InputReader: Bump generation when associated display changes

When the display association changes, we need to bump the device
generation because the associated display is part of the java
InputDevice, so we need to notify listeners about changes in the
associated display.

Bug: 324299318
Test: atest VirtualDpadTest --iterations
Change-Id: Id5da99804b3e170d03fb1ca4c126b782a7587c7c

2 files changed, 9 insertions, 0 deletions

diff --git a/services/inputflinger/reader/InputDevice.cpp b/services/inputflinger/reader/InputDevice.cpp
index f3f15df151..2baf576903 100644
--- a/services/inputflinger/reader/InputDevice.cpp
+++ b/services/inputflinger/reader/InputDevice.cpp
@@ -265,6 +265,8 @@ std::list<NotifyArgs> InputDevice::configureInternal(nsecs_t when,
         }
 
         if (!changes.any() || changes.test(Change::DISPLAY_INFO)) {
+            const auto oldAssociatedDisplayId = getAssociatedDisplayId();
+
             // In most situations, no port or name will be specified.
             mAssociatedDisplayPort = std::nullopt;
             mAssociatedDisplayUniqueId = std::nullopt;
@@ -306,6 +308,10 @@ std::list<NotifyArgs> InputDevice::configureInternal(nsecs_t when,
                           getName().c_str(), mAssociatedDisplayUniqueId->c_str());
                 }
             }
+
+            if (getAssociatedDisplayId() != oldAssociatedDisplayId) {
+                bumpGeneration();
+            }
         }
 
         for_each_mapper([this, when, &readerConfig, changes, &out](InputMapper& mapper) {
diff --git a/services/inputflinger/tests/InputReader_test.cpp b/services/inputflinger/tests/InputReader_test.cpp
index c1dc7ffcfb..476f755bae 100644
--- a/services/inputflinger/tests/InputReader_test.cpp
+++ b/services/inputflinger/tests/InputReader_test.cpp
@@ -2893,9 +2893,12 @@ TEST_F(InputDeviceTest, Configure_UniqueId_CorrectlyMatches) {
     mFakePolicy->addDisplayViewport(SECONDARY_DISPLAY_ID, DISPLAY_WIDTH, DISPLAY_HEIGHT,
                                     ui::ROTATION_0, /* isActive= */ true, DISPLAY_UNIQUE_ID,
                                     NO_PORT, ViewportType::INTERNAL);
+    const auto initialGeneration = mDevice->getGeneration();
     unused += mDevice->configure(ARBITRARY_TIME, mFakePolicy->getReaderConfiguration(),
                                  InputReaderConfiguration::Change::DISPLAY_INFO);
     ASSERT_EQ(DISPLAY_UNIQUE_ID, mDevice->getAssociatedDisplayUniqueId());
+    ASSERT_GT(mDevice->getGeneration(), initialGeneration);
+    ASSERT_EQ(mDevice->getDeviceInfo().getAssociatedDisplayId(), SECONDARY_DISPLAY_ID);
 }
 
 /**