');
+        if (surfaceDamage.empty() && numPrinted == 0) {
+            line += "None";
+        } else if (numPrinted < surfaceDamage.size()) {
+            line += rectString(surfaceDamage[numPrinted]);
+        }
+        line += '\n';
+        regions += line;
+        ++numPrinted;
+    }
+    return regions;
+}
+
+std::string HWC2On1Adapter::Layer::dump() const {
+    std::stringstream output;
+    const char* fill = "      ";
+
+    output << fill << to_string(mCompositionType);
+    output << " Layer  HWC2/1: " << mId << "/" << mHwc1Id << "  ";
+    output << "Z: " << mZ;
+    if (mCompositionType == HWC2::Composition::SolidColor) {
+        output << "  " << colorString(mColor);
+    } else if (mCompositionType == HWC2::Composition::Sideband) {
+        output << "  Handle: " << mSidebandStream << '\n';
+    } else {
+        output << "  Buffer: " << mBuffer.getBuffer() << "/" <<
+                mBuffer.getFence() << '\n';
+        output << fill << "  Display frame [LTRB]: " <<
+                rectString(mDisplayFrame) << '\n';
+        output << fill << "  Source crop: " <<
+                frectString(mSourceCrop) << '\n';
+        output << fill << "  Transform: " << to_string(mTransform);
+        output << "  Blend mode: " << to_string(mBlendMode);
+        if (mPlaneAlpha != 1.0f) {
+            output << "  Alpha: " <<
+                alphaString(mPlaneAlpha) << '\n';
+        } else {
+            output << '\n';
+        }
+        output << regionStrings(mVisibleRegion, mSurfaceDamage);
+    }
+    return output.str();
+}
+
+static int getHwc1Blending(HWC2::BlendMode blendMode) {
+    switch (blendMode) {
+        case BlendMode::Coverage: return HWC_BLENDING_COVERAGE;
+        case BlendMode::Premultiplied: return HWC_BLENDING_PREMULT;
+        default: return HWC_BLENDING_NONE;
+    }
+}
+
+void HWC2On1Adapter::Layer::applyCommonState(hwc_layer_1_t& hwc1Layer) {
+    auto minorVersion = mDisplay.getDevice().getHwc1MinorVersion();
+    hwc1Layer.blending = getHwc1Blending(mBlendMode);
+    hwc1Layer.displayFrame = mDisplayFrame;
+
+    auto pendingAlpha = mPlaneAlpha;
+    if (minorVersion < 2) {
+        mHasUnsupportedPlaneAlpha = pendingAlpha < 1.0f;
+    } else {
+        hwc1Layer.planeAlpha =
+                static_cast<uint8_t>(255.0f * pendingAlpha + 0.5f);
+    }
+
+    if (minorVersion < 3) {
+        auto pending = mSourceCrop;
+        hwc1Layer.sourceCropi.left =
+                static_cast<int32_t>(std::ceil(pending.left));
+        hwc1Layer.sourceCropi.top =
+                static_cast<int32_t>(std::ceil(pending.top));
+        hwc1Layer.sourceCropi.right =
+                static_cast<int32_t>(std::floor(pending.right));
+        hwc1Layer.sourceCropi.bottom =
+                static_cast<int32_t>(std::floor(pending.bottom));
+    } else {
+        hwc1Layer.sourceCropf = mSourceCrop;
+    }
+
+    hwc1Layer.transform = static_cast<uint32_t>(mTransform);
+
+    auto& hwc1VisibleRegion = hwc1Layer.visibleRegionScreen;
+    hwc1VisibleRegion.numRects = mVisibleRegion.size();
+    hwc_rect_t* rects = mDisplay.GetRects(hwc1VisibleRegion.numRects);
+    hwc1VisibleRegion.rects = rects;
+    for (size_t i = 0; i < mVisibleRegion.size(); i++) {
+        rects[i] = mVisibleRegion[i];
+    }
+}
+
+void HWC2On1Adapter::Layer::applySolidColorState(hwc_layer_1_t& hwc1Layer) {
+    // If the device does not support background color it is likely to make
+    // assumption regarding backgroundColor and handle (both fields occupy
+    // the same location in hwc_layer_1_t union).
+    // To not confuse these devices we don't set background color and we
+    // make sure handle is a null pointer.
+    if (hasUnsupportedBackgroundColor()) {
+        hwc1Layer.handle = nullptr;
+    } else {
+        hwc1Layer.backgroundColor = mColor;
+    }
+}
+
+void HWC2On1Adapter::Layer::applySidebandState(hwc_layer_1_t& hwc1Layer) {
+    hwc1Layer.sidebandStream = mSidebandStream;
+}
+
+void HWC2On1Adapter::Layer::applyBufferState(hwc_layer_1_t& hwc1Layer) {
+    hwc1Layer.handle = mBuffer.getBuffer();
+    hwc1Layer.acquireFenceFd = mBuffer.getFence();
+}
+
+void HWC2On1Adapter::Layer::applyCompositionType(hwc_layer_1_t& hwc1Layer) {
+    // HWC1 never supports color transforms or dataspaces and only sometimes
+    // supports plane alpha (depending on the version). These require us to drop
+    // some or all layers to client composition.
+    if (mHasUnsupportedPlaneAlpha || mDisplay.hasColorTransform() ||
+            hasUnsupportedBackgroundColor()) {
+        hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+        hwc1Layer.flags = HWC_SKIP_LAYER;
+        return;
+    }
+
+    hwc1Layer.flags = 0;
+    switch (mCompositionType) {
+        case Composition::Client:
+            hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+            hwc1Layer.flags |= HWC_SKIP_LAYER;
+            break;
+        case Composition::Device:
+            hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+            break;
+        case Composition::SolidColor:
+            // In theory the following line should work, but since the HWC1
+            // version of SurfaceFlinger never used HWC_BACKGROUND, HWC1
+            // devices may not work correctly. To be on the safe side, we
+            // fall back to client composition.
+            //
+            // hwc1Layer.compositionType = HWC_BACKGROUND;
+            hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+            hwc1Layer.flags |= HWC_SKIP_LAYER;
+            break;
+        case Composition::Cursor:
+            hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+            if (mDisplay.getDevice().getHwc1MinorVersion() >= 4) {
+                hwc1Layer.hints |= HWC_IS_CURSOR_LAYER;
+            }
+            break;
+        case Composition::Sideband:
+            if (mDisplay.getDevice().getHwc1MinorVersion() < 4) {
+                hwc1Layer.compositionType = HWC_SIDEBAND;
+            } else {
+                hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+                hwc1Layer.flags |= HWC_SKIP_LAYER;
+            }
+            break;
+        default:
+            hwc1Layer.compositionType = HWC_FRAMEBUFFER;
+            hwc1Layer.flags |= HWC_SKIP_LAYER;
+            break;
+    }
+    ALOGV("Layer %" PRIu64 " %s set to %d", mId,
+            to_string(mCompositionType).c_str(),
+            hwc1Layer.compositionType);
+    ALOGV_IF(hwc1Layer.flags & HWC_SKIP_LAYER, "    and skipping");
+}
+
+// Adapter helpers
+
+void HWC2On1Adapter::populateCapabilities() {
+    if (mHwc1MinorVersion >= 3U) {
+        int supportedTypes = 0;
+        auto result = mHwc1Device->query(mHwc1Device,
+                HWC_DISPLAY_TYPES_SUPPORTED, &supportedTypes);
+        if ((result == 0) && ((supportedTypes & HWC_DISPLAY_VIRTUAL_BIT) != 0)) {
+            ALOGI("Found support for HWC virtual displays");
+            mHwc1SupportsVirtualDisplays = true;
+        }
+    }
+    if (mHwc1MinorVersion >= 4U) {
+        mCapabilities.insert(Capability::SidebandStream);
+    }
+
+    // Check for HWC background color layer support.
+    if (mHwc1MinorVersion >= 1U) {
+        int backgroundColorSupported = 0;
+        auto result = mHwc1Device->query(mHwc1Device,
+                                         HWC_BACKGROUND_LAYER_SUPPORTED,
+                                         &backgroundColorSupported);
+        if ((result == 0) && (backgroundColorSupported == 1)) {
+            ALOGV("Found support for HWC background color");
+            mHwc1SupportsBackgroundColor = true;
+        }
+    }
+
+    // Some devices might have HWC1 retire fences that accurately emulate
+    // HWC2 present fences when they are deferred, but it's not very reliable.
+    // To be safe, we indicate PresentFenceIsNotReliable for all HWC1 devices.
+    mCapabilities.insert(Capability::PresentFenceIsNotReliable);
+}
+
+HWC2On1Adapter::Display* HWC2On1Adapter::getDisplay(hwc2_display_t id) {
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    auto display = mDisplays.find(id);
+    if (display == mDisplays.end()) {
+        return nullptr;
+    }
+
+    return display->second.get();
+}
+
+std::tuple<HWC2On1Adapter::Layer*, Error> HWC2On1Adapter::getLayer(
+        hwc2_display_t displayId, hwc2_layer_t layerId) {
+    auto display = getDisplay(displayId);
+    if (!display) {
+        return std::make_tuple(static_cast<Layer*>(nullptr), Error::BadDisplay);
+    }
+
+    auto layerEntry = mLayers.find(layerId);
+    if (layerEntry == mLayers.end()) {
+        return std::make_tuple(static_cast<Layer*>(nullptr), Error::BadLayer);
+    }
+
+    auto layer = layerEntry->second;
+    if (layer->getDisplay().getId() != displayId) {
+        return std::make_tuple(static_cast<Layer*>(nullptr), Error::BadLayer);
+    }
+    return std::make_tuple(layer.get(), Error::None);
+}
+
+void HWC2On1Adapter::populatePrimary() {
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    auto display = std::make_shared<Display>(*this, HWC2::DisplayType::Physical);
+    mHwc1DisplayMap[HWC_DISPLAY_PRIMARY] = display->getId();
+    display->setHwc1Id(HWC_DISPLAY_PRIMARY);
+    display->populateConfigs();
+    mDisplays.emplace(display->getId(), std::move(display));
+}
+
+bool HWC2On1Adapter::prepareAllDisplays() {
+    ATRACE_CALL();
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    for (const auto& displayPair : mDisplays) {
+        auto& display = displayPair.second;
+        if (!display->prepare()) {
+            return false;
+        }
+    }
+
+    if (mHwc1DisplayMap.count(HWC_DISPLAY_PRIMARY) == 0) {
+        ALOGE("prepareAllDisplays: Unable to find primary HWC1 display");
+        return false;
+    }
+
+    // Build an array of hwc_display_contents_1 to call prepare() on HWC1.
+    mHwc1Contents.clear();
+
+    // Always push the primary display
+    auto primaryDisplayId = mHwc1DisplayMap[HWC_DISPLAY_PRIMARY];
+    auto& primaryDisplay = mDisplays[primaryDisplayId];
+    mHwc1Contents.push_back(primaryDisplay->getDisplayContents());
+
+    // Push the external display, if present
+    if (mHwc1DisplayMap.count(HWC_DISPLAY_EXTERNAL) != 0) {
+        auto externalDisplayId = mHwc1DisplayMap[HWC_DISPLAY_EXTERNAL];
+        auto& externalDisplay = mDisplays[externalDisplayId];
+        mHwc1Contents.push_back(externalDisplay->getDisplayContents());
+    } else {
+        // Even if an external display isn't present, we still need to send
+        // at least two displays down to HWC1
+        mHwc1Contents.push_back(nullptr);
+    }
+
+    // Push the hardware virtual display, if supported and present
+    if (mHwc1MinorVersion >= 3) {
+        if (mHwc1DisplayMap.count(HWC_DISPLAY_VIRTUAL) != 0) {
+            auto virtualDisplayId = mHwc1DisplayMap[HWC_DISPLAY_VIRTUAL];
+            auto& virtualDisplay = mDisplays[virtualDisplayId];
+            mHwc1Contents.push_back(virtualDisplay->getDisplayContents());
+        } else {
+            mHwc1Contents.push_back(nullptr);
+        }
+    }
+
+    for (auto& displayContents : mHwc1Contents) {
+        if (!displayContents) {
+            continue;
+        }
+
+        ALOGV("Display %zd layers:", mHwc1Contents.size() - 1);
+        for (size_t l = 0; l < displayContents->numHwLayers; ++l) {
+            auto& layer = displayContents->hwLayers[l];
+            ALOGV("  %zd: %d", l, layer.compositionType);
+        }
+    }
+
+    ALOGV("Calling HWC1 prepare");
+    {
+        ATRACE_NAME("HWC1 prepare");
+        mHwc1Device->prepare(mHwc1Device, mHwc1Contents.size(),
+                mHwc1Contents.data());
+    }
+
+    for (size_t c = 0; c < mHwc1Contents.size(); ++c) {
+        auto& contents = mHwc1Contents[c];
+        if (!contents) {
+            continue;
+        }
+        ALOGV("Display %zd layers:", c);
+        for (size_t l = 0; l < contents->numHwLayers; ++l) {
+            ALOGV("  %zd: %d", l, contents->hwLayers[l].compositionType);
+        }
+    }
+
+    // Return the received contents to their respective displays
+    for (size_t hwc1Id = 0; hwc1Id < mHwc1Contents.size(); ++hwc1Id) {
+        if (mHwc1Contents[hwc1Id] == nullptr) {
+            continue;
+        }
+
+        auto displayId = mHwc1DisplayMap[hwc1Id];
+        auto& display = mDisplays[displayId];
+        display->generateChanges();
+    }
+
+    return true;
+}
+
+void dumpHWC1Message(hwc_composer_device_1* device, size_t numDisplays,
+                     hwc_display_contents_1_t** displays) {
+    ALOGV("*****************************");
+    size_t displayId = 0;
+    while (displayId < numDisplays) {
+        hwc_display_contents_1_t* display = displays[displayId];
+
+        ALOGV("hwc_display_contents_1_t[%zu] @0x%p", displayId, display);
+        if (display == nullptr) {
+            displayId++;
+            continue;
+        }
+        ALOGV("  retirefd:0x%08x", display->retireFenceFd);
+        ALOGV("  outbuf  :0x%p", display->outbuf);
+        ALOGV("  outbuffd:0x%08x", display->outbufAcquireFenceFd);
+        ALOGV("  flags   :0x%08x", display->flags);
+        for(size_t layerId=0 ; layerId < display->numHwLayers ; layerId++) {
+            hwc_layer_1_t& layer = display->hwLayers[layerId];
+            ALOGV("    Layer[%zu]:", layerId);
+            ALOGV("      composition        : 0x%08x", layer.compositionType);
+            ALOGV("      hints              : 0x%08x", layer.hints);
+            ALOGV("      flags              : 0x%08x", layer.flags);
+            ALOGV("      handle             : 0x%p", layer.handle);
+            ALOGV("      transform          : 0x%08x", layer.transform);
+            ALOGV("      blending           : 0x%08x", layer.blending);
+            ALOGV("      sourceCropf        : %f, %f, %f, %f",
+                  layer.sourceCropf.left,
+                  layer.sourceCropf.top,
+                  layer.sourceCropf.right,
+                  layer.sourceCropf.bottom);
+            ALOGV("      displayFrame       : %d, %d, %d, %d",
+                  layer.displayFrame.left,
+                  layer.displayFrame.left,
+                  layer.displayFrame.left,
+                  layer.displayFrame.left);
+            hwc_region_t& visReg = layer.visibleRegionScreen;
+            ALOGV("      visibleRegionScreen: #0x%08zx[@0x%p]",
+                  visReg.numRects,
+                  visReg.rects);
+            for (size_t visRegId=0; visRegId < visReg.numRects ; visRegId++) {
+                if (layer.visibleRegionScreen.rects == nullptr) {
+                    ALOGV("        null");
+                } else {
+                    ALOGV("        visibleRegionScreen[%zu] %d, %d, %d, %d",
+                          visRegId,
+                          visReg.rects[visRegId].left,
+                          visReg.rects[visRegId].top,
+                          visReg.rects[visRegId].right,
+                          visReg.rects[visRegId].bottom);
+                }
+            }
+            ALOGV("      acquireFenceFd     : 0x%08x", layer.acquireFenceFd);
+            ALOGV("      releaseFenceFd     : 0x%08x", layer.releaseFenceFd);
+            ALOGV("      planeAlpha         : 0x%08x", layer.planeAlpha);
+            if (getMinorVersion(device) < 5)
+               continue;
+            ALOGV("      surfaceDamage      : #0x%08zx[@0x%p]",
+                  layer.surfaceDamage.numRects,
+                  layer.surfaceDamage.rects);
+            for (size_t sdId=0; sdId < layer.surfaceDamage.numRects ; sdId++) {
+                if (layer.surfaceDamage.rects == nullptr) {
+                    ALOGV("      null");
+                } else {
+                    ALOGV("      surfaceDamage[%zu] %d, %d, %d, %d",
+                          sdId,
+                          layer.surfaceDamage.rects[sdId].left,
+                          layer.surfaceDamage.rects[sdId].top,
+                          layer.surfaceDamage.rects[sdId].right,
+                          layer.surfaceDamage.rects[sdId].bottom);
+                }
+            }
+        }
+        displayId++;
+    }
+    ALOGV("-----------------------------");
+}
+
+Error HWC2On1Adapter::setAllDisplays() {
+    ATRACE_CALL();
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    // Make sure we're ready to validate
+    for (size_t hwc1Id = 0; hwc1Id < mHwc1Contents.size(); ++hwc1Id) {
+        if (mHwc1Contents[hwc1Id] == nullptr) {
+            continue;
+        }
+
+        auto displayId = mHwc1DisplayMap[hwc1Id];
+        auto& display = mDisplays[displayId];
+        Error error = display->set(*mHwc1Contents[hwc1Id]);
+        if (error != Error::None) {
+            ALOGE("setAllDisplays: Failed to set display %zd: %s", hwc1Id,
+                    to_string(error).c_str());
+            return error;
+        }
+    }
+
+    ALOGV("Calling HWC1 set");
+    {
+        ATRACE_NAME("HWC1 set");
+        //dumpHWC1Message(mHwc1Device, mHwc1Contents.size(), mHwc1Contents.data());
+        mHwc1Device->set(mHwc1Device, mHwc1Contents.size(),
+                mHwc1Contents.data());
+    }
+
+    // Add retire and release fences
+    for (size_t hwc1Id = 0; hwc1Id < mHwc1Contents.size(); ++hwc1Id) {
+        if (mHwc1Contents[hwc1Id] == nullptr) {
+            continue;
+        }
+
+        auto displayId = mHwc1DisplayMap[hwc1Id];
+        auto& display = mDisplays[displayId];
+        auto retireFenceFd = mHwc1Contents[hwc1Id]->retireFenceFd;
+        ALOGV("setAllDisplays: Adding retire fence %d to display %zd",
+                retireFenceFd, hwc1Id);
+        display->addRetireFence(mHwc1Contents[hwc1Id]->retireFenceFd);
+        display->addReleaseFences(*mHwc1Contents[hwc1Id]);
+    }
+
+    return Error::None;
+}
+
+void HWC2On1Adapter::hwc1Invalidate() {
+    ALOGV("Received hwc1Invalidate");
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    // If the HWC2-side callback hasn't been registered yet, buffer this until
+    // it is registered.
+    if (mCallbacks.count(Callback::Refresh) == 0) {
+        mHasPendingInvalidate = true;
+        return;
+    }
+
+    const auto& callbackInfo = mCallbacks[Callback::Refresh];
+    std::vector<hwc2_display_t> displays;
+    for (const auto& displayPair : mDisplays) {
+        displays.emplace_back(displayPair.first);
+    }
+
+    // Call back without the state lock held.
+    lock.unlock();
+
+    auto refresh = reinterpret_cast<HWC2_PFN_REFRESH>(callbackInfo.pointer);
+    for (auto display : displays) {
+        refresh(callbackInfo.data, display);
+    }
+}
+
+void HWC2On1Adapter::hwc1Vsync(int hwc1DisplayId, int64_t timestamp) {
+    ALOGV("Received hwc1Vsync(%d, %" PRId64 ")", hwc1DisplayId, timestamp);
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    // If the HWC2-side callback hasn't been registered yet, buffer this until
+    // it is registered.
+    if (mCallbacks.count(Callback::Vsync) == 0) {
+        mPendingVsyncs.emplace_back(hwc1DisplayId, timestamp);
+        return;
+    }
+
+    if (mHwc1DisplayMap.count(hwc1DisplayId) == 0) {
+        ALOGE("hwc1Vsync: Couldn't find display for HWC1 id %d", hwc1DisplayId);
+        return;
+    }
+
+    const auto& callbackInfo = mCallbacks[Callback::Vsync];
+    auto displayId = mHwc1DisplayMap[hwc1DisplayId];
+
+    // Call back without the state lock held.
+    lock.unlock();
+
+    auto vsync = reinterpret_cast<HWC2_PFN_VSYNC>(callbackInfo.pointer);
+    vsync(callbackInfo.data, displayId, timestamp);
+}
+
+void HWC2On1Adapter::hwc1Hotplug(int hwc1DisplayId, int connected) {
+    ALOGV("Received hwc1Hotplug(%d, %d)", hwc1DisplayId, connected);
+
+    if (hwc1DisplayId != HWC_DISPLAY_EXTERNAL) {
+        ALOGE("hwc1Hotplug: Received hotplug for non-external display");
+        return;
+    }
+
+    std::unique_lock<std::recursive_timed_mutex> lock(mStateMutex);
+
+    // If the HWC2-side callback hasn't been registered yet, buffer this until
+    // it is registered
+    if (mCallbacks.count(Callback::Hotplug) == 0) {
+        mPendingHotplugs.emplace_back(hwc1DisplayId, connected);
+        return;
+    }
+
+    hwc2_display_t displayId = UINT64_MAX;
+    if (mHwc1DisplayMap.count(hwc1DisplayId) == 0) {
+        if (connected == 0) {
+            ALOGW("hwc1Hotplug: Received disconnect for unconnected display");
+            return;
+        }
+
+        // Create a new display on connect
+        auto display = std::make_shared<HWC2On1Adapter::Display>(*this,
+                HWC2::DisplayType::Physical);
+        display->setHwc1Id(HWC_DISPLAY_EXTERNAL);
+        display->populateConfigs();
+        displayId = display->getId();
+        mHwc1DisplayMap[HWC_DISPLAY_EXTERNAL] = displayId;
+        mDisplays.emplace(displayId, std::move(display));
+    } else {
+        if (connected != 0) {
+            ALOGW("hwc1Hotplug: Received connect for previously connected "
+                    "display");
+            return;
+        }
+
+        // Disconnect an existing display
+        displayId = mHwc1DisplayMap[hwc1DisplayId];
+        mHwc1DisplayMap.erase(HWC_DISPLAY_EXTERNAL);
+        mDisplays.erase(displayId);
+    }
+
+    const auto& callbackInfo = mCallbacks[Callback::Hotplug];
+
+    // Call back without the state lock held
+    lock.unlock();
+
+    auto hotplug = reinterpret_cast<HWC2_PFN_HOTPLUG>(callbackInfo.pointer);
+    auto hwc2Connected = (connected == 0) ?
+            HWC2::Connection::Disconnected : HWC2::Connection::Connected;
+    hotplug(callbackInfo.data, displayId, static_cast<int32_t>(hwc2Connected));
+}
+} // namespace android
diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/MiniFence.cpp b/graphics/composer/2.1/utils/hwc2on1adapter/MiniFence.cpp
new file mode 100644
index 0000000..dfbe4d6
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/MiniFence.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2017 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 "hwc2on1adapter/MiniFence.h"
+
+#include <unistd.h>
+
+namespace android {
+
+const sp<MiniFence> MiniFence::NO_FENCE = sp<MiniFence>(new MiniFence);
+
+MiniFence::MiniFence() :
+    mFenceFd(-1) {
+}
+
+MiniFence::MiniFence(int fenceFd) :
+    mFenceFd(fenceFd) {
+}
+
+MiniFence::~MiniFence() {
+    if (mFenceFd != -1) {
+        close(mFenceFd);
+    }
+}
+
+int MiniFence::dup() const {
+    return ::dup(mFenceFd);
+}
+}
diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/HWC2On1Adapter.h b/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/HWC2On1Adapter.h
new file mode 100644
index 0000000..3badfce
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/HWC2On1Adapter.h
@@ -0,0 +1,738 @@
+/*
+ * Copyright 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SF_HWC2_ON_1_ADAPTER_H
+#define ANDROID_SF_HWC2_ON_1_ADAPTER_H
+
+#define HWC2_INCLUDE_STRINGIFICATION
+#define HWC2_USE_CPP11
+#include <hardware/hwcomposer2.h>
+#undef HWC2_INCLUDE_STRINGIFICATION
+#undef HWC2_USE_CPP11
+
+#include "MiniFence.h"
+
+#include <atomic>
+#include <map>
+#include <mutex>
+#include <queue>
+#include <set>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+
+struct hwc_composer_device_1;
+struct hwc_display_contents_1;
+struct hwc_layer_1;
+
+namespace android {
+
+// For devices unable to provide an implementation of HWC2 (see hwcomposer2.h),
+// we provide an adapter able to talk to HWC1 (see hwcomposer.h). It translates
+// streamed function calls ala HWC2 model to batched array of structs calls ala
+// HWC1 model.
+class HWC2On1Adapter : public hwc2_device_t
+{
+public:
+    explicit HWC2On1Adapter(struct hwc_composer_device_1* hwc1Device);
+    ~HWC2On1Adapter();
+
+    struct hwc_composer_device_1* getHwc1Device() const { return mHwc1Device; }
+    uint8_t getHwc1MinorVersion() const { return mHwc1MinorVersion; }
+
+private:
+    static inline HWC2On1Adapter* getAdapter(hwc2_device_t* device) {
+        return static_cast<HWC2On1Adapter*>(device);
+    }
+
+    // getCapabilities
+
+    void doGetCapabilities(uint32_t* outCount,
+            int32_t* /*hwc2_capability_t*/ outCapabilities);
+    static void getCapabilitiesHook(hwc2_device_t* device, uint32_t* outCount,
+            int32_t* /*hwc2_capability_t*/ outCapabilities) {
+        getAdapter(device)->doGetCapabilities(outCount, outCapabilities);
+    }
+
+    bool supportsBackgroundColor() {
+        return mHwc1SupportsBackgroundColor;
+    }
+
+    // getFunction
+
+    hwc2_function_pointer_t doGetFunction(HWC2::FunctionDescriptor descriptor);
+    static hwc2_function_pointer_t getFunctionHook(hwc2_device_t* device,
+            int32_t intDesc) {
+        auto descriptor = static_cast<HWC2::FunctionDescriptor>(intDesc);
+        return getAdapter(device)->doGetFunction(descriptor);
+    }
+
+    // Device functions
+
+    HWC2::Error createVirtualDisplay(uint32_t width, uint32_t height,
+            hwc2_display_t* outDisplay);
+    static int32_t createVirtualDisplayHook(hwc2_device_t* device,
+            uint32_t width, uint32_t height, int32_t* /*format*/,
+            hwc2_display_t* outDisplay) {
+        // HWC1 implementations cannot override the buffer format requested by
+        // the consumer
+        auto error = getAdapter(device)->createVirtualDisplay(width, height,
+                outDisplay);
+        return static_cast<int32_t>(error);
+    }
+
+    HWC2::Error destroyVirtualDisplay(hwc2_display_t display);
+    static int32_t destroyVirtualDisplayHook(hwc2_device_t* device,
+            hwc2_display_t display) {
+        auto error = getAdapter(device)->destroyVirtualDisplay(display);
+        return static_cast<int32_t>(error);
+    }
+
+    std::string mDumpString;
+    void dump(uint32_t* outSize, char* outBuffer);
+    static void dumpHook(hwc2_device_t* device, uint32_t* outSize,
+            char* outBuffer) {
+        getAdapter(device)->dump(outSize, outBuffer);
+    }
+
+    uint32_t getMaxVirtualDisplayCount();
+    static uint32_t getMaxVirtualDisplayCountHook(hwc2_device_t* device) {
+        return getAdapter(device)->getMaxVirtualDisplayCount();
+    }
+
+    HWC2::Error registerCallback(HWC2::Callback descriptor,
+            hwc2_callback_data_t callbackData, hwc2_function_pointer_t pointer);
+    static int32_t registerCallbackHook(hwc2_device_t* device,
+            int32_t intDesc, hwc2_callback_data_t callbackData,
+            hwc2_function_pointer_t pointer) {
+        auto descriptor = static_cast<HWC2::Callback>(intDesc);
+        auto error = getAdapter(device)->registerCallback(descriptor,
+                callbackData, pointer);
+        return static_cast<int32_t>(error);
+    }
+
+    // Display functions
+
+    class Layer;
+
+    class SortLayersByZ {
+        public:
+            bool operator()(const std::shared_ptr<Layer>& lhs,
+                    const std::shared_ptr<Layer>& rhs);
+    };
+
+    // The semantics of the fences returned by the device differ between
+    // hwc1.set() and hwc2.present(). Read hwcomposer.h and hwcomposer2.h
+    // for more information.
+    //
+    // Release fences in hwc1 are obtained on set() for a frame n and signaled
+    // when the layer buffer is not needed for read operations anymore
+    // (typically on frame n+1). In HWC2, release fences are obtained with a
+    // special call after present() for frame n. These fences signal
+    // on frame n: More specifically, the fence for a given buffer provided in
+    // frame n will signal when the prior buffer is no longer required.
+    //
+    // A retire fence (HWC1) is signaled when a composition is replaced
+    // on the panel whereas a present fence (HWC2) is signaled when a
+    // composition starts to be displayed on a panel.
+    //
+    // The HWC2to1Adapter emulates the new fence semantics for a frame
+    // n by returning the fence from frame n-1. For frame 0, the adapter
+    // returns NO_FENCE.
+    class DeferredFence {
+        public:
+            DeferredFence()
+              : mFences({MiniFence::NO_FENCE, MiniFence::NO_FENCE}) {}
+
+            void add(int32_t fenceFd) {
+                mFences.emplace(new MiniFence(fenceFd));
+                mFences.pop();
+            }
+
+            const sp<MiniFence>& get() const {
+                return mFences.front();
+            }
+
+        private:
+            // There are always two fences in this queue.
+            std::queue<sp<MiniFence>> mFences;
+    };
+
+    class FencedBuffer {
+        public:
+            FencedBuffer() : mBuffer(nullptr), mFence(MiniFence::NO_FENCE) {}
+
+            void setBuffer(buffer_handle_t buffer) { mBuffer = buffer; }
+            void setFence(int fenceFd) { mFence = new MiniFence(fenceFd); }
+
+            buffer_handle_t getBuffer() const { return mBuffer; }
+            int getFence() const { return mFence->dup(); }
+
+        private:
+            buffer_handle_t mBuffer;
+            sp<MiniFence> mFence;
+    };
+
+    class Display {
+        public:
+            Display(HWC2On1Adapter& device, HWC2::DisplayType type);
+
+            hwc2_display_t getId() const { return mId; }
+            HWC2On1Adapter& getDevice() const { return mDevice; }
+
+            // Does not require locking because it is set before adding the
+            // Displays to the Adapter's list of displays
+            void setHwc1Id(int32_t id) { mHwc1Id = id; }
+            int32_t getHwc1Id() const { return mHwc1Id; }
+
+            // HWC2 Display functions
+            HWC2::Error acceptChanges();
+            HWC2::Error createLayer(hwc2_layer_t* outLayerId);
+            HWC2::Error destroyLayer(hwc2_layer_t layerId);
+            HWC2::Error getActiveConfig(hwc2_config_t* outConfigId);
+            HWC2::Error getAttribute(hwc2_config_t configId,
+                    HWC2::Attribute attribute, int32_t* outValue);
+            HWC2::Error getChangedCompositionTypes(uint32_t* outNumElements,
+                    hwc2_layer_t* outLayers, int32_t* outTypes);
+            HWC2::Error getColorModes(uint32_t* outNumModes, int32_t* outModes);
+            HWC2::Error getConfigs(uint32_t* outNumConfigs,
+                    hwc2_config_t* outConfigIds);
+            HWC2::Error getDozeSupport(int32_t* outSupport);
+            HWC2::Error getHdrCapabilities(uint32_t* outNumTypes,
+                    int32_t* outTypes, float* outMaxLuminance,
+                    float* outMaxAverageLuminance, float* outMinLuminance);
+            HWC2::Error getName(uint32_t* outSize, char* outName);
+            HWC2::Error getReleaseFences(uint32_t* outNumElements,
+                    hwc2_layer_t* outLayers, int32_t* outFences);
+            HWC2::Error getRequests(int32_t* outDisplayRequests,
+                    uint32_t* outNumElements, hwc2_layer_t* outLayers,
+                    int32_t* outLayerRequests);
+            HWC2::Error getType(int32_t* outType);
+
+            // Since HWC1 "presents" (called "set" in HWC1) all Displays
+            // at once, the first call to any Display::present will trigger
+            // present() on all Displays in the Device. Subsequent calls without
+            // first calling validate() are noop (except for duping/returning
+            // the retire fence).
+            HWC2::Error present(int32_t* outRetireFence);
+
+            HWC2::Error setActiveConfig(hwc2_config_t configId);
+            HWC2::Error setClientTarget(buffer_handle_t target,
+                    int32_t acquireFence, int32_t dataspace,
+                    hwc_region_t damage);
+            HWC2::Error setColorMode(android_color_mode_t mode);
+            HWC2::Error setColorTransform(android_color_transform_t hint);
+            HWC2::Error setOutputBuffer(buffer_handle_t buffer,
+                    int32_t releaseFence);
+            HWC2::Error setPowerMode(HWC2::PowerMode mode);
+            HWC2::Error setVsyncEnabled(HWC2::Vsync enabled);
+
+            // Since HWC1 "validates" (called "prepare" in HWC1) all Displays
+            // at once, the first call to any Display::validate() will trigger
+            // validate() on all other Displays in the Device.
+            HWC2::Error validate(uint32_t* outNumTypes,
+                    uint32_t* outNumRequests);
+
+            HWC2::Error updateLayerZ(hwc2_layer_t layerId, uint32_t z);
+
+            HWC2::Error getClientTargetSupport(uint32_t width, uint32_t height,
+                     int32_t format, int32_t dataspace);
+
+            // Read configs from HWC1 device
+            void populateConfigs();
+
+            // Set configs for a virtual display
+            void populateConfigs(uint32_t width, uint32_t height);
+
+            bool prepare();
+
+            // Called after hwc.prepare() with responses from the device.
+            void generateChanges();
+
+            bool hasChanges() const;
+            HWC2::Error set(hwc_display_contents_1& hwcContents);
+            void addRetireFence(int fenceFd);
+            void addReleaseFences(const hwc_display_contents_1& hwcContents);
+
+            bool hasColorTransform() const;
+
+            std::string dump() const;
+
+            // Return a rect from the pool allocated during validate()
+            hwc_rect_t* GetRects(size_t numRects);
+
+            hwc_display_contents_1* getDisplayContents();
+
+            void markGeometryChanged() { mGeometryChanged = true; }
+            void resetGeometryMarker() { mGeometryChanged = false;}
+        private:
+            class Config {
+                public:
+                    Config(Display& display)
+                      : mDisplay(display),
+                        mId(0),
+                        mAttributes() {}
+
+                    bool isOnDisplay(const Display& display) const {
+                        return display.getId() == mDisplay.getId();
+                    }
+
+                    void setAttribute(HWC2::Attribute attribute, int32_t value);
+                    int32_t getAttribute(HWC2::Attribute attribute) const;
+
+                    void setHwc1Id(uint32_t id);
+                    bool hasHwc1Id(uint32_t id) const;
+                    HWC2::Error getColorModeForHwc1Id(uint32_t id,
+                            android_color_mode_t *outMode) const;
+                    HWC2::Error getHwc1IdForColorMode(android_color_mode_t mode,
+                            uint32_t* outId) const;
+
+                    void setId(hwc2_config_t id) { mId = id; }
+                    hwc2_config_t getId() const { return mId; }
+
+                    // Attempts to merge two configs that differ only in color
+                    // mode. Returns whether the merge was successful
+                    bool merge(const Config& other);
+
+                    std::set<android_color_mode_t> getColorModes() const;
+
+                    // splitLine divides the output into two lines suitable for
+                    // dumpsys SurfaceFlinger
+                    std::string toString(bool splitLine = false) const;
+
+                private:
+                    Display& mDisplay;
+                    hwc2_config_t mId;
+                    std::unordered_map<HWC2::Attribute, int32_t> mAttributes;
+
+                    // Maps from color transform to HWC1 config ID
+                    std::unordered_map<android_color_mode_t, uint32_t> mHwc1Ids;
+            };
+
+            // Stores changes requested from the device upon calling prepare().
+            // Handles change request to:
+            //   - Layer composition type.
+            //   - Layer hints.
+            class Changes {
+                public:
+                    uint32_t getNumTypes() const {
+                        return static_cast<uint32_t>(mTypeChanges.size());
+                    }
+
+                    uint32_t getNumLayerRequests() const {
+                        return static_cast<uint32_t>(mLayerRequests.size());
+                    }
+
+                    const std::unordered_map<hwc2_layer_t, HWC2::Composition>&
+                            getTypeChanges() const {
+                        return mTypeChanges;
+                    }
+
+                    const std::unordered_map<hwc2_layer_t, HWC2::LayerRequest>&
+                            getLayerRequests() const {
+                        return mLayerRequests;
+                    }
+
+                    void addTypeChange(hwc2_layer_t layerId,
+                            HWC2::Composition type) {
+                        mTypeChanges.insert({layerId, type});
+                    }
+
+                    void clearTypeChanges() { mTypeChanges.clear(); }
+
+                    void addLayerRequest(hwc2_layer_t layerId,
+                            HWC2::LayerRequest request) {
+                        mLayerRequests.insert({layerId, request});
+                    }
+
+                private:
+                    std::unordered_map<hwc2_layer_t, HWC2::Composition>
+                            mTypeChanges;
+                    std::unordered_map<hwc2_layer_t, HWC2::LayerRequest>
+                            mLayerRequests;
+            };
+
+            std::shared_ptr<const Config>
+                    getConfig(hwc2_config_t configId) const;
+
+            void populateColorModes();
+            void initializeActiveConfig();
+
+            // Creates a bi-directional mapping between index in HWC1
+            // prepare/set array and Layer object. Stores mapping in
+            // mHwc1LayerMap and also updates Layer's attribute mHwc1Id.
+            void assignHwc1LayerIds();
+
+            // Called after a response to prepare() has been received:
+            // Ingest composition type changes requested by the device.
+            void updateTypeChanges(const struct hwc_layer_1& hwc1Layer,
+                    const Layer& layer);
+
+            // Called after a response to prepare() has been received:
+            // Ingest layer hint changes requested by the device.
+            void updateLayerRequests(const struct hwc_layer_1& hwc1Layer,
+                    const Layer& layer);
+
+            // Set all fields in HWC1 comm array for layer containing the
+            // HWC_FRAMEBUFFER_TARGET (always the last layer).
+            void prepareFramebufferTarget();
+
+            // Display ID generator.
+            static std::atomic<hwc2_display_t> sNextId;
+            const hwc2_display_t mId;
+
+
+            HWC2On1Adapter& mDevice;
+
+            // The state of this display should only be modified from
+            // SurfaceFlinger's main loop, with the exception of when dump is
+            // called. To prevent a bad state from crashing us during a dump
+            // call, all public calls into Display must acquire this mutex.
+            //
+            // It is recursive because we don't want to deadlock in validate
+            // (or present) when we call HWC2On1Adapter::prepareAllDisplays
+            // (or setAllDisplays), which calls back into Display functions
+            // which require locking.
+            mutable std::recursive_mutex mStateMutex;
+
+            // Allocate RAM able to store all layers and rects used for
+            // communication with HWC1. Place allocated RAM in variable
+            // mHwc1RequestedContents.
+            void allocateRequestedContents();
+
+            // Array of structs exchanged between client and hwc1 device.
+            // Sent to device upon calling prepare().
+            std::unique_ptr<hwc_display_contents_1> mHwc1RequestedContents;
+    private:
+            DeferredFence mRetireFence;
+
+            // Will only be non-null after the Display has been validated and
+            // before it has been presented
+            std::unique_ptr<Changes> mChanges;
+
+            int32_t mHwc1Id;
+
+            std::vector<std::shared_ptr<Config>> mConfigs;
+            std::shared_ptr<const Config> mActiveConfig;
+            std::set<android_color_mode_t> mColorModes;
+            android_color_mode_t mActiveColorMode;
+            std::string mName;
+            HWC2::DisplayType mType;
+            HWC2::PowerMode mPowerMode;
+            HWC2::Vsync mVsyncEnabled;
+
+            // Used to populate HWC1 HWC_FRAMEBUFFER_TARGET layer
+            FencedBuffer mClientTarget;
+
+
+            FencedBuffer mOutputBuffer;
+
+            bool mHasColorTransform;
+
+            // All layers this Display is aware of.
+            std::multiset<std::shared_ptr<Layer>, SortLayersByZ> mLayers;
+
+            // Mapping between layer index in array of hwc_display_contents_1*
+            // passed to HWC1 during validate/set and Layer object.
+            std::unordered_map<size_t, std::shared_ptr<Layer>> mHwc1LayerMap;
+
+            // All communication with HWC1 via prepare/set is done with one
+            // alloc. This pointer is pointing to a pool of hwc_rect_t.
+            size_t mNumAvailableRects;
+            hwc_rect_t* mNextAvailableRect;
+
+            // True if any of the Layers contained in this Display have been
+            // updated with anything other than a buffer since last call to
+            // Display::set()
+            bool mGeometryChanged;
+    };
+
+    // Utility template calling a Display object method directly based on the
+    // hwc2_display_t displayId parameter.
+    template <typename ...Args>
+    static int32_t callDisplayFunction(hwc2_device_t* device,
+            hwc2_display_t displayId, HWC2::Error (Display::*member)(Args...),
+            Args... args) {
+        auto display = getAdapter(device)->getDisplay(displayId);
+        if (!display) {
+            return static_cast<int32_t>(HWC2::Error::BadDisplay);
+        }
+        auto error = ((*display).*member)(std::forward<Args>(args)...);
+        return static_cast<int32_t>(error);
+    }
+
+    template <typename MF, MF memFunc, typename ...Args>
+    static int32_t displayHook(hwc2_device_t* device, hwc2_display_t displayId,
+            Args... args) {
+        return HWC2On1Adapter::callDisplayFunction(device, displayId, memFunc,
+                std::forward<Args>(args)...);
+    }
+
+    static int32_t getDisplayAttributeHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_config_t config,
+            int32_t intAttribute, int32_t* outValue) {
+        auto attribute = static_cast<HWC2::Attribute>(intAttribute);
+        return callDisplayFunction(device, display, &Display::getAttribute,
+                config, attribute, outValue);
+    }
+
+    static int32_t setColorTransformHook(hwc2_device_t* device,
+            hwc2_display_t display, const float* /*matrix*/,
+            int32_t /*android_color_transform_t*/ intHint) {
+        // We intentionally throw away the matrix, because if the hint is
+        // anything other than IDENTITY, we have to fall back to client
+        // composition anyway
+        auto hint = static_cast<android_color_transform_t>(intHint);
+        return callDisplayFunction(device, display, &Display::setColorTransform,
+                hint);
+    }
+
+    static int32_t setColorModeHook(hwc2_device_t* device,
+            hwc2_display_t display, int32_t /*android_color_mode_t*/ intMode) {
+        auto mode = static_cast<android_color_mode_t>(intMode);
+        return callDisplayFunction(device, display, &Display::setColorMode,
+                mode);
+    }
+
+    static int32_t setPowerModeHook(hwc2_device_t* device,
+            hwc2_display_t display, int32_t intMode) {
+        auto mode = static_cast<HWC2::PowerMode>(intMode);
+        return callDisplayFunction(device, display, &Display::setPowerMode,
+                mode);
+    }
+
+    static int32_t setVsyncEnabledHook(hwc2_device_t* device,
+            hwc2_display_t display, int32_t intEnabled) {
+        auto enabled = static_cast<HWC2::Vsync>(intEnabled);
+        return callDisplayFunction(device, display, &Display::setVsyncEnabled,
+                enabled);
+    }
+
+    class Layer {
+        public:
+            explicit Layer(Display& display);
+
+            bool operator==(const Layer& other) { return mId == other.mId; }
+            bool operator!=(const Layer& other) { return !(*this == other); }
+
+            hwc2_layer_t getId() const { return mId; }
+            Display& getDisplay() const { return mDisplay; }
+
+            // HWC2 Layer functions
+            HWC2::Error setBuffer(buffer_handle_t buffer, int32_t acquireFence);
+            HWC2::Error setCursorPosition(int32_t x, int32_t y);
+            HWC2::Error setSurfaceDamage(hwc_region_t damage);
+
+            // HWC2 Layer state functions
+            HWC2::Error setBlendMode(HWC2::BlendMode mode);
+            HWC2::Error setColor(hwc_color_t color);
+            HWC2::Error setCompositionType(HWC2::Composition type);
+            HWC2::Error setDataspace(android_dataspace_t dataspace);
+            HWC2::Error setDisplayFrame(hwc_rect_t frame);
+            HWC2::Error setPlaneAlpha(float alpha);
+            HWC2::Error setSidebandStream(const native_handle_t* stream);
+            HWC2::Error setSourceCrop(hwc_frect_t crop);
+            HWC2::Error setTransform(HWC2::Transform transform);
+            HWC2::Error setVisibleRegion(hwc_region_t visible);
+            HWC2::Error setZ(uint32_t z);
+
+            HWC2::Composition getCompositionType() const {
+                return mCompositionType;
+            }
+            uint32_t getZ() const { return mZ; }
+
+            void addReleaseFence(int fenceFd);
+            const sp<MiniFence>& getReleaseFence() const;
+
+            void setHwc1Id(size_t id) { mHwc1Id = id; }
+            size_t getHwc1Id() const { return mHwc1Id; }
+
+            // Write state to HWC1 communication struct.
+            void applyState(struct hwc_layer_1& hwc1Layer);
+
+            std::string dump() const;
+
+            std::size_t getNumVisibleRegions() { return mVisibleRegion.size(); }
+
+            std::size_t getNumSurfaceDamages() { return mSurfaceDamage.size(); }
+
+            // True if a layer cannot be properly rendered by the device due
+            // to usage of SolidColor (a.k.a BackgroundColor in HWC1).
+            bool hasUnsupportedBackgroundColor() {
+                return (mCompositionType == HWC2::Composition::SolidColor &&
+                        !mDisplay.getDevice().supportsBackgroundColor());
+            }
+        private:
+            void applyCommonState(struct hwc_layer_1& hwc1Layer);
+            void applySolidColorState(struct hwc_layer_1& hwc1Layer);
+            void applySidebandState(struct hwc_layer_1& hwc1Layer);
+            void applyBufferState(struct hwc_layer_1& hwc1Layer);
+            void applyCompositionType(struct hwc_layer_1& hwc1Layer);
+
+            static std::atomic<hwc2_layer_t> sNextId;
+            const hwc2_layer_t mId;
+            Display& mDisplay;
+
+            FencedBuffer mBuffer;
+            std::vector<hwc_rect_t> mSurfaceDamage;
+
+            HWC2::BlendMode mBlendMode;
+            hwc_color_t mColor;
+            HWC2::Composition mCompositionType;
+            hwc_rect_t mDisplayFrame;
+            float mPlaneAlpha;
+            const native_handle_t* mSidebandStream;
+            hwc_frect_t mSourceCrop;
+            HWC2::Transform mTransform;
+            std::vector<hwc_rect_t> mVisibleRegion;
+
+            uint32_t mZ;
+
+            DeferredFence mReleaseFence;
+
+            size_t mHwc1Id;
+            bool mHasUnsupportedPlaneAlpha;
+    };
+
+    // Utility tempate calling a Layer object method based on ID parameters:
+    // hwc2_display_t displayId
+    // and
+    // hwc2_layer_t layerId
+    template <typename ...Args>
+    static int32_t callLayerFunction(hwc2_device_t* device,
+            hwc2_display_t displayId, hwc2_layer_t layerId,
+            HWC2::Error (Layer::*member)(Args...), Args... args) {
+        auto result = getAdapter(device)->getLayer(displayId, layerId);
+        auto error = std::get<HWC2::Error>(result);
+        if (error == HWC2::Error::None) {
+            auto layer = std::get<Layer*>(result);
+            error = ((*layer).*member)(std::forward<Args>(args)...);
+        }
+        return static_cast<int32_t>(error);
+    }
+
+    template <typename MF, MF memFunc, typename ...Args>
+    static int32_t layerHook(hwc2_device_t* device, hwc2_display_t displayId,
+            hwc2_layer_t layerId, Args... args) {
+        return HWC2On1Adapter::callLayerFunction(device, displayId, layerId,
+                memFunc, std::forward<Args>(args)...);
+    }
+
+    // Layer state functions
+
+    static int32_t setLayerBlendModeHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_layer_t layer, int32_t intMode) {
+        auto mode = static_cast<HWC2::BlendMode>(intMode);
+        return callLayerFunction(device, display, layer,
+                &Layer::setBlendMode, mode);
+    }
+
+    static int32_t setLayerCompositionTypeHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_layer_t layer, int32_t intType) {
+        auto type = static_cast<HWC2::Composition>(intType);
+        return callLayerFunction(device, display, layer,
+                &Layer::setCompositionType, type);
+    }
+
+    static int32_t setLayerDataspaceHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_layer_t layer, int32_t intDataspace) {
+        auto dataspace = static_cast<android_dataspace_t>(intDataspace);
+        return callLayerFunction(device, display, layer, &Layer::setDataspace,
+                dataspace);
+    }
+
+    static int32_t setLayerTransformHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_layer_t layer, int32_t intTransform) {
+        auto transform = static_cast<HWC2::Transform>(intTransform);
+        return callLayerFunction(device, display, layer, &Layer::setTransform,
+                transform);
+    }
+
+    static int32_t setLayerZOrderHook(hwc2_device_t* device,
+            hwc2_display_t display, hwc2_layer_t layer, uint32_t z) {
+        return callDisplayFunction(device, display, &Display::updateLayerZ,
+                layer, z);
+    }
+
+    // Adapter internals
+
+    void populateCapabilities();
+    Display* getDisplay(hwc2_display_t id);
+    std::tuple<Layer*, HWC2::Error> getLayer(hwc2_display_t displayId,
+            hwc2_layer_t layerId);
+    void populatePrimary();
+
+    bool prepareAllDisplays();
+    std::vector<struct hwc_display_contents_1*> mHwc1Contents;
+    HWC2::Error setAllDisplays();
+
+    // Callbacks
+    void hwc1Invalidate();
+    void hwc1Vsync(int hwc1DisplayId, int64_t timestamp);
+    void hwc1Hotplug(int hwc1DisplayId, int connected);
+
+    // These are set in the constructor and before any asynchronous events are
+    // possible
+
+    struct hwc_composer_device_1* const mHwc1Device;
+    const uint8_t mHwc1MinorVersion;
+    bool mHwc1SupportsVirtualDisplays;
+    bool mHwc1SupportsBackgroundColor;
+
+    class Callbacks;
+    const std::unique_ptr<Callbacks> mHwc1Callbacks;
+
+    std::unordered_set<HWC2::Capability> mCapabilities;
+
+    // These are only accessed from the main SurfaceFlinger thread (not from
+    // callbacks or dump
+
+    std::map<hwc2_layer_t, std::shared_ptr<Layer>> mLayers;
+
+    // A HWC1 supports only one virtual display.
+    std::shared_ptr<Display> mHwc1VirtualDisplay;
+
+    // These are potentially accessed from multiple threads, and are protected
+    // by this mutex. This needs to be recursive, since the HWC1 implementation
+    // can call back into the invalidate callback on the same thread that is
+    // calling prepare.
+    std::recursive_timed_mutex mStateMutex;
+
+    struct CallbackInfo {
+        hwc2_callback_data_t data;
+        hwc2_function_pointer_t pointer;
+    };
+    std::unordered_map<HWC2::Callback, CallbackInfo> mCallbacks;
+    bool mHasPendingInvalidate;
+
+    // There is a small gap between the time the HWC1 module is started and
+    // when the callbacks for vsync and hotplugs are registered by the
+    // HWC2on1Adapter. To prevent losing events they are stored in these arrays
+    // and fed to the callback as soon as possible.
+    std::vector<std::pair<int, int64_t>> mPendingVsyncs;
+    std::vector<std::pair<int, int>> mPendingHotplugs;
+
+    // Mapping between HWC1 display id and Display objects.
+    std::map<hwc2_display_t, std::shared_ptr<Display>> mDisplays;
+
+    // Map HWC1 display type (HWC_DISPLAY_PRIMARY, HWC_DISPLAY_EXTERNAL,
+    // HWC_DISPLAY_VIRTUAL) to Display IDs generated by HWC2on1Adapter objects.
+    std::unordered_map<int, hwc2_display_t> mHwc1DisplayMap;
+};
+
+} // namespace android
+
+#endif
diff --git a/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/MiniFence.h b/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/MiniFence.h
new file mode 100644
index 0000000..75de764
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2on1adapter/include/hwc2on1adapter/MiniFence.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MINIFENCE_H
+#define MINIFENCE_H
+
+#include <utils/RefBase.h>
+
+namespace android {
+
+/* MiniFence is a minimal re-implementation of Fence from libui. It exists to
+ * avoid linking the HWC2on1Adapter to libui and satisfy Treble requirements.
+ */
+class MiniFence : public LightRefBase<MiniFence> {
+public:
+    static const sp<MiniFence> NO_FENCE;
+
+    // Construct a new MiniFence object with an invalid file descriptor.
+    MiniFence();
+
+    // Construct a new MiniFence object to manage a given fence file descriptor.
+    // When the new MiniFence object is destructed the file descriptor will be
+    // closed.
+    explicit MiniFence(int fenceFd);
+
+    // Not copyable or movable.
+    MiniFence(const MiniFence& rhs) = delete;
+    MiniFence& operator=(const MiniFence& rhs) = delete;
+    MiniFence(MiniFence&& rhs) = delete;
+    MiniFence& operator=(MiniFence&& rhs) = delete;
+
+    // Return a duplicate of the fence file descriptor. The caller is
+    // responsible for closing the returned file descriptor. On error, -1 will
+    // be returned and errno will indicate the problem.
+    int dup() const;
+
+private:
+    // Only allow instantiation using ref counting.
+    friend class LightRefBase<MiniFence>;
+    ~MiniFence();
+
+    int mFenceFd;
+
+};
+}
+#endif //MINIFENCE_H
diff --git a/graphics/composer/2.1/utils/hwc2onfbadapter/Android.bp b/graphics/composer/2.1/utils/hwc2onfbadapter/Android.bp
new file mode 100644
index 0000000..73a41f7
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2onfbadapter/Android.bp
@@ -0,0 +1,33 @@
+// Copyright 2010 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_library_shared {
+    name: "libhwc2onfbadapter",
+    vendor: true,
+
+    clang: true,
+    cflags: [
+        "-Wall",
+        "-Wextra",
+        "-Werror",
+    ],
+
+    srcs: [
+        "HWC2OnFbAdapter.cpp",
+    ],
+
+    header_libs: ["libhardware_headers"],
+    shared_libs: ["liblog", "libsync"],
+    export_include_dirs: ["include"],
+}
diff --git a/graphics/composer/2.1/utils/hwc2onfbadapter/HWC2OnFbAdapter.cpp b/graphics/composer/2.1/utils/hwc2onfbadapter/HWC2OnFbAdapter.cpp
new file mode 100644
index 0000000..7c9e651
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2onfbadapter/HWC2OnFbAdapter.cpp
@@ -0,0 +1,887 @@
+/*
+ * Copyright 2017 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 "HWC2OnFbAdapter"
+
+//#define LOG_NDEBUG 0
+
+#include "hwc2onfbadapter/HWC2OnFbAdapter.h"
+
+#include <algorithm>
+#include <type_traits>
+
+#include <inttypes.h>
+#include <time.h>
+#include <sys/prctl.h>
+#include <unistd.h> // for close
+
+#include <hardware/fb.h>
+#include <log/log.h>
+#include <sync/sync.h>
+
+namespace android {
+
+namespace {
+
+void dumpHook(hwc2_device_t* device, uint32_t* outSize, char* outBuffer) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (outBuffer) {
+        *outSize = adapter.getDebugString().copy(outBuffer, *outSize);
+    } else {
+        adapter.updateDebugString();
+        *outSize = adapter.getDebugString().size();
+    }
+}
+
+int32_t registerCallbackHook(hwc2_device_t* device, int32_t descriptor,
+                             hwc2_callback_data_t callbackData, hwc2_function_pointer_t pointer) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    switch (descriptor) {
+        case HWC2_CALLBACK_HOTPLUG:
+            if (pointer) {
+                reinterpret_cast<HWC2_PFN_HOTPLUG>(pointer)(callbackData, adapter.getDisplayId(),
+                                                            HWC2_CONNECTION_CONNECTED);
+            }
+            break;
+        case HWC2_CALLBACK_REFRESH:
+            break;
+        case HWC2_CALLBACK_VSYNC:
+            adapter.setVsyncCallback(reinterpret_cast<HWC2_PFN_VSYNC>(pointer), callbackData);
+            break;
+        default:
+            return HWC2_ERROR_BAD_PARAMETER;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+uint32_t getMaxVirtualDisplayCountHook(hwc2_device_t* /*device*/) {
+    return 0;
+}
+
+int32_t createVirtualDisplayHook(hwc2_device_t* /*device*/, uint32_t /*width*/, uint32_t /*height*/,
+                                 int32_t* /*format*/, hwc2_display_t* /*outDisplay*/) {
+    return HWC2_ERROR_NO_RESOURCES;
+}
+
+int32_t destroyVirtualDisplayHook(hwc2_device_t* /*device*/, hwc2_display_t /*display*/) {
+    return HWC2_ERROR_BAD_DISPLAY;
+}
+
+int32_t setOutputBufferHook(hwc2_device_t* /*device*/, hwc2_display_t /*display*/,
+                            buffer_handle_t /*buffer*/, int32_t /*releaseFence*/) {
+    return HWC2_ERROR_BAD_DISPLAY;
+}
+
+int32_t getDisplayNameHook(hwc2_device_t* device, hwc2_display_t display, uint32_t* outSize,
+                           char* outName) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    const auto& info = adapter.getInfo();
+    if (outName) {
+        *outSize = info.name.copy(outName, *outSize);
+    } else {
+        *outSize = info.name.size();
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getDisplayTypeHook(hwc2_device_t* device, hwc2_display_t display, int32_t* outType) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outType = HWC2_DISPLAY_TYPE_PHYSICAL;
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getDozeSupportHook(hwc2_device_t* device, hwc2_display_t display, int32_t* outSupport) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outSupport = 0;
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getHdrCapabilitiesHook(hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumTypes,
+                               int32_t* /*outTypes*/, float* /*outMaxLuminance*/,
+                               float* /*outMaxAverageLuminance*/, float* /*outMinLuminance*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outNumTypes = 0;
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setPowerModeHook(hwc2_device_t* device, hwc2_display_t display, int32_t /*mode*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    // pretend that it works
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setVsyncEnabledHook(hwc2_device_t* device, hwc2_display_t display, int32_t enabled) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    adapter.enableVsync(enabled == HWC2_VSYNC_ENABLE);
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getColorModesHook(hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumModes,
+                          int32_t* outModes) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    if (outModes) {
+        if (*outNumModes > 0) {
+            outModes[0] = HAL_COLOR_MODE_NATIVE;
+            *outNumModes = 1;
+        }
+    } else {
+        *outNumModes = 1;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setColorModeHook(hwc2_device_t* device, hwc2_display_t display, int32_t mode) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (mode != HAL_COLOR_MODE_NATIVE) {
+        return HWC2_ERROR_BAD_PARAMETER;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setColorTransformHook(hwc2_device_t* device, hwc2_display_t display,
+                              const float* /*matrix*/, int32_t /*hint*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    // we always force client composition
+    adapter.setState(HWC2OnFbAdapter::State::MODIFIED);
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getClientTargetSupportHook(hwc2_device_t* device, hwc2_display_t display, uint32_t width,
+                                   uint32_t height, int32_t format, int32_t dataspace) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (dataspace != HAL_DATASPACE_UNKNOWN) {
+        return HWC2_ERROR_UNSUPPORTED;
+    }
+
+    const auto& info = adapter.getInfo();
+    return (info.width == width && info.height == height && info.format == format)
+            ? HWC2_ERROR_NONE
+            : HWC2_ERROR_UNSUPPORTED;
+}
+
+int32_t setClientTargetHook(hwc2_device_t* device, hwc2_display_t display, buffer_handle_t target,
+                            int32_t acquireFence, int32_t dataspace, hwc_region_t /*damage*/) {
+    if (acquireFence >= 0) {
+        sync_wait(acquireFence, -1);
+        close(acquireFence);
+    }
+
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (dataspace != HAL_DATASPACE_UNKNOWN) {
+        return HWC2_ERROR_BAD_PARAMETER;
+    }
+
+    // no state change
+    adapter.setBuffer(target);
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getDisplayConfigsHook(hwc2_device_t* device, hwc2_display_t display,
+                              uint32_t* outNumConfigs, hwc2_config_t* outConfigs) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    if (outConfigs) {
+        if (*outNumConfigs > 0) {
+            outConfigs[0] = adapter.getConfigId();
+            *outNumConfigs = 1;
+        }
+    } else {
+        *outNumConfigs = 1;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getDisplayAttributeHook(hwc2_device_t* device, hwc2_display_t display, hwc2_config_t config,
+                                int32_t attribute, int32_t* outValue) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getConfigId() != config) {
+        return HWC2_ERROR_BAD_CONFIG;
+    }
+
+    const auto& info = adapter.getInfo();
+    switch (attribute) {
+        case HWC2_ATTRIBUTE_WIDTH:
+            *outValue = int32_t(info.width);
+            break;
+        case HWC2_ATTRIBUTE_HEIGHT:
+            *outValue = int32_t(info.height);
+            break;
+        case HWC2_ATTRIBUTE_VSYNC_PERIOD:
+            *outValue = int32_t(info.vsync_period_ns);
+            break;
+        case HWC2_ATTRIBUTE_DPI_X:
+            *outValue = int32_t(info.xdpi_scaled);
+            break;
+        case HWC2_ATTRIBUTE_DPI_Y:
+            *outValue = int32_t(info.ydpi_scaled);
+            break;
+        default:
+            return HWC2_ERROR_BAD_PARAMETER;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getActiveConfigHook(hwc2_device_t* device, hwc2_display_t display,
+                            hwc2_config_t* outConfig) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outConfig = adapter.getConfigId();
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setActiveConfigHook(hwc2_device_t* device, hwc2_display_t display, hwc2_config_t config) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getConfigId() != config) {
+        return HWC2_ERROR_BAD_CONFIG;
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t validateDisplayHook(hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumTypes,
+                            uint32_t* outNumRequests) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    const auto& dirtyLayers = adapter.getDirtyLayers();
+    *outNumTypes = dirtyLayers.size();
+    *outNumRequests = 0;
+
+    if (*outNumTypes > 0) {
+        adapter.setState(HWC2OnFbAdapter::State::VALIDATED_WITH_CHANGES);
+        return HWC2_ERROR_HAS_CHANGES;
+    } else {
+        adapter.setState(HWC2OnFbAdapter::State::VALIDATED);
+        return HWC2_ERROR_NONE;
+    }
+}
+
+int32_t getChangedCompositionTypesHook(hwc2_device_t* device, hwc2_display_t display,
+                                       uint32_t* outNumElements, hwc2_layer_t* outLayers,
+                                       int32_t* outTypes) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getState() == HWC2OnFbAdapter::State::MODIFIED) {
+        return HWC2_ERROR_NOT_VALIDATED;
+    }
+
+    // request client composition for all layers
+    const auto& dirtyLayers = adapter.getDirtyLayers();
+    if (outLayers && outTypes) {
+        *outNumElements = std::min(*outNumElements, uint32_t(dirtyLayers.size()));
+        auto iter = dirtyLayers.cbegin();
+        for (uint32_t i = 0; i < *outNumElements; i++) {
+            outLayers[i] = *iter++;
+            outTypes[i] = HWC2_COMPOSITION_CLIENT;
+        }
+    } else {
+        *outNumElements = dirtyLayers.size();
+    }
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getDisplayRequestsHook(hwc2_device_t* device, hwc2_display_t display,
+                               int32_t* outDisplayRequests, uint32_t* outNumElements,
+                               hwc2_layer_t* /*outLayers*/, int32_t* /*outLayerRequests*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getState() == HWC2OnFbAdapter::State::MODIFIED) {
+        return HWC2_ERROR_NOT_VALIDATED;
+    }
+
+    *outDisplayRequests = 0;
+    *outNumElements = 0;
+    return HWC2_ERROR_NONE;
+}
+
+int32_t acceptDisplayChangesHook(hwc2_device_t* device, hwc2_display_t display) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getState() == HWC2OnFbAdapter::State::MODIFIED) {
+        return HWC2_ERROR_NOT_VALIDATED;
+    }
+
+    adapter.clearDirtyLayers();
+    adapter.setState(HWC2OnFbAdapter::State::VALIDATED);
+    return HWC2_ERROR_NONE;
+}
+
+int32_t presentDisplayHook(hwc2_device_t* device, hwc2_display_t display,
+                           int32_t* outPresentFence) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (adapter.getState() != HWC2OnFbAdapter::State::VALIDATED) {
+        return HWC2_ERROR_NOT_VALIDATED;
+    }
+
+    adapter.postBuffer();
+    *outPresentFence = -1;
+
+    return HWC2_ERROR_NONE;
+}
+
+int32_t getReleaseFencesHook(hwc2_device_t* device, hwc2_display_t display,
+                             uint32_t* outNumElements, hwc2_layer_t* /*outLayers*/,
+                             int32_t* /*outFences*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outNumElements = 0;
+    return HWC2_ERROR_NONE;
+}
+
+int32_t createLayerHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t* outLayer) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    *outLayer = adapter.addLayer();
+    adapter.setState(HWC2OnFbAdapter::State::MODIFIED);
+    return HWC2_ERROR_NONE;
+}
+
+int32_t destroyLayerHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    if (adapter.removeLayer(layer)) {
+        adapter.setState(HWC2OnFbAdapter::State::MODIFIED);
+        return HWC2_ERROR_NONE;
+    } else {
+        return HWC2_ERROR_BAD_LAYER;
+    }
+}
+
+int32_t setCursorPositionHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t /*layer*/,
+                              int32_t /*x*/, int32_t /*y*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+
+    // always an error
+    return HWC2_ERROR_BAD_LAYER;
+}
+
+int32_t setLayerBufferHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+                           buffer_handle_t /*buffer*/, int32_t acquireFence) {
+    if (acquireFence >= 0) {
+        sync_wait(acquireFence, -1);
+        close(acquireFence);
+    }
+
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (!adapter.hasLayer(layer)) {
+        return HWC2_ERROR_BAD_LAYER;
+    }
+
+    // no state change
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setLayerSurfaceDamageHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+                                  hwc_region_t /*damage*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (!adapter.hasLayer(layer)) {
+        return HWC2_ERROR_BAD_LAYER;
+    }
+
+    // no state change
+    return HWC2_ERROR_NONE;
+}
+
+int32_t setLayerCompositionTypeHook(hwc2_device_t* device, hwc2_display_t display,
+                                    hwc2_layer_t layer, int32_t type) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (!adapter.markLayerDirty(layer, type != HWC2_COMPOSITION_CLIENT)) {
+        return HWC2_ERROR_BAD_LAYER;
+    }
+
+    adapter.setState(HWC2OnFbAdapter::State::MODIFIED);
+    return HWC2_ERROR_NONE;
+}
+
+template <typename... Args>
+int32_t setLayerStateHook(hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+                          Args... /*args*/) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    if (adapter.getDisplayId() != display) {
+        return HWC2_ERROR_BAD_DISPLAY;
+    }
+    if (!adapter.hasLayer(layer)) {
+        return HWC2_ERROR_BAD_LAYER;
+    }
+
+    adapter.setState(HWC2OnFbAdapter::State::MODIFIED);
+    return HWC2_ERROR_NONE;
+}
+
+template <typename PFN, typename T>
+static hwc2_function_pointer_t asFP(T function) {
+    static_assert(std::is_same<PFN, T>::value, "Incompatible function pointer");
+    return reinterpret_cast<hwc2_function_pointer_t>(function);
+}
+
+hwc2_function_pointer_t getFunctionHook(hwc2_device_t* /*device*/, int32_t descriptor) {
+    switch (descriptor) {
+        // global functions
+        case HWC2_FUNCTION_DUMP:
+            return asFP<HWC2_PFN_DUMP>(dumpHook);
+        case HWC2_FUNCTION_REGISTER_CALLBACK:
+            return asFP<HWC2_PFN_REGISTER_CALLBACK>(registerCallbackHook);
+
+        // virtual display functions
+        case HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT:
+            return asFP<HWC2_PFN_GET_MAX_VIRTUAL_DISPLAY_COUNT>(getMaxVirtualDisplayCountHook);
+        case HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY:
+            return asFP<HWC2_PFN_CREATE_VIRTUAL_DISPLAY>(createVirtualDisplayHook);
+        case HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY:
+            return asFP<HWC2_PFN_DESTROY_VIRTUAL_DISPLAY>(destroyVirtualDisplayHook);
+        case HWC2_FUNCTION_SET_OUTPUT_BUFFER:
+            return asFP<HWC2_PFN_SET_OUTPUT_BUFFER>(setOutputBufferHook);
+
+        // display functions
+        case HWC2_FUNCTION_GET_DISPLAY_NAME:
+            return asFP<HWC2_PFN_GET_DISPLAY_NAME>(getDisplayNameHook);
+        case HWC2_FUNCTION_GET_DISPLAY_TYPE:
+            return asFP<HWC2_PFN_GET_DISPLAY_TYPE>(getDisplayTypeHook);
+        case HWC2_FUNCTION_GET_DOZE_SUPPORT:
+            return asFP<HWC2_PFN_GET_DOZE_SUPPORT>(getDozeSupportHook);
+        case HWC2_FUNCTION_GET_HDR_CAPABILITIES:
+            return asFP<HWC2_PFN_GET_HDR_CAPABILITIES>(getHdrCapabilitiesHook);
+        case HWC2_FUNCTION_SET_POWER_MODE:
+            return asFP<HWC2_PFN_SET_POWER_MODE>(setPowerModeHook);
+        case HWC2_FUNCTION_SET_VSYNC_ENABLED:
+            return asFP<HWC2_PFN_SET_VSYNC_ENABLED>(setVsyncEnabledHook);
+        case HWC2_FUNCTION_GET_COLOR_MODES:
+            return asFP<HWC2_PFN_GET_COLOR_MODES>(getColorModesHook);
+        case HWC2_FUNCTION_SET_COLOR_MODE:
+            return asFP<HWC2_PFN_SET_COLOR_MODE>(setColorModeHook);
+        case HWC2_FUNCTION_SET_COLOR_TRANSFORM:
+            return asFP<HWC2_PFN_SET_COLOR_TRANSFORM>(setColorTransformHook);
+        case HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT:
+            return asFP<HWC2_PFN_GET_CLIENT_TARGET_SUPPORT>(getClientTargetSupportHook);
+        case HWC2_FUNCTION_SET_CLIENT_TARGET:
+            return asFP<HWC2_PFN_SET_CLIENT_TARGET>(setClientTargetHook);
+
+        // config functions
+        case HWC2_FUNCTION_GET_DISPLAY_CONFIGS:
+            return asFP<HWC2_PFN_GET_DISPLAY_CONFIGS>(getDisplayConfigsHook);
+        case HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE:
+            return asFP<HWC2_PFN_GET_DISPLAY_ATTRIBUTE>(getDisplayAttributeHook);
+        case HWC2_FUNCTION_GET_ACTIVE_CONFIG:
+            return asFP<HWC2_PFN_GET_ACTIVE_CONFIG>(getActiveConfigHook);
+        case HWC2_FUNCTION_SET_ACTIVE_CONFIG:
+            return asFP<HWC2_PFN_SET_ACTIVE_CONFIG>(setActiveConfigHook);
+
+        // validate/present functions
+        case HWC2_FUNCTION_VALIDATE_DISPLAY:
+            return asFP<HWC2_PFN_VALIDATE_DISPLAY>(validateDisplayHook);
+        case HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES:
+            return asFP<HWC2_PFN_GET_CHANGED_COMPOSITION_TYPES>(getChangedCompositionTypesHook);
+        case HWC2_FUNCTION_GET_DISPLAY_REQUESTS:
+            return asFP<HWC2_PFN_GET_DISPLAY_REQUESTS>(getDisplayRequestsHook);
+        case HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES:
+            return asFP<HWC2_PFN_ACCEPT_DISPLAY_CHANGES>(acceptDisplayChangesHook);
+        case HWC2_FUNCTION_PRESENT_DISPLAY:
+            return asFP<HWC2_PFN_PRESENT_DISPLAY>(presentDisplayHook);
+        case HWC2_FUNCTION_GET_RELEASE_FENCES:
+            return asFP<HWC2_PFN_GET_RELEASE_FENCES>(getReleaseFencesHook);
+
+        // layer create/destroy
+        case HWC2_FUNCTION_CREATE_LAYER:
+            return asFP<HWC2_PFN_CREATE_LAYER>(createLayerHook);
+        case HWC2_FUNCTION_DESTROY_LAYER:
+            return asFP<HWC2_PFN_DESTROY_LAYER>(destroyLayerHook);
+
+        // layer functions; validateDisplay not required
+        case HWC2_FUNCTION_SET_CURSOR_POSITION:
+            return asFP<HWC2_PFN_SET_CURSOR_POSITION>(setCursorPositionHook);
+        case HWC2_FUNCTION_SET_LAYER_BUFFER:
+            return asFP<HWC2_PFN_SET_LAYER_BUFFER>(setLayerBufferHook);
+        case HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE:
+            return asFP<HWC2_PFN_SET_LAYER_SURFACE_DAMAGE>(setLayerSurfaceDamageHook);
+
+        // layer state functions; validateDisplay required
+        case HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE:
+            return asFP<HWC2_PFN_SET_LAYER_COMPOSITION_TYPE>(setLayerCompositionTypeHook);
+        case HWC2_FUNCTION_SET_LAYER_BLEND_MODE:
+            return asFP<HWC2_PFN_SET_LAYER_BLEND_MODE>(setLayerStateHook<int32_t>);
+        case HWC2_FUNCTION_SET_LAYER_COLOR:
+            return asFP<HWC2_PFN_SET_LAYER_COLOR>(setLayerStateHook<hwc_color_t>);
+        case HWC2_FUNCTION_SET_LAYER_DATASPACE:
+            return asFP<HWC2_PFN_SET_LAYER_DATASPACE>(setLayerStateHook<int32_t>);
+        case HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME:
+            return asFP<HWC2_PFN_SET_LAYER_DISPLAY_FRAME>(setLayerStateHook<hwc_rect_t>);
+        case HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA:
+            return asFP<HWC2_PFN_SET_LAYER_PLANE_ALPHA>(setLayerStateHook<float>);
+        case HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM:
+            return asFP<HWC2_PFN_SET_LAYER_SIDEBAND_STREAM>(setLayerStateHook<buffer_handle_t>);
+        case HWC2_FUNCTION_SET_LAYER_SOURCE_CROP:
+            return asFP<HWC2_PFN_SET_LAYER_SOURCE_CROP>(setLayerStateHook<hwc_frect_t>);
+        case HWC2_FUNCTION_SET_LAYER_TRANSFORM:
+            return asFP<HWC2_PFN_SET_LAYER_TRANSFORM>(setLayerStateHook<int32_t>);
+        case HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION:
+            return asFP<HWC2_PFN_SET_LAYER_VISIBLE_REGION>(setLayerStateHook<hwc_region_t>);
+        case HWC2_FUNCTION_SET_LAYER_Z_ORDER:
+            return asFP<HWC2_PFN_SET_LAYER_Z_ORDER>(setLayerStateHook<uint32_t>);
+
+        default:
+            ALOGE("unknown function descriptor %d", descriptor);
+            return nullptr;
+    }
+}
+
+void getCapabilitiesHook(hwc2_device_t* /*device*/, uint32_t* outCount,
+                         int32_t* /*outCapabilities*/) {
+    *outCount = 0;
+}
+
+int closeHook(hw_device_t* device) {
+    auto& adapter = HWC2OnFbAdapter::cast(device);
+    adapter.close();
+    return 0;
+}
+
+} // anonymous namespace
+
+HWC2OnFbAdapter::HWC2OnFbAdapter(framebuffer_device_t* fbDevice)
+      : hwc2_device_t(), mFbDevice(fbDevice) {
+    common.close = closeHook;
+    hwc2_device::getCapabilities = getCapabilitiesHook;
+    hwc2_device::getFunction = getFunctionHook;
+
+    mFbInfo.name = "fbdev";
+    mFbInfo.width = mFbDevice->width;
+    mFbInfo.height = mFbDevice->height;
+    mFbInfo.format = mFbDevice->format;
+    mFbInfo.vsync_period_ns = int(1e9 / mFbDevice->fps);
+    mFbInfo.xdpi_scaled = int(mFbDevice->xdpi * 1000.0f);
+    mFbInfo.ydpi_scaled = int(mFbDevice->ydpi * 1000.0f);
+
+    mVsyncThread.start(0, mFbInfo.vsync_period_ns);
+}
+
+HWC2OnFbAdapter& HWC2OnFbAdapter::cast(hw_device_t* device) {
+    return *reinterpret_cast<HWC2OnFbAdapter*>(device);
+}
+
+HWC2OnFbAdapter& HWC2OnFbAdapter::cast(hwc2_device_t* device) {
+    return *reinterpret_cast<HWC2OnFbAdapter*>(device);
+}
+
+hwc2_display_t HWC2OnFbAdapter::getDisplayId() {
+    return 0;
+}
+
+hwc2_config_t HWC2OnFbAdapter::getConfigId() {
+    return 0;
+}
+
+void HWC2OnFbAdapter::close() {
+    mVsyncThread.stop();
+    framebuffer_close(mFbDevice);
+}
+
+const HWC2OnFbAdapter::Info& HWC2OnFbAdapter::getInfo() const {
+    return mFbInfo;
+}
+
+void HWC2OnFbAdapter::updateDebugString() {
+    if (mFbDevice->common.version >= 1 && mFbDevice->dump) {
+        char buffer[4096];
+        mFbDevice->dump(mFbDevice, buffer, sizeof(buffer));
+        buffer[sizeof(buffer) - 1] = '\0';
+
+        mDebugString = buffer;
+    }
+}
+
+const std::string& HWC2OnFbAdapter::getDebugString() const {
+    return mDebugString;
+}
+
+void HWC2OnFbAdapter::setState(State state) {
+    mState = state;
+}
+
+HWC2OnFbAdapter::State HWC2OnFbAdapter::getState() const {
+    return mState;
+}
+
+hwc2_layer_t HWC2OnFbAdapter::addLayer() {
+    hwc2_layer_t id = ++mNextLayerId;
+
+    mLayers.insert(id);
+    mDirtyLayers.insert(id);
+
+    return id;
+}
+
+bool HWC2OnFbAdapter::removeLayer(hwc2_layer_t layer) {
+    mDirtyLayers.erase(layer);
+    return mLayers.erase(layer);
+}
+
+bool HWC2OnFbAdapter::hasLayer(hwc2_layer_t layer) const {
+    return mLayers.count(layer) > 0;
+}
+
+bool HWC2OnFbAdapter::markLayerDirty(hwc2_layer_t layer, bool dirty) {
+    if (mLayers.count(layer) == 0) {
+        return false;
+    }
+
+    if (dirty) {
+        mDirtyLayers.insert(layer);
+    } else {
+        mDirtyLayers.erase(layer);
+    }
+
+    return true;
+}
+
+const std::unordered_set<hwc2_layer_t>& HWC2OnFbAdapter::getDirtyLayers() const {
+    return mDirtyLayers;
+}
+
+void HWC2OnFbAdapter::clearDirtyLayers() {
+    mDirtyLayers.clear();
+}
+
+/*
+ * For each frame, SurfaceFlinger
+ *
+ *  - peforms GLES composition
+ *  - calls eglSwapBuffers
+ *  - calls setClientTarget, which maps to setBuffer below
+ *  - calls presentDisplay, which maps to postBuffer below
+ *
+ * setBuffer should be a good place to call compositionComplete.
+ *
+ * As for post, it
+ *
+ *  - schedules the buffer for presentation on the next vsync
+ *  - locks the buffer and blocks all other users trying to lock it
+ *
+ * It does not give us a way to return a present fence, and we need to live
+ * with that.  The implication is that, when we are double-buffered,
+ * SurfaceFlinger assumes the front buffer is available for rendering again
+ * immediately after the back buffer is posted.  The locking semantics
+ * hopefully are strong enough that the rendering will be blocked.
+ */
+void HWC2OnFbAdapter::setBuffer(buffer_handle_t buffer) {
+    if (mFbDevice->compositionComplete) {
+        mFbDevice->compositionComplete(mFbDevice);
+    }
+    mBuffer = buffer;
+}
+
+bool HWC2OnFbAdapter::postBuffer() {
+    int error = 0;
+    if (mBuffer) {
+        error = mFbDevice->post(mFbDevice, mBuffer);
+    }
+
+    return error == 0;
+}
+
+void HWC2OnFbAdapter::setVsyncCallback(HWC2_PFN_VSYNC callback, hwc2_callback_data_t data) {
+    mVsyncThread.setCallback(callback, data);
+}
+
+void HWC2OnFbAdapter::enableVsync(bool enable) {
+    mVsyncThread.enableCallback(enable);
+}
+
+int64_t HWC2OnFbAdapter::VsyncThread::now() {
+    struct timespec ts;
+    clock_gettime(CLOCK_MONOTONIC, &ts);
+
+    return int64_t(ts.tv_sec) * 1'000'000'000 + ts.tv_nsec;
+}
+
+bool HWC2OnFbAdapter::VsyncThread::sleepUntil(int64_t t) {
+    struct timespec ts;
+    ts.tv_sec = t / 1'000'000'000;
+    ts.tv_nsec = t % 1'000'000'000;
+
+    while (true) {
+        int error = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &ts, nullptr);
+        if (error) {
+            if (error == EINTR) {
+                continue;
+            }
+            return false;
+        } else {
+            return true;
+        }
+    }
+}
+
+void HWC2OnFbAdapter::VsyncThread::start(int64_t firstVsync, int64_t period) {
+    mNextVsync = firstVsync;
+    mPeriod = period;
+    mStarted = true;
+    mThread = std::thread(&VsyncThread::vsyncLoop, this);
+}
+
+void HWC2OnFbAdapter::VsyncThread::stop() {
+    {
+        std::lock_guard<std::mutex> lock(mMutex);
+        mStarted = false;
+    }
+    mCondition.notify_all();
+    mThread.join();
+}
+
+void HWC2OnFbAdapter::VsyncThread::setCallback(HWC2_PFN_VSYNC callback, hwc2_callback_data_t data) {
+    std::lock_guard<std::mutex> lock(mMutex);
+    mCallback = callback;
+    mCallbackData = data;
+}
+
+void HWC2OnFbAdapter::VsyncThread::enableCallback(bool enable) {
+    {
+        std::lock_guard<std::mutex> lock(mMutex);
+        mCallbackEnabled = enable;
+    }
+    mCondition.notify_all();
+}
+
+void HWC2OnFbAdapter::VsyncThread::vsyncLoop() {
+    prctl(PR_SET_NAME, "VsyncThread", 0, 0, 0);
+
+    std::unique_lock<std::mutex> lock(mMutex);
+    if (!mStarted) {
+        return;
+    }
+
+    while (true) {
+        if (!mCallbackEnabled) {
+            mCondition.wait(lock, [this] { return mCallbackEnabled || !mStarted; });
+            if (!mStarted) {
+                break;
+            }
+        }
+
+        lock.unlock();
+
+        // adjust mNextVsync if necessary
+        int64_t t = now();
+        if (mNextVsync < t) {
+            int64_t n = (t - mNextVsync + mPeriod - 1) / mPeriod;
+            mNextVsync += mPeriod * n;
+        }
+        bool fire = sleepUntil(mNextVsync);
+
+        lock.lock();
+
+        if (fire) {
+            ALOGV("VsyncThread(%" PRId64 ")", mNextVsync);
+            if (mCallback) {
+                mCallback(mCallbackData, getDisplayId(), mNextVsync);
+            }
+            mNextVsync += mPeriod;
+        }
+    }
+}
+
+} // namespace android
diff --git a/graphics/composer/2.1/utils/hwc2onfbadapter/include/hwc2onfbadapter/HWC2OnFbAdapter.h b/graphics/composer/2.1/utils/hwc2onfbadapter/include/hwc2onfbadapter/HWC2OnFbAdapter.h
new file mode 100644
index 0000000..d6272fd
--- /dev/null
+++ b/graphics/composer/2.1/utils/hwc2onfbadapter/include/hwc2onfbadapter/HWC2OnFbAdapter.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SF_HWC2_ON_FB_ADAPTER_H
+#define ANDROID_SF_HWC2_ON_FB_ADAPTER_H
+
+#include <condition_variable>
+#include <mutex>
+#include <string>
+#include <thread>
+#include <unordered_set>
+
+#include <hardware/hwcomposer2.h>
+
+struct framebuffer_device_t;
+
+namespace android {
+
+class HWC2OnFbAdapter : public hwc2_device_t {
+public:
+    HWC2OnFbAdapter(framebuffer_device_t* fbDevice);
+
+    static HWC2OnFbAdapter& cast(hw_device_t* device);
+    static HWC2OnFbAdapter& cast(hwc2_device_t* device);
+
+    static hwc2_display_t getDisplayId();
+    static hwc2_config_t getConfigId();
+
+    void close();
+
+    struct Info {
+        std::string name;
+        uint32_t width;
+        uint32_t height;
+        int format;
+        int vsync_period_ns;
+        int xdpi_scaled;
+        int ydpi_scaled;
+    };
+    const Info& getInfo() const;
+
+    void updateDebugString();
+    const std::string& getDebugString() const;
+
+    enum class State {
+        MODIFIED,
+        VALIDATED_WITH_CHANGES,
+        VALIDATED,
+    };
+    void setState(State state);
+    State getState() const;
+
+    hwc2_layer_t addLayer();
+    bool removeLayer(hwc2_layer_t layer);
+    bool hasLayer(hwc2_layer_t layer) const;
+    bool markLayerDirty(hwc2_layer_t layer, bool dirty);
+    const std::unordered_set<hwc2_layer_t>& getDirtyLayers() const;
+    void clearDirtyLayers();
+
+    void setBuffer(buffer_handle_t buffer);
+    bool postBuffer();
+
+    void setVsyncCallback(HWC2_PFN_VSYNC callback, hwc2_callback_data_t data);
+    void enableVsync(bool enable);
+
+private:
+    framebuffer_device_t* mFbDevice{nullptr};
+    Info mFbInfo{};
+
+    std::string mDebugString;
+
+    State mState{State::MODIFIED};
+
+    uint64_t mNextLayerId{0};
+    std::unordered_set<hwc2_layer_t> mLayers;
+    std::unordered_set<hwc2_layer_t> mDirtyLayers;
+
+    buffer_handle_t mBuffer{nullptr};
+
+    class VsyncThread {
+    public:
+        static int64_t now();
+        static bool sleepUntil(int64_t t);
+
+        void start(int64_t first, int64_t period);
+        void stop();
+        void setCallback(HWC2_PFN_VSYNC callback, hwc2_callback_data_t data);
+        void enableCallback(bool enable);
+
+    private:
+        void vsyncLoop();
+        bool waitUntilNextVsync();
+
+        std::thread mThread;
+        int64_t mNextVsync{0};
+        int64_t mPeriod{0};
+
+        std::mutex mMutex;
+        std::condition_variable mCondition;
+        bool mStarted{false};
+        HWC2_PFN_VSYNC mCallback{nullptr};
+        hwc2_callback_data_t mCallbackData{nullptr};
+        bool mCallbackEnabled{false};
+    };
+    VsyncThread mVsyncThread;
+};
+
+} // namespace android
+
+#endif // ANDROID_SF_HWC2_ON_FB_ADAPTER_H