diff --git a/libs/nativewindow/AHardwareBuffer.cpp b/libs/nativewindow/AHardwareBuffer.cpp
index b4b5303..3fbab17 100644
--- a/libs/nativewindow/AHardwareBuffer.cpp
+++ b/libs/nativewindow/AHardwareBuffer.cpp
@@ -57,7 +57,8 @@
 
     uint64_t producerUsage = 0;
     uint64_t consumerUsage = 0;
-    AHardwareBuffer_convertToGrallocUsageBits(desc->usage0, &producerUsage, &consumerUsage);
+    AHardwareBuffer_convertToGrallocUsageBits(&producerUsage, &consumerUsage, desc->usage0,
+            desc->usage1);
 
     sp<GraphicBuffer> gbuffer(new GraphicBuffer(
             desc->width, desc->height, format, desc->layers, producerUsage, consumerUsage,
@@ -97,9 +98,8 @@
     outDesc->width = gbuffer->getWidth();
     outDesc->height = gbuffer->getHeight();
     outDesc->layers = gbuffer->getLayerCount();
-    outDesc->usage0 = AHardwareBuffer_convertFromGrallocUsageBits(
+    AHardwareBuffer_convertFromGrallocUsageBits(&outDesc->usage0, &outDesc->usage1,
             gbuffer->getUsage(), gbuffer->getUsage());
-    outDesc->usage1 = 0;
     outDesc->format = AHardwareBuffer_convertFromPixelFormat(
             static_cast<uint32_t>(gbuffer->getPixelFormat()));
 }
@@ -117,7 +117,7 @@
 
     uint64_t producerUsage = 0;
     uint64_t consumerUsage = 0;
-    AHardwareBuffer_convertToGrallocUsageBits(usage0, &producerUsage, &consumerUsage);
+    AHardwareBuffer_convertToGrallocUsageBits(&producerUsage, &consumerUsage, usage0, 0);
     GraphicBuffer* gBuffer = AHardwareBuffer_to_GraphicBuffer(buffer);
     Rect bounds;
     if (!rect) {
@@ -268,8 +268,76 @@
 
 namespace android {
 
+// A 1:1 mapping of AHardwaqreBuffer bitmasks to gralloc1 bitmasks.
+struct UsageMaskMapping {
+    uint64_t hardwareBufferMask;
+    uint64_t grallocMask;
+};
+
+static constexpr UsageMaskMapping kUsage0ProducerMapping[] = {
+    { AHARDWAREBUFFER_USAGE0_CPU_WRITE, GRALLOC1_PRODUCER_USAGE_CPU_WRITE },
+    { AHARDWAREBUFFER_USAGE0_CPU_WRITE_OFTEN, GRALLOC1_PRODUCER_USAGE_CPU_WRITE_OFTEN },
+    { AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT, GRALLOC1_PRODUCER_USAGE_GPU_RENDER_TARGET },
+    { AHARDWAREBUFFER_USAGE0_PROTECTED_CONTENT, GRALLOC1_PRODUCER_USAGE_PROTECTED },
+    { AHARDWAREBUFFER_USAGE0_SENSOR_DIRECT_DATA, GRALLOC1_PRODUCER_USAGE_SENSOR_DIRECT_DATA },
+};
+
+static constexpr UsageMaskMapping kUsage1ProducerMapping[] = {
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_0, GRALLOC1_PRODUCER_USAGE_PRIVATE_0 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_1, GRALLOC1_PRODUCER_USAGE_PRIVATE_1 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_2, GRALLOC1_PRODUCER_USAGE_PRIVATE_2 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_3, GRALLOC1_PRODUCER_USAGE_PRIVATE_3 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_4, GRALLOC1_PRODUCER_USAGE_PRIVATE_4 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_5, GRALLOC1_PRODUCER_USAGE_PRIVATE_5 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_6, GRALLOC1_PRODUCER_USAGE_PRIVATE_6 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_7, GRALLOC1_PRODUCER_USAGE_PRIVATE_7 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_8, GRALLOC1_PRODUCER_USAGE_PRIVATE_8 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_9, GRALLOC1_PRODUCER_USAGE_PRIVATE_9 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_10, GRALLOC1_PRODUCER_USAGE_PRIVATE_10 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_11, GRALLOC1_PRODUCER_USAGE_PRIVATE_11 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_12, GRALLOC1_PRODUCER_USAGE_PRIVATE_12 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_13, GRALLOC1_PRODUCER_USAGE_PRIVATE_13 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_14, GRALLOC1_PRODUCER_USAGE_PRIVATE_14 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_15, GRALLOC1_PRODUCER_USAGE_PRIVATE_15 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_16, GRALLOC1_PRODUCER_USAGE_PRIVATE_16 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_17, GRALLOC1_PRODUCER_USAGE_PRIVATE_17 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_18, GRALLOC1_PRODUCER_USAGE_PRIVATE_18 },
+    { AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_19, GRALLOC1_PRODUCER_USAGE_PRIVATE_19 },
+};
+
+static constexpr UsageMaskMapping kUsage0ConsumerMapping[] = {
+    { AHARDWAREBUFFER_USAGE0_CPU_READ, GRALLOC1_CONSUMER_USAGE_CPU_READ },
+    { AHARDWAREBUFFER_USAGE0_CPU_READ_OFTEN, GRALLOC1_CONSUMER_USAGE_CPU_READ_OFTEN },
+    { AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE, GRALLOC1_CONSUMER_USAGE_GPU_TEXTURE },
+    { AHARDWAREBUFFER_USAGE0_GPU_DATA_BUFFER, GRALLOC1_CONSUMER_USAGE_GPU_DATA_BUFFER },
+    { AHARDWAREBUFFER_USAGE0_VIDEO_ENCODE, GRALLOC1_CONSUMER_USAGE_VIDEO_ENCODER },
+};
+
+static constexpr UsageMaskMapping kUsage1ConsumerMapping[] = {
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_0, GRALLOC1_CONSUMER_USAGE_PRIVATE_0 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_1, GRALLOC1_CONSUMER_USAGE_PRIVATE_1 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_2, GRALLOC1_CONSUMER_USAGE_PRIVATE_2 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_3, GRALLOC1_CONSUMER_USAGE_PRIVATE_3 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_4, GRALLOC1_CONSUMER_USAGE_PRIVATE_4 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_5, GRALLOC1_CONSUMER_USAGE_PRIVATE_5 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_6, GRALLOC1_CONSUMER_USAGE_PRIVATE_6 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_7, GRALLOC1_CONSUMER_USAGE_PRIVATE_7 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_8, GRALLOC1_CONSUMER_USAGE_PRIVATE_8 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_9, GRALLOC1_CONSUMER_USAGE_PRIVATE_9 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_10, GRALLOC1_CONSUMER_USAGE_PRIVATE_10 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_11, GRALLOC1_CONSUMER_USAGE_PRIVATE_11 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_12, GRALLOC1_CONSUMER_USAGE_PRIVATE_12 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_13, GRALLOC1_CONSUMER_USAGE_PRIVATE_13 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_14, GRALLOC1_CONSUMER_USAGE_PRIVATE_14 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_15, GRALLOC1_CONSUMER_USAGE_PRIVATE_15 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_16, GRALLOC1_CONSUMER_USAGE_PRIVATE_16 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_17, GRALLOC1_CONSUMER_USAGE_PRIVATE_17 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_18, GRALLOC1_CONSUMER_USAGE_PRIVATE_18 },
+    { AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_19, GRALLOC1_CONSUMER_USAGE_PRIVATE_19 },
+};
+
 static inline bool containsBits(uint64_t mask, uint64_t bitsToCheck) {
-    return (mask & bitsToCheck) == bitsToCheck;
+    return (mask & bitsToCheck) == bitsToCheck && bitsToCheck;
 }
 
 uint32_t AHardwareBuffer_convertFromPixelFormat(uint32_t format) {
@@ -300,58 +368,56 @@
     }
 }
 
-void AHardwareBuffer_convertToGrallocUsageBits(uint64_t usage, uint64_t* outProducerUsage,
-        uint64_t* outConsumerUsage) {
+void AHardwareBuffer_convertToGrallocUsageBits(uint64_t* outProducerUsage,
+    uint64_t* outConsumerUsage, uint64_t usage0, uint64_t usage1) {
     *outProducerUsage = 0;
     *outConsumerUsage = 0;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_CPU_READ))
-        *outConsumerUsage |= GRALLOC1_CONSUMER_USAGE_CPU_READ;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_CPU_READ_OFTEN))
-        *outConsumerUsage |= GRALLOC1_CONSUMER_USAGE_CPU_READ_OFTEN;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_CPU_WRITE))
-        *outProducerUsage |= GRALLOC1_PRODUCER_USAGE_CPU_WRITE;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_CPU_WRITE_OFTEN))
-        *outProducerUsage |= GRALLOC1_PRODUCER_USAGE_CPU_WRITE_OFTEN;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE))
-        *outConsumerUsage |= GRALLOC1_CONSUMER_USAGE_GPU_TEXTURE;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT))
-        *outProducerUsage |= GRALLOC1_PRODUCER_USAGE_GPU_RENDER_TARGET;
-    // Not sure what this should be.
-    //if (containsBits(usage0, AHARDWAREBUFFER_USAGE0_GPU_CUBEMAP)) bits |= 0;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_GPU_DATA_BUFFER))
-        *outConsumerUsage |= GRALLOC1_CONSUMER_USAGE_GPU_DATA_BUFFER;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_VIDEO_ENCODE))
-        *outConsumerUsage |= GRALLOC1_CONSUMER_USAGE_VIDEO_ENCODER;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_PROTECTED_CONTENT))
-        *outProducerUsage |= GRALLOC1_PRODUCER_USAGE_PROTECTED;
-    if (containsBits(usage, AHARDWAREBUFFER_USAGE0_SENSOR_DIRECT_DATA))
-        *outProducerUsage |= GRALLOC1_PRODUCER_USAGE_SENSOR_DIRECT_DATA;
+    for (const UsageMaskMapping& mapping : kUsage0ProducerMapping) {
+        if (containsBits(usage0, mapping.hardwareBufferMask)) {
+            *outProducerUsage |= mapping.grallocMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage1ProducerMapping) {
+        if (containsBits(usage1, mapping.hardwareBufferMask)) {
+            *outProducerUsage |= mapping.grallocMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage0ConsumerMapping) {
+        if (containsBits(usage0, mapping.hardwareBufferMask)) {
+            *outConsumerUsage |= mapping.grallocMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage1ConsumerMapping) {
+        if (containsBits(usage1, mapping.hardwareBufferMask)) {
+            *outConsumerUsage |= mapping.grallocMask;
+        }
+    }
 }
 
-uint64_t AHardwareBuffer_convertFromGrallocUsageBits(uint64_t producerUsage, uint64_t consumerUsage) {
-    uint64_t bits = 0;
-    if (containsBits(consumerUsage, GRALLOC1_CONSUMER_USAGE_CPU_READ))
-        bits |= AHARDWAREBUFFER_USAGE0_CPU_READ;
-    if (containsBits(consumerUsage, GRALLOC1_CONSUMER_USAGE_CPU_READ_OFTEN))
-        bits |= AHARDWAREBUFFER_USAGE0_CPU_READ_OFTEN;
-    if (containsBits(producerUsage, GRALLOC1_PRODUCER_USAGE_CPU_WRITE))
-        bits |= AHARDWAREBUFFER_USAGE0_CPU_WRITE;
-    if (containsBits(producerUsage, GRALLOC1_PRODUCER_USAGE_CPU_WRITE_OFTEN))
-        bits |= AHARDWAREBUFFER_USAGE0_CPU_WRITE_OFTEN;
-    if (containsBits(consumerUsage, GRALLOC1_CONSUMER_USAGE_GPU_TEXTURE))
-        bits |= AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE;
-    if (containsBits(producerUsage, GRALLOC1_PRODUCER_USAGE_GPU_RENDER_TARGET))
-        bits |= AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT;
-    if (containsBits(consumerUsage, GRALLOC1_CONSUMER_USAGE_GPU_DATA_BUFFER))
-        bits |= AHARDWAREBUFFER_USAGE0_GPU_DATA_BUFFER;
-    if (containsBits(consumerUsage, GRALLOC1_CONSUMER_USAGE_VIDEO_ENCODER))
-        bits |= AHARDWAREBUFFER_USAGE0_VIDEO_ENCODE;
-    if (containsBits(producerUsage, GRALLOC1_PRODUCER_USAGE_PROTECTED))
-        bits |= AHARDWAREBUFFER_USAGE0_PROTECTED_CONTENT;
-    if (containsBits(producerUsage, GRALLOC1_PRODUCER_USAGE_SENSOR_DIRECT_DATA))
-        bits |= AHARDWAREBUFFER_USAGE0_SENSOR_DIRECT_DATA;
-
-    return bits;
+void AHardwareBuffer_convertFromGrallocUsageBits(uint64_t* outUsage0, uint64_t* outUsage1,
+        uint64_t producerUsage, uint64_t consumerUsage) {
+    *outUsage0 = 0;
+    *outUsage1 = 0;
+    for (const UsageMaskMapping& mapping : kUsage0ProducerMapping) {
+        if (containsBits(producerUsage, mapping.grallocMask)) {
+            *outUsage0 |= mapping.hardwareBufferMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage1ProducerMapping) {
+        if (containsBits(producerUsage, mapping.grallocMask)) {
+            *outUsage1 |= mapping.hardwareBufferMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage0ConsumerMapping) {
+        if (containsBits(consumerUsage, mapping.grallocMask)) {
+            *outUsage0 |= mapping.hardwareBufferMask;
+        }
+    }
+    for (const UsageMaskMapping& mapping : kUsage1ConsumerMapping) {
+        if (containsBits(consumerUsage, mapping.grallocMask)) {
+            *outUsage1 |= mapping.hardwareBufferMask;
+        }
+    }
 }
 
 const GraphicBuffer* AHardwareBuffer_to_GraphicBuffer(const AHardwareBuffer* buffer) {
diff --git a/libs/nativewindow/Android.bp b/libs/nativewindow/Android.bp
index 46e5d50..d0e4161 100644
--- a/libs/nativewindow/Android.bp
+++ b/libs/nativewindow/Android.bp
@@ -13,7 +13,7 @@
 // limitations under the License.
 
 ndk_headers {
-    name: "libnativewindwow_headers",
+    name: "libnativewindow_headers",
     from: "include/android",
     to: "android",
     srcs: ["include/android/*.h"],
@@ -48,3 +48,5 @@
         "libarect",
     ],
 }
+
+subdirs = ["tests"]
diff --git a/libs/nativewindow/include/android/hardware_buffer.h b/libs/nativewindow/include/android/hardware_buffer.h
index 9c08c7b..ef49995 100644
--- a/libs/nativewindow/include/android/hardware_buffer.h
+++ b/libs/nativewindow/include/android/hardware_buffer.h
@@ -97,10 +97,6 @@
     AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE      = 1ULL << 10,
     /* The buffer will be written to by the GPU */
     AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT       = 1ULL << 11,
-    /* The buffer will be read from and written to by the GPU */
-    AHARDWAREBUFFER_USAGE0_GPU_STORAGE_IMAGE      =
-            AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE |
-            AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT,
     /* The buffer will be used as a cubemap texture */
     AHARDWAREBUFFER_USAGE0_GPU_CUBEMAP            = 1ULL << 13,
     /* The buffer will be used as a shader storage or uniform buffer object*/
@@ -113,13 +109,57 @@
     AHARDWAREBUFFER_USAGE0_VIDEO_ENCODE           = 1ULL << 21,
 };
 
+/* These flags are intended only for use by device-specific graphics drivers. */
+enum {
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_19 = 1ULL << 24,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_19 = 1ULL << 25,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_18 = 1ULL << 26,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_18 = 1ULL << 27,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_17 = 1ULL << 28,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_17 = 1ULL << 29,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_16 = 1ULL << 30,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_16 = 1ULL << 31,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_15 = 1ULL << 32,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_15 = 1ULL << 33,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_14 = 1ULL << 34,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_14 = 1ULL << 35,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_13 = 1ULL << 36,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_13 = 1ULL << 37,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_12 = 1ULL << 38,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_12 = 1ULL << 39,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_11 = 1ULL << 40,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_11 = 1ULL << 41,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_10 = 1ULL << 42,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_10 = 1ULL << 43,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_9 = 1ULL << 44,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_9 = 1ULL << 45,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_8 = 1ULL << 46,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_8 = 1ULL << 47,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_7 = 1ULL << 48,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_7 = 1ULL << 49,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_6 = 1ULL << 50,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_6 = 1ULL << 51,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_5 = 1ULL << 52,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_5 = 1ULL << 53,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_4 = 1ULL << 54,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_4 = 1ULL << 55,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_3 = 1ULL << 56,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_3 = 1ULL << 57,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_2 = 1ULL << 58,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_2 = 1ULL << 59,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_1 = 1ULL << 60,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_1 = 1ULL << 61,
+    AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_0 = 1ULL << 62,
+    AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_0 = 1ULL << 63,
+};
+
 typedef struct AHardwareBuffer_Desc {
     uint32_t    width;
     uint32_t    height;
     uint32_t    layers;
+    uint32_t    format;     // One of AHARDWAREBUFFER_FORMAT_*
     uint64_t    usage0;     // Combination of AHARDWAREBUFFER_USAGE0_*
     uint64_t    usage1;     // Initialize to zero, reserved for future use
-    uint32_t    format;     // One of AHARDWAREBUFFER_FORMAT_*
 } AHardwareBuffer_Desc;
 
 typedef struct AHardwareBuffer AHardwareBuffer;
diff --git a/libs/nativewindow/include/private/android/AHardwareBufferHelpers.h b/libs/nativewindow/include/private/android/AHardwareBufferHelpers.h
index f138fa7..612ee80 100644
--- a/libs/nativewindow/include/private/android/AHardwareBufferHelpers.h
+++ b/libs/nativewindow/include/private/android/AHardwareBufferHelpers.h
@@ -18,11 +18,11 @@
 #define ANDROID_PRIVATE_NATIVE_AHARDWARE_BUFFER_HELPERS_H
 
 /*
- * This file contains utility functions related to AHardwareBuffer, mostly to convert
- * to/from HAL formats.
+ * This file contains utility functions related to AHardwareBuffer, mostly to
+ * convert to/from HAL formats.
  *
- * These are PRIVATE methods, so this file can NEVER appear in a public NDK header.
- * They are used by higher level libraries such as core/jni.
+ * These are PRIVATE methods, so this file can NEVER appear in a public NDK
+ * header. They are used by higher level libraries such as core/jni.
  */
 
 #include <stdint.h>
@@ -35,12 +35,11 @@
 
 uint32_t AHardwareBuffer_convertToPixelFormat(uint32_t format);
 
-void AHardwareBuffer_convertToGrallocUsageBits(uint64_t usage,
-        uint64_t* outProducerUsage, uint64_t* outConsumerUsage);
+void AHardwareBuffer_convertToGrallocUsageBits(uint64_t* outProducerUsage,
+    uint64_t* outConsumerUsage, uint64_t usage0, uint64_t usage1);
 
-uint64_t AHardwareBuffer_convertFromGrallocUsageBits(
-        uint64_t producerUsage, uint64_t consumerUsage);
-
+void AHardwareBuffer_convertFromGrallocUsageBits(uint64_t* outUsage0, uint64_t* outUsage1,
+    uint64_t producerUsage, uint64_t consumerUsage);
 
 class GraphicBuffer;
 const GraphicBuffer* AHardwareBuffer_to_GraphicBuffer(const AHardwareBuffer* buffer);
diff --git a/libs/nativewindow/tests/AHardwareBufferTest.cpp b/libs/nativewindow/tests/AHardwareBufferTest.cpp
new file mode 100644
index 0000000..1099043
--- /dev/null
+++ b/libs/nativewindow/tests/AHardwareBufferTest.cpp
@@ -0,0 +1,186 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "AHardwareBuffer_test"
+//#define LOG_NDEBUG 0
+
+#include <android/hardware_buffer.h>
+#include <private/android/AHardwareBufferHelpers.h>
+#include <hardware/gralloc1.h>
+
+#include <gtest/gtest.h>
+
+using namespace android;
+
+static ::testing::AssertionResult BuildHexFailureMessage(uint64_t expected,
+        uint64_t actual, const char* type) {
+    std::ostringstream ss;
+    ss << type << " 0x" << std::hex << actual
+            << " does not match expected " << type << " 0x" << std::hex
+            << expected;
+    return ::testing::AssertionFailure() << ss.str();
+}
+
+static ::testing::AssertionResult TestUsageConversion(
+        uint64_t grallocProducerUsage, uint64_t grallocConsumerUsage,
+        uint64_t hardwareBufferUsage0, uint64_t hardwareBufferUsage1) {
+    uint64_t producerUsage = 0;
+    uint64_t consumerUsage = 0;
+    uint64_t usage0 = 0;
+    uint64_t usage1 = 0;
+
+    AHardwareBuffer_convertToGrallocUsageBits(
+            &producerUsage, &consumerUsage, hardwareBufferUsage0, hardwareBufferUsage1);
+    if (producerUsage != grallocProducerUsage)
+        return BuildHexFailureMessage(grallocProducerUsage, producerUsage,
+                "producer");
+    if (consumerUsage != grallocConsumerUsage)
+        return BuildHexFailureMessage(grallocConsumerUsage, consumerUsage,
+                "consumer");
+
+    AHardwareBuffer_convertFromGrallocUsageBits(
+            &usage0, &usage1, grallocProducerUsage, grallocConsumerUsage);
+    if (usage0 != hardwareBufferUsage0)
+        return BuildHexFailureMessage(hardwareBufferUsage0, usage0, "usage0");
+    if (usage1 != hardwareBufferUsage1)
+        return BuildHexFailureMessage(hardwareBufferUsage1, usage1, "usage1");
+
+    return testing::AssertionSuccess();
+}
+
+// This is a unit test rather than going through AHardwareBuffer because not
+// all flags may be supported by the host device.
+TEST(AHardwareBufferTest, ConvertToAndFromGrallocBits) {
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_CPU_READ,
+            AHARDWAREBUFFER_USAGE0_CPU_READ, 0));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_CPU_READ_OFTEN,
+            AHARDWAREBUFFER_USAGE0_CPU_READ_OFTEN, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_CPU_WRITE, 0,
+            AHARDWAREBUFFER_USAGE0_CPU_WRITE, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_CPU_WRITE_OFTEN, 0,
+            AHARDWAREBUFFER_USAGE0_CPU_WRITE_OFTEN, 0));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_GPU_TEXTURE,
+            AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_GPU_RENDER_TARGET,
+            0, AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT, 0));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_GPU_DATA_BUFFER,
+            AHARDWAREBUFFER_USAGE0_GPU_DATA_BUFFER, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PROTECTED, 0,
+            AHARDWAREBUFFER_USAGE0_PROTECTED_CONTENT, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_SENSOR_DIRECT_DATA,
+            0, AHARDWAREBUFFER_USAGE0_SENSOR_DIRECT_DATA, 0));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_VIDEO_ENCODER,
+            AHARDWAREBUFFER_USAGE0_VIDEO_ENCODE, 0));
+
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_0, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_1, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_1));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_2, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_2));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_3, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_3));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_4, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_4));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_5, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_5));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_6, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_6));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_7, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_7));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_8, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_8));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_9, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_9));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_10, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_10));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_11, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_11));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_12, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_12));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_13, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_13));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_14, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_14));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_15, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_15));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_16, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_16));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_17, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_17));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_18, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_18));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_PRIVATE_19, 0,
+            0, AHARDWAREBUFFER_USAGE1_PRODUCER_PRIVATE_19));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_0,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_0));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_1,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_1));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_2,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_2));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_3,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_3));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_4,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_4));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_5,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_5));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_6,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_6));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_7,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_7));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_8,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_8));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_9,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_9));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_10,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_10));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_11,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_11));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_12,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_12));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_13,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_13));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_14,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_14));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_15,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_15));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_16,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_16));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_17,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_17));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_18,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_18));
+    EXPECT_TRUE(TestUsageConversion(0, GRALLOC1_CONSUMER_USAGE_PRIVATE_19,
+            0, AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_19));
+
+    // Test some more complex flag combinations.
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_CPU_WRITE,
+            GRALLOC1_CONSUMER_USAGE_CPU_READ,
+            AHARDWAREBUFFER_USAGE0_CPU_READ | AHARDWAREBUFFER_USAGE0_CPU_WRITE,
+            0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_CPU_WRITE_OFTEN, 0,
+            AHARDWAREBUFFER_USAGE0_CPU_WRITE_OFTEN, 0));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_GPU_RENDER_TARGET,
+            GRALLOC1_CONSUMER_USAGE_GPU_TEXTURE |
+                    GRALLOC1_CONSUMER_USAGE_PRIVATE_17,
+            AHARDWAREBUFFER_USAGE0_GPU_COLOR_OUTPUT |
+                    AHARDWAREBUFFER_USAGE0_GPU_SAMPLED_IMAGE,
+            AHARDWAREBUFFER_USAGE1_CONSUMER_PRIVATE_17));
+    EXPECT_TRUE(TestUsageConversion(GRALLOC1_PRODUCER_USAGE_SENSOR_DIRECT_DATA,
+            GRALLOC1_CONSUMER_USAGE_GPU_DATA_BUFFER,
+            AHARDWAREBUFFER_USAGE0_GPU_DATA_BUFFER |
+                    AHARDWAREBUFFER_USAGE0_SENSOR_DIRECT_DATA, 0));
+}
diff --git a/libs/nativewindow/tests/Android.bp b/libs/nativewindow/tests/Android.bp
new file mode 100644
index 0000000..437ab75
--- /dev/null
+++ b/libs/nativewindow/tests/Android.bp
@@ -0,0 +1,21 @@
+//
+// 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.
+//
+
+cc_test {
+    name: "AHardwareBufferTest",
+    shared_libs: ["libnativewindow"],
+    srcs: ["AHardwareBufferTest.cpp"],
+}