diff --git a/include/hardware/hwcomposer.h b/include/hardware/hwcomposer.h
index 895c695..29ea54c 100644
--- a/include/hardware/hwcomposer.h
+++ b/include/hardware/hwcomposer.h
@@ -59,39 +59,6 @@
  */
 #define HWC_HARDWARE_COMPOSER   "composer"
 
-struct hwc_composer_device_1;
-typedef struct hwc_methods_1 {
-
-    /*
-     * eventControl(..., event, enabled)
-     * Enables or disables h/w composer events for a display.
-     *
-     * eventControl can be called from any thread and takes effect
-     * immediately.
-     *
-     *  Supported events are:
-     *      HWC_EVENT_VSYNC
-     *
-     * returns -EINVAL if the "event" parameter is not one of the value above
-     * or if the "enabled" parameter is not 0 or 1.
-     */
-    int (*eventControl)(
-            struct hwc_composer_device_1* dev, int dpy,
-            int event, int enabled);
-
-    /*
-     * blank(..., blank)
-     * Blanks or unblanks a display's screen.
-     *
-     * Turns the screen off when blank is nonzero, on when blank is zero.
-     * Multiple sequential calls with the same blank value must be supported.
-     *
-     * returns 0 on success, negative on error.
-     */
-    int (*blank)(struct hwc_composer_device_1* dev, int dpy, int blank);
-
-} hwc_methods_1_t;
-
 typedef struct hwc_rect {
     int left;
     int top;
@@ -113,20 +80,30 @@
 
 typedef struct hwc_layer_1 {
     /*
-     * initially set to HWC_FRAMEBUFFER or HWC_BACKGROUND.
+     * Initially set to HWC_FRAMEBUFFER, HWC_BACKGROUND, or
+     * HWC_FRAMEBUFFER_TARGET.
+     *
      * HWC_FRAMEBUFFER
-     *   indicates the layer will be drawn into the framebuffer
-     *   using OpenGL ES.
-     *   The HWC can toggle this value to HWC_OVERLAY, to indicate
-     *   it will handle the layer.
+     *   Indicates the layer will be drawn into the framebuffer
+     *   using OpenGL ES. The HWC can toggle this value to HWC_OVERLAY to
+     *   indicate it will handle the layer.
      *
      * HWC_BACKGROUND
-     *   indicates this is a special "background"  layer. The only valid
-     *   field is backgroundColor. HWC_BACKGROUND can only be used with
-     *   HWC_API_VERSION >= 0.2
-     *   The HWC can toggle this value to HWC_FRAMEBUFFER, to indicate
-     *   it CANNOT handle the background color
+     *   Indicates this is a special "background" layer. The only valid field
+     *   is backgroundColor. The HWC can toggle this value to HWC_FRAMEBUFFER
+     *   to indicate it CANNOT handle the background color.
      *
+     * HWC_FRAMEBUFFER_TARGET
+     *   Indicates this layer is the framebuffer surface used as the target of
+     *   OpenGL ES composition. If the HWC sets all other layers to HWC_OVERLAY
+     *   or HWC_BACKGROUND, then no OpenGL ES composition will be done, and
+     *   this layer should be ignored during set(); the HWC_SKIP_LAYER flag
+     *   will indicate this case.
+     *
+     *   This flag (and the framebuffer surface layer) will only be used if the
+     *   HWC version is HWC_DEVICE_API_VERSION_1_1 or higher. In older versions,
+     *   the OpenGL ES target surface is communicated by the (dpy, sur) fields
+     *   in hwc_compositor_device_1_t.
      */
     int32_t compositionType;
 
@@ -178,6 +155,10 @@
              * fence to be signaled before returning, but the HWC must wait for
              * all buffers to be signaled before reading from them.
              *
+             * HWC_FRAMEBUFFER layers will never have an acquire fence, since
+             * reads from them are complete before the framebuffer is ready for
+             * display.
+             *
              * The HWC takes ownership of the acquireFenceFd and is responsible
              * for closing it when no longer needed.
              */
@@ -197,6 +178,10 @@
              * the blit completes, but the overlay layers can't be reused until
              * a subsequent frame has been displayed.
              *
+             * Since HWC doesn't read from HWC_FRAMEBUFFER layers, it shouldn't
+             * produce a release fence for them. The releaseFenceFd will be -1
+             * for these layers when set() is called.
+             *
              * The HWC client taks ownership of the releaseFenceFd and is
              * responsible for closing it when no longer needed.
              */
@@ -244,9 +229,13 @@
      */
     int flipFenceFd;
 
-    /* (dpy, sur) is the target of SurfaceFlinger's OpenGL ES composition.
-     * They aren't relevant to prepare. The set call should commit this surface
-     * atomically to the display along with any overlay layers.
+    /* (dpy, sur) is the target of SurfaceFlinger's OpenGL ES composition for
+     * HWC versions before HWC_DEVICE_VERSION_1_1. They aren't relevant to
+     * prepare. The set call should commit this surface atomically to the
+     * display along with any overlay layers.
+     *
+     * For HWC_DEVICE_VERSION_1_1 and later, these will always be set to
+     * EGL_NO_DISPLAY and EGL_NO_SURFACE.
      */
     hwc_display_t dpy;
     hwc_surface_t sur;
@@ -262,8 +251,7 @@
 } hwc_display_contents_1_t;
 
 /* see hwc_composer_device::registerProcs()
- * Any of the callbacks can be NULL, in which case the corresponding
- * functionality is not supported.
+ * All of the callbacks are required and non-NULL unless otherwise noted.
  */
 typedef struct hwc_procs {
     /*
@@ -275,7 +263,7 @@
      * it is safe to call invalidate() from any of hwc_composer_device
      * hooks, unless noted otherwise.
      */
-    void (*invalidate)(struct hwc_procs* procs);
+    void (*invalidate)(const struct hwc_procs* procs);
 
     /*
      * (*vsync)() is called by the h/w composer HAL when a vsync event is
@@ -297,7 +285,7 @@
      * can either stop or continue to process VSYNC events, but must not
      * crash or cause other problems.
      */
-    void (*vsync)(struct hwc_procs* procs, int dpy, int64_t timestamp);
+    void (*vsync)(const struct hwc_procs* procs, int dpy, int64_t timestamp);
 } hwc_procs_t;
 
 
@@ -326,8 +314,16 @@
      * handles have been updated. Typically this happens (but is not limited to)
      * when a window is added, removed, resized or moved.
      *
-     * The numDisplays parameter will always be greater than zero, displays
-     * will be non-NULL, and the array entries will be non-NULL.
+     * For HWC 1.0, numDisplays will always be one, and displays[0] will be
+     * non-NULL.
+     *
+     * For HWC 1.1, numDisplays will always be HWC_NUM_DISPLAY_TYPES. Entries
+     * for unsupported or disabled/disconnected display types will be NULL.
+     *
+     * For HWC 1.2 and later, numDisplays will be HWC_NUM_DISPLAY_TYPES or more.
+     * The extra entries correspond to enabled virtual displays, and will be
+     * non-NULL. In HWC 1.2, support for one virtual display is required, and
+     * no more than one will be used. Future HWC versions might require more.
      *
      * returns: 0 on success. An negative error code on error. If an error is
      * returned, SurfaceFlinger will assume that none of the layer will be
@@ -352,8 +348,16 @@
      * been handled by SurfaceFlinger with OpenGL ES. In this case, (*set)()
      * behaves just like eglSwapBuffers().
      *
-     * The numDisplays parameter will always be greater than zero, displays
-     * will be non-NULL, and the array entries will be non-NULL.
+     * For HWC 1.0, numDisplays will always be one, and displays[0] will be
+     * non-NULL.
+     *
+     * For HWC 1.1, numDisplays will always be HWC_NUM_DISPLAY_TYPES. Entries
+     * for unsupported or disabled/disconnected display types will be NULL.
+     *
+     * For HWC 1.2 and later, numDisplays will be HWC_NUM_DISPLAY_TYPES or more.
+     * The extra entries correspond to enabled virtual displays, and will be
+     * non-NULL. In HWC 1.2, support for one virtual display is required, and
+     * no more than one will be used. Future HWC versions might require more.
      *
      * IMPORTANT NOTE: there is an implicit layer containing opaque black
      * pixels behind all the layers in the list. It is the responsibility of
@@ -368,31 +372,35 @@
                 size_t numDisplays, hwc_display_contents_1_t** displays);
 
     /*
-     * This field is OPTIONAL and can be NULL.
+     * eventControl(..., event, enabled)
+     * Enables or disables h/w composer events for a display.
      *
-     * If non NULL it will be called by SurfaceFlinger on dumpsys
+     * eventControl can be called from any thread and takes effect
+     * immediately.
+     *
+     *  Supported events are:
+     *      HWC_EVENT_VSYNC
+     *
+     * returns -EINVAL if the "event" parameter is not one of the value above
+     * or if the "enabled" parameter is not 0 or 1.
      */
-    void (*dump)(struct hwc_composer_device_1* dev, char *buff, int buff_len);
+    int (*eventControl)(struct hwc_composer_device_1* dev, int dpy,
+            int event, int enabled);
 
     /*
-     * This field is OPTIONAL and can be NULL.
+     * blank(..., blank)
+     * Blanks or unblanks a display's screen.
      *
-     * (*registerProcs)() registers a set of callbacks the h/w composer HAL
-     * can later use. It is FORBIDDEN to call any of the callbacks from
-     * within registerProcs(). registerProcs() must save the hwc_procs_t pointer
-     * which is needed when calling a registered callback.
-     * Each call to registerProcs replaces the previous set of callbacks.
-     * registerProcs is called with NULL to unregister all callbacks.
+     * Turns the screen off when blank is nonzero, on when blank is zero.
+     * Multiple sequential calls with the same blank value must be supported.
+     * The screen state transition must be be complete when the function
+     * returns.
      *
-     * Any of the callbacks can be NULL, in which case the corresponding
-     * functionality is not supported.
+     * returns 0 on success, negative on error.
      */
-    void (*registerProcs)(struct hwc_composer_device_1* dev,
-            hwc_procs_t const* procs);
+    int (*blank)(struct hwc_composer_device_1* dev, int dpy, int blank);
 
     /*
-     * This field is OPTIONAL and can be NULL.
-     *
      * Used to retrieve information about the h/w composer
      *
      * Returns 0 on success or -errno on error.
@@ -400,15 +408,27 @@
     int (*query)(struct hwc_composer_device_1* dev, int what, int* value);
 
     /*
+     * (*registerProcs)() registers callbacks that the h/w composer HAL can
+     * later use. It will be called immediately after the composer device is
+     * opened with non-NULL procs. It is FORBIDDEN to call any of the callbacks
+     * from within registerProcs(). registerProcs() must save the hwc_procs_t
+     * pointer which is needed when calling a registered callback.
+     */
+    void (*registerProcs)(struct hwc_composer_device_1* dev,
+            hwc_procs_t const* procs);
+
+    /*
+     * This field is OPTIONAL and can be NULL.
+     *
+     * If non NULL it will be called by SurfaceFlinger on dumpsys
+     */
+    void (*dump)(struct hwc_composer_device_1* dev, char *buff, int buff_len);
+
+    /*
      * Reserved for future use. Must be NULL.
      */
     void* reserved_proc[4];
 
-    /*
-     * This field is REQUIRED and must not be NULL.
-     */
-    hwc_methods_1_t const *methods;
-
 } hwc_composer_device_1_t;
 
 /** convenience API for opening and closing a device */
diff --git a/include/hardware/hwcomposer_defs.h b/include/hardware/hwcomposer_defs.h
index 02b8e50..f0f97fc 100644
--- a/include/hardware/hwcomposer_defs.h
+++ b/include/hardware/hwcomposer_defs.h
@@ -34,6 +34,7 @@
 #define HWC_DEVICE_API_VERSION_0_2  HARDWARE_DEVICE_API_VERSION(0, 2)
 #define HWC_DEVICE_API_VERSION_0_3  HARDWARE_DEVICE_API_VERSION(0, 3)
 #define HWC_DEVICE_API_VERSION_1_0  HARDWARE_DEVICE_API_VERSION(1, 0)
+#define HWC_DEVICE_API_VERSION_1_1  HARDWARE_DEVICE_API_VERSION(1, 1)
 
 enum {
     /* hwc_composer_device_t::set failed in EGL */
@@ -89,6 +90,10 @@
     /* this is the background layer. it's used to set the background color.
      * there is only a single background layer */
     HWC_BACKGROUND = 2,
+
+    /* this layer holds the result of compositing the HWC_FRAMEBUFFER layers.
+     * Added in HWC_DEVICE_API_VERSION_1_1. */
+    HWC_FRAMEBUFFER_TARGET = 3,
 };
 
 /*
@@ -134,6 +139,12 @@
      * returns the vsync period in nanosecond
      */
     HWC_VSYNC_PERIOD                    = 1,
+
+    /*
+     * availability: HWC_DEVICE_API_VERSION_1_1
+     * returns a mask of supported display types
+     */
+    HWC_DISPLAY_TYPES_SUPPORTED         = 2,
 };
 
 /* Allowed events for hwc_methods::eventControl() */
@@ -141,6 +152,18 @@
     HWC_EVENT_VSYNC     = 0
 };
 
+/* Display types and associated mask bits. */
+enum {
+    HWC_DISPLAY_PRIMARY     = 0,
+    HWC_DISPLAY_EXTERNAL    = 1,    // HDMI, DP, etc.
+    HWC_NUM_DISPLAY_TYPES
+};
+
+enum {
+    HWC_DISPLAY_PRIMARY_BIT     = 1 << HWC_DISPLAY_PRIMARY,
+    HWC_DISPLAY_EXTERNAL_BIT    = 1 << HWC_DISPLAY_EXTERNAL,
+};
+
 /*****************************************************************************/
 
 __END_DECLS