From 118b5d7961a4abc29c8bd592956007f40ad4fc6d Mon Sep 17 00:00:00 2001
From: Jean-Baptiste Queru <jbq@google.com>
Date: Thu, 14 Oct 2010 18:04:30 -0700
Subject: [PATCH] Allow disabling page-flipping.

Some devices have low-level bugs in their page-flip.

Disabling it at this level gives us more flexibility
than trying to control it elsewhere.

Bug: 3097357
Change-Id: Icc6ae172264e453bec0680e74a497a2b24299c4a
---
 modules/gralloc/Android.mk      | 4 ++++
 modules/gralloc/framebuffer.cpp | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/modules/gralloc/Android.mk b/modules/gralloc/Android.mk
index 8946fac..ac09e5a 100644
--- a/modules/gralloc/Android.mk
+++ b/modules/gralloc/Android.mk
@@ -29,4 +29,8 @@ LOCAL_SRC_FILES := 	\
 	
 LOCAL_MODULE := gralloc.default
 LOCAL_CFLAGS:= -DLOG_TAG=\"gralloc\"
+ifeq ($(BOARD_NO_PAGE_FLIPPING),true)
+LOCAL_CFLAGS += -DNO_PAGE_FLIPPING
+endif
+
 include $(BUILD_SHARED_LIBRARY)
diff --git a/modules/gralloc/framebuffer.cpp b/modules/gralloc/framebuffer.cpp
index 0195103..a487b5d 100644
--- a/modules/gralloc/framebuffer.cpp
+++ b/modules/gralloc/framebuffer.cpp
@@ -43,7 +43,12 @@
 /*****************************************************************************/
 
 // numbers of buffers for page flipping
+#if defined(NO_PAGE_FLIPPING)
+// page-flipping is buggy on some devices
+#define NUM_BUFFERS 1
+#else
 #define NUM_BUFFERS 2
+#endif
 
 
 enum {
-- 
2.11.0