Add support for sending VSYNC events to the framework

use gui/DisplayEvent to receive the events. Events are
dispatched through a unix pipe, so the API is compatible
with utils/Looper. see gui/DisplayEvent.h for more info.

Bug: 1475048
Change-Id: Ia720f64d1b950328b47b22c6a86042e481d35f09

1 files changed, 32 insertions, 0 deletions

diff --git a/libs/gui/ISurfaceComposer.cpp b/libs/gui/ISurfaceComposer.cpp
index 86bc62aa28..db3282781a 100644
--- a/libs/gui/ISurfaceComposer.cpp
+++ b/libs/gui/ISurfaceComposer.cpp
@@ -29,6 +29,9 @@
 
 #include <surfaceflinger/ISurfaceComposer.h>
 
+#include <gui/BitTube.h>
+#include <gui/IDisplayEventConnection.h>
+
 #include <ui/DisplayInfo.h>
 
 #include <gui/ISurfaceTexture.h>
@@ -44,6 +47,8 @@
 
 namespace android {
 
+class IDisplayEventConnection;
+
 class BpSurfaceComposer : public BpInterface<ISurfaceComposer>
 {
 public:
@@ -174,6 +179,27 @@ public:
         }
         return result != 0;
     }
+
+    virtual sp<IDisplayEventConnection> createDisplayEventConnection()
+    {
+        Parcel data, reply;
+        sp<IDisplayEventConnection> result;
+        int err = data.writeInterfaceToken(
+                ISurfaceComposer::getInterfaceDescriptor());
+        if (err != NO_ERROR) {
+            return result;
+        }
+        err = remote()->transact(
+                BnSurfaceComposer::CREATE_DISPLAY_EVENT_CONNECTION,
+                data, &reply);
+        if (err != NO_ERROR) {
+            LOGE("ISurfaceComposer::createDisplayEventConnection: error performing "
+                    "transaction: %s (%d)", strerror(-err), -err);
+            return result;
+        }
+        result = interface_cast<IDisplayEventConnection>(reply.readStrongBinder());
+        return result;
+    }
 };
 
 IMPLEMENT_META_INTERFACE(SurfaceComposer, "android.ui.ISurfaceComposer");
@@ -254,6 +280,12 @@ status_t BnSurfaceComposer::onTransact(
             int32_t result = authenticateSurfaceTexture(surfaceTexture) ? 1 : 0;
             reply->writeInt32(result);
         } break;
+        case CREATE_DISPLAY_EVENT_CONNECTION: {
+            CHECK_INTERFACE(ISurfaceComposer, data, reply);
+            sp<IDisplayEventConnection> connection(createDisplayEventConnection());
+            reply->writeStrongBinder(connection->asBinder());
+            return NO_ERROR;
+        } break;
         default:
             return BBinder::onTransact(code, data, reply, flags);
     }