Add primary min range check to turn on the kernel idle timer.

BUG: 191435579
Test: atest RefreshRateConfigsTest
Test: atest SurfaceFlinger_test
Test: atest libsurfaceflinger_unittest

Change-Id: Ibd885a2bed8c889ccc622fb4e7a852a9568309d6
diff --git a/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp b/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
index 0eb16e2..bca5092 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
+++ b/services/surfaceflinger/Scheduler/RefreshRateConfigs.cpp
@@ -859,6 +859,7 @@
     const auto& deviceMin = *mMinSupportedRefreshRate;
     const auto& minByPolicy = getMinRefreshRateByPolicyLocked();
     const auto& maxByPolicy = getMaxRefreshRateByPolicyLocked();
+    const auto& currentPolicy = getCurrentPolicyLocked();
 
     // Kernel idle timer will set the refresh rate to the device min. If DisplayManager says that
     // the min allowed refresh rate is higher than the device min, we do not want to enable the
@@ -867,6 +868,10 @@
         return RefreshRateConfigs::KernelIdleTimerAction::TurnOff;
     }
     if (minByPolicy == maxByPolicy) {
+        // when min primary range in display manager policy is below device min turn on the timer.
+        if (currentPolicy->primaryRange.min.lessThanWithMargin(deviceMin.getFps())) {
+            return RefreshRateConfigs::KernelIdleTimerAction::TurnOn;
+        }
         return RefreshRateConfigs::KernelIdleTimerAction::TurnOff;
     }
     // Turn on the timer in all other cases.