diff --git a/libs/gui/Android.bp b/libs/gui/Android.bp
index 4558fe8..ed2f30a 100644
--- a/libs/gui/Android.bp
+++ b/libs/gui/Android.bp
@@ -93,6 +93,7 @@
         "IProducerListener.cpp",
         "ISurfaceComposer.cpp",
         "ISurfaceComposerClient.cpp",
+        "LayerDebugInfo.cpp",
         "LayerState.cpp",
         "OccupancyTracker.cpp",
         "StreamSplitter.cpp",
diff --git a/libs/gui/ISurfaceComposer.cpp b/libs/gui/ISurfaceComposer.cpp
index 0a0d112..8e7f814 100644
--- a/libs/gui/ISurfaceComposer.cpp
+++ b/libs/gui/ISurfaceComposer.cpp
@@ -28,6 +28,7 @@
 #include <gui/IGraphicBufferProducer.h>
 #include <gui/ISurfaceComposer.h>
 #include <gui/ISurfaceComposerClient.h>
+#include <gui/LayerDebugInfo.h>
 
 #include <private/gui/LayerState.h>
 
@@ -469,6 +470,36 @@
         return result;
     }
 
+    virtual status_t getLayerDebugInfo(std::vector<LayerDebugInfo>* outLayers) const
+    {
+        if (!outLayers) {
+            return UNEXPECTED_NULL;
+        }
+
+        Parcel data, reply;
+
+        status_t err = data.writeInterfaceToken(ISurfaceComposer::getInterfaceDescriptor());
+        if (err != NO_ERROR) {
+            return err;
+        }
+
+        err = remote()->transact(BnSurfaceComposer::GET_LAYER_DEBUG_INFO, data, &reply);
+        if (err != NO_ERROR) {
+            return err;
+        }
+
+        int32_t result = 0;
+        err = reply.readInt32(&result);
+        if (err != NO_ERROR) {
+            return err;
+        }
+        if (result != NO_ERROR) {
+            return result;
+        }
+
+        outLayers->clear();
+        return reply.readParcelableVector(outLayers);
+    }
 };
 
 // Out-of-line virtual method definition to trigger vtable emission in this
@@ -763,6 +794,17 @@
             }
             return injectVSync(when);
         }
+        case GET_LAYER_DEBUG_INFO: {
+            CHECK_INTERFACE(ISurfaceComposer, data, reply);
+            std::vector<LayerDebugInfo> outLayers;
+            status_t result = getLayerDebugInfo(&outLayers);
+            reply->writeInt32(result);
+            if (result == NO_ERROR)
+            {
+                result = reply->writeParcelableVector(outLayers);
+            }
+            return result;
+        }
         default: {
             return BBinder::onTransact(code, data, reply, flags);
         }
diff --git a/libs/gui/LayerDebugInfo.cpp b/libs/gui/LayerDebugInfo.cpp
new file mode 100644
index 0000000..57ddde0
--- /dev/null
+++ b/libs/gui/LayerDebugInfo.cpp
@@ -0,0 +1,136 @@
+/*
+ * 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 <gui/LayerDebugInfo.h>
+
+#include <ui/DebugUtils.h>
+
+#include <binder/Parcel.h>
+
+#include <utils/String8.h>
+
+using namespace android;
+
+#define RETURN_ON_ERROR(X) do {status_t res = (X); if (res != NO_ERROR) return res;} while(false)
+
+namespace android {
+
+status_t LayerDebugInfo::writeToParcel(Parcel* parcel) const {
+    RETURN_ON_ERROR(parcel->writeCString(mName.c_str()));
+    RETURN_ON_ERROR(parcel->writeCString(mParentName.c_str()));
+    RETURN_ON_ERROR(parcel->writeCString(mType.c_str()));
+    RETURN_ON_ERROR(parcel->write(mTransparentRegion));
+    RETURN_ON_ERROR(parcel->write(mVisibleRegion));
+    RETURN_ON_ERROR(parcel->write(mSurfaceDamageRegion));
+    RETURN_ON_ERROR(parcel->writeUint32(mLayerStack));
+    RETURN_ON_ERROR(parcel->writeFloat(mX));
+    RETURN_ON_ERROR(parcel->writeFloat(mY));
+    RETURN_ON_ERROR(parcel->writeUint32(mZ));
+    RETURN_ON_ERROR(parcel->writeInt32(mWidth));
+    RETURN_ON_ERROR(parcel->writeInt32(mHeight));
+    RETURN_ON_ERROR(parcel->write(mCrop));
+    RETURN_ON_ERROR(parcel->write(mFinalCrop));
+    RETURN_ON_ERROR(parcel->writeFloat(mAlpha));
+    RETURN_ON_ERROR(parcel->writeUint32(mFlags));
+    RETURN_ON_ERROR(parcel->writeInt32(mPixelFormat));
+    RETURN_ON_ERROR(parcel->writeUint32(static_cast<uint32_t>(mDataSpace)));
+    for (size_t index = 0; index < 4; index++) {
+        RETURN_ON_ERROR(parcel->writeFloat(mMatrix[index / 2][index % 2]));
+    }
+    RETURN_ON_ERROR(parcel->writeInt32(mActiveBufferWidth));
+    RETURN_ON_ERROR(parcel->writeInt32(mActiveBufferHeight));
+    RETURN_ON_ERROR(parcel->writeInt32(mActiveBufferStride));
+    RETURN_ON_ERROR(parcel->writeInt32(mActiveBufferFormat));
+    RETURN_ON_ERROR(parcel->writeInt32(mNumQueuedFrames));
+    RETURN_ON_ERROR(parcel->writeBool(mRefreshPending));
+    RETURN_ON_ERROR(parcel->writeBool(mIsOpaque));
+    RETURN_ON_ERROR(parcel->writeBool(mContentDirty));
+    return NO_ERROR;
+}
+
+status_t LayerDebugInfo::readFromParcel(const Parcel* parcel) {
+    mName = parcel->readCString();
+    RETURN_ON_ERROR(parcel->errorCheck());
+    mParentName = parcel->readCString();
+    RETURN_ON_ERROR(parcel->errorCheck());
+    mType = parcel->readCString();
+    RETURN_ON_ERROR(parcel->errorCheck());
+    RETURN_ON_ERROR(parcel->read(mTransparentRegion));
+    RETURN_ON_ERROR(parcel->read(mVisibleRegion));
+    RETURN_ON_ERROR(parcel->read(mSurfaceDamageRegion));
+    RETURN_ON_ERROR(parcel->readUint32(&mLayerStack));
+    RETURN_ON_ERROR(parcel->readFloat(&mX));
+    RETURN_ON_ERROR(parcel->readFloat(&mY));
+    RETURN_ON_ERROR(parcel->readUint32(&mZ));
+    RETURN_ON_ERROR(parcel->readInt32(&mWidth));
+    RETURN_ON_ERROR(parcel->readInt32(&mHeight));
+    RETURN_ON_ERROR(parcel->read(mCrop));
+    RETURN_ON_ERROR(parcel->read(mFinalCrop));
+    RETURN_ON_ERROR(parcel->readFloat(&mAlpha));
+    RETURN_ON_ERROR(parcel->readUint32(&mFlags));
+    RETURN_ON_ERROR(parcel->readInt32(&mPixelFormat));
+    // \todo [2017-07-25 kraita]: Static casting mDataSpace pointer to an uint32 does work. Better ways?
+    mDataSpace = static_cast<android_dataspace>(parcel->readUint32());
+    RETURN_ON_ERROR(parcel->errorCheck());
+    for (size_t index = 0; index < 4; index++) {
+        RETURN_ON_ERROR(parcel->readFloat(&mMatrix[index / 2][index % 2]));
+    }
+    RETURN_ON_ERROR(parcel->readInt32(&mActiveBufferWidth));
+    RETURN_ON_ERROR(parcel->readInt32(&mActiveBufferHeight));
+    RETURN_ON_ERROR(parcel->readInt32(&mActiveBufferStride));
+    RETURN_ON_ERROR(parcel->readInt32(&mActiveBufferFormat));
+    RETURN_ON_ERROR(parcel->readInt32(&mNumQueuedFrames));
+    RETURN_ON_ERROR(parcel->readBool(&mRefreshPending));
+    RETURN_ON_ERROR(parcel->readBool(&mIsOpaque));
+    RETURN_ON_ERROR(parcel->readBool(&mContentDirty));
+    return NO_ERROR;
+}
+
+std::string to_string(const LayerDebugInfo& info) {
+    String8 result;
+
+    result.appendFormat("+ %s (%s)\n", info.mType.c_str(), info.mName.c_str());
+    info.mTransparentRegion.dump(result, "TransparentRegion");
+    info.mVisibleRegion.dump(result, "VisibleRegion");
+    info.mSurfaceDamageRegion.dump(result, "SurfaceDamageRegion");
+
+    result.appendFormat("      layerStack=%4d, z=%9d, pos=(%g,%g), size=(%4d,%4d), ",
+            info.mLayerStack, info.mZ, static_cast<double>(info.mX), static_cast<double>(info.mY),
+            info.mWidth, info.mHeight);
+
+    result.appendFormat("crop=%s, finalCrop=%s, ",
+            to_string(info.mCrop).c_str(), to_string(info.mFinalCrop).c_str());
+    result.appendFormat("isOpaque=%1d, invalidate=%1d, ", info.mIsOpaque, info.mContentDirty);
+    result.appendFormat("dataspace=%s, ", dataspaceDetails(info.mDataSpace).c_str());
+    result.appendFormat("pixelformat=%s, ", decodePixelFormat(info.mPixelFormat).c_str());
+    result.appendFormat("alpha=%.3f, flags=0x%08x, ",
+            static_cast<double>(info.mAlpha), info.mFlags);
+    result.appendFormat("tr=[%.2f, %.2f][%.2f, %.2f]",
+            static_cast<double>(info.mMatrix[0][0]), static_cast<double>(info.mMatrix[0][1]),
+            static_cast<double>(info.mMatrix[1][0]), static_cast<double>(info.mMatrix[1][1]));
+    result.append("\n");
+    result.appendFormat("      parent=%s\n", info.mParentName.c_str());
+    result.appendFormat("      activeBuffer=[%4ux%4u:%4u,%s],",
+            info.mActiveBufferWidth, info.mActiveBufferHeight,
+            info.mActiveBufferStride,
+            decodePixelFormat(info.mActiveBufferFormat).c_str());
+    result.appendFormat(" queued-frames=%d, mRefreshPending=%d",
+            info.mNumQueuedFrames, info.mRefreshPending);
+    result.append("\n");
+    return std::string(result.c_str());
+}
+
+} // android
diff --git a/libs/gui/include/gui/ISurfaceComposer.h b/libs/gui/include/gui/ISurfaceComposer.h
index f80ba00..b226742 100644
--- a/libs/gui/include/gui/ISurfaceComposer.h
+++ b/libs/gui/include/gui/ISurfaceComposer.h
@@ -39,6 +39,7 @@
 struct DisplayState;
 struct DisplayInfo;
 struct DisplayStatInfo;
+class LayerDebugInfo;
 class HdrCapabilities;
 class IDisplayEventConnection;
 class IGraphicBufferProducer;
@@ -195,6 +196,12 @@
     virtual status_t enableVSyncInjections(bool enable) = 0;
 
     virtual status_t injectVSync(nsecs_t when) = 0;
+
+    /* Gets the list of active layers in Z order for debugging purposes
+     *
+     * Requires the ACCESS_SURFACE_FLINGER permission.
+     */
+    virtual status_t getLayerDebugInfo(std::vector<LayerDebugInfo>* outLayers) const = 0;
 };
 
 // ----------------------------------------------------------------------------
@@ -229,6 +236,7 @@
         SET_ACTIVE_COLOR_MODE,
         ENABLE_VSYNC_INJECTIONS,
         INJECT_VSYNC,
+        GET_LAYER_DEBUG_INFO,
         CREATE_SCOPED_CONNECTION
     };
 
diff --git a/libs/gui/include/gui/LayerDebugInfo.h b/libs/gui/include/gui/LayerDebugInfo.h
new file mode 100644
index 0000000..8453e04
--- /dev/null
+++ b/libs/gui/include/gui/LayerDebugInfo.h
@@ -0,0 +1,73 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+#include <binder/Parcelable.h>
+
+#include <ui/PixelFormat.h>
+#include <ui/Region.h>
+
+#include <string>
+
+namespace android {
+
+/* Class for transporting debug info from SurfaceFlinger to authorized
+ * recipients.  The class is intended to be a data container. There are
+ * no getters or setters.
+ */
+class LayerDebugInfo : public Parcelable {
+public:
+    LayerDebugInfo() = default;
+    LayerDebugInfo(const LayerDebugInfo&) = default;
+    virtual ~LayerDebugInfo() = default;
+
+    virtual status_t writeToParcel(Parcel* parcel) const;
+    virtual status_t readFromParcel(const Parcel* parcel);
+
+    std::string mName = std::string("NOT FILLED");
+    std::string mParentName = std::string("NOT FILLED");
+    std::string mType = std::string("NOT FILLED");
+    Region mTransparentRegion = Region::INVALID_REGION;
+    Region mVisibleRegion = Region::INVALID_REGION;
+    Region mSurfaceDamageRegion = Region::INVALID_REGION;
+    uint32_t mLayerStack = 0;
+    float mX = 0.f;
+    float mY = 0.f;
+    uint32_t mZ = 0 ;
+    int32_t mWidth = -1;
+    int32_t mHeight = -1;
+    Rect mCrop = Rect::INVALID_RECT;
+    Rect mFinalCrop = Rect::INVALID_RECT;
+    float mAlpha = 0.f;
+    uint32_t mFlags = 0;
+    PixelFormat mPixelFormat = PIXEL_FORMAT_NONE;
+    android_dataspace mDataSpace = HAL_DATASPACE_UNKNOWN;
+    // Row-major transform matrix (SurfaceControl::setMatrix())
+    float mMatrix[2][2] = {{0.f, 0.f}, {0.f, 0.f}};
+    int32_t mActiveBufferWidth = -1;
+    int32_t mActiveBufferHeight = -1;
+    int32_t mActiveBufferStride = 0;
+    PixelFormat mActiveBufferFormat = PIXEL_FORMAT_NONE;
+    int32_t mNumQueuedFrames = -1;
+    bool mRefreshPending = false;
+    bool mIsOpaque = false;
+    bool mContentDirty = false;
+};
+
+std::string to_string(const LayerDebugInfo& info);
+
+} // namespace android
diff --git a/libs/gui/include/gui/SurfaceControl.h b/libs/gui/include/gui/SurfaceControl.h
index 8bb705c..c15209d 100644
--- a/libs/gui/include/gui/SurfaceControl.h
+++ b/libs/gui/include/gui/SurfaceControl.h
@@ -90,6 +90,16 @@
     status_t    setFlags(uint32_t flags, uint32_t mask);
     status_t    setTransparentRegionHint(const Region& transparent);
     status_t    setAlpha(float alpha=1.0f);
+
+    // Experimentarily it appears that the matrix transforms the
+    // on-screen rectangle and it's contents before the position is
+    // applied.
+    //
+    // TODO: Test with other combinations to find approximate transformation rules.
+    //
+    // For example:
+    // Layer sized (W,H) set to position (x,y) with matrix M=[-1, 0, 0, 1] (Horizontal flip) gives
+    // [((0, 0), (W, H)) x M] + (x,y) = ((-W, 0), (0, H)) + (x,y) = ((-W + x, y), (x, H+y))
     status_t    setMatrix(float dsdx, float dtdx, float dtdy, float dsdy);
     status_t    setCrop(const Rect& crop);
     status_t    setFinalCrop(const Rect& crop);
diff --git a/libs/gui/tests/Surface_test.cpp b/libs/gui/tests/Surface_test.cpp
index e18af17..45e95a5 100644
--- a/libs/gui/tests/Surface_test.cpp
+++ b/libs/gui/tests/Surface_test.cpp
@@ -539,6 +539,9 @@
         return NO_ERROR;
     }
     status_t injectVSync(nsecs_t /*when*/) override { return NO_ERROR; }
+    status_t getLayerDebugInfo(std::vector<LayerDebugInfo>* /*layers*/) const override {
+        return NO_ERROR;
+    }
 
 protected:
     IBinder* onAsBinder() override { return nullptr; }
diff --git a/libs/ui/DebugUtils.cpp b/libs/ui/DebugUtils.cpp
index 6e31d2a..2d72944 100644
--- a/libs/ui/DebugUtils.cpp
+++ b/libs/ui/DebugUtils.cpp
@@ -16,10 +16,13 @@
 
 #include <ui/DebugUtils.h>
 #include <ui/PixelFormat.h>
+#include <ui/Rect.h>
 
 #include <android-base/stringprintf.h>
 #include <string>
 
+using android::base::StringPrintf;
+
 std::string decodeStandard(android_dataspace dataspace) {
     const uint32_t dataspaceSelect = (dataspace & HAL_DATASPACE_STANDARD_MASK);
     switch (dataspaceSelect) {
@@ -262,3 +265,7 @@
             return android::base::StringPrintf("Unknown %#08x", format);
     }
 }
+
+std::string to_string(const android::Rect& rect) {
+    return StringPrintf("(%4d,%4d,%4d,%4d)", rect.left, rect.top, rect.right, rect.bottom);
+}
diff --git a/libs/ui/include/ui/DebugUtils.h b/libs/ui/include/ui/DebugUtils.h
index 30f4a59..dad9446 100644
--- a/libs/ui/include/ui/DebugUtils.h
+++ b/libs/ui/include/ui/DebugUtils.h
@@ -21,9 +21,14 @@
 
 #include <string>
 
+namespace android {
+class Rect;
+}
+
 std::string decodeStandard(android_dataspace dataspace);
 std::string decodeTransfer(android_dataspace dataspace);
 std::string decodeRange(android_dataspace dataspace);
 std::string dataspaceDetails(android_dataspace dataspace);
 std::string decodeColorMode(android_color_mode colormode);
 std::string decodePixelFormat(android::PixelFormat format);
+std::string to_string(const android::Rect& rect);