chromeos: Turn off displays on suspend

To handle lucid sleep (where we need to silently resume the system), turn
off the displays on suspend. This also removes the delay for restoring the
display state added in "On resume perform a delayed call to
SetDisplayPower()" According to the bug for that change, it didn't seem to
help with the issue anyways.

BUG=535021
TEST=suspend/resume of various cros platforms with/without external monitor
connected

Review URL: https://codereview.chromium.org/1861593002

Cr-Commit-Position: refs/heads/master@{#389875}

ui/display/chromeos/display_configurator.cc

@@ -35,12 +35,6 @@ typedef std::vector<const DisplayMode*> DisplayModeList;
 // |configure_timer_|.
 const int kConfigureDelayMs = 500;
 
-// The delay spent before reading the display configuration after coming out of
-// suspend. While coming out of suspend the display state may be updating. This
-// is used to wait until the hardware had a chance to update the display state
-// such that we read an up to date state.
-const int kResumeDelayMs = 500;
-
 // The EDID specification marks the top bit of the manufacturer id as reserved.
 const int16_t kReservedManufacturerID = static_cast<int16_t>(1 << 15);
 
@@ -476,8 +470,9 @@ DisplayConfigurator::DisplayConfigurator()
       current_power_state_(chromeos::DISPLAY_POWER_ALL_ON),
       requested_display_state_(MULTIPLE_DISPLAY_STATE_INVALID),
       requested_power_state_(chromeos::DISPLAY_POWER_ALL_ON),
-      requested_power_state_change_(false),
-      requested_power_flags_(kSetDisplayPowerNoFlags),
+      pending_power_state_(chromeos::DISPLAY_POWER_ALL_ON),
+      has_pending_power_state_(false),
+      pending_power_flags_(kSetDisplayPowerNoFlags),
       force_configure_(false),
       next_display_protection_client_id_(1),
       display_externally_controlled_(false),
@@ -844,6 +839,24 @@ void DisplayConfigurator::PrepareForExit() {
   configure_display_ = false;
 }
 
+void DisplayConfigurator::SetDisplayPowerInternal(
+    chromeos::DisplayPowerState power_state,
+    int flags,
+    const ConfigurationCallback& callback) {
+  if (power_state == current_power_state_ &&
+      !(flags & kSetDisplayPowerForceProbe)) {
+    callback.Run(true);
+    return;
+  }
+
+  pending_power_state_ = power_state;
+  has_pending_power_state_ = true;
+  pending_power_flags_ = flags;
+  queued_configuration_callbacks_.push_back(callback);
+
+  RunPendingConfiguration();
+}
+
 void DisplayConfigurator::SetDisplayPower(
     chromeos::DisplayPowerState power_state,
     int flags,
@@ -857,18 +870,9 @@ void DisplayConfigurator::SetDisplayPower(
           << DisplayPowerStateToString(power_state) << " flags=" << flags
           << ", configure timer="
           << (configure_timer_.IsRunning() ? "Running" : "Stopped");
-  if (power_state == requested_power_state_ &&
-      !(flags & kSetDisplayPowerForceProbe)) {
-    callback.Run(true);
-    return;
-  }
 
   requested_power_state_ = power_state;
-  requested_power_state_change_ = true;
-  requested_power_flags_ = flags;
-  queued_configuration_callbacks_.push_back(callback);
-
-  RunPendingConfiguration();
+  SetDisplayPowerInternal(requested_power_state_, flags, callback);
 }
 
 void DisplayConfigurator::SetDisplayMode(MultipleDisplayState new_state) {
@@ -931,21 +935,9 @@ void DisplayConfigurator::RemoveObserver(Observer* observer) {
 
 void DisplayConfigurator::SuspendDisplays(
     const ConfigurationCallback& callback) {
-  // If the display is off due to user inactivity and there's only a single
-  // internal display connected, switch to the all-on state before
-  // suspending.  This shouldn't be very noticeable to the user since the
-  // backlight is off at this point, and doing this lets us resume directly
-  // into the "on" state, which greatly reduces resume times.
-  if (requested_power_state_ == chromeos::DISPLAY_POWER_ALL_OFF) {
-    SetDisplayPower(chromeos::DISPLAY_POWER_ALL_ON,
-                    kSetDisplayPowerOnlyIfSingleInternalDisplay, callback);
-
-    // We need to make sure that the monitor configuration we just did actually
-    // completes before we return, because otherwise the X message could be
-    // racing with the HandleSuspendReadiness message.
-    native_display_delegate_->SyncWithServer();
-  } else {
-    callback.Run(true);
+  if (!configure_display_ || display_externally_controlled_) {
+    callback.Run(false);
+    return;
   }
 
   displays_suspended_ = true;
@@ -953,16 +945,29 @@ void DisplayConfigurator::SuspendDisplays(
   // Stop |configure_timer_| because we will force probe and configure all the
   // displays at resume time anyway.
   configure_timer_.Stop();
+
+  // Turn off the displays for suspend. This way, if we wake up for lucid sleep,
+  // the displays will not turn on (all displays should be off for lucid sleep
+  // unless explicitly requested by lucid sleep code). Use
+  // SetDisplayPowerInternal so requested_power_state_ is maintained.
+  SetDisplayPowerInternal(chromeos::DISPLAY_POWER_ALL_OFF,
+                          kSetDisplayPowerNoFlags, callback);
+
+  // We need to make sure that the monitor configuration we just did actually
+  // completes before we return.
+  native_display_delegate_->SyncWithServer();
 }
 
 void DisplayConfigurator::ResumeDisplays() {
+  if (!configure_display_ || display_externally_controlled_)
+    return;
+
   displays_suspended_ = false;
 
-  configure_timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromMilliseconds(kResumeDelayMs),
-      base::Bind(&DisplayConfigurator::RestoreRequestedPowerStateAfterResume,
-                 base::Unretained(this)));
+  // If requested_power_state_ is ALL_OFF due to idle suspend, powerd will turn
+  // the display power on when it enables the backlight.
+  SetDisplayPower(requested_power_state_, kSetDisplayPowerNoFlags,
+                  base::Bind(&DoNothing));
 }
 
 void DisplayConfigurator::ConfigureDisplays() {
@@ -988,7 +993,7 @@ void DisplayConfigurator::RunPendingConfiguration() {
 
   configuration_task_.reset(new UpdateDisplayConfigurationTask(
       native_display_delegate_.get(), layout_manager_.get(),
-      requested_display_state_, requested_power_state_, requested_power_flags_,
+      requested_display_state_, pending_power_state_, pending_power_flags_,
       0, force_configure_, base::Bind(&DisplayConfigurator::OnConfigured,
                                       weak_ptr_factory_.GetWeakPtr())));
   configuration_task_->set_virtual_display_snapshots(
@@ -997,8 +1002,8 @@ void DisplayConfigurator::RunPendingConfiguration() {
   // Reset the flags before running the task; otherwise it may end up scheduling
   // another configuration.
   force_configure_ = false;
-  requested_power_flags_ = kSetDisplayPowerNoFlags;
-  requested_power_state_change_ = false;
+  pending_power_flags_ = kSetDisplayPowerNoFlags;
+  has_pending_power_state_ = false;
   requested_display_state_ = MULTIPLE_DISPLAY_STATE_INVALID;
 
   DCHECK(in_progress_configuration_callbacks_.empty());
@@ -1034,12 +1039,12 @@ void DisplayConfigurator::OnConfigured(
     if (!framebuffer_size.IsEmpty())
       framebuffer_size_ = framebuffer_size;
 
-    // If the requested power state hasn't changed then make sure that value
+    // If the pending power state hasn't changed then make sure that value
     // gets updated as well since the last requested value may have been
     // dependent on certain conditions (ie: if only the internal monitor was
     // present).
-    if (!requested_power_state_change_)
-      requested_power_state_ = new_power_state;
+    if (!has_pending_power_state_)
+      pending_power_state_ = new_power_state;
 
     if (old_power_state != current_power_state_)
       NotifyPowerStateObservers();
@@ -1072,7 +1077,7 @@ bool DisplayConfigurator::ShouldRunConfigurationTask() const {
     return true;
 
   // Schedule if there is a request to change the power state.
-  if (requested_power_state_change_)
+  if (has_pending_power_state_)
     return true;
 
   return false;
@@ -1092,13 +1097,6 @@ void DisplayConfigurator::CallAndClearQueuedCallbacks(bool success) {
   queued_configuration_callbacks_.clear();
 }
 
-void DisplayConfigurator::RestoreRequestedPowerStateAfterResume() {
-  // Force probing to ensure that we pick up any changes that were made while
-  // the system was suspended.
-  SetDisplayPower(requested_power_state_, kSetDisplayPowerForceProbe,
-                  base::Bind(&DoNothing));
-}
-
 void DisplayConfigurator::NotifyDisplayStateObservers(
     bool success,
     MultipleDisplayState attempted_state) {

ui/display/chromeos/display_configurator.h

@@ -300,13 +300,15 @@ class DISPLAY_EXPORT DisplayConfigurator : public NativeDisplayObserver {
   typedef std::map<ContentProtectionClientId, ContentProtections>
       ProtectionRequests;
 
+  // Updates |pending_*| members and applies the passed-in state. |callback| is
+  // invoked (perhaps synchronously) on completion.
+  void SetDisplayPowerInternal(chromeos::DisplayPowerState power_state,
+                               int flags,
+                               const ConfigurationCallback& callback);
+
   // Configures displays. Invoked by |configure_timer_|.
   void ConfigureDisplays();
 
-  // Restores |requested_power_state_| after the system has resumed,
-  // additionally forcing a probe. Invoked by |configure_timer_|.
-  void RestoreRequestedPowerStateAfterResume();
-
   // Notifies observers about an attempted state change.
   void NotifyDisplayStateObservers(bool success,
                                    MultipleDisplayState attempted_state);
@@ -394,11 +396,15 @@ class DISPLAY_EXPORT DisplayConfigurator : public NativeDisplayObserver {
   // Stores the requested power state.
   chromeos::DisplayPowerState requested_power_state_;
 
-  // True if |requested_power_state_| has been changed due to a user request.
-  bool requested_power_state_change_;
+  // The power state used by RunPendingConfiguration(). May be
+  // |requested_power_state_| or DISPLAY_POWER_ALL_OFF for suspend.
+  chromeos::DisplayPowerState pending_power_state_;
+
+  // True if |pending_power_state_| has been changed.
+  bool has_pending_power_state_;
 
   // Bitwise-or value of the |kSetDisplayPower*| flags defined above.
-  int requested_power_flags_;
+  int pending_power_flags_;
 
   // List of callbacks from callers waiting for the display configuration to
   // start/finish. Note these callbacks belong to the pending request, not a