SurfaceFlinger: send VSYNC power hints to IPowerManager

VSYNC power hints are now sent via binder to IPowerManager.
SurfaceFlinger no longer loads a second copy of the PowerHAL.
VSYNC power hints are sent in batches and not on per frame basis.

Change-Id: Icc2eee5df56135bd24dc244a84e7c12dd5511fec

services/surfaceflinger/Android.mk

@@ -96,7 +96,8 @@ LOCAL_SHARED_LIBRARIES := \
 	libGLESv2 \
 	libbinder \
 	libui \
-	libgui
+	libgui \
+	libpowermanager
 
 LOCAL_MODULE:= libsurfaceflinger
 

services/surfaceflinger/DisplayHardware/PowerHAL.cpp

@@ -20,38 +20,30 @@
 #include <cutils/log.h>
 #include <utils/Errors.h>
 
+#include <binder/IServiceManager.h>
+#include <powermanager/IPowerManager.h>
+#include <powermanager/PowerManager.h>
+
 #include "PowerHAL.h"
 
 namespace android {
 // ---------------------------------------------------------------------------
 
-PowerHAL::PowerHAL() : mPowerModule(0), mVSyncHintEnabled(false) {
-    int err = hw_get_module(POWER_HARDWARE_MODULE_ID,
-            (const hw_module_t **)&mPowerModule);
-    ALOGW_IF(err, "%s module not found", POWER_HARDWARE_MODULE_ID);
-}
-
-PowerHAL::~PowerHAL() {
-}
-
-status_t PowerHAL::initCheck() const {
-    return mPowerModule ? NO_ERROR : NO_INIT;
-}
-
 status_t PowerHAL::vsyncHint(bool enabled) {
-    if (!mPowerModule) {
-        return NO_INIT;
-    }
-    if (mPowerModule->common.module_api_version >= POWER_MODULE_API_VERSION_0_2) {
-        if (mPowerModule->powerHint) {
-            if (mVSyncHintEnabled != bool(enabled)) {
-                mPowerModule->powerHint(mPowerModule,
-                        POWER_HINT_VSYNC, (void*)enabled);
-                mVSyncHintEnabled = bool(enabled);
-            }
+    Mutex::Autolock _l(mlock);
+    if (mPowerManager == NULL) {
+        const String16 serviceName("power");
+        sp<IBinder> bs = defaultServiceManager()->checkService(serviceName);
+        if (bs == NULL) {
+            return NAME_NOT_FOUND;
         }
+        mPowerManager = interface_cast<IPowerManager>(bs);
     }
-    return NO_ERROR;
+    status_t status = mPowerManager->powerHint(POWER_HINT_VSYNC, enabled ? 1 : 0);
+    if(status == DEAD_OBJECT) {
+        mPowerManager = NULL;
+    }
+    return status;
 }
 
 // ---------------------------------------------------------------------------

services/surfaceflinger/DisplayHardware/PowerHAL.h

@@ -19,7 +19,9 @@
 
 #include <stdint.h>
 #include <sys/types.h>
+#include <utils/Mutex.h>
 
+#include <powermanager/IPowerManager.h>
 #include <hardware/power.h>
 
 namespace android {
@@ -28,15 +30,11 @@ namespace android {
 class PowerHAL
 {
 public:
-    PowerHAL();
-    ~PowerHAL();
-
-    status_t initCheck() const;
     status_t vsyncHint(bool enabled);
 
 private:
-    power_module_t*   mPowerModule;
-    bool mVSyncHintEnabled;
+    sp<IPowerManager> mPowerManager;
+    Mutex mlock;
 };
 
 // ---------------------------------------------------------------------------

services/surfaceflinger/EventThread.cpp

@@ -35,12 +35,21 @@
 // ---------------------------------------------------------------------------
 namespace android {
 // ---------------------------------------------------------------------------
+// time to wait between VSYNC requests before sending a VSYNC OFF power hint: 40msec.
+const long vsyncHintOffDelay = 40000000;
+
+static void vsyncOffCallback(union sigval val) {
+    EventThread *ev = (EventThread *)val.sival_ptr;
+    ev->sendVsyncHintOff();
+    return;
+}
 
 EventThread::EventThread(const sp<VSyncSource>& src)
     : mVSyncSource(src),
       mUseSoftwareVSync(false),
       mVsyncEnabled(false),
-      mDebugVsyncEnabled(false) {
+      mDebugVsyncEnabled(false),
+      mVsyncHintSent(false) {
 
     for (int32_t i=0 ; i<DisplayDevice::NUM_BUILTIN_DISPLAY_TYPES ; i++) {
         mVSyncEvent[i].header.type = DisplayEventReceiver::DISPLAY_EVENT_VSYNC;
@@ -48,6 +57,31 @@ EventThread::EventThread(const sp<VSyncSource>& src)
         mVSyncEvent[i].header.timestamp = 0;
         mVSyncEvent[i].vsync.count =  0;
     }
+    struct sigevent se;
+    se.sigev_notify = SIGEV_THREAD;
+    se.sigev_value.sival_ptr = this;
+    se.sigev_notify_function = vsyncOffCallback;
+    se.sigev_notify_attributes = NULL;
+    timer_create(CLOCK_MONOTONIC, &se, &mTimerId);
+}
+
+void EventThread::sendVsyncHintOff() {
+    Mutex::Autolock _l(mLock);
+    mPowerHAL.vsyncHint(false);
+    mVsyncHintSent = false;
+}
+
+void EventThread::sendVsyncHintOnLocked() {
+    struct itimerspec ts;
+    if(!mVsyncHintSent) {
+        mPowerHAL.vsyncHint(true);
+        mVsyncHintSent = true;
+    }
+    ts.it_value.tv_sec = 0;
+    ts.it_value.tv_nsec = vsyncHintOffDelay;
+    ts.it_interval.tv_sec = 0;
+    ts.it_interval.tv_nsec = 0;
+    timer_settime(mTimerId, 0, &ts, NULL);
 }
 
 void EventThread::onFirstRef() {
@@ -307,17 +341,16 @@ void EventThread::enableVSyncLocked() {
             mVsyncEnabled = true;
             mVSyncSource->setCallback(static_cast<VSyncSource::Callback*>(this));
             mVSyncSource->setVSyncEnabled(true);
-            mPowerHAL.vsyncHint(true);
         }
     }
     mDebugVsyncEnabled = true;
+    sendVsyncHintOnLocked();
 }
 
 void EventThread::disableVSyncLocked() {
     if (mVsyncEnabled) {
         mVsyncEnabled = false;
         mVSyncSource->setVSyncEnabled(false);
-        mPowerHAL.vsyncHint(false);
         mDebugVsyncEnabled = false;
     }
 }

services/surfaceflinger/EventThread.h

@@ -97,6 +97,7 @@ public:
             DisplayEventReceiver::Event* event);
 
     void dump(String8& result) const;
+    void sendVsyncHintOff();
 
 private:
     virtual bool        threadLoop();
@@ -107,6 +108,7 @@ private:
     void removeDisplayEventConnection(const wp<Connection>& connection);
     void enableVSyncLocked();
     void disableVSyncLocked();
+    void sendVsyncHintOnLocked();
 
     // constants
     sp<VSyncSource> mVSyncSource;
@@ -124,6 +126,9 @@ private:
 
     // for debugging
     bool mDebugVsyncEnabled;
+
+    bool mVsyncHintSent;
+    timer_t mTimerId;
 };
 
 // ---------------------------------------------------------------------------