SurfaceFlinger: Add dim layer information into HWC layer.

- Set dim layer flag = 0x80000000 to send dim layer hint to HWC.
- Clear HWC_SKIP_LAYER flag when dim layer flag is set.

Change-Id: I56904c65fb487e6e89d4c057015443730d727299

services/surfaceflinger/DisplayHardware/HWComposer.cpp

@@ -190,6 +190,11 @@ HWComposer::HWComposer(
         // we don't have VSYNC support, we need to fake it
         mVSyncThread = new VSyncThread(*this);
     }
+
+    mDimComp = 0;
+    if (mHwc) {
+      mHwc->query(mHwc, HWC_BACKGROUND_LAYER_SUPPORTED, &mDimComp);
+    }
 }
 
 HWComposer::~HWComposer() {
@@ -1000,6 +1005,10 @@ public:
             getLayer()->flags &= ~HWC_SKIP_LAYER;
         }
     }
+    virtual void setDim() {
+        setSkip(false);
+        getLayer()->flags |= 0x80000000;
+    }
     virtual void setIsCursorLayerHint(bool isCursor) {
         if (hwcHasApiVersion(mHwc, HWC_DEVICE_API_VERSION_1_4)) {
             if (isCursor) {

services/surfaceflinger/DisplayHardware/HWComposer.h

@@ -120,6 +120,9 @@ public:
     // does this display have layers handled by GLES
     bool hasGlesComposition(int32_t id) const;
 
+    // does this display support dim layer composition
+    bool hasDimComposition() const { return (mDimComp == 1); }
+
     // get the releaseFence file descriptor for a display's framebuffer layer.
     // the release fence is only valid after commit()
     sp<Fence> getAndResetReleaseFence(int32_t id);
@@ -165,6 +168,7 @@ public:
         virtual sp<Fence> getAndResetReleaseFence() = 0;
         virtual void setDefaultState() = 0;
         virtual void setSkip(bool skip) = 0;
+        virtual void setDim() = 0;
         virtual void setIsCursorLayerHint(bool isCursor = true) = 0;
         virtual void setBlending(uint32_t blending) = 0;
         virtual void setTransform(uint32_t transform) = 0;
@@ -379,6 +383,8 @@ private:
 
     // thread-safe
     mutable Mutex mEventControlLock;
+
+    int mDimComp;
 };
 
 // ---------------------------------------------------------------------------

services/surfaceflinger/Layer.h

@@ -205,7 +205,7 @@ public:
 
     void setGeometry(const sp<const DisplayDevice>& hw,
             HWComposer::HWCLayerInterface& layer);
-    void setPerFrameData(const sp<const DisplayDevice>& hw,
+    virtual void setPerFrameData(const sp<const DisplayDevice>& hw,
             HWComposer::HWCLayerInterface& layer);
     void setAcquireFence(const sp<const DisplayDevice>& hw,
             HWComposer::HWCLayerInterface& layer);

services/surfaceflinger/LayerDim.cpp

@@ -58,6 +58,15 @@ bool LayerDim::isVisible() const {
     return !(s.flags & layer_state_t::eLayerHidden) && s.alpha;
 }
 
+void LayerDim::setPerFrameData(const sp<const DisplayDevice>& hw,
+        HWComposer::HWCLayerInterface& layer) {
+  HWComposer& hwc = mFlinger->getHwComposer();
+
+  Layer::setPerFrameData(hw, layer);
+  if (hwc.hasDimComposition()) {
+    layer.setDim();
+  }
+}
 
 // ---------------------------------------------------------------------------
 

services/surfaceflinger/LayerDim.h

@@ -40,6 +40,8 @@ public:
     virtual bool isSecure() const         { return false; }
     virtual bool isFixedSize() const      { return true; }
     virtual bool isVisible() const;
+    virtual void setPerFrameData(const sp<const DisplayDevice>& hw,
+            HWComposer::HWCLayerInterface& layer);
 };
 
 // ---------------------------------------------------------------------------

services/surfaceflinger/SurfaceFlinger.h

@@ -140,6 +140,7 @@ private:
     friend class Client;
     friend class DisplayEventConnection;
     friend class Layer;
+    friend class LayerDim;
     friend class MonitoredProducer;
 
     // This value is specified in number of frames.  Log frame stats at most