src/ui/display/chromeos/display_configurator.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/display/chromeos/display_configurator.h"
   6
   7 #include "base/bind.h"
   8 #include "base/command_line.h"
   9 #include "base/logging.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/sys_info.h"
  13 #include "base/time/time.h"
  14 #include "ui/display/display_switches.h"
  15 #include "ui/display/types/chromeos/display_mode.h"
  16 #include "ui/display/types/chromeos/display_snapshot.h"
  17 #include "ui/display/types/chromeos/native_display_delegate.h"
  18
  19 namespace ui {
  20
  21 namespace {
  22
  23 typedef std::vector<const DisplayMode*> DisplayModeList;
  24
  25 // The delay to perform configuration after RRNotify. See the comment for
  26 // |configure_timer_|.
  27 const int kConfigureDelayMs = 500;
  28
  29 // The delay spent before reading the display configuration after coming out of
  30 // suspend. While coming out of suspend the display state may be updating. This
  31 // is used to wait until the hardware had a chance to update the display state
  32 // such that we read an up to date state.
  33 const int kResumeDelayMs = 500;
  34
  35 // Returns a string describing |state|.
  36 std::string DisplayPowerStateToString(chromeos::DisplayPowerState state) {
  37   switch (state) {
  38     case chromeos::DISPLAY_POWER_ALL_ON:
  39       return "ALL_ON";
  40     case chromeos::DISPLAY_POWER_ALL_OFF:
  41       return "ALL_OFF";
  42     case chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON:
  43       return "INTERNAL_OFF_EXTERNAL_ON";
  44     case chromeos::DISPLAY_POWER_INTERNAL_ON_EXTERNAL_OFF:
  45       return "INTERNAL_ON_EXTERNAL_OFF";
  46     default:
  47       return "unknown (" + base::IntToString(state) + ")";
  48   }
  49 }
  50
  51 // Returns a string describing |state|.
  52 std::string DisplayStateToString(MultipleDisplayState state) {
  53   switch (state) {
  54     case MULTIPLE_DISPLAY_STATE_INVALID:
  55       return "INVALID";
  56     case MULTIPLE_DISPLAY_STATE_HEADLESS:
  57       return "HEADLESS";
  58     case MULTIPLE_DISPLAY_STATE_SINGLE:
  59       return "SINGLE";
  60     case MULTIPLE_DISPLAY_STATE_DUAL_MIRROR:
  61       return "DUAL_MIRROR";
  62     case MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED:
  63       return "DUAL_EXTENDED";
  64   }
  65   NOTREACHED() << "Unknown state " << state;
  66   return "INVALID";
  67 }
  68
  69 // Returns the number of displays in |displays| that should be turned on, per
  70 // |state|.  If |display_power| is non-NULL, it is updated to contain the
  71 // on/off state of each corresponding entry in |displays|.
  72 int GetDisplayPower(
  73     const std::vector<DisplayConfigurator::DisplayState>& display_states,
  74     chromeos::DisplayPowerState state,
  75     std::vector<bool>* display_power) {
  76   int num_on_displays = 0;
  77   if (display_power)
  78     display_power->resize(display_states.size());
  79
  80   for (size_t i = 0; i < display_states.size(); ++i) {
  81     bool internal =
  82         display_states[i].display->type() == DISPLAY_CONNECTION_TYPE_INTERNAL;
  83     bool on =
  84         state == chromeos::DISPLAY_POWER_ALL_ON ||
  85         (state == chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON &&
  86          !internal) ||
  87         (state == chromeos::DISPLAY_POWER_INTERNAL_ON_EXTERNAL_OFF && internal);
  88     if (display_power)
  89       (*display_power)[i] = on;
  90     if (on)
  91       num_on_displays++;
  92   }
  93   return num_on_displays;
  94 }
  95
  96 }  // namespace
  97
  98
  99 const int DisplayConfigurator::kSetDisplayPowerNoFlags = 0;
 100 const int DisplayConfigurator::kSetDisplayPowerForceProbe = 1 << 0;
 101 const int
 102 DisplayConfigurator::kSetDisplayPowerOnlyIfSingleInternalDisplay = 1 << 1;
 103
 104 DisplayConfigurator::DisplayState::DisplayState()
 105     : display(NULL),
 106       touch_device_id(0),
 107       selected_mode(NULL),
 108       mirror_mode(NULL) {}
 109
 110 bool DisplayConfigurator::TestApi::TriggerConfigureTimeout() {
 111   if (configurator_->configure_timer_.IsRunning()) {
 112     configurator_->configure_timer_.user_task().Run();
 113     configurator_->configure_timer_.Stop();
 114     return true;
 115   } else {
 116     return false;
 117   }
 118 }
 119
 120 // static
 121 const DisplayMode* DisplayConfigurator::FindDisplayModeMatchingSize(
 122     const DisplaySnapshot& display,
 123     const gfx::Size& size) {
 124   const DisplayMode* best_mode = NULL;
 125   for (DisplayModeList::const_iterator it = display.modes().begin();
 126        it != display.modes().end();
 127        ++it) {
 128     const DisplayMode* mode = *it;
 129
 130     if (mode->size() != size)
 131       continue;
 132
 133     if (!best_mode) {
 134       best_mode = mode;
 135       continue;
 136     }
 137
 138     if (mode->is_interlaced()) {
 139       if (!best_mode->is_interlaced())
 140         continue;
 141     } else {
 142       // Reset the best rate if the non interlaced is
 143       // found the first time.
 144       if (best_mode->is_interlaced()) {
 145         best_mode = mode;
 146         continue;
 147       }
 148     }
 149     if (mode->refresh_rate() < best_mode->refresh_rate())
 150       continue;
 151
 152     best_mode = mode;
 153   }
 154
 155   return best_mode;
 156 }
 157
 158 DisplayConfigurator::DisplayConfigurator()
 159     : state_controller_(NULL),
 160       mirroring_controller_(NULL),
 161       is_panel_fitting_enabled_(false),
 162       configure_display_(base::SysInfo::IsRunningOnChromeOS()),
 163       display_state_(MULTIPLE_DISPLAY_STATE_INVALID),
 164       power_state_(chromeos::DISPLAY_POWER_ALL_ON),
 165       next_display_protection_client_id_(1) {}
 166
 167 DisplayConfigurator::~DisplayConfigurator() {
 168   if (native_display_delegate_)
 169     native_display_delegate_->RemoveObserver(this);
 170 }
 171
 172 void DisplayConfigurator::SetDelegatesForTesting(
 173     scoped_ptr<NativeDisplayDelegate> display_delegate,
 174     scoped_ptr<TouchscreenDelegate> touchscreen_delegate) {
 175   DCHECK(!native_display_delegate_);
 176   DCHECK(!touchscreen_delegate_);
 177
 178   native_display_delegate_ = display_delegate.Pass();
 179   touchscreen_delegate_ = touchscreen_delegate.Pass();
 180   configure_display_ = true;
 181 }
 182
 183 void DisplayConfigurator::SetInitialDisplayPower(
 184     chromeos::DisplayPowerState power_state) {
 185   DCHECK_EQ(display_state_, MULTIPLE_DISPLAY_STATE_INVALID);
 186   power_state_ = power_state;
 187 }
 188
 189 void DisplayConfigurator::Init(bool is_panel_fitting_enabled) {
 190   is_panel_fitting_enabled_ = is_panel_fitting_enabled;
 191   if (!configure_display_)
 192     return;
 193
 194   // If the delegates are already initialized don't update them (For example,
 195   // tests set their own delegates).
 196   if (!native_display_delegate_) {
 197     native_display_delegate_ = CreatePlatformNativeDisplayDelegate();
 198     native_display_delegate_->AddObserver(this);
 199   }
 200
 201   if (!touchscreen_delegate_)
 202     touchscreen_delegate_ = CreatePlatformTouchscreenDelegate();
 203 }
 204
 205 void DisplayConfigurator::ForceInitialConfigure(
 206     uint32_t background_color_argb) {
 207   if (!configure_display_)
 208     return;
 209
 210   native_display_delegate_->GrabServer();
 211   native_display_delegate_->Initialize();
 212
 213   UpdateCachedDisplays();
 214   if (cached_displays_.size() > 1 && background_color_argb)
 215     native_display_delegate_->SetBackgroundColor(background_color_argb);
 216   const MultipleDisplayState new_state = ChooseDisplayState(power_state_);
 217   const bool success =
 218       EnterStateOrFallBackToSoftwareMirroring(new_state, power_state_);
 219
 220   // Force the DPMS on chrome startup as the driver doesn't always detect
 221   // that all displays are on when signing out.
 222   native_display_delegate_->ForceDPMSOn();
 223   native_display_delegate_->UngrabServer();
 224   NotifyObservers(success, new_state);
 225 }
 226
 227 bool DisplayConfigurator::IsMirroring() const {
 228   return display_state_ == MULTIPLE_DISPLAY_STATE_DUAL_MIRROR ||
 229       (mirroring_controller_ &&
 230        mirroring_controller_->SoftwareMirroringEnabled());
 231 }
 232
 233 bool DisplayConfigurator::ApplyProtections(const ContentProtections& requests) {
 234   for (DisplayStateList::const_iterator it = cached_displays_.begin();
 235        it != cached_displays_.end();
 236        ++it) {
 237     uint32_t all_desired = 0;
 238
 239     // In mirror mode, protection request of all displays need to be fulfilled.
 240     // In non-mirror mode, only request of client's display needs to be
 241     // fulfilled.
 242     ContentProtections::const_iterator request_it;
 243     if (IsMirroring()) {
 244       for (request_it = requests.begin();
 245            request_it != requests.end();
 246            ++request_it)
 247         all_desired |= request_it->second;
 248     } else {
 249       request_it = requests.find(it->display->display_id());
 250       if (request_it != requests.end())
 251         all_desired = request_it->second;
 252     }
 253
 254     switch (it->display->type()) {
 255       case DISPLAY_CONNECTION_TYPE_UNKNOWN:
 256         return false;
 257       // DisplayPort, DVI, and HDMI all support HDCP.
 258       case DISPLAY_CONNECTION_TYPE_DISPLAYPORT:
 259       case DISPLAY_CONNECTION_TYPE_DVI:
 260       case DISPLAY_CONNECTION_TYPE_HDMI: {
 261         HDCPState new_desired_state =
 262             (all_desired & CONTENT_PROTECTION_METHOD_HDCP) ?
 263                 HDCP_STATE_DESIRED : HDCP_STATE_UNDESIRED;
 264         if (!native_display_delegate_->SetHDCPState(*it->display,
 265                                                     new_desired_state))
 266           return false;
 267         break;
 268       }
 269       case DISPLAY_CONNECTION_TYPE_INTERNAL:
 270       case DISPLAY_CONNECTION_TYPE_VGA:
 271       case DISPLAY_CONNECTION_TYPE_NETWORK:
 272         // No protections for these types. Do nothing.
 273         break;
 274       case DISPLAY_CONNECTION_TYPE_NONE:
 275         NOTREACHED();
 276         break;
 277     }
 278   }
 279
 280   return true;
 281 }
 282
 283 DisplayConfigurator::ContentProtectionClientId
 284 DisplayConfigurator::RegisterContentProtectionClient() {
 285   if (!configure_display_)
 286     return kInvalidClientId;
 287
 288   return next_display_protection_client_id_++;
 289 }
 290
 291 void DisplayConfigurator::UnregisterContentProtectionClient(
 292     ContentProtectionClientId client_id) {
 293   client_protection_requests_.erase(client_id);
 294
 295   ContentProtections protections;
 296   for (ProtectionRequests::const_iterator it =
 297            client_protection_requests_.begin();
 298        it != client_protection_requests_.end();
 299        ++it) {
 300     for (ContentProtections::const_iterator it2 = it->second.begin();
 301          it2 != it->second.end();
 302          ++it2) {
 303       protections[it2->first] |= it2->second;
 304     }
 305   }
 306
 307   ApplyProtections(protections);
 308 }
 309
 310 bool DisplayConfigurator::QueryContentProtectionStatus(
 311     ContentProtectionClientId client_id,
 312     int64_t display_id,
 313     uint32_t* link_mask,
 314     uint32_t* protection_mask) {
 315   if (!configure_display_)
 316     return false;
 317
 318   uint32_t enabled = 0;
 319   uint32_t unfulfilled = 0;
 320   *link_mask = 0;
 321   for (DisplayStateList::const_iterator it = cached_displays_.begin();
 322        it != cached_displays_.end();
 323        ++it) {
 324     // Query display if it is in mirror mode or client on the same display.
 325     if (!IsMirroring() && it->display->display_id() != display_id)
 326       continue;
 327
 328     *link_mask |= it->display->type();
 329     switch (it->display->type()) {
 330       case DISPLAY_CONNECTION_TYPE_UNKNOWN:
 331         return false;
 332       // DisplayPort, DVI, and HDMI all support HDCP.
 333       case DISPLAY_CONNECTION_TYPE_DISPLAYPORT:
 334       case DISPLAY_CONNECTION_TYPE_DVI:
 335       case DISPLAY_CONNECTION_TYPE_HDMI: {
 336         HDCPState state;
 337         if (!native_display_delegate_->GetHDCPState(*it->display, &state))
 338           return false;
 339         if (state == HDCP_STATE_ENABLED)
 340           enabled |= CONTENT_PROTECTION_METHOD_HDCP;
 341         else
 342           unfulfilled |= CONTENT_PROTECTION_METHOD_HDCP;
 343         break;
 344       }
 345       case DISPLAY_CONNECTION_TYPE_INTERNAL:
 346       case DISPLAY_CONNECTION_TYPE_VGA:
 347       case DISPLAY_CONNECTION_TYPE_NETWORK:
 348         // No protections for these types. Do nothing.
 349         break;
 350       case DISPLAY_CONNECTION_TYPE_NONE:
 351         NOTREACHED();
 352         break;
 353     }
 354   }
 355
 356   // Don't reveal protections requested by other clients.
 357   ProtectionRequests::iterator it = client_protection_requests_.find(client_id);
 358   if (it != client_protection_requests_.end()) {
 359     uint32_t requested_mask = 0;
 360     if (it->second.find(display_id) != it->second.end())
 361       requested_mask = it->second[display_id];
 362     *protection_mask = enabled & ~unfulfilled & requested_mask;
 363   } else {
 364     *protection_mask = 0;
 365   }
 366   return true;
 367 }
 368
 369 bool DisplayConfigurator::EnableContentProtection(
 370     ContentProtectionClientId client_id,
 371     int64_t display_id,
 372     uint32_t desired_method_mask) {
 373   if (!configure_display_)
 374     return false;
 375
 376   ContentProtections protections;
 377   for (ProtectionRequests::const_iterator it =
 378            client_protection_requests_.begin();
 379        it != client_protection_requests_.end();
 380        ++it) {
 381     for (ContentProtections::const_iterator it2 = it->second.begin();
 382          it2 != it->second.end();
 383          ++it2) {
 384       if (it->first == client_id && it2->first == display_id)
 385         continue;
 386       protections[it2->first] |= it2->second;
 387     }
 388   }
 389   protections[display_id] |= desired_method_mask;
 390
 391   if (!ApplyProtections(protections))
 392     return false;
 393
 394   if (desired_method_mask == CONTENT_PROTECTION_METHOD_NONE) {
 395     if (client_protection_requests_.find(client_id) !=
 396         client_protection_requests_.end()) {
 397       client_protection_requests_[client_id].erase(display_id);
 398       if (client_protection_requests_[client_id].size() == 0)
 399         client_protection_requests_.erase(client_id);
 400     }
 401   } else {
 402     client_protection_requests_[client_id][display_id] = desired_method_mask;
 403   }
 404
 405   return true;
 406 }
 407
 408 std::vector<ui::ColorCalibrationProfile>
 409 DisplayConfigurator::GetAvailableColorCalibrationProfiles(int64_t display_id) {
 410   if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
 411           switches::kDisableDisplayColorCalibration)) {
 412     for (size_t i = 0; i < cached_displays_.size(); ++i) {
 413       if (cached_displays_[i].display &&
 414           cached_displays_[i].display->display_id() == display_id) {
 415         return native_display_delegate_->GetAvailableColorCalibrationProfiles(
 416             *cached_displays_[i].display);
 417       }
 418     }
 419   }
 420
 421   return std::vector<ui::ColorCalibrationProfile>();
 422 }
 423
 424 bool DisplayConfigurator::SetColorCalibrationProfile(
 425     int64_t display_id,
 426     ui::ColorCalibrationProfile new_profile) {
 427   for (size_t i = 0; i < cached_displays_.size(); ++i) {
 428     if (cached_displays_[i].display &&
 429         cached_displays_[i].display->display_id() == display_id) {
 430       return native_display_delegate_->SetColorCalibrationProfile(
 431           *cached_displays_[i].display, new_profile);
 432     }
 433   }
 434
 435   return false;
 436 }
 437
 438 void DisplayConfigurator::PrepareForExit() {
 439   configure_display_ = false;
 440 }
 441
 442 bool DisplayConfigurator::SetDisplayPower(
 443     chromeos::DisplayPowerState power_state,
 444     int flags) {
 445   if (!configure_display_)
 446     return false;
 447
 448   VLOG(1) << "SetDisplayPower: power_state="
 449           << DisplayPowerStateToString(power_state) << " flags=" << flags
 450           << ", configure timer="
 451           << (configure_timer_.IsRunning() ? "Running" : "Stopped");
 452   if (power_state == power_state_ && !(flags & kSetDisplayPowerForceProbe))
 453     return true;
 454
 455   native_display_delegate_->GrabServer();
 456   UpdateCachedDisplays();
 457
 458   const MultipleDisplayState new_state = ChooseDisplayState(power_state);
 459   bool attempted_change = false;
 460   bool success = false;
 461
 462   bool only_if_single_internal_display =
 463       flags & kSetDisplayPowerOnlyIfSingleInternalDisplay;
 464   bool single_internal_display =
 465       cached_displays_.size() == 1 &&
 466       cached_displays_[0].display->type() == DISPLAY_CONNECTION_TYPE_INTERNAL;
 467   if (single_internal_display || !only_if_single_internal_display) {
 468     success = EnterStateOrFallBackToSoftwareMirroring(new_state, power_state);
 469     attempted_change = true;
 470
 471     // Force the DPMS on since the driver doesn't always detect that it
 472     // should turn on. This is needed when coming back from idle suspend.
 473     if (success && power_state != chromeos::DISPLAY_POWER_ALL_OFF)
 474       native_display_delegate_->ForceDPMSOn();
 475   }
 476
 477   native_display_delegate_->UngrabServer();
 478   if (attempted_change)
 479     NotifyObservers(success, new_state);
 480   return true;
 481 }
 482
 483 bool DisplayConfigurator::SetDisplayMode(MultipleDisplayState new_state) {
 484   if (!configure_display_)
 485     return false;
 486
 487   VLOG(1) << "SetDisplayMode: state=" << DisplayStateToString(new_state);
 488   if (display_state_ == new_state) {
 489     // Cancel software mirroring if the state is moving from
 490     // MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED to
 491     // MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED.
 492     if (mirroring_controller_ &&
 493         new_state == MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED)
 494       mirroring_controller_->SetSoftwareMirroring(false);
 495     NotifyObservers(true, new_state);
 496     return true;
 497   }
 498
 499   native_display_delegate_->GrabServer();
 500   UpdateCachedDisplays();
 501   const bool success =
 502       EnterStateOrFallBackToSoftwareMirroring(new_state, power_state_);
 503   native_display_delegate_->UngrabServer();
 504
 505   NotifyObservers(success, new_state);
 506   return success;
 507 }
 508
 509 void DisplayConfigurator::OnConfigurationChanged() {
 510   // Configure displays with |kConfigureDelayMs| delay,
 511   // so that time-consuming ConfigureDisplays() won't be called multiple times.
 512   if (configure_timer_.IsRunning()) {
 513     // Note: when the timer is running it is possible that a different task
 514     // (SetDisplayPower()) is scheduled. In these cases, prefer the already
 515     // scheduled task to ConfigureDisplays() since ConfigureDisplays() performs
 516     // only basic configuration while SetDisplayPower() will perform additional
 517     // operations.
 518     configure_timer_.Reset();
 519   } else {
 520     configure_timer_.Start(
 521         FROM_HERE,
 522         base::TimeDelta::FromMilliseconds(kConfigureDelayMs),
 523         this,
 524         &DisplayConfigurator::ConfigureDisplays);
 525   }
 526 }
 527
 528 void DisplayConfigurator::AddObserver(Observer* observer) {
 529   observers_.AddObserver(observer);
 530 }
 531
 532 void DisplayConfigurator::RemoveObserver(Observer* observer) {
 533   observers_.RemoveObserver(observer);
 534 }
 535
 536 void DisplayConfigurator::SuspendDisplays() {
 537   // If the display is off due to user inactivity and there's only a single
 538   // internal display connected, switch to the all-on state before
 539   // suspending.  This shouldn't be very noticeable to the user since the
 540   // backlight is off at this point, and doing this lets us resume directly
 541   // into the "on" state, which greatly reduces resume times.
 542   if (power_state_ == chromeos::DISPLAY_POWER_ALL_OFF) {
 543     SetDisplayPower(chromeos::DISPLAY_POWER_ALL_ON,
 544                     kSetDisplayPowerOnlyIfSingleInternalDisplay);
 545
 546     // We need to make sure that the monitor configuration we just did actually
 547     // completes before we return, because otherwise the X message could be
 548     // racing with the HandleSuspendReadiness message.
 549     native_display_delegate_->SyncWithServer();
 550   }
 551 }
 552
 553 void DisplayConfigurator::ResumeDisplays() {
 554   // Force probing to ensure that we pick up any changes that were made
 555   // while the system was suspended.
 556   configure_timer_.Start(
 557       FROM_HERE,
 558       base::TimeDelta::FromMilliseconds(kResumeDelayMs),
 559       base::Bind(base::IgnoreResult(&DisplayConfigurator::SetDisplayPower),
 560                  base::Unretained(this),
 561                  power_state_,
 562                  kSetDisplayPowerForceProbe));
 563 }
 564
 565 void DisplayConfigurator::UpdateCachedDisplays() {
 566   std::vector<DisplaySnapshot*> snapshots =
 567       native_display_delegate_->GetDisplays();
 568
 569   cached_displays_.clear();
 570   for (size_t i = 0; i < snapshots.size(); ++i) {
 571     DisplayState display_state;
 572     display_state.display = snapshots[i];
 573     cached_displays_.push_back(display_state);
 574   }
 575
 576   touchscreen_delegate_->AssociateTouchscreens(&cached_displays_);
 577
 578   // Set |selected_mode| fields.
 579   for (size_t i = 0; i < cached_displays_.size(); ++i) {
 580     DisplayState* display_state = &cached_displays_[i];
 581     if (display_state->display->has_proper_display_id()) {
 582       gfx::Size size;
 583       if (state_controller_ &&
 584           state_controller_->GetResolutionForDisplayId(
 585               display_state->display->display_id(), &size)) {
 586         display_state->selected_mode =
 587             FindDisplayModeMatchingSize(*display_state->display, size);
 588       }
 589     }
 590     // Fall back to native mode.
 591     if (!display_state->selected_mode)
 592       display_state->selected_mode = display_state->display->native_mode();
 593   }
 594
 595   // Set |mirror_mode| fields.
 596   if (cached_displays_.size() == 2) {
 597     bool one_is_internal =
 598         cached_displays_[0].display->type() == DISPLAY_CONNECTION_TYPE_INTERNAL;
 599     bool two_is_internal =
 600         cached_displays_[1].display->type() == DISPLAY_CONNECTION_TYPE_INTERNAL;
 601     int internal_displays =
 602         (one_is_internal ? 1 : 0) + (two_is_internal ? 1 : 0);
 603     DCHECK_LT(internal_displays, 2);
 604     LOG_IF(WARNING, internal_displays == 2)
 605         << "Two internal displays detected.";
 606
 607     bool can_mirror = false;
 608     for (int attempt = 0; !can_mirror && attempt < 2; ++attempt) {
 609       // Try preserving external display's aspect ratio on the first attempt.
 610       // If that fails, fall back to the highest matching resolution.
 611       bool preserve_aspect = attempt == 0;
 612
 613       if (internal_displays == 1) {
 614         if (one_is_internal) {
 615           can_mirror = FindMirrorMode(&cached_displays_[0],
 616                                       &cached_displays_[1],
 617                                       is_panel_fitting_enabled_,
 618                                       preserve_aspect);
 619         } else {
 620           DCHECK(two_is_internal);
 621           can_mirror = FindMirrorMode(&cached_displays_[1],
 622                                       &cached_displays_[0],
 623                                       is_panel_fitting_enabled_,
 624                                       preserve_aspect);
 625         }
 626       } else {  // if (internal_displays == 0)
 627         // No panel fitting for external displays, so fall back to exact match.
 628         can_mirror = FindMirrorMode(
 629             &cached_displays_[0], &cached_displays_[1], false, preserve_aspect);
 630         if (!can_mirror && preserve_aspect) {
 631           // FindMirrorMode() will try to preserve aspect ratio of what it
 632           // thinks is external display, so if it didn't succeed with one, maybe
 633           // it will succeed with the other.  This way we will have the correct
 634           // aspect ratio on at least one of them.
 635           can_mirror = FindMirrorMode(&cached_displays_[1],
 636                                       &cached_displays_[0],
 637                                       false,
 638                                       preserve_aspect);
 639         }
 640       }
 641     }
 642   }
 643 }
 644
 645 bool DisplayConfigurator::FindMirrorMode(DisplayState* internal_display,
 646                                          DisplayState* external_display,
 647                                          bool try_panel_fitting,
 648                                          bool preserve_aspect) {
 649   const DisplayMode* internal_native_info =
 650       internal_display->display->native_mode();
 651   const DisplayMode* external_native_info =
 652       external_display->display->native_mode();
 653   if (!internal_native_info || !external_native_info)
 654     return false;
 655
 656   // Check if some external display resolution can be mirrored on internal.
 657   // Prefer the modes in the order they're present in DisplaySnapshot, assuming
 658   // this is the order in which they look better on the monitor.
 659   for (DisplayModeList::const_iterator external_it =
 660            external_display->display->modes().begin();
 661        external_it != external_display->display->modes().end();
 662        ++external_it) {
 663     const DisplayMode& external_info = **external_it;
 664     bool is_native_aspect_ratio =
 665         external_native_info->size().width() * external_info.size().height() ==
 666         external_native_info->size().height() * external_info.size().width();
 667     if (preserve_aspect && !is_native_aspect_ratio)
 668       continue;  // Allow only aspect ratio preserving modes for mirroring.
 669
 670     // Try finding an exact match.
 671     for (DisplayModeList::const_iterator internal_it =
 672              internal_display->display->modes().begin();
 673          internal_it != internal_display->display->modes().end();
 674          ++internal_it) {
 675       const DisplayMode& internal_info = **internal_it;
 676       if (internal_info.size().width() == external_info.size().width() &&
 677           internal_info.size().height() == external_info.size().height() &&
 678           internal_info.is_interlaced() == external_info.is_interlaced()) {
 679         internal_display->mirror_mode = *internal_it;
 680         external_display->mirror_mode = *external_it;
 681         return true;  // Mirror mode found.
 682       }
 683     }
 684
 685     // Try to create a matching internal display mode by panel fitting.
 686     if (try_panel_fitting) {
 687       // We can downscale by 1.125, and upscale indefinitely. Downscaling looks
 688       // ugly, so, can fit == can upscale. Also, internal panels don't support
 689       // fitting interlaced modes.
 690       bool can_fit = internal_native_info->size().width() >=
 691                          external_info.size().width() &&
 692                      internal_native_info->size().height() >=
 693                          external_info.size().height() &&
 694                      !external_info.is_interlaced();
 695       if (can_fit) {
 696         native_display_delegate_->AddMode(*internal_display->display,
 697                                           *external_it);
 698         internal_display->display->add_mode(*external_it);
 699         internal_display->mirror_mode = *external_it;
 700         external_display->mirror_mode = *external_it;
 701         return true;  // Mirror mode created.
 702       }
 703     }
 704   }
 705
 706   return false;
 707 }
 708
 709 void DisplayConfigurator::ConfigureDisplays() {
 710   if (!configure_display_)
 711     return;
 712
 713   native_display_delegate_->GrabServer();
 714   UpdateCachedDisplays();
 715   const MultipleDisplayState new_state = ChooseDisplayState(power_state_);
 716   const bool success =
 717       EnterStateOrFallBackToSoftwareMirroring(new_state, power_state_);
 718   native_display_delegate_->UngrabServer();
 719
 720   NotifyObservers(success, new_state);
 721 }
 722
 723 void DisplayConfigurator::NotifyObservers(
 724     bool success,
 725     MultipleDisplayState attempted_state) {
 726   if (success) {
 727     FOR_EACH_OBSERVER(
 728         Observer, observers_, OnDisplayModeChanged(cached_displays_));
 729   } else {
 730     FOR_EACH_OBSERVER(
 731         Observer, observers_, OnDisplayModeChangeFailed(attempted_state));
 732   }
 733 }
 734
 735 bool DisplayConfigurator::EnterStateOrFallBackToSoftwareMirroring(
 736     MultipleDisplayState display_state,
 737     chromeos::DisplayPowerState power_state) {
 738   bool success = EnterState(display_state, power_state);
 739   if (mirroring_controller_) {
 740     bool enable_software_mirroring = false;
 741     if (!success && display_state == MULTIPLE_DISPLAY_STATE_DUAL_MIRROR) {
 742       if (display_state_ != MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED ||
 743           power_state_ != power_state)
 744         EnterState(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED, power_state);
 745       enable_software_mirroring = success =
 746           display_state_ == MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED;
 747     }
 748     mirroring_controller_->SetSoftwareMirroring(enable_software_mirroring);
 749   }
 750   return success;
 751 }
 752
 753 bool DisplayConfigurator::EnterState(MultipleDisplayState display_state,
 754                                      chromeos::DisplayPowerState power_state) {
 755   std::vector<bool> display_power;
 756   int num_on_displays =
 757       GetDisplayPower(cached_displays_, power_state, &display_power);
 758   VLOG(1) << "EnterState: display=" << DisplayStateToString(display_state)
 759           << " power=" << DisplayPowerStateToString(power_state);
 760
 761   // Framebuffer dimensions.
 762   gfx::Size size;
 763
 764   std::vector<gfx::Point> new_origins(cached_displays_.size(), gfx::Point());
 765   std::vector<const DisplayMode*> new_mode;
 766   for (size_t i = 0; i < cached_displays_.size(); ++i)
 767     new_mode.push_back(cached_displays_[i].display->current_mode());
 768
 769   switch (display_state) {
 770     case MULTIPLE_DISPLAY_STATE_INVALID:
 771       NOTREACHED() << "Ignoring request to enter invalid state with "
 772                    << cached_displays_.size() << " connected display(s)";
 773       return false;
 774     case MULTIPLE_DISPLAY_STATE_HEADLESS:
 775       if (cached_displays_.size() != 0) {
 776         LOG(WARNING) << "Ignoring request to enter headless mode with "
 777                      << cached_displays_.size() << " connected display(s)";
 778         return false;
 779       }
 780       break;
 781     case MULTIPLE_DISPLAY_STATE_SINGLE: {
 782       // If there are multiple displays connected, only one should be turned on.
 783       if (cached_displays_.size() != 1 && num_on_displays != 1) {
 784         LOG(WARNING) << "Ignoring request to enter single mode with "
 785                      << cached_displays_.size() << " connected displays and "
 786                      << num_on_displays << " turned on";
 787         return false;
 788       }
 789
 790       for (size_t i = 0; i < cached_displays_.size(); ++i) {
 791         DisplayState* state = &cached_displays_[i];
 792         new_mode[i] = display_power[i] ? state->selected_mode : NULL;
 793
 794         if (display_power[i] || cached_displays_.size() == 1) {
 795           const DisplayMode* mode_info = state->selected_mode;
 796           if (!mode_info) {
 797             LOG(WARNING) << "No selected mode when configuring display: "
 798                          << state->display->ToString();
 799             return false;
 800           }
 801           if (mode_info->size() == gfx::Size(1024, 768)) {
 802             VLOG(1) << "Potentially misdetecting display(1024x768):"
 803                     << " displays size=" << cached_displays_.size()
 804                     << ", num_on_displays=" << num_on_displays
 805                     << ", current size:" << size.width() << "x" << size.height()
 806                     << ", i=" << i << ", display=" << state->display->ToString()
 807                     << ", display_mode=" << mode_info->ToString();
 808           }
 809           size = mode_info->size();
 810         }
 811       }
 812       break;
 813     }
 814     case MULTIPLE_DISPLAY_STATE_DUAL_MIRROR: {
 815       if (cached_displays_.size() != 2 ||
 816           (num_on_displays != 0 && num_on_displays != 2)) {
 817         LOG(WARNING) << "Ignoring request to enter mirrored mode with "
 818                      << cached_displays_.size() << " connected display(s) and "
 819                      << num_on_displays << " turned on";
 820         return false;
 821       }
 822
 823       const DisplayMode* mode_info = cached_displays_[0].mirror_mode;
 824       if (!mode_info) {
 825         LOG(WARNING) << "No mirror mode when configuring display: "
 826                      << cached_displays_[0].display->ToString();
 827         return false;
 828       }
 829       size = mode_info->size();
 830
 831       for (size_t i = 0; i < cached_displays_.size(); ++i) {
 832         DisplayState* state = &cached_displays_[i];
 833         new_mode[i] = display_power[i] ? state->mirror_mode : NULL;
 834       }
 835       break;
 836     }
 837     case MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED: {
 838       if (cached_displays_.size() != 2 ||
 839           (num_on_displays != 0 && num_on_displays != 2)) {
 840         LOG(WARNING) << "Ignoring request to enter extended mode with "
 841                      << cached_displays_.size() << " connected display(s) and "
 842                      << num_on_displays << " turned on";
 843         return false;
 844       }
 845
 846       for (size_t i = 0; i < cached_displays_.size(); ++i) {
 847         DisplayState* state = &cached_displays_[i];
 848         new_origins[i].set_y(size.height() ? size.height() + kVerticalGap : 0);
 849         new_mode[i] = display_power[i] ? state->selected_mode : NULL;
 850
 851         // Retain the full screen size even if all displays are off so the
 852         // same desktop configuration can be restored when the displays are
 853         // turned back on.
 854         const DisplayMode* mode_info = cached_displays_[i].selected_mode;
 855         if (!mode_info) {
 856           LOG(WARNING) << "No selected mode when configuring display: "
 857                        << state->display->ToString();
 858           return false;
 859         }
 860
 861         size.set_width(std::max<int>(size.width(), mode_info->size().width()));
 862         size.set_height(size.height() + (size.height() ? kVerticalGap : 0) +
 863                         mode_info->size().height());
 864       }
 865       break;
 866     }
 867   }
 868
 869   // Finally, apply the desired changes.
 870   bool all_succeeded = true;
 871   if (!cached_displays_.empty()) {
 872     native_display_delegate_->CreateFrameBuffer(size);
 873     for (size_t i = 0; i < cached_displays_.size(); ++i) {
 874       const DisplayState& state = cached_displays_[i];
 875       bool configure_succeeded = false;
 876
 877       while (true) {
 878         if (native_display_delegate_->Configure(
 879                 *state.display, new_mode[i], new_origins[i])) {
 880           state.display->set_current_mode(new_mode[i]);
 881           state.display->set_origin(new_origins[i]);
 882
 883           configure_succeeded = true;
 884           break;
 885         }
 886
 887         const DisplayMode* mode_info = new_mode[i];
 888         if (!mode_info)
 889           break;
 890
 891         // Find the mode with the next-best resolution and see if that can
 892         // be set.
 893         int best_mode_pixels = 0;
 894
 895         int current_mode_pixels = mode_info->size().GetArea();
 896         for (DisplayModeList::const_iterator it =
 897                  state.display->modes().begin();
 898              it != state.display->modes().end();
 899              it++) {
 900           int pixel_count = (*it)->size().GetArea();
 901           if ((pixel_count < current_mode_pixels) &&
 902               (pixel_count > best_mode_pixels)) {
 903             new_mode[i] = *it;
 904             best_mode_pixels = pixel_count;
 905           }
 906         }
 907
 908         if (best_mode_pixels == 0)
 909           break;
 910       }
 911
 912       if (!configure_succeeded)
 913         all_succeeded = false;
 914
 915       // If we are trying to set mirror mode and one of the modesets fails,
 916       // then the two monitors will be mis-matched.  In this case, return
 917       // false to let the observers be aware.
 918       if (display_state == MULTIPLE_DISPLAY_STATE_DUAL_MIRROR &&
 919           display_power[i] &&
 920           state.display->current_mode() != state.mirror_mode)
 921         all_succeeded = false;
 922     }
 923   }
 924
 925   if (all_succeeded) {
 926     display_state_ = display_state;
 927     power_state_ = power_state;
 928     framebuffer_size_ = size;
 929   }
 930   return all_succeeded;
 931 }
 932
 933 MultipleDisplayState DisplayConfigurator::ChooseDisplayState(
 934     chromeos::DisplayPowerState power_state) const {
 935   int num_on_displays = GetDisplayPower(cached_displays_, power_state, NULL);
 936   switch (cached_displays_.size()) {
 937     case 0:
 938       return MULTIPLE_DISPLAY_STATE_HEADLESS;
 939     case 1:
 940       return MULTIPLE_DISPLAY_STATE_SINGLE;
 941     case 2: {
 942       if (num_on_displays == 1) {
 943         // If only one display is currently turned on, return the "single"
 944         // state so that its native mode will be used.
 945         return MULTIPLE_DISPLAY_STATE_SINGLE;
 946       } else {
 947         if (!state_controller_)
 948           return MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED;
 949         // With either both displays on or both displays off, use one of the
 950         // dual modes.
 951         std::vector<int64_t> display_ids;
 952         for (size_t i = 0; i < cached_displays_.size(); ++i) {
 953           // If display id isn't available, switch to extended mode.
 954           if (!cached_displays_[i].display->has_proper_display_id())
 955             return MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED;
 956           display_ids.push_back(cached_displays_[i].display->display_id());
 957         }
 958         return state_controller_->GetStateForDisplayIds(display_ids);
 959       }
 960     }
 961     default:
 962       NOTREACHED();
 963   }
 964   return MULTIPLE_DISPLAY_STATE_INVALID;
 965 }
 966
 967 }  // namespace ui