SF: Move toggleKernelIdleTimer to DMC

Remove a special case for the default display by tracking the enabled
state per display.

Bug: 241285876
Bug: 355424160
Flag: EXEMPT refactor
Test: presubmit
Change-Id: Ife697e9f31bdf833910132fb0a71918b29c350eb
diff --git a/services/surfaceflinger/Display/DisplayModeController.cpp b/services/surfaceflinger/Display/DisplayModeController.cpp
index c43d585..0e9218c 100644
--- a/services/surfaceflinger/Display/DisplayModeController.cpp
+++ b/services/surfaceflinger/Display/DisplayModeController.cpp
@@ -22,7 +22,9 @@
 #include "Display/DisplaySnapshot.h"
 #include "DisplayHardware/HWComposer.h"
 
+#include <android-base/properties.h>
 #include <common/FlagManager.h>
+#include <common/trace.h>
 #include <ftl/concat.h>
 #include <ftl/expected.h>
 #include <log/log.h>
@@ -237,4 +239,63 @@
     }
 }
 
+void DisplayModeController::updateKernelIdleTimer(PhysicalDisplayId displayId) {
+    std::lock_guard lock(mDisplayLock);
+    const auto& displayPtr = FTL_TRY(mDisplays.get(displayId).ok_or(ftl::Unit())).get();
+
+    const auto controllerOpt = displayPtr->selectorPtr->kernelIdleTimerController();
+    if (!controllerOpt) return;
+
+    using KernelIdleTimerAction = scheduler::RefreshRateSelector::KernelIdleTimerAction;
+
+    switch (displayPtr->selectorPtr->getIdleTimerAction()) {
+        case KernelIdleTimerAction::TurnOff:
+            if (displayPtr->isKernelIdleTimerEnabled) {
+                SFTRACE_INT("KernelIdleTimer", 0);
+                updateKernelIdleTimer(displayId, std::chrono::milliseconds::zero(), *controllerOpt);
+                displayPtr->isKernelIdleTimerEnabled = false;
+            }
+            break;
+        case KernelIdleTimerAction::TurnOn:
+            if (!displayPtr->isKernelIdleTimerEnabled) {
+                SFTRACE_INT("KernelIdleTimer", 1);
+                const auto timeout = displayPtr->selectorPtr->getIdleTimerTimeout();
+                updateKernelIdleTimer(displayId, timeout, *controllerOpt);
+                displayPtr->isKernelIdleTimerEnabled = true;
+            }
+            break;
+    }
+}
+
+void DisplayModeController::updateKernelIdleTimer(PhysicalDisplayId displayId,
+                                                  std::chrono::milliseconds timeout,
+                                                  KernelIdleTimerController controller) {
+    switch (controller) {
+        case KernelIdleTimerController::HwcApi:
+            mComposerPtr->setIdleTimerEnabled(displayId, timeout);
+            break;
+
+        case KernelIdleTimerController::Sysprop:
+            using namespace std::string_literals;
+            base::SetProperty("graphics.display.kernel_idle_timer.enabled"s,
+                              timeout > std::chrono::milliseconds::zero() ? "true"s : "false"s);
+            break;
+    }
+}
+
+auto DisplayModeController::getKernelIdleTimerState(PhysicalDisplayId displayId) const
+        -> KernelIdleTimerState {
+    std::lock_guard lock(mDisplayLock);
+    const auto& displayPtr =
+            FTL_EXPECT(mDisplays.get(displayId).ok_or(KernelIdleTimerState())).get();
+
+    const auto desiredModeIdOpt =
+            (std::scoped_lock(displayPtr->desiredModeLock), displayPtr->desiredModeOpt)
+                    .transform([](const display::DisplayModeRequest& request) {
+                        return request.mode.modePtr->getId();
+                    });
+
+    return {desiredModeIdOpt, displayPtr->isKernelIdleTimerEnabled};
+}
+
 } // namespace android::display
diff --git a/services/surfaceflinger/Display/DisplayModeController.h b/services/surfaceflinger/Display/DisplayModeController.h
index 258b04b..9ec603d 100644
--- a/services/surfaceflinger/Display/DisplayModeController.h
+++ b/services/surfaceflinger/Display/DisplayModeController.h
@@ -97,6 +97,17 @@
     void setActiveMode(PhysicalDisplayId, DisplayModeId, Fps vsyncRate, Fps renderFps)
             EXCLUDES(mDisplayLock);
 
+    void updateKernelIdleTimer(PhysicalDisplayId) REQUIRES(kMainThreadContext)
+            EXCLUDES(mDisplayLock);
+
+    struct KernelIdleTimerState {
+        std::optional<DisplayModeId> desiredModeIdOpt = std::nullopt;
+        bool isEnabled = false;
+    };
+
+    KernelIdleTimerState getKernelIdleTimerState(PhysicalDisplayId) const
+            REQUIRES(kMainThreadContext) EXCLUDES(mDisplayLock);
+
 private:
     struct Display {
         template <size_t N>
@@ -121,6 +132,8 @@
 
         DisplayModeRequestOpt pendingModeOpt GUARDED_BY(kMainThreadContext);
         bool isModeSetPending GUARDED_BY(kMainThreadContext) = false;
+
+        bool isKernelIdleTimerEnabled GUARDED_BY(kMainThreadContext) = false;
     };
 
     using DisplayPtr = std::unique_ptr<Display>;
@@ -128,6 +141,10 @@
     void setActiveModeLocked(PhysicalDisplayId, DisplayModeId, Fps vsyncRate, Fps renderFps)
             REQUIRES(mDisplayLock);
 
+    using KernelIdleTimerController = scheduler::RefreshRateSelector::KernelIdleTimerController;
+    void updateKernelIdleTimer(PhysicalDisplayId, std::chrono::milliseconds timeout,
+                               KernelIdleTimerController) REQUIRES(mDisplayLock);
+
     // Set once when initializing the DisplayModeController, which the HWComposer must outlive.
     HWComposer* mComposerPtr = nullptr;