[Ozone-DRI] Reuse framebuffer when re-enabling CRTC

ui/ozone/platform/dri/screen_manager_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/ozone/platform/dri/dri_buffer.h"
 #include "ui/ozone/platform/dri/hardware_display_controller.h"
 #include "ui/ozone/platform/dri/screen_manager.h"
 #include "ui/ozone/platform/dri/test/mock_dri_wrapper.h"
 
@@ skipping 121 matching lines @@
   EXPECT_FALSE(controller);
 }
 
 TEST_F(ScreenManagerTest, CheckDuplicateConfiguration) {
   screen_manager_->AddDisplayController(dri_.get(), kPrimaryCrtc,
                                         kPrimaryConnector);
   screen_manager_->ConfigureDisplayController(kPrimaryCrtc,
                                               kPrimaryConnector,
                                               GetPrimaryBounds().origin(),
                                               kDefaultMode);
+  uint32_t framebuffer = dri_->current_framebuffer();
+
   screen_manager_->ConfigureDisplayController(kPrimaryCrtc,
                                               kPrimaryConnector,
                                               GetPrimaryBounds().origin(),
                                               kDefaultMode);
 
+  // Should reuse existing framebuffer.
+  EXPECT_EQ(framebuffer, dri_->current_framebuffer());
+
   EXPECT_TRUE(screen_manager_->GetDisplayController(GetPrimaryBounds()));
   EXPECT_FALSE(screen_manager_->GetDisplayController(GetSecondaryBounds()));
 }
 
 TEST_F(ScreenManagerTest, CheckChangingMode) {
   screen_manager_->AddDisplayController(dri_.get(), kPrimaryCrtc,
                                         kPrimaryConnector);
   screen_manager_->ConfigureDisplayController(kPrimaryCrtc,
                                               kPrimaryConnector,
                                               GetPrimaryBounds().origin(),
@@ skipping 111 matching lines @@
   drmModeModeInfo new_mode = kDefaultMode;
   new_mode.vdisplay = 10;
   // Shouldn't enter mirror mode unless the display bounds are the same.
   screen_manager_->ConfigureDisplayController(
       kSecondaryCrtc, kSecondaryConnector, GetPrimaryBounds().origin(),
       new_mode);
 
   EXPECT_FALSE(
       screen_manager_->GetDisplayController(GetPrimaryBounds())->IsMirrored());
 }
+
+TEST_F(ScreenManagerTest, ReuseFramebufferIfDisabledThenReEnabled) {
+  screen_manager_->AddDisplayController(dri_.get(), kPrimaryCrtc,
+                                        kPrimaryConnector);
+  screen_manager_->ConfigureDisplayController(kPrimaryCrtc, kPrimaryConnector,
+                                              GetPrimaryBounds().origin(),
+                                              kDefaultMode);
+  uint32_t framebuffer = dri_->current_framebuffer();
+
+  screen_manager_->DisableDisplayController(kPrimaryCrtc);
+  EXPECT_EQ(0u, dri_->current_framebuffer());
+
+  screen_manager_->ConfigureDisplayController(kPrimaryCrtc, kPrimaryConnector,
+                                              GetPrimaryBounds().origin(),
+                                              kDefaultMode);
+
+  // Should reuse existing framebuffer.
+  EXPECT_EQ(framebuffer, dri_->current_framebuffer());
+}
+
+TEST_F(ScreenManagerTest, CheckMirrorModeAfterBeginReEnabled) {
+  screen_manager_->AddDisplayController(dri_.get(), kPrimaryCrtc,
+                                        kPrimaryConnector);
+  screen_manager_->ConfigureDisplayController(kPrimaryCrtc, kPrimaryConnector,
+                                              GetPrimaryBounds().origin(),
+                                              kDefaultMode);
+  screen_manager_->DisableDisplayController(kPrimaryCrtc);
+
+  screen_manager_->AddDisplayController(dri_.get(), kSecondaryCrtc,
+                                        kSecondaryConnector);
+  screen_manager_->ConfigureDisplayController(
+      kSecondaryCrtc, kSecondaryConnector, GetPrimaryBounds().origin(),
+      kDefaultMode);
+
+  base::WeakPtr<ui::HardwareDisplayController> controller =
+      screen_manager_->GetDisplayController(GetPrimaryBounds());
+  EXPECT_TRUE(controller);
+  EXPECT_FALSE(controller->IsMirrored());
+
+  screen_manager_->ConfigureDisplayController(kPrimaryCrtc, kPrimaryConnector,
+                                              GetPrimaryBounds().origin(),
+                                              kDefaultMode);
+  EXPECT_TRUE(controller);
+  EXPECT_TRUE(controller->IsMirrored());
+}