fix transition from full overlays to fb

we need to clear the whole framebuffer in that situation because
we can't trust the content of the FB when partial (fb preserving)
updates are used.

Bug: 5318492

Change-Id: I3f0e01b0fb665a34e44d88ad9f0f54a5d990060b

3 files changed, 39 insertions, 1 deletions

diff --git a/services/surfaceflinger/DisplayHardware/DisplayHardware.h b/services/surfaceflinger/DisplayHardware/DisplayHardware.h
index 40a6f1e..f02c954 100644
--- a/services/surfaceflinger/DisplayHardware/DisplayHardware.h
+++ b/services/surfaceflinger/DisplayHardware/DisplayHardware.h
@@ -84,9 +84,10 @@ public:
     
     status_t compositionComplete() const;
     
-    Rect bounds() const {
+    Rect getBounds() const {
         return Rect(mWidth, mHeight);
     }
+    inline Rect bounds() const { return getBounds(); }
 
     // only for debugging
     int getCurrentBufferIndex() const;
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index daefd5e..e707bdc 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -40,6 +40,7 @@ namespace android {
 HWComposer::HWComposer(const sp<SurfaceFlinger>& flinger)
     : mFlinger(flinger),
       mModule(0), mHwc(0), mList(0), mCapacity(0),
+      mNumOVLayers(0), mNumFBLayers(0),
       mDpy(EGL_NO_DISPLAY), mSur(EGL_NO_SURFACE)
 {
     int err = hw_get_module(HWC_HARDWARE_MODULE_ID, &mModule);
@@ -98,9 +99,40 @@ status_t HWComposer::createWorkList(size_t numLayers) {
 
 status_t HWComposer::prepare() const {
     int err = mHwc->prepare(mHwc, mList);
+    if (err == NO_ERROR) {
+        size_t numOVLayers = 0;
+        size_t numFBLayers = 0;
+        size_t count = mList->numHwLayers;
+        for (size_t i=0 ; i<count ; i++) {
+            hwc_layer& l(mList->hwLayers[i]);
+            if (l.flags & HWC_SKIP_LAYER) {
+                l.compositionType = HWC_FRAMEBUFFER;
+            }
+            switch (l.compositionType) {
+                case HWC_OVERLAY:
+                    numOVLayers++;
+                    break;
+                case HWC_FRAMEBUFFER:
+                    numFBLayers++;
+                    break;
+            }
+        }
+        mNumOVLayers = numOVLayers;
+        mNumFBLayers = numFBLayers;
+    }
     return (status_t)err;
 }
 
+size_t HWComposer::getLayerCount(int type) const {
+    switch (type) {
+        case HWC_OVERLAY:
+            return mNumOVLayers;
+        case HWC_FRAMEBUFFER:
+            return mNumFBLayers;
+    }
+    return 0;
+}
+
 status_t HWComposer::commit() const {
     int err = mHwc->set(mHwc, mDpy, mSur, mList);
     if (mList) {
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index 8758a80..aa8ebe1 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -64,6 +64,9 @@ public:
     size_t getNumLayers() const;
     hwc_layer_t* getLayers() const;
 
+    // updated in preapre()
+    size_t getLayerCount(int type) const;
+
     // for debugging
     void dump(String8& out, char* scratch, size_t SIZE,
             const Vector< sp<LayerBase> >& visibleLayersSortedByZ) const;
@@ -81,6 +84,8 @@ private:
     hwc_composer_device_t*  mHwc;
     hwc_layer_list_t*       mList;
     size_t                  mCapacity;
+    mutable size_t          mNumOVLayers;
+    mutable size_t          mNumFBLayers;
     hwc_display_t           mDpy;
     hwc_surface_t           mSur;
     cb_context              mCBContext;