Make Hardware Display Controller enable state dependent on its CRTCs.

1. Change is_disabled variables in CRTC Controller and Hardware Display
Controller to positive connotation(is_enabled).
2. HDC doesn't have its own enable state now; instead, it checks the states of
all CRTC controllers it manages.

BUG=b/172069469
TEST=ozone_unittests, modesetting and disabling an external  monitor

Change-Id: I0f613616ef4dd219298432904c4acabf5f5335ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2510690
Commit-Queue: Mark Yacoub <markyacoub@google.com>
Reviewed-by: Daniel Nicoara <dnicoara@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823165}

ui/ozone/platform/drm/gpu/crtc_controller.cc

@@ -27,7 +27,7 @@ CrtcController::CrtcController(const scoped_refptr<DrmDevice>& drm,
       state_(drm->plane_manager()->GetCrtcStateForCrtcId(crtc)) {}
 
 CrtcController::~CrtcController() {
-  if (!is_disabled()) {
+  if (is_enabled()) {
     const std::vector<std::unique_ptr<HardwareDisplayPlane>>& all_planes =
         drm_->plane_manager()->planes();
     for (const auto& plane : all_planes) {
@@ -51,7 +51,7 @@ bool CrtcController::AssignOverlayPlanes(HardwareDisplayPlaneList* plane_list,
                                          bool is_modesetting) {
   // If we're in the process of modesetting, the CRTC is still disabled.
   // Once the modeset is done, we expect it to be enabled.
-  DCHECK(is_modesetting || !is_disabled());
+  DCHECK(is_modesetting || is_enabled());
 
   const DrmOverlayPlane* primary = DrmOverlayPlane::GetPrimaryPlane(overlays);
   if (primary &&
@@ -76,7 +76,7 @@ std::vector<uint64_t> CrtcController::GetFormatModifiers(uint32_t format) {
 }
 
 void CrtcController::SetCursor(uint32_t handle, const gfx::Size& size) {
-  if (is_disabled())
+  if (!is_enabled())
     return;
   if (!drm_->SetCursor(crtc_, handle, size)) {
     PLOG(ERROR) << "drmModeSetCursor: device " << drm_->device_path().value()
@@ -86,7 +86,7 @@ void CrtcController::SetCursor(uint32_t handle, const gfx::Size& size) {
 }
 
 void CrtcController::MoveCursor(const gfx::Point& location) {
-  if (is_disabled())
+  if (!is_enabled())
     return;
   drm_->MoveCursor(crtc_, location);
 }

ui/ozone/platform/drm/gpu/crtc_controller.h

@@ -38,7 +38,7 @@ class CrtcController {
   uint32_t crtc() const { return crtc_; }
   uint32_t connector() const { return connector_; }
   const scoped_refptr<DrmDevice>& drm() const { return drm_; }
-  bool is_disabled() const { return !state_.properties.active.value; }
+  bool is_enabled() const { return state_.properties.active.value; }
 
   bool AssignOverlayPlanes(HardwareDisplayPlaneList* plane_list,
                            const DrmOverlayPlaneList& planes,

ui/ozone/platform/drm/gpu/drm_overlay_validator_unittest.cc

@@ -88,7 +88,7 @@ class DrmOverlayValidatorTest : public testing::Test {
     bool status = drm_->plane_manager()->Commit(std::move(commit_request),
                                                 DRM_MODE_ATOMIC_ALLOW_MODESET);
     controller->UpdateState(
-        /*enabled=*/true,
+        /*enable_requested=*/true,
         ui::DrmOverlayPlane::GetPrimaryPlane(request_for_update[0].overlays()));
 
     return status;

ui/ozone/platform/drm/gpu/hardware_display_controller.cc

@@ -66,7 +66,7 @@ void DrawCursor(DrmDumbBuffer* cursor, const SkBitmap& image) {
 HardwareDisplayController::HardwareDisplayController(
     std::unique_ptr<CrtcController> controller,
     const gfx::Point& origin)
-    : origin_(origin), is_disabled_(controller->is_disabled()) {
+    : origin_(origin) {
   AddCrtc(std::move(controller));
   AllocateCursorBuffers();
 }
@@ -124,14 +124,10 @@ void HardwareDisplayController::GetDisableProps(CommitRequest* commit_request) {
 }
 
 void HardwareDisplayController::UpdateState(
-    bool is_enabled,
+    bool enable_requested,
     const DrmOverlayPlane* primary_plane) {
-  // TODO(markyacoub): Update how we report the controller state. Right now, the
-  // controller state is independent of its CRTCs; however, it should reflect
-  // its CRTCs active states.
-  is_disabled_ = !is_enabled;
-
-  if (is_enabled) {
+  // Verify that the current state matches the requested state.
+  if (enable_requested && IsEnabled()) {
     DCHECK(primary_plane);
     // TODO(markyacoub): This should be absorbed in the commit request.
     ResetCursor();
@@ -182,7 +178,7 @@ bool HardwareDisplayController::ScheduleOrTestPageFlip(
     scoped_refptr<PageFlipRequest> page_flip_request,
     std::unique_ptr<gfx::GpuFence>* out_fence) {
   TRACE_EVENT0("drm", "HDC::SchedulePageFlip");
-  DCHECK(!is_disabled_);
+  DCHECK(IsEnabled());
 
   // Ignore requests with no planes to schedule.
   if (plane_list.empty())
@@ -331,8 +327,13 @@ bool HardwareDisplayController::IsMirrored() const {
   return crtc_controllers_.size() > 1;
 }
 
-bool HardwareDisplayController::IsDisabled() const {
-  return is_disabled_;
+bool HardwareDisplayController::IsEnabled() const {
+  bool is_enabled = true;
+
+  for (const auto& controller : crtc_controllers_)
+    is_enabled &= controller->is_enabled();
+
+  return is_enabled;
 }
 
 gfx::Size HardwareDisplayController::GetModeSize() const {

ui/ozone/platform/drm/gpu/hardware_display_controller.h

@@ -104,7 +104,7 @@ class HardwareDisplayController {
   void GetDisableProps(CommitRequest* commit_request);
 
   // Updates state of the controller after modeset/enable/disable is performed.
-  void UpdateState(bool is_enabled, const DrmOverlayPlane* primary_plane);
+  void UpdateState(bool enable_requested, const DrmOverlayPlane* primary_plane);
 
   // Schedules the |overlays|' framebuffers to be displayed on the next vsync
   // event. The event will be posted on the graphics card file descriptor |fd_|
@@ -152,7 +152,7 @@ class HardwareDisplayController {
       uint32_t crtc);
   bool HasCrtc(const scoped_refptr<DrmDevice>& drm, uint32_t crtc) const;
   bool IsMirrored() const;
-  bool IsDisabled() const;
+  bool IsEnabled() const;
   gfx::Size GetModeSize() const;
 
   gfx::Point origin() const { return origin_; }
@@ -207,8 +207,6 @@ class HardwareDisplayController {
   int cursor_frontbuffer_ = 0;
   DrmDumbBuffer* current_cursor_ = nullptr;
 
-  bool is_disabled_;
-
   base::WeakPtrFactory<HardwareDisplayController> weak_ptr_factory_{this};
 
   DISALLOW_COPY_AND_ASSIGN(HardwareDisplayController);

ui/ozone/platform/drm/gpu/hardware_display_controller_unittest.cc

@@ -250,7 +250,7 @@ bool HardwareDisplayControllerTest::ModesetWithPlane(
   bool status = drm_->plane_manager()->Commit(std::move(commit_request),
                                               DRM_MODE_ATOMIC_ALLOW_MODESET);
   controller_->UpdateState(
-      /*enabled=*/true,
+      /*enable_requested=*/true,
       ui::DrmOverlayPlane::GetPrimaryPlane(request_for_update[0].overlays()));
 
   return status;
@@ -262,7 +262,7 @@ bool HardwareDisplayControllerTest::DisableController() {
   ui::CommitRequest request_for_update = commit_request;
   bool status = drm_->plane_manager()->Commit(std::move(commit_request),
                                               DRM_MODE_ATOMIC_ALLOW_MODESET);
-  controller_->UpdateState(/*enabled=*/false, nullptr);
+  controller_->UpdateState(/*enable_requested=*/false, nullptr);
 
   return status;
 }

ui/ozone/platform/drm/gpu/screen_manager.cc

@@ -315,7 +315,7 @@ void ScreenManager::SetDisplayControllerForEnableAndGetProps(
   // comparison on the mode since the refresh rate may have changed.
   if (SameMode(mode, crtc_controller->mode()) &&
       origin == controller->origin()) {
-    if (controller->IsDisabled()) {
+    if (!controller->IsEnabled()) {
       // Even if there is a mirrored display, Modeset the CRTC with its mode in
       // the original controller so that only this CRTC is affected by the mode.
       // Otherwise it could apply a mode with the same resolution and refresh
@@ -449,7 +449,7 @@ ScreenManager::HardwareDisplayControllers::iterator
 ScreenManager::FindActiveDisplayControllerByLocation(const gfx::Rect& bounds) {
   for (auto it = controllers_.begin(); it != controllers_.end(); ++it) {
     gfx::Rect controller_bounds((*it)->origin(), (*it)->GetModeSize());
-    if (controller_bounds == bounds && !(*it)->IsDisabled())
+    if (controller_bounds == bounds && (*it)->IsEnabled())
       return it;
   }
 
@@ -463,7 +463,7 @@ ScreenManager::FindActiveDisplayControllerByLocation(
   for (auto it = controllers_.begin(); it != controllers_.end(); ++it) {
     gfx::Rect controller_bounds((*it)->origin(), (*it)->GetModeSize());
     if ((*it)->GetDrmDevice() == drm && controller_bounds == bounds &&
-        !(*it)->IsDisabled())
+        (*it)->IsEnabled())
       return it;
   }
 
@@ -475,7 +475,7 @@ void ScreenManager::UpdateControllerToWindowMapping() {
   // First create a unique mapping between a window and a controller. Note, a
   // controller may be associated with at most 1 window.
   for (const auto& controller : controllers_) {
-    if (controller->IsDisabled())
+    if (!controller->IsEnabled())
       continue;
 
     DrmWindow* window = FindWindowAt(