hwc: Do not compose when there is no update in Frame content
No need to blit layers when there is no change in content in successive
frames, so we can avoid those blits to achieve power and performance
improvements. For example screen-refresh triggered by pp-daemon.
Change-Id: Ie992705fa3d7f1ceba3d55b4865b017cfeafb34f
diff --git a/libhwcomposer/hwc_copybit.h b/libhwcomposer/hwc_copybit.h
index 4223aa0..993c790 100644
--- a/libhwcomposer/hwc_copybit.h
+++ b/libhwcomposer/hwc_copybit.h
@@ -28,6 +28,8 @@
#define MAX_SCALE_FACTOR 16
#define MIN_SCALE_FACTOR 0.0625
#define MAX_LAYERS_FOR_ABC 2
+#define INVALID_DIMENSION -1
+#define NO_UPDATING_LAYER -2
namespace qhwc {
class CopyBit {