diff --git a/include/hardware/hwcomposer2.h b/include/hardware/hwcomposer2.h
new file mode 100644
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+++ b/include/hardware/hwcomposer2.h
@@ -0,0 +1,1900 @@
+/*
+ * 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_HARDWARE_HWCOMPOSER2_H
+#define ANDROID_HARDWARE_HWCOMPOSER2_H
+
+#include <hardware/hardware.h>
+
+#include "hwcomposer_defs.h"
+
+__BEGIN_DECLS
+
+/*
+ * Enums
+ *
+ * For most of these enums, there is an invalid value defined to be 0. This is
+ * an attempt to catch uninitialized fields, and these values should not be
+ * used.
+ */
+
+/* Display attributes queryable through getDisplayAttribute */
+typedef enum {
+    HWC2_ATTRIBUTE_INVALID = 0,
+
+    /* Dimensions in pixels */
+    HWC2_ATTRIBUTE_WIDTH = 1,
+    HWC2_ATTRIBUTE_HEIGHT = 2,
+
+    /* Vsync period in nanoseconds */
+    HWC2_ATTRIBUTE_VSYNC_PERIOD = 3,
+
+    /* Dots per thousand inches (DPI * 1000). Scaling by 1000 allows these
+     * numbers to be stored in an int32_t without losing too much precision. If
+     * the DPI for a configuration is unavailable or is considered unreliable,
+     * the device may return -1 instead */
+    HWC2_ATTRIBUTE_DPI_X = 4,
+    HWC2_ATTRIBUTE_DPI_Y = 5,
+} hwc2_attribute_t;
+
+/* Blend modes, settable per layer */
+typedef enum {
+    HWC2_BLEND_MODE_INVALID = 0,
+
+    /* colorOut = colorSrc */
+    HWC2_BLEND_MODE_NONE = 1,
+
+    /* colorOut = colorSrc + colorDst * (1 - alphaSrc) */
+    HWC2_BLEND_MODE_PREMULTIPLIED = 2,
+
+    /* colorOut = colorSrc * alphaSrc + colorDst * (1 - alphaSrc) */
+    HWC2_BLEND_MODE_COVERAGE = 3,
+} hwc2_blend_mode_t;
+
+/* See the 'Callbacks' section for more detailed descriptions of what these
+ * functions do */
+typedef enum {
+    HWC2_CALLBACK_INVALID = 0,
+    HWC2_CALLBACK_HOTPLUG = 1,
+    HWC2_CALLBACK_REFRESH = 2,
+    HWC2_CALLBACK_VSYNC = 3,
+} hwc2_callback_descriptor_t;
+
+/* Optional capabilities which may be supported by some devices. The particular
+ * set of supported capabilities for a given device may be retrieved using
+ * getCapabilities. */
+typedef enum {
+    HWC2_CAPABILITY_INVALID = 0,
+
+    /* Specifies that the device supports sideband stream layers, for which
+     * buffer content updates and other synchronization will not be provided
+     * through the usual validate/present cycle and must be handled by an
+     * external implementation-defined mechanism. Only changes to layer state
+     * (such as position, size, etc.) need to be performed through the
+     * validate/present cycle. */
+    HWC2_CAPABILITY_SIDEBAND_STREAM = 1,
+} hwc2_capability_t;
+
+/* Possible composition types for a given layer */
+typedef enum {
+    HWC2_COMPOSITION_INVALID = 0,
+
+    /* The client will composite this layer into the client target buffer
+     * (provided to the device through setClientTarget).
+     *
+     * The device must not request any composition type changes for layers of
+     * this type. */
+    HWC2_COMPOSITION_CLIENT = 1,
+
+    /* The device will handle the composition of this layer through a hardware
+     * overlay or other similar means.
+     *
+     * Upon validateDisplay, the device may request a change from this type to
+     * HWC2_COMPOSITION_CLIENT. */
+    HWC2_COMPOSITION_DEVICE = 2,
+
+    /* The device will render this layer using the color set through
+     * setLayerColor. If this functionality is not supported on a layer that the
+     * client sets to HWC2_COMPOSITION_SOLID_COLOR, the device must request that
+     * the composition type of that layer is changed to HWC2_COMPOSITION_CLIENT
+     * upon the next call to validateDisplay.
+     *
+     * Upon validateDisplay, the device may request a change from this type to
+     * HWC2_COMPOSITION_CLIENT. */
+    HWC2_COMPOSITION_SOLID_COLOR = 3,
+
+    /* Similar to DEVICE, but the position of this layer may also be set
+     * asynchronously through setCursorPosition. If this functionality is not
+     * supported on a layer that the client sets to HWC2_COMPOSITION_CURSOR, the
+     * device must request that the composition type of that layer is changed to
+     * HWC2_COMPOSITION_CLIENT upon the next call to validateDisplay.
+     *
+     * Upon validateDisplay, the device may request a change from this type to
+     * either HWC2_COMPOSITION_DEVICE or HWC2_COMPOSITION_CLIENT. Changing to
+     * HWC2_COMPOSITION_DEVICE will prevent the use of setCursorPosition but
+     * still permit the device to composite the layer. */
+    HWC2_COMPOSITION_CURSOR = 4,
+
+    /* The device will handle the composition of this layer, as well as its
+     * buffer updates and content synchronization. Only supported on devices
+     * which provide HWC2_CAPABILITY_SIDEBAND_STREAM.
+     *
+     * Upon validateDisplay, the device may request a change from this type to
+     * either HWC2_COMPOSITION_DEVICE or HWC2_COMPOSITION_CLIENT, but it is
+     * unlikely that content will display correctly in these cases. */
+    HWC2_COMPOSITION_SIDEBAND = 5,
+} hwc2_composition_t;
+
+/* Possible connection options from the hotplug callback */
+typedef enum {
+    HWC2_CONNECTION_INVALID = 0,
+
+    /* The display has been connected */
+    HWC2_CONNECTION_CONNECTED = 1,
+
+    /* The display has been disconnected */
+    HWC2_CONNECTION_DISCONNECTED = 2,
+} hwc2_connection_t;
+
+/* Display requests returned by getDisplayRequests */
+typedef enum {
+    /* Instructs the client to provide a new client target buffer, even if no
+     * layers are marked for client composition. */
+    HWC2_DISPLAY_REQUEST_FLIP_CLIENT_TARGET = 1 << 0,
+
+    /* Instructs the client to write the result of client composition directly
+     * into the virtual display output buffer. If any of the layers are not
+     * marked as HWC2_COMPOSITION_CLIENT or the given display is not a virtual
+     * display, this request has no effect. */
+    HWC2_DISPLAY_REQUEST_WRITE_CLIENT_TARGET_TO_OUTPUT = 1 << 1,
+} hwc2_display_request_t;
+
+/* Display types returned by getDisplayType */
+typedef enum {
+    HWC2_DISPLAY_TYPE_INVALID = 0,
+
+    /* All physical displays, including both internal displays and hotpluggable
+     * external displays */
+    HWC2_DISPLAY_TYPE_PHYSICAL = 1,
+
+    /* Virtual displays created by createVirtualDisplay */
+    HWC2_DISPLAY_TYPE_VIRTUAL = 2,
+} hwc2_display_type_t;
+
+/* Return codes from all functions */
+typedef enum {
+    HWC2_ERROR_NONE = 0,
+    HWC2_ERROR_BAD_CONFIG,
+    HWC2_ERROR_BAD_DISPLAY,
+    HWC2_ERROR_BAD_LAYER,
+    HWC2_ERROR_BAD_PARAMETER,
+    HWC2_ERROR_HAS_CHANGES,
+    HWC2_ERROR_NO_RESOURCES,
+    HWC2_ERROR_NOT_VALIDATED,
+    HWC2_ERROR_UNSUPPORTED,
+} hwc2_error_t;
+
+/* Function descriptors for use with getFunction */
+typedef enum {
+    HWC2_FUNCTION_INVALID = 0,
+    HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES,
+    HWC2_FUNCTION_CREATE_LAYER,
+    HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY,
+    HWC2_FUNCTION_DESTROY_LAYER,
+    HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY,
+    HWC2_FUNCTION_DUMP,
+    HWC2_FUNCTION_GET_ACTIVE_CONFIG,
+    HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES,
+    HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT,
+    HWC2_FUNCTION_GET_COLOR_MODES,
+    HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE,
+    HWC2_FUNCTION_GET_DISPLAY_CONFIGS,
+    HWC2_FUNCTION_GET_DISPLAY_NAME,
+    HWC2_FUNCTION_GET_DISPLAY_REQUESTS,
+    HWC2_FUNCTION_GET_DISPLAY_TYPE,
+    HWC2_FUNCTION_GET_DOZE_SUPPORT,
+    HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT,
+    HWC2_FUNCTION_GET_RELEASE_FENCES,
+    HWC2_FUNCTION_PRESENT_DISPLAY,
+    HWC2_FUNCTION_REGISTER_CALLBACK,
+    HWC2_FUNCTION_SET_ACTIVE_CONFIG,
+    HWC2_FUNCTION_SET_CLIENT_TARGET,
+    HWC2_FUNCTION_SET_COLOR_MODE,
+    HWC2_FUNCTION_SET_COLOR_TRANSFORM,
+    HWC2_FUNCTION_SET_CURSOR_POSITION,
+    HWC2_FUNCTION_SET_LAYER_BLEND_MODE,
+    HWC2_FUNCTION_SET_LAYER_BUFFER,
+    HWC2_FUNCTION_SET_LAYER_COLOR,
+    HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE,
+    HWC2_FUNCTION_SET_LAYER_DATASPACE,
+    HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME,
+    HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA,
+    HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM,
+    HWC2_FUNCTION_SET_LAYER_SOURCE_CROP,
+    HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE,
+    HWC2_FUNCTION_SET_LAYER_TRANSFORM,
+    HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION,
+    HWC2_FUNCTION_SET_LAYER_Z_ORDER,
+    HWC2_FUNCTION_SET_OUTPUT_BUFFER,
+    HWC2_FUNCTION_SET_POWER_MODE,
+    HWC2_FUNCTION_SET_VSYNC_ENABLED,
+    HWC2_FUNCTION_VALIDATE_DISPLAY,
+} hwc2_function_descriptor_t;
+
+/* Layer requests returned from getDisplayRequests. */
+typedef enum {
+    /* The client should clear its target with transparent pixels where this
+     * layer would be. The client may ignore this request if the layer must be
+     * blended. */
+    HWC2_LAYER_REQUEST_CLEAR_CLIENT_TARGET = 1 << 0,
+} hwc2_layer_request_t;
+
+/* Power modes for use with setPowerMode */
+typedef enum {
+    /* The display is fully off (blanked) */
+    HWC2_POWER_MODE_OFF = 0,
+
+    /* These are optional low power modes. getDozeSupport may be called to
+     * determine whether a given display supports these modes. */
+
+    /* The display is turned on and configured in a low power state that is
+     * suitable for presenting ambient information to the user, possibly with
+     * lower fidelity than HWC2_POWER_MODE_ON, but with greater efficiency. */
+    HWC2_POWER_MODE_DOZE = 1,
+
+    /* The display is configured as in HWC2_POWER_MODE_DOZE but may stop
+     * applying display updates from the client. This is effectively a hint to
+     * the device that drawing to the display has been suspended and that the
+     * the device should remain on in a low power state and continue displaying
+     * its current contents indefinitely until the power mode changes.
+     *
+     * This mode may also be used as a signal to enable hardware-based doze
+     * functionality. In this case, the device is free to take over the display
+     * and manage it autonomously to implement a low power always-on display. */
+    HWC2_POWER_MODE_DOZE_SUSPEND = 3,
+
+    /* The display is fully on */
+    HWC2_POWER_MODE_ON = 2,
+} hwc2_power_mode_t;
+
+/* Vsync values passed to setVsyncEnabled */
+typedef enum {
+    HWC2_VSYNC_INVALID = 0,
+
+    /* Enable vsync */
+    HWC2_VSYNC_ENABLE = 1,
+
+    /* Disable vsync */
+    HWC2_VSYNC_DISABLE = 2,
+} hwc2_vsync_t;
+
+/*
+ * Stringification Functions
+ */
+
+#ifdef HWC2_INCLUDE_STRINGIFICATION
+
+static inline const char* getAttributeName(hwc2_attribute_t attribute) {
+    switch (attribute) {
+        case HWC2_ATTRIBUTE_INVALID: return "Invalid";
+        case HWC2_ATTRIBUTE_WIDTH: return "Width";
+        case HWC2_ATTRIBUTE_HEIGHT: return "Height";
+        case HWC2_ATTRIBUTE_VSYNC_PERIOD: return "VsyncPeriod";
+        case HWC2_ATTRIBUTE_DPI_X: return "DpiX";
+        case HWC2_ATTRIBUTE_DPI_Y: return "DpiY";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getBlendModeName(hwc2_blend_mode_t mode) {
+    switch (mode) {
+        case HWC2_BLEND_MODE_INVALID: return "Invalid";
+        case HWC2_BLEND_MODE_NONE: return "None";
+        case HWC2_BLEND_MODE_PREMULTIPLIED: return "Premultiplied";
+        case HWC2_BLEND_MODE_COVERAGE: return "Coverage";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getCallbackDescriptorName(
+        hwc2_callback_descriptor_t desc) {
+    switch (desc) {
+        case HWC2_CALLBACK_INVALID: return "Invalid";
+        case HWC2_CALLBACK_HOTPLUG: return "Hotplug";
+        case HWC2_CALLBACK_REFRESH: return "Refresh";
+        case HWC2_CALLBACK_VSYNC: return "Vsync";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getCapabilityName(hwc2_capability_t capability) {
+    switch (capability) {
+        case HWC2_CAPABILITY_INVALID: return "Invalid";
+        case HWC2_CAPABILITY_SIDEBAND_STREAM: return "SidebandStream";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getCompositionName(hwc2_composition_t composition) {
+    switch (composition) {
+        case HWC2_COMPOSITION_INVALID: return "Invalid";
+        case HWC2_COMPOSITION_CLIENT: return "Client";
+        case HWC2_COMPOSITION_DEVICE: return "Device";
+        case HWC2_COMPOSITION_SOLID_COLOR: return "SolidColor";
+        case HWC2_COMPOSITION_CURSOR: return "Cursor";
+        case HWC2_COMPOSITION_SIDEBAND: return "Sideband";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getConnectionName(hwc2_connection_t connection) {
+    switch (connection) {
+        case HWC2_CONNECTION_INVALID: return "Invalid";
+        case HWC2_CONNECTION_CONNECTED: return "Connected";
+        case HWC2_CONNECTION_DISCONNECTED: return "Disconnected";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getDisplayRequestName(
+        hwc2_display_request_t request) {
+    switch (request) {
+        case 0: return "None";
+        case HWC2_DISPLAY_REQUEST_FLIP_CLIENT_TARGET: return "FlipClientTarget";
+        case HWC2_DISPLAY_REQUEST_WRITE_CLIENT_TARGET_TO_OUTPUT:
+            return "WriteClientTargetToOutput";
+        case HWC2_DISPLAY_REQUEST_FLIP_CLIENT_TARGET |
+                HWC2_DISPLAY_REQUEST_WRITE_CLIENT_TARGET_TO_OUTPUT:
+            return "FlipClientTarget|WriteClientTargetToOutput";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getDisplayTypeName(hwc2_display_type_t type) {
+    switch (type) {
+        case HWC2_DISPLAY_TYPE_INVALID: return "Invalid";
+        case HWC2_DISPLAY_TYPE_PHYSICAL: return "Physical";
+        case HWC2_DISPLAY_TYPE_VIRTUAL: return "Virtual";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getErrorName(hwc2_error_t error) {
+    switch (error) {
+        case HWC2_ERROR_NONE: return "None";
+        case HWC2_ERROR_BAD_CONFIG: return "BadConfig";
+        case HWC2_ERROR_BAD_DISPLAY: return "BadDisplay";
+        case HWC2_ERROR_BAD_LAYER: return "BadLayer";
+        case HWC2_ERROR_BAD_PARAMETER: return "BadParameter";
+        case HWC2_ERROR_HAS_CHANGES: return "HasChanges";
+        case HWC2_ERROR_NO_RESOURCES: return "NoResources";
+        case HWC2_ERROR_NOT_VALIDATED: return "NotValidated";
+        case HWC2_ERROR_UNSUPPORTED: return "Unsupported";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getFunctionDescriptorName(
+        hwc2_function_descriptor_t desc) {
+    switch (desc) {
+        case HWC2_FUNCTION_INVALID: return "Invalid";
+        case HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES:
+            return "AcceptDisplayChanges";
+        case HWC2_FUNCTION_CREATE_LAYER: return "CreateLayer";
+        case HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY:
+            return "CreateVirtualDisplay";
+        case HWC2_FUNCTION_DESTROY_LAYER: return "DestroyLayer";
+        case HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY:
+            return "DestroyVirtualDisplay";
+        case HWC2_FUNCTION_DUMP: return "Dump";
+        case HWC2_FUNCTION_GET_ACTIVE_CONFIG: return "GetActiveConfig";
+        case HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES:
+            return "GetChangedCompositionTypes";
+        case HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT:
+            return "GetClientTargetSupport";
+        case HWC2_FUNCTION_GET_COLOR_MODES: return "GetColorModes";
+        case HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE: return "GetDisplayAttribute";
+        case HWC2_FUNCTION_GET_DISPLAY_CONFIGS: return "GetDisplayConfigs";
+        case HWC2_FUNCTION_GET_DISPLAY_NAME: return "GetDisplayName";
+        case HWC2_FUNCTION_GET_DISPLAY_REQUESTS: return "GetDisplayRequests";
+        case HWC2_FUNCTION_GET_DISPLAY_TYPE: return "GetDisplayType";
+        case HWC2_FUNCTION_GET_DOZE_SUPPORT: return "GetDozeSupport";
+        case HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT:
+            return "GetMaxVirtualDisplayCount";
+        case HWC2_FUNCTION_GET_RELEASE_FENCES: return "GetReleaseFences";
+        case HWC2_FUNCTION_PRESENT_DISPLAY: return "PresentDisplay";
+        case HWC2_FUNCTION_REGISTER_CALLBACK: return "RegisterCallback";
+        case HWC2_FUNCTION_SET_ACTIVE_CONFIG: return "SetActiveConfig";
+        case HWC2_FUNCTION_SET_CLIENT_TARGET: return "SetClientTarget";
+        case HWC2_FUNCTION_SET_COLOR_MODE: return "SetColorMode";
+        case HWC2_FUNCTION_SET_COLOR_TRANSFORM: return "SetColorTransform";
+        case HWC2_FUNCTION_SET_CURSOR_POSITION: return "SetCursorPosition";
+        case HWC2_FUNCTION_SET_LAYER_BLEND_MODE: return "SetLayerBlendMode";
+        case HWC2_FUNCTION_SET_LAYER_BUFFER: return "SetLayerBuffer";
+        case HWC2_FUNCTION_SET_LAYER_COLOR: return "SetLayerColor";
+        case HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE:
+            return "SetLayerCompositionType";
+        case HWC2_FUNCTION_SET_LAYER_DATASPACE: return "SetLayerDataspace";
+        case HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME:
+            return "SetLayerDisplayFrame";
+        case HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA: return "SetLayerPlaneAlpha";
+        case HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM:
+            return "SetLayerSidebandStream";
+        case HWC2_FUNCTION_SET_LAYER_SOURCE_CROP: return "SetLayerSourceCrop";
+        case HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE:
+            return "SetLayerSurfaceDamage";
+        case HWC2_FUNCTION_SET_LAYER_TRANSFORM: return "SetLayerTransform";
+        case HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION:
+            return "SetLayerVisibleRegion";
+        case HWC2_FUNCTION_SET_LAYER_Z_ORDER: return "SetLayerZOrder";
+        case HWC2_FUNCTION_SET_OUTPUT_BUFFER: return "SetOutputBuffer";
+        case HWC2_FUNCTION_SET_POWER_MODE: return "SetPowerMode";
+        case HWC2_FUNCTION_SET_VSYNC_ENABLED: return "SetVsyncEnabled";
+        case HWC2_FUNCTION_VALIDATE_DISPLAY: return "ValidateDisplay";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getLayerRequestName(hwc2_layer_request_t request) {
+    switch (request) {
+        case 0: return "None";
+        case HWC2_LAYER_REQUEST_CLEAR_CLIENT_TARGET: return "ClearClientTarget";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getPowerModeName(hwc2_power_mode_t mode) {
+    switch (mode) {
+        case HWC2_POWER_MODE_OFF: return "Off";
+        case HWC2_POWER_MODE_DOZE_SUSPEND: return "DozeSuspend";
+        case HWC2_POWER_MODE_DOZE: return "Doze";
+        case HWC2_POWER_MODE_ON: return "On";
+        default: return "Unknown";
+    }
+}
+
+static inline const char* getTransformName(hwc_transform_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 "Unknown";
+    }
+}
+
+static inline const char* getVsyncName(hwc2_vsync_t vsync) {
+    switch (vsync) {
+        case HWC2_VSYNC_INVALID: return "Invalid";
+        case HWC2_VSYNC_ENABLE: return "Enable";
+        case HWC2_VSYNC_DISABLE: return "Disable";
+        default: return "Unknown";
+    }
+}
+
+#define TO_STRING(E, T, printer) \
+    inline std::string to_string(E value) { return printer(value); } \
+    inline std::string to_string(T value) { return to_string(static_cast<E>(value)); }
+#else // !HWC2_INCLUDE_STRINGIFICATION
+#define TO_STRING(name, printer)
+#endif // HWC2_INCLUDE_STRINGIFICATION
+
+/*
+ * C++11 features
+ */
+
+#ifdef HWC2_USE_CPP11
+__END_DECLS
+
+#ifdef HWC2_INCLUDE_STRINGIFICATION
+#include <string>
+#endif
+
+namespace HWC2 {
+
+enum class Attribute : int32_t {
+    Invalid = HWC2_ATTRIBUTE_INVALID,
+    Width = HWC2_ATTRIBUTE_WIDTH,
+    Height = HWC2_ATTRIBUTE_HEIGHT,
+    VsyncPeriod = HWC2_ATTRIBUTE_VSYNC_PERIOD,
+    DpiX = HWC2_ATTRIBUTE_DPI_X,
+    DpiY = HWC2_ATTRIBUTE_DPI_Y,
+};
+TO_STRING(hwc2_attribute_t, Attribute, getAttributeName)
+
+enum class BlendMode : int32_t {
+    Invalid = HWC2_BLEND_MODE_INVALID,
+    None = HWC2_BLEND_MODE_NONE,
+    Premultiplied = HWC2_BLEND_MODE_PREMULTIPLIED,
+    Coverage = HWC2_BLEND_MODE_COVERAGE,
+};
+TO_STRING(hwc2_blend_mode_t, BlendMode, getBlendModeName)
+
+enum class Callback : int32_t {
+    Invalid = HWC2_CALLBACK_INVALID,
+    Hotplug = HWC2_CALLBACK_HOTPLUG,
+    Refresh = HWC2_CALLBACK_REFRESH,
+    Vsync = HWC2_CALLBACK_VSYNC,
+};
+TO_STRING(hwc2_callback_descriptor_t, Callback, getCallbackDescriptorName)
+
+enum class Capability : int32_t {
+    Invalid = HWC2_CAPABILITY_INVALID,
+    SidebandStream = HWC2_CAPABILITY_SIDEBAND_STREAM,
+};
+TO_STRING(hwc2_capability_t, Capability, getCapabilityName)
+
+enum class Composition : int32_t {
+    Invalid = HWC2_COMPOSITION_INVALID,
+    Client = HWC2_COMPOSITION_CLIENT,
+    Device = HWC2_COMPOSITION_DEVICE,
+    SolidColor = HWC2_COMPOSITION_SOLID_COLOR,
+    Cursor = HWC2_COMPOSITION_CURSOR,
+    Sideband = HWC2_COMPOSITION_SIDEBAND,
+};
+TO_STRING(hwc2_composition_t, Composition, getCompositionName)
+
+enum class Connection : int32_t {
+    Invalid = HWC2_CONNECTION_INVALID,
+    Connected = HWC2_CONNECTION_CONNECTED,
+    Disconnected = HWC2_CONNECTION_DISCONNECTED,
+};
+TO_STRING(hwc2_connection_t, Connection, getConnectionName)
+
+enum class DisplayRequest : int32_t {
+    FlipClientTarget = HWC2_DISPLAY_REQUEST_FLIP_CLIENT_TARGET,
+    WriteClientTargetToOutput =
+        HWC2_DISPLAY_REQUEST_WRITE_CLIENT_TARGET_TO_OUTPUT,
+};
+TO_STRING(hwc2_display_request_t, DisplayRequest, getDisplayRequestName)
+
+enum class DisplayType : int32_t {
+    Invalid = HWC2_DISPLAY_TYPE_INVALID,
+    Physical = HWC2_DISPLAY_TYPE_PHYSICAL,
+    Virtual = HWC2_DISPLAY_TYPE_VIRTUAL,
+};
+TO_STRING(hwc2_display_type_t, DisplayType, getDisplayTypeName)
+
+enum class Error : int32_t {
+    None = HWC2_ERROR_NONE,
+    BadConfig = HWC2_ERROR_BAD_CONFIG,
+    BadDisplay = HWC2_ERROR_BAD_DISPLAY,
+    BadLayer = HWC2_ERROR_BAD_LAYER,
+    BadParameter = HWC2_ERROR_BAD_PARAMETER,
+    HasChanges = HWC2_ERROR_HAS_CHANGES,
+    NoResources = HWC2_ERROR_NO_RESOURCES,
+    NotValidated = HWC2_ERROR_NOT_VALIDATED,
+    Unsupported = HWC2_ERROR_UNSUPPORTED,
+};
+TO_STRING(hwc2_error_t, Error, getErrorName)
+
+enum class FunctionDescriptor : int32_t {
+    Invalid = HWC2_FUNCTION_INVALID,
+    AcceptDisplayChanges = HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES,
+    CreateLayer = HWC2_FUNCTION_CREATE_LAYER,
+    CreateVirtualDisplay = HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY,
+    DestroyLayer = HWC2_FUNCTION_DESTROY_LAYER,
+    DestroyVirtualDisplay = HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY,
+    Dump = HWC2_FUNCTION_DUMP,
+    GetActiveConfig = HWC2_FUNCTION_GET_ACTIVE_CONFIG,
+    GetChangedCompositionTypes = HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES,
+    GetClientTargetSupport = HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT,
+    GetColorModes = HWC2_FUNCTION_GET_COLOR_MODES,
+    GetDisplayAttribute = HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE,
+    GetDisplayConfigs = HWC2_FUNCTION_GET_DISPLAY_CONFIGS,
+    GetDisplayName = HWC2_FUNCTION_GET_DISPLAY_NAME,
+    GetDisplayRequests = HWC2_FUNCTION_GET_DISPLAY_REQUESTS,
+    GetDisplayType = HWC2_FUNCTION_GET_DISPLAY_TYPE,
+    GetDozeSupport = HWC2_FUNCTION_GET_DOZE_SUPPORT,
+    GetMaxVirtualDisplayCount = HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT,
+    GetReleaseFences = HWC2_FUNCTION_GET_RELEASE_FENCES,
+    PresentDisplay = HWC2_FUNCTION_PRESENT_DISPLAY,
+    RegisterCallback = HWC2_FUNCTION_REGISTER_CALLBACK,
+    SetActiveConfig = HWC2_FUNCTION_SET_ACTIVE_CONFIG,
+    SetClientTarget = HWC2_FUNCTION_SET_CLIENT_TARGET,
+    SetColorMode = HWC2_FUNCTION_SET_COLOR_MODE,
+    SetColorTransform = HWC2_FUNCTION_SET_COLOR_TRANSFORM,
+    SetCursorPosition = HWC2_FUNCTION_SET_CURSOR_POSITION,
+    SetLayerBlendMode = HWC2_FUNCTION_SET_LAYER_BLEND_MODE,
+    SetLayerBuffer = HWC2_FUNCTION_SET_LAYER_BUFFER,
+    SetLayerColor = HWC2_FUNCTION_SET_LAYER_COLOR,
+    SetLayerCompositionType = HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE,
+    SetLayerDataspace = HWC2_FUNCTION_SET_LAYER_DATASPACE,
+    SetLayerDisplayFrame = HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME,
+    SetLayerPlaneAlpha = HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA,
+    SetLayerSidebandStream = HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM,
+    SetLayerSourceCrop = HWC2_FUNCTION_SET_LAYER_SOURCE_CROP,
+    SetLayerSurfaceDamage = HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE,
+    SetLayerTransform = HWC2_FUNCTION_SET_LAYER_TRANSFORM,
+    SetLayerVisibleRegion = HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION,
+    SetLayerZOrder = HWC2_FUNCTION_SET_LAYER_Z_ORDER,
+    SetOutputBuffer = HWC2_FUNCTION_SET_OUTPUT_BUFFER,
+    SetPowerMode = HWC2_FUNCTION_SET_POWER_MODE,
+    SetVsyncEnabled = HWC2_FUNCTION_SET_VSYNC_ENABLED,
+    ValidateDisplay = HWC2_FUNCTION_VALIDATE_DISPLAY,
+};
+TO_STRING(hwc2_function_descriptor_t, FunctionDescriptor,
+        getFunctionDescriptorName)
+
+enum class LayerRequest : int32_t {
+    ClearClientTarget = HWC2_LAYER_REQUEST_CLEAR_CLIENT_TARGET,
+};
+TO_STRING(hwc2_layer_request_t, LayerRequest, getLayerRequestName)
+
+enum class PowerMode : int32_t {
+    Off = HWC2_POWER_MODE_OFF,
+    DozeSuspend = HWC2_POWER_MODE_DOZE_SUSPEND,
+    Doze = HWC2_POWER_MODE_DOZE,
+    On = HWC2_POWER_MODE_ON,
+};
+TO_STRING(hwc2_power_mode_t, PowerMode, getPowerModeName)
+
+enum class Transform : int32_t {
+    None = 0,
+    FlipH = HWC_TRANSFORM_FLIP_H,
+    FlipV = HWC_TRANSFORM_FLIP_V,
+    Rotate90 = HWC_TRANSFORM_ROT_90,
+    Rotate180 = HWC_TRANSFORM_ROT_180,
+    Rotate270 = HWC_TRANSFORM_ROT_270,
+    FlipHRotate90 = HWC_TRANSFORM_FLIP_H_ROT_90,
+    FlipVRotate90 = HWC_TRANSFORM_FLIP_V_ROT_90,
+};
+TO_STRING(hwc_transform_t, Transform, getTransformName)
+
+enum class Vsync : int32_t {
+    Invalid = HWC2_VSYNC_INVALID,
+    Enable = HWC2_VSYNC_ENABLE,
+    Disable = HWC2_VSYNC_DISABLE,
+};
+TO_STRING(hwc2_vsync_t, Vsync, getVsyncName)
+
+} // namespace HWC2
+
+__BEGIN_DECLS
+#endif // HWC2_USE_CPP11
+
+/*
+ * Typedefs
+ */
+
+typedef void (*hwc2_function_pointer_t)();
+
+typedef void* hwc2_callback_data_t;
+typedef uint32_t hwc2_config_t;
+typedef uint64_t hwc2_display_t;
+typedef uint64_t hwc2_layer_t;
+
+/*
+ * Device Struct
+ */
+
+typedef struct hwc2_device {
+    /* Must be the first member of this struct, since a pointer to this struct
+     * will be generated by casting from a hw_device_t* */
+    struct hw_device_t common;
+
+    /* getCapabilities(..., outCount, outCapabilities)
+     *
+     * Provides a list of capabilities (described in the definition of
+     * hwc2_capability_t above) supported by this device. This list must
+     * not change after the device has been loaded.
+     *
+     * Parameters:
+     *   outCount - if outCapabilities was NULL, the number of capabilities
+     *       which would have been returned; if outCapabilities was not NULL,
+     *       the number of capabilities returned, which must not exceed the
+     *       value stored in outCount prior to the call
+     *   outCapabilities - a list of capabilities supported by this device; may
+     *       be NULL, in which case this function must write into outCount the
+     *       number of capabilities which would have been written into
+     *       outCapabilities
+     */
+    void (*getCapabilities)(struct hwc2_device* device, uint32_t* outCount,
+            int32_t* /*hwc2_capability_t*/ outCapabilities);
+
+    /* getFunction(..., descriptor)
+     *
+     * Returns a function pointer which implements the requested description.
+     *
+     * Parameters:
+     *   descriptor - the function to return
+     *
+     * Returns either a function pointer implementing the requested descriptor
+     *   or NULL if the described function is not supported by this device.
+     */
+    hwc2_function_pointer_t (*getFunction)(struct hwc2_device* device,
+            int32_t /*hwc2_function_descriptor_t*/ descriptor);
+} hwc2_device_t;
+
+static inline int hwc2_open(const struct hw_module_t* module,
+        hwc2_device_t** device) {
+    return module->methods->open(module, HWC_HARDWARE_COMPOSER,
+            (struct hw_device_t**) device);
+}
+
+static inline int hwc2_close(hwc2_device_t* device) {
+    return device->common.close(&device->common);
+}
+
+/*
+ * Callbacks
+ *
+ * All of these callbacks take as their first parameter the callbackData which
+ * was provided at the time of callback registration, so this parameter is
+ * omitted from the described parameter lists.
+ */
+
+/* hotplug(..., display, connected)
+ * Descriptor: HWC2_CALLBACK_HOTPLUG
+ * Will be provided to all HWC2 devices
+ *
+ * Notifies the client that the given display has either been connected or
+ * disconnected. Every active display (even a built-in physical display) must
+ * trigger at least one hotplug notification, even if it only occurs immediately
+ * after callback registration.
+ *
+ * The client may call back into the device on the same thread to query display
+ * properties (such as width, height, and vsync period), and other threads may
+ * call into the device while the callback is in progress. The device must
+ * serialize calls to this callback such that only one thread is calling it at a
+ * time.
+ *
+ * Displays which have been connected are assumed to be in HWC2_POWER_MODE_OFF,
+ * and the vsync callback should not be called for a display until vsync has
+ * been enabled with setVsyncEnabled.
+ *
+ * Parameters:
+ *   display - the display which has been hotplugged
+ *   connected - whether the display has been connected or disconnected
+ */
+typedef void (*HWC2_PFN_HOTPLUG)(hwc2_callback_data_t callbackData,
+        hwc2_display_t display, int32_t /*hwc2_connection_t*/ connected);
+
+/* refresh(..., display)
+ * Descriptor: HWC2_CALLBACK_REFRESH
+ * Will be provided to all HWC2 devices
+ *
+ * Notifies the client to trigger a screen refresh. This forces all layer state
+ * for this display to be resent, and the display to be validated and presented,
+ * even if there have been no changes.
+ *
+ * This refresh will occur some time after the callback is initiated, but not
+ * necessarily before it returns. This thread, however, is guaranteed not to
+ * call back into the device, thus it is safe to trigger this callback from
+ * other functions which call into the device.
+ *
+ * Parameters:
+ *   display - the display to refresh
+ */
+typedef void (*HWC2_PFN_REFRESH)(hwc2_callback_data_t callbackData,
+        hwc2_display_t display);
+
+/* vsync(..., display, timestamp)
+ * Descriptor: HWC2_CALLBACK_VSYNC
+ * Will be provided to all HWC2 devices
+ *
+ * Notifies the client that a vsync event has occurred. This callback must
+ * only be triggered when vsync is enabled for this display (through
+ * setVsyncEnabled).
+ *
+ * This callback should be triggered from a thread of at least
+ * HAL_PRIORITY_URGENT_DISPLAY with as little latency as possible, typically
+ * less than 0.5 ms. This thread is guaranteed not to call back into the device.
+ *
+ * Parameters:
+ *   display - the display which has received a vsync event
+ *   timestamp - the CLOCK_MONOTONIC time at which the vsync event occurred, in
+ *       nanoseconds
+ */
+typedef void (*HWC2_PFN_VSYNC)(hwc2_callback_data_t callbackData,
+        hwc2_display_t display, int64_t timestamp);
+
+/*
+ * Device Functions
+ *
+ * All of these functions take as their first parameter a device pointer, so
+ * this parameter is omitted from the described parameter lists.
+ */
+
+/* createVirtualDisplay(..., width, height, outDisplay)
+ * Descriptor: HWC2_FUNCTION_CREATE_VIRTUAL_DISPLAY
+ * Must be provided by all HWC2 devices
+ *
+ * Creates a new virtual display with the given width and height. The display
+ * will be assumed to be on from the time the first frame is presented until the
+ * display is destroyed.
+ *
+ * Parameters:
+ *   width - width in pixels
+ *   height - height in pixels
+ *   outDisplay - the newly-created virtual display; pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_UNSUPPORTED - the width or height is too large for the device to
+ *       be able to create a virtual display
+ *   HWC2_ERROR_NO_RESOURCES - the device is unable to create a new virtual
+ *       display at this time
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_CREATE_VIRTUAL_DISPLAY)(
+        hwc2_device_t* device, uint32_t width, uint32_t height,
+        hwc2_display_t* outDisplay);
+
+/* destroyVirtualDisplay(..., display)
+ * Descriptor: HWC2_FUNCTION_DESTROY_VIRTUAL_DISPLAY
+ * Must be provided by all HWC2 devices
+ *
+ * Destroys a virtual display. After this call all resources consumed by this
+ * display may be freed by the device and any operations performed on this
+ * display should fail.
+ *
+ * Parameters:
+ *   display - the virtual display to destroy
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - the display handle which was passed in does not
+ *       refer to a virtual display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_DESTROY_VIRTUAL_DISPLAY)(
+        hwc2_device_t* device, hwc2_display_t display);
+
+/* dump(..., outSize, outBuffer)
+ * Descriptor: HWC2_FUNCTION_DUMP
+ * Must be provided by all HWC2 devices
+ *
+ * Retrieves implementation-defined debug information, which will be displayed
+ * during, for example, `dumpsys SurfaceFlinger`.
+ *
+ * If called with outBuffer == NULL, the device should store a copy of the
+ * desired output and return its length in bytes in outSize. If the device
+ * already has a stored copy, that copy should be purged and replaced with a
+ * fresh copy.
+ *
+ * If called with outBuffer != NULL, the device should copy its stored version
+ * of the output into outBuffer and store how many bytes of data it copied into
+ * outSize. Prior to this call, the client will have populated outSize with the
+ * maximum number of bytes outBuffer can hold. The device must not write more
+ * than this amount into outBuffer. If the device does not currently have a
+ * stored copy, then it should return 0 in outSize.
+ *
+ * Any data written into outBuffer need not be null-terminated.
+ *
+ * Parameters:
+ *   outSize - if outBuffer was NULL, the number of bytes needed to copy the
+ *       device's stored output; if outBuffer was not NULL, the number of bytes
+ *       written into it, which must not exceed the value stored in outSize
+ *       prior to the call; pointer will be non-NULL
+ *   outBuffer - the buffer to write the dump output into; may be NULL as
+ *       described above; data written into this buffer need not be
+ *       null-terminated
+ */
+typedef void (*HWC2_PFN_DUMP)(hwc2_device_t* device, uint32_t* outSize,
+        char* outBuffer);
+
+/* getMaxVirtualDisplayCount(...)
+ * Descriptor: HWC2_FUNCTION_GET_MAX_VIRTUAL_DISPLAY_COUNT
+ * Must be provided by all HWC2 devices
+ *
+ * Returns the maximum number of virtual displays supported by this device
+ * (which may be 0). The client will not attempt to create more than this many
+ * virtual displays on this device. This number must not change for the lifetime
+ * of the device.
+ */
+typedef uint32_t (*HWC2_PFN_GET_MAX_VIRTUAL_DISPLAY_COUNT)(
+        hwc2_device_t* device);
+
+/* registerCallback(..., descriptor, callbackData, pointer)
+ * Descriptor: HWC2_FUNCTION_REGISTER_CALLBACK
+ * Must be provided by all HWC2 devices
+ *
+ * Provides a callback for the device to call. All callbacks take a callbackData
+ * item as the first parameter, so this value should be stored with the callback
+ * for later use. The callbackData may differ from one callback to another. If
+ * this function is called multiple times with the same descriptor, later
+ * callbacks replace earlier ones.
+ *
+ * Parameters:
+ *   descriptor - which callback should be set
+ *   callBackdata - opaque data which must be passed back through the callback
+ *   pointer - a non-NULL function pointer corresponding to the descriptor
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_PARAMETER - descriptor was invalid
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_REGISTER_CALLBACK)(
+        hwc2_device_t* device,
+        int32_t /*hwc2_callback_descriptor_t*/ descriptor,
+        hwc2_callback_data_t callbackData, hwc2_function_pointer_t pointer);
+
+/*
+ * Display Functions
+ *
+ * All of these functions take as their first two parameters a device pointer
+ * and a display handle, so these parameters are omitted from the described
+ * parameter lists.
+ */
+
+/* acceptDisplayChanges(...)
+ * Descriptor: HWC2_FUNCTION_ACCEPT_DISPLAY_CHANGES
+ * Must be provided by all HWC2 devices
+ *
+ * Accepts the changes required by the device from the previous validateDisplay
+ * call (which may be queried using getChangedCompositionTypes) and revalidates
+ * the display. This function is equivalent to requesting the changed types from
+ * getChangedCompositionTypes, setting those types on the corresponding layers,
+ * and then calling validateDisplay again.
+ *
+ * After this call it must be valid to present this display. Calling this after
+ * validateDisplay returns 0 changes must succeed with HWC2_ERROR_NONE, but
+ * should have no other effect.
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_NOT_VALIDATED - validateDisplay has not been called
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_ACCEPT_DISPLAY_CHANGES)(
+        hwc2_device_t* device, hwc2_display_t display);
+
+/* createLayer(..., outLayer)
+ * Descriptor: HWC2_FUNCTION_CREATE_LAYER
+ * Must be provided by all HWC2 devices
+ *
+ * Creates a new layer on the given display.
+ *
+ * Parameters:
+ *   outLayer - the handle of the new layer; pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_NO_RESOURCES - the device was unable to create this layer
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_CREATE_LAYER)(hwc2_device_t* device,
+        hwc2_display_t display, hwc2_layer_t* outLayer);
+
+/* destroyLayer(..., layer)
+ * Descriptor: HWC2_FUNCTION_DESTROY_LAYER
+ * Must be provided by all HWC2 devices
+ *
+ * Destroys the given layer.
+ *
+ * Parameters:
+ *   layer - the handle of the layer to destroy
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_DESTROY_LAYER)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer);
+
+/* getActiveConfig(..., outConfig)
+ * Descriptor: HWC2_FUNCTION_GET_ACTIVE_CONFIG
+ * Must be provided by all HWC2 devices
+ *
+ * Retrieves which display configuration is currently active.
+ *
+ * If no display configuration is currently active, this function must return
+ * HWC2_ERROR_BAD_CONFIG and place no configuration handle in outConfig. It is
+ * the responsibility of the client to call setActiveConfig with a valid
+ * configuration before attempting to present anything on the display.
+ *
+ * Parameters:
+ *   outConfig - the currently active display configuration; pointer will be
+ *       non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_CONFIG - no configuration is currently active
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_ACTIVE_CONFIG)(
+        hwc2_device_t* device, hwc2_display_t display,
+        hwc2_config_t* outConfig);
+
+/* getChangedCompositionTypes(..., outNumElements, outLayers, outTypes)
+ * Descriptor: HWC2_FUNCTION_GET_CHANGED_COMPOSITION_TYPES
+ * Must be provided by all HWC2 devices
+ *
+ * Retrieves the layers for which the device requires a different composition
+ * type than had been set prior to the last call to validateDisplay. The client
+ * will either update its state with these types and call acceptDisplayChanges,
+ * or will set new types and attempt to validate the display again.
+ *
+ * outLayers and outTypes may be NULL to retrieve the number of elements which
+ * will be returned. The number of elements returned must be the same as the
+ * value returned in outNumTypes from the last call to validateDisplay.
+ *
+ * Parameters:
+ *   outNumElements - if outLayers or outTypes were NULL, the number of layers
+ *       and types which would have been returned; if both were non-NULL, the
+ *       number of elements returned in outLayers and outTypes, which must not
+ *       exceed the value stored in outNumElements prior to the call; pointer
+ *       will be non-NULL
+ *   outLayers - an array of layer handles
+ *   outTypes - an array of composition types, each corresponding to an element
+ *       of outLayers
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_NOT_VALIDATED - validateDisplay has not been called for this
+ *       display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_CHANGED_COMPOSITION_TYPES)(
+        hwc2_device_t* device, hwc2_display_t display,
+        uint32_t* outNumElements, hwc2_layer_t* outLayers,
+        int32_t* /*hwc2_composition_t*/ outTypes);
+
+/* getClientTargetSupport(..., width, height, format, dataspace)
+ * Descriptor: HWC2_FUNCTION_GET_CLIENT_TARGET_SUPPORT
+ * Must be provided by all HWC2 devices
+ *
+ * Returns whether a client target with the given properties can be handled by
+ * the device.
+ *
+ * The valid formats can be found in android_pixel_format_t in
+ * <system/graphics.h>.
+ *
+ * For more about dataspaces, see setLayerDataspace.
+ *
+ * This function must return true for a client target with width and height
+ * equal to the active display configuration dimensions,
+ * HAL_PIXEL_FORMAT_RGBA_8888, and HAL_DATASPACE_UNKNOWN. It is not required to
+ * return true for any other configuration.
+ *
+ * Parameters:
+ *   width - client target width in pixels
+ *   height - client target height in pixels
+ *   format - client target format
+ *   dataspace - client target dataspace, as described in setLayerDataspace
+ *
+ * Returns HWC2_ERROR_NONE if the given configuration is supported or one of the
+ * following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_UNSUPPORTED - the given configuration is not supported
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_CLIENT_TARGET_SUPPORT)(
+        hwc2_device_t* device, hwc2_display_t display, uint32_t width,
+        uint32_t height, int32_t /*android_pixel_format_t*/ format,
+        int32_t /*android_dataspace_t*/ dataspace);
+
+/* getColorModes(..., outNumModes, outModes)
+ * Descriptor: HWC2_FUNCTION_GET_COLOR_MODES
+ * Must be provided by all HWC2 devices
+ *
+ * Returns the color modes supported on this display.
+ *
+ * The valid color modes can be found in android_color_mode_t in
+ * <system/graphics.h>. All HWC2 devices must support at least
+ * HAL_COLOR_MODE_NATIVE.
+ *
+ * outNumModes may be NULL to retrieve the number of modes which will be
+ * returned.
+ *
+ * Parameters:
+ *   outNumModes - if outModes was NULL, the number of modes which would have
+ *       been returned; if outModes was not NULL, the number of modes returned,
+ *       which must not exceed the value stored in outNumModes prior to the
+ *       call; pointer will be non-NULL
+ *   outModes - an array of color modes
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_COLOR_MODES)(
+        hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumModes,
+        int32_t* /*android_color_mode_t*/ outModes);
+
+/* getDisplayAttribute(..., config, attribute, outValue)
+ * Descriptor: HWC2_FUNCTION_GET_DISPLAY_ATTRIBUTE
+ * Must be provided by all HWC2 devices
+ *
+ * Returns a display attribute value for a particular display configuration.
+ *
+ * Any attribute which is not supported or for which the value is unknown by the
+ * device must return a value of -1.
+ *
+ * Parameters:
+ *   config - the display configuration for which to return attribute values
+ *   attribute - the attribute to query
+ *   outValue - the value of the attribute; the pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_CONFIG - config does not name a valid configuration for this
+ *       display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DISPLAY_ATTRIBUTE)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_config_t config,
+        int32_t /*hwc2_attribute_t*/ attribute, int32_t* outValue);
+
+/* getDisplayConfigs(..., outNumConfigs, outConfigs)
+ * Descriptor: HWC2_FUNCTION_GET_DISPLAY_CONFIGS
+ * Must be provided by all HWC2 devices
+ *
+ * Returns handles for all of the valid display configurations on this display.
+ *
+ * outConfigs may be NULL to retrieve the number of elements which will be
+ * returned.
+ *
+ * Parameters:
+ *   outNumConfigs - if outConfigs was NULL, the number of configurations which
+ *       would have been returned; if outConfigs was not NULL, the number of
+ *       configurations returned, which must not exceed the value stored in
+ *       outNumConfigs prior to the call; pointer will be non-NULL
+ *   outConfigs - an array of configuration handles
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DISPLAY_CONFIGS)(
+        hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumConfigs,
+        hwc2_config_t* outConfigs);
+
+/* getDisplayName(..., outSize, outName)
+ * Descriptor: HWC2_FUNCTION_GET_DISPLAY_NAME
+ * Must be provided by all HWC2 devices
+ *
+ * Returns a human-readable version of the display's name.
+ *
+ * outName may be NULL to retrieve the length of the name.
+ *
+ * Parameters:
+ *   outSize - if outName was NULL, the number of bytes needed to return the
+ *       name if outName was not NULL, the number of bytes written into it,
+ *       which must not exceed the value stored in outSize prior to the call;
+ *       pointer will be non-NULL
+ *   outName - the display's name
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DISPLAY_NAME)(
+        hwc2_device_t* device, hwc2_display_t display, uint32_t* outSize,
+        char* outName);
+
+/* getDisplayRequests(..., outDisplayRequests, outNumElements, outLayers,
+ *     outLayerRequests)
+ * Descriptor: HWC2_FUNCTION_GET_DISPLAY_REQUESTS
+ * Must be provided by all HWC2 devices
+ *
+ * Returns the display requests and the layer requests required for the last
+ * validated configuration.
+ *
+ * Display requests provide information about how the client should handle the
+ * client target. Layer requests provide information about how the client
+ * should handle an individual layer.
+ *
+ * If outLayers or outLayerRequests is NULL, the required number of layers and
+ * requests must be returned in outNumElements, but this number may also be
+ * obtained from validateDisplay as outNumRequests (outNumElements must be equal
+ * to the value returned in outNumRequests from the last call to
+ * validateDisplay).
+ *
+ * Parameters:
+ *   outDisplayRequests - the display requests for the current validated state
+ *   outNumElements - if outLayers or outLayerRequests were NULL, the number of
+ *       elements which would have been returned, which must be equal to the
+ *       value returned in outNumRequests from the last validateDisplay call on
+ *       this display; if both were not NULL, the number of elements in
+ *       outLayers and outLayerRequests, which must not exceed the value stored
+ *       in outNumElements prior to the call; pointer will be non-NULL
+ *   outLayers - an array of layers which all have at least one request
+ *   outLayerRequests - the requests corresponding to each element of outLayers
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_NOT_VALIDATED - validateDisplay has not been called for this
+ *       display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DISPLAY_REQUESTS)(
+        hwc2_device_t* device, hwc2_display_t display,
+        int32_t* /*hwc2_display_request_t*/ outDisplayRequests,
+        uint32_t* outNumElements, hwc2_layer_t* outLayers,
+        int32_t* /*hwc2_layer_request_t*/ outLayerRequests);
+
+/* getDisplayType(..., outType)
+ * Descriptor: HWC2_FUNCTION_GET_DISPLAY_TYPE
+ * Must be provided by all HWC2 devices
+ *
+ * Returns whether the given display is a physical or virtual display.
+ *
+ * Parameters:
+ *   outType - the type of the display; pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DISPLAY_TYPE)(
+        hwc2_device_t* device, hwc2_display_t display,
+        int32_t* /*hwc2_display_type_t*/ outType);
+
+/* getDozeSupport(..., outSupport)
+ * Descriptor: HWC2_FUNCTION_GET_DOZE_SUPPORT
+ * Must be provided by all HWC2 devices
+ *
+ * Returns whether the given display supports HWC2_POWER_MODE_DOZE and
+ * HWC2_POWER_MODE_DOZE_SUSPEND. DOZE_SUSPEND may not provide any benefit over
+ * DOZE (see the definition of hwc2_power_mode_t for more information), but if
+ * both DOZE and DOZE_SUSPEND are no different from HWC2_POWER_MODE_ON, the
+ * device should not claim support.
+ *
+ * Parameters:
+ *   outSupport - whether the display supports doze modes (1 for yes, 0 for no);
+ *       pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_DOZE_SUPPORT)(
+        hwc2_device_t* device, hwc2_display_t display, int32_t* outSupport);
+
+/* getReleaseFences(..., outNumElements, outLayers, outFences)
+ * Descriptor: HWC2_FUNCTION_GET_RELEASE_FENCES
+ * Must be provided by all HWC2 devices
+ *
+ * Retrieves the release fences for device layers on this display which will
+ * receive new buffer contents this frame.
+ *
+ * A release fence is a file descriptor referring to a sync fence object which
+ * will be signaled after the device has finished reading from the buffer
+ * presented in the prior frame. This indicates that it is safe to start writing
+ * to the buffer again. If a given layer's fence is not returned from this
+ * function, it will be assumed that the buffer presented on the previous frame
+ * is ready to be written.
+ *
+ * The fences returned by this function should be unique for each layer (even if
+ * they point to the same underlying sync object), and ownership of the fences
+ * is transferred to the client, which is responsible for closing them.
+ *
+ * If outLayers or outFences is NULL, the required number of layers and fences
+ * must be returned in outNumElements.
+ *
+ * Parameters:
+ *   outNumElements - if outLayers or outFences were NULL, the number of
+ *       elements which would have been returned; if both were not NULL, the
+ *       number of elements in outLayers and outFences, which must not exceed
+ *       the value stored in outNumElements prior to the call; pointer will be
+ *       non-NULL
+ *   outLayers - an array of layer handles
+ *   outFences - an array of sync fence file descriptors as described above,
+ *       each corresponding to an element of outLayers
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_GET_RELEASE_FENCES)(
+        hwc2_device_t* device, hwc2_display_t display, uint32_t* outNumElements,
+        hwc2_layer_t* outLayers, int32_t* outFences);
+
+/* presentDisplay(..., outRetireFence)
+ * Descriptor: HWC2_FUNCTION_PRESENT_DISPLAY
+ * Must be provided by all HWC2 devices
+ *
+ * Presents the current display contents on the screen (or in the case of
+ * virtual displays, into the output buffer).
+ *
+ * Prior to calling this function, the display must be successfully validated
+ * with validateDisplay. Note that setLayerBuffer and setLayerSurfaceDamage
+ * specifically do not count as layer state, so if there are no other changes
+ * to the layer state (or to the buffer's properties as described in
+ * setLayerBuffer), then it is safe to call this function without first
+ * validating the display.
+ *
+ * If this call succeeds, outRetireFence will be populated with a file
+ * descriptor referring to a retire sync fence object. For physical displays,
+ * this fence will be signaled when the result of composition of the prior frame
+ * is no longer necessary (because it has been copied or replaced by this
+ * frame). For virtual displays, this fence will be signaled when writes to the
+ * output buffer have completed and it is safe to read from it.
+ *
+ * Parameters:
+ *   outRetireFence - a sync fence file descriptor as described above; pointer
+ *       will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_NO_RESOURCES - no valid output buffer has been set for a virtual
+ *       display
+ *   HWC2_ERROR_NOT_VALIDATED - validateDisplay has not successfully been called
+ *       for this display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_PRESENT_DISPLAY)(
+        hwc2_device_t* device, hwc2_display_t display, int32_t* outRetireFence);
+
+/* setActiveConfig(..., config)
+ * Descriptor: HWC2_FUNCTION_SET_ACTIVE_CONFIG
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the active configuration for this display. Upon returning, the given
+ * display configuration should be active and remain so until either this
+ * function is called again or the display is disconnected.
+ *
+ * Parameters:
+ *   config - the new display configuration
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_CONFIG - the configuration handle passed in is not valid for
+ *       this display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_ACTIVE_CONFIG)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_config_t config);
+
+/* setClientTarget(..., target, acquireFence, dataspace)
+ * Descriptor: HWC2_FUNCTION_SET_CLIENT_TARGET
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the buffer handle which will receive the output of client composition.
+ * Layers marked as HWC2_COMPOSITION_CLIENT will be composited into this buffer
+ * prior to the call to presentDisplay, and layers not marked as
+ * HWC2_COMPOSITION_CLIENT should be composited with this buffer by the device.
+ *
+ * Also provides a file descriptor referring to an acquire sync fence object,
+ * which will be signaled when it is safe to read from the client target buffer.
+ * If it is already safe to read from this buffer, -1 may be passed instead.
+ * The device must ensure that it is safe for the client to close this file
+ * descriptor at any point after this function is called.
+ *
+ * For more about dataspaces, see setLayerDataspace.
+ *
+ * Will be called before presentDisplay if any of the layers are marked as
+ * HWC2_COMPOSITION_CLIENT. If no layers are so marked, then it is not
+ * necessary to call this function. It is not necessary to call validateDisplay
+ * after changing the target through this function.
+ *
+ * Parameters:
+ *   target - the new target buffer
+ *   acquireFence - a sync fence file descriptor as described above
+ *   dataspace - the dataspace of the buffer, as described in setLayerDataspace
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - the new target handle was invalid
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_CLIENT_TARGET)(
+        hwc2_device_t* device, hwc2_display_t display, buffer_handle_t target,
+        int32_t acquireFence, int32_t /*android_dataspace_t*/ dataspace);
+
+/* setColorTransform(..., matrix, hint)
+ * Descriptor: HWC2_FUNCTION_SET_COLOR_TRANSFORM
+ * Must be provided by all HWC2 devices
+ *
+ * Sets a color transform which will be applied after composition.
+ *
+ * If hint is not HAL_COLOR_TRANSFORM_ARBITRARY, then the device may use the
+ * hint to apply the desired color transform instead of using the color matrix
+ * directly.
+ *
+ * If the device is not capable of either using the hint or the matrix to apply
+ * the desired color transform, it should force all layers to client composition
+ * during validateDisplay.
+ *
+ * The matrix provided is an affine color transformation of the following form:
+ *
+ * |r.r r.g r.b 0|
+ * |g.r g.g g.b 0|
+ * |b.r b.g b.b 0|
+ * |Tr  Tg  Tb  1|
+ *
+ * This matrix will be provided in row-major form: {r.r, r.g, r.b, 0, g.r, ...}.
+ *
+ * Given a matrix of this form and an input color [R_in, G_in, B_in], the output
+ * color [R_out, G_out, B_out] will be:
+ *
+ * R_out = R_in * r.r + G_in * g.r + B_in * b.r + Tr
+ * G_out = G_in * r.g + G_in * g.g + B_in * b.g + Tg
+ * B_out = B_in * r.b + G_in * g.b + B_in * b.b + Tb
+ *
+ * Parameters:
+ *   matrix - a 4x4 transform matrix (16 floats) as described above
+ *   hint - a hint value which may be used instead of the given matrix unless it
+ *       is HAL_COLOR_TRANSFORM_ARBITRARY
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - hint is not a valid color transform hint
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_COLOR_TRANSFORM)(
+        hwc2_device_t* device, hwc2_display_t display, float* matrix,
+        int32_t /*android_color_transform_t*/ hint);
+
+/* setColorMode(..., mode)
+ * Descriptor: HWC2_FUNCTION_SET_COLOR_MODE
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the color mode of the given display.
+ *
+ * Upon returning from this function, the color mode change must have fully
+ * taken effect.
+ *
+ * The valid color modes can be found in android_color_mode_t in
+ * <system/graphics.h>. All HWC2 devices must support at least
+ * HAL_COLOR_MODE_NATIVE, and displays are assumed to be in this mode upon
+ * hotplug.
+ *
+ * Parameters:
+ *   mode - the mode to set
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - mode is not a valid color mode
+ *   HWC2_ERROR_UNSUPPORTED - mode is not supported on this display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_COLOR_MODE)(
+        hwc2_device_t* device, hwc2_display_t display,
+        int32_t /*android_color_mode_t*/ mode);
+
+/* setOutputBuffer(..., buffer, releaseFence)
+ * Descriptor: HWC2_FUNCTION_SET_OUTPUT_BUFFER
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the output buffer for a virtual display. That is, the buffer to which
+ * the composition result will be written.
+ *
+ * Also provides a file descriptor referring to a release sync fence object,
+ * which will be signaled when it is safe to write to the output buffer. If it
+ * is already safe to write to the output buffer, -1 may be passed instead. The
+ * device must ensure that it is safe for the client to close this file
+ * descriptor at any point after this function is called.
+ *
+ * Must be called at least once before presentDisplay, but does not have any
+ * interaction with layer state or display validation.
+ *
+ * Parameters:
+ *   buffer - the new output buffer
+ *   releaseFence - a sync fence file descriptor as described above
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - the new output buffer handle was invalid
+ *   HWC2_ERROR_UNSUPPORTED - display does not refer to a virtual display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_OUTPUT_BUFFER)(
+        hwc2_device_t* device, hwc2_display_t display, buffer_handle_t buffer,
+        int32_t releaseFence);
+
+/* setPowerMode(..., mode)
+ * Descriptor: HWC2_FUNCTION_SET_POWER_MODE
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the power mode of the given display. The transition must be complete
+ * when this function returns. It is valid to call this function multiple times
+ * with the same power mode.
+ *
+ * All displays must support HWC2_POWER_MODE_ON and HWC2_POWER_MODE_OFF. Whether
+ * a display supports HWC2_POWER_MODE_DOZE or HWC2_POWER_MODE_DOZE_SUSPEND may
+ * be queried using getDozeSupport.
+ *
+ * Parameters:
+ *   mode - the new power mode
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - mode was not a valid power mode
+ *   HWC2_ERROR_UNSUPPORTED - mode was a valid power mode, but is not supported
+ *       on this display
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_POWER_MODE)(
+        hwc2_device_t* device, hwc2_display_t display,
+        int32_t /*hwc2_power_mode_t*/ mode);
+
+/* setVsyncEnabled(..., enabled)
+ * Descriptor: HWC2_FUNCTION_SET_VSYNC_ENABLED
+ * Must be provided by all HWC2 devices
+ *
+ * Enables or disables the vsync signal for the given display. Virtual displays
+ * never generate vsync callbacks, and any attempt to enable vsync for a virtual
+ * display though this function must return HWC2_ERROR_NONE and have no other
+ * effect.
+ *
+ * Parameters:
+ *   enabled - whether to enable or disable vsync
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - enabled was an invalid value
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_VSYNC_ENABLED)(
+        hwc2_device_t* device, hwc2_display_t display,
+        int32_t /*hwc2_vsync_t*/ enabled);
+
+/* validateDisplay(..., outNumTypes, outNumRequests)
+ * Descriptor: HWC2_FUNCTION_VALIDATE_DISPLAY
+ * Must be provided by all HWC2 devices
+ *
+ * Instructs the device to inspect all of the layer state and determine if
+ * there are any composition type changes necessary before presenting the
+ * display. Permitted changes are described in the definition of
+ * hwc2_composition_t above.
+ *
+ * Also returns the number of layer requests required
+ * by the given layer configuration.
+ *
+ * Parameters:
+ *   outNumTypes - the number of composition type changes required by the
+ *       device; if greater than 0, the client must either set and validate new
+ *       types, or call acceptDisplayChanges to accept the changes returned by
+ *       getChangedCompositionTypes; must be the same as the number of changes
+ *       returned by getChangedCompositionTypes (see the declaration of that
+ *       function for more information); pointer will be non-NULL
+ *   outNumRequests - the number of layer requests required by this layer
+ *       configuration; must be equal to the number of layer requests returned
+ *       by getDisplayRequests (see the declaration of that function for
+ *       more information); pointer will be non-NULL
+ *
+ * Returns HWC2_ERROR_NONE if no changes are necessary and it is safe to present
+ * the display using the current layer state. Otherwise returns one of the
+ * following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_HAS_CHANGES - outNumTypes was greater than 0 (see parameter list
+ *       for more information)
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_VALIDATE_DISPLAY)(
+        hwc2_device_t* device, hwc2_display_t display,
+        uint32_t* outNumTypes, uint32_t* outNumRequests);
+
+/*
+ * Layer Functions
+ *
+ * These are functions which operate on layers, but which do not modify state
+ * that must be validated before use. See also 'Layer State Functions' below.
+ *
+ * All of these functions take as their first three parameters a device pointer,
+ * a display handle for the display which contains the layer, and a layer
+ * handle, so these parameters are omitted from the described parameter lists.
+ */
+
+/* setCursorPosition(..., x, y)
+ * Descriptor: HWC2_FUNCTION_SET_CURSOR_POSITION
+ * Must be provided by all HWC2 devices
+ *
+ * Asynchonously sets the position of a cursor layer.
+ *
+ * Prior to validateDisplay, a layer may be marked as HWC2_COMPOSITION_CURSOR.
+ * If validation succeeds (i.e., the device does not request a composition
+ * change for that layer), then once a buffer has been set for the layer and it
+ * has been presented, its position may be set by this function at any time
+ * between presentDisplay and any subsequent validateDisplay calls for this
+ * display.
+ *
+ * Once validateDisplay is called, this function will not be called again until
+ * the validate/present sequence is completed.
+ *
+ * May be called from any thread so long as it is not interleaved with the
+ * validate/present sequence as described above.
+ *
+ * Parameters:
+ *   x - the new x coordinate (in pixels from the left of the screen)
+ *   y - the new y coordinate (in pixels from the top of the screen)
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_DISPLAY - an invalid display handle was passed in
+ *   HWC2_ERROR_BAD_LAYER - the layer is invalid or is not currently marked as
+ *       HWC2_COMPOSITION_CURSOR
+ *   HWC2_ERROR_NOT_VALIDATED - the device is currently in the middle of the
+ *       validate/present sequence
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_CURSOR_POSITION)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        int32_t x, int32_t y);
+
+/* setLayerBuffer(..., buffer, acquireFence)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_BUFFER
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the buffer handle to be displayed for this layer. If the buffer
+ * properties set at allocation time (width, height, format, and usage) have not
+ * changed since the previous frame, it is not necessary to call validateDisplay
+ * before calling presentDisplay unless new state needs to be validated in the
+ * interim.
+ *
+ * Also provides a file descriptor referring to an acquire sync fence object,
+ * which will be signaled when it is safe to read from the given buffer. If it
+ * is already safe to read from the buffer, -1 may be passed instead. The
+ * device must ensure that it is safe for the client to close this file
+ * descriptor at any point after this function is called.
+ *
+ * This function must return HWC2_ERROR_NONE and have no other effect if called
+ * for a layer with a composition type of HWC2_COMPOSITION_SOLID_COLOR (because
+ * it has no buffer) or HWC2_COMPOSITION_SIDEBAND or HWC2_COMPOSITION_CLIENT
+ * (because synchronization and buffer updates for these layers are handled
+ * elsewhere).
+ *
+ * Parameters:
+ *   buffer - the buffer handle to set
+ *   acquireFence - a sync fence file descriptor as described above
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - the buffer handle passed in was invalid
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_BUFFER)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        buffer_handle_t buffer, int32_t acquireFence);
+
+/* setLayerSurfaceDamage(..., damage)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_SURFACE_DAMAGE
+ * Must be provided by all HWC2 devices
+ *
+ * Provides the region of the source buffer which has been modified since the
+ * last frame. This region does not need to be validated before calling
+ * presentDisplay.
+ *
+ * Once set through this function, the damage region remains the same until a
+ * subsequent call to this function.
+ *
+ * If damage.numRects > 0, then it may be assumed that any portion of the source
+ * buffer not covered by one of the rects has not been modified this frame. If
+ * damage.numRects == 0, then the whole source buffer must be treated as if it
+ * has been modified.
+ *
+ * If the layer's contents are not modified relative to the prior frame, damage
+ * will contain exactly one empty rect([0, 0, 0, 0]).
+ *
+ * The damage rects are relative to the pre-transformed buffer, and their origin
+ * is the top-left corner. They will not exceed the dimensions of the latched
+ * buffer.
+ *
+ * Parameters:
+ *   damage - the new surface damage region
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_SURFACE_DAMAGE)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        hwc_region_t damage);
+
+/*
+ * Layer State Functions
+ *
+ * These functions modify the state of a given layer. They do not take effect
+ * until the display configuration is successfully validated with
+ * validateDisplay and the display contents are presented with presentDisplay.
+ *
+ * All of these functions take as their first three parameters a device pointer,
+ * a display handle for the display which contains the layer, and a layer
+ * handle, so these parameters are omitted from the described parameter lists.
+ */
+
+/* setLayerBlendMode(..., mode)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_BLEND_MODE
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the blend mode of the given layer.
+ *
+ * Parameters:
+ *   mode - the new blend mode
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - an invalid blend mode was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_BLEND_MODE)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        int32_t /*hwc2_blend_mode_t*/ mode);
+
+/* setLayerColor(..., color)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_COLOR
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the color of the given layer. If the composition type of the layer is
+ * not HWC2_COMPOSITION_SOLID_COLOR, this call must return HWC2_ERROR_NONE and
+ * have no other effect.
+ *
+ * Parameters:
+ *   color - the new color
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_COLOR)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        hwc_color_t color);
+
+/* setLayerCompositionType(..., type)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_COMPOSITION_TYPE
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the desired composition type of the given layer. During validateDisplay,
+ * the device may request changes to the composition types of any of the layers
+ * as described in the definition of hwc2_composition_t above.
+ *
+ * Parameters:
+ *   type - the new composition type
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - an invalid composition type was passed in
+ *   HWC2_ERROR_UNSUPPORTED - a valid composition type was passed in, but it is
+ *       not supported by this device
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_COMPOSITION_TYPE)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        int32_t /*hwc2_composition_t*/ type);
+
+/* setLayerDataspace(..., dataspace)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_DATASPACE
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the dataspace that the current buffer on this layer is in.
+ *
+ * The dataspace provides more information about how to interpret the buffer
+ * contents, such as the encoding standard and color transform.
+ *
+ * See the values of android_dataspace_t in <system/graphics.h> for more
+ * information.
+ *
+ * Parameters:
+ *   dataspace - the new dataspace
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_DATASPACE)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        int32_t /*android_dataspace_t*/ dataspace);
+
+/* setLayerDisplayFrame(..., frame)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_DISPLAY_FRAME
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the display frame (the portion of the display covered by a layer) of the
+ * given layer. This frame will not exceed the display dimensions.
+ *
+ * Parameters:
+ *   frame - the new display frame
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_DISPLAY_FRAME)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        hwc_rect_t frame);
+
+/* setLayerPlaneAlpha(..., alpha)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_PLANE_ALPHA
+ * Must be provided by all HWC2 devices
+ *
+ * Sets an alpha value (a floating point value in the range [0.0, 1.0]) which
+ * will be applied to the whole layer. It can be conceptualized as a
+ * preprocessing step which applies the following function:
+ *   if (blendMode == HWC2_BLEND_MODE_PREMULTIPLIED)
+ *       out.rgb = in.rgb * planeAlpha
+ *   out.a = in.a * planeAlpha
+ *
+ * If the device does not support this operation on a layer which is marked
+ * HWC2_COMPOSITION_DEVICE, it must request a composition type change to
+ * HWC2_COMPOSITION_CLIENT upon the next validateDisplay call.
+ *
+ * Parameters:
+ *   alpha - the plane alpha value to apply
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_PLANE_ALPHA)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        float alpha);
+
+/* setLayerSidebandStream(..., stream)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_SIDEBAND_STREAM
+ * Provided by HWC2 devices which support HWC2_CAPABILITY_SIDEBAND_STREAM
+ *
+ * Sets the sideband stream for this layer. If the composition type of the given
+ * layer is not HWC2_COMPOSITION_SIDEBAND, this call must return HWC2_ERROR_NONE
+ * and have no other effect.
+ *
+ * Parameters:
+ *   stream - the new sideband stream
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - an invalid sideband stream was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_SIDEBAND_STREAM)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        const native_handle_t* stream);
+
+/* setLayerSourceCrop(..., crop)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_SOURCE_CROP
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the source crop (the portion of the source buffer which will fill the
+ * display frame) of the given layer. This crop rectangle will not exceed the
+ * dimensions of the latched buffer.
+ *
+ * If the device is not capable of supporting a true float source crop (i.e., it
+ * will truncate or round the floats to integers), it should set this layer to
+ * HWC2_COMPOSITION_CLIENT when crop is non-integral for the most accurate
+ * rendering.
+ *
+ * If the device cannot support float source crops, but still wants to handle
+ * the layer, it should use the following code (or similar) to convert to
+ * an integer crop:
+ *   intCrop.left = (int) ceilf(crop.left);
+ *   intCrop.top = (int) ceilf(crop.top);
+ *   intCrop.right = (int) floorf(crop.right);
+ *   intCrop.bottom = (int) floorf(crop.bottom);
+ *
+ * Parameters:
+ *   crop - the new source crop
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_SOURCE_CROP)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        hwc_frect_t crop);
+
+/* setLayerTransform(..., transform)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_TRANSFORM
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the transform (rotation/flip) of the given layer.
+ *
+ * Parameters:
+ *   transform - the new transform
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ *   HWC2_ERROR_BAD_PARAMETER - an invalid transform was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_TRANSFORM)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        int32_t /*hwc_transform_t*/ transform);
+
+/* setLayerVisibleRegion(..., visible)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_VISIBLE_REGION
+ * Must be provided by all HWC2 devices
+ *
+ * Specifies the portion of the layer that is visible, including portions under
+ * translucent areas of other layers. The region is in screen space, and will
+ * not exceed the dimensions of the screen.
+ *
+ * Parameters:
+ *   visible - the new visible region, in screen space
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_VISIBLE_REGION)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        hwc_region_t visible);
+
+/* setLayerZOrder(..., z)
+ * Descriptor: HWC2_FUNCTION_SET_LAYER_Z_ORDER
+ * Must be provided by all HWC2 devices
+ *
+ * Sets the desired Z order (height) of the given layer. A layer with a greater
+ * Z value occludes a layer with a lesser Z value.
+ *
+ * Parameters:
+ *   z - the new Z order
+ *
+ * Returns HWC2_ERROR_NONE or one of the following errors:
+ *   HWC2_ERROR_BAD_LAYER - an invalid layer handle was passed in
+ */
+typedef int32_t /*hwc2_error_t*/ (*HWC2_PFN_SET_LAYER_Z_ORDER)(
+        hwc2_device_t* device, hwc2_display_t display, hwc2_layer_t layer,
+        uint32_t z);
+
+__END_DECLS
+
+#endif