Let InputReader set mouse cursor's display.

InputReader was already responsible to bind device/event and display. It
makes sense to further extend it to control the display where mouse
cursor is shown.

Bug: 146385350
Test: Mouse cursor shows up at expected display.
Test: atest inputflinger_tests
Change-Id: Ie7a9546550b70c8834462b06de929472196fe713
diff --git a/services/inputflinger/reader/mapper/CursorInputMapper.cpp b/services/inputflinger/reader/mapper/CursorInputMapper.cpp
index f69138e..69a75ba 100644
--- a/services/inputflinger/reader/mapper/CursorInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/CursorInputMapper.cpp
@@ -189,12 +189,32 @@
 
         // Update the PointerController if viewports changed.
         if (mParameters.mode == Parameters::MODE_POINTER) {
-            getPolicy()->obtainPointerController(getDeviceId());
+            updatePointerControllerDisplayViewport(*config);
         }
         bumpGeneration();
     }
 }
 
+void CursorInputMapper::updatePointerControllerDisplayViewport(
+        const InputReaderConfiguration& config) {
+    std::optional<DisplayViewport> viewport =
+            config.getDisplayViewportById(config.defaultPointerDisplayId);
+    if (!viewport) {
+        ALOGW("Can't find the designated viewport with ID %" PRId32 " to update cursor input "
+              "mapper. Fall back to default display",
+              config.defaultPointerDisplayId);
+        viewport = config.getDisplayViewportById(ADISPLAY_ID_DEFAULT);
+    }
+
+    if (!viewport) {
+        ALOGE("Still can't find a viable viewport to update cursor input mapper. Skip setting it to"
+              " PointerController.");
+        return;
+    }
+
+    mPointerController->setDisplayViewport(*viewport);
+}
+
 void CursorInputMapper::configureParameters() {
     mParameters.mode = Parameters::MODE_POINTER;
     String8 cursorModeString;
diff --git a/services/inputflinger/reader/mapper/CursorInputMapper.h b/services/inputflinger/reader/mapper/CursorInputMapper.h
index 77d122a..d56f9be 100644
--- a/services/inputflinger/reader/mapper/CursorInputMapper.h
+++ b/services/inputflinger/reader/mapper/CursorInputMapper.h
@@ -117,8 +117,9 @@
     void dumpParameters(std::string& dump);
 
     void sync(nsecs_t when);
+    void updatePointerControllerDisplayViewport(const InputReaderConfiguration& config);
 };
 
 } // namespace android
 
-#endif // _UI_INPUTREADER_CURSOR_INPUT_MAPPER_H
\ No newline at end of file
+#endif // _UI_INPUTREADER_CURSOR_INPUT_MAPPER_H
diff --git a/services/inputflinger/reader/mapper/TouchInputMapper.cpp b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
index c80a2dc..b66caca 100644
--- a/services/inputflinger/reader/mapper/TouchInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
@@ -552,9 +552,10 @@
  * Determine which DisplayViewport to use.
  * 1. If display port is specified, return the matching viewport. If matching viewport not
  * found, then return.
- * 2. If a device has associated display, get the matching viewport by either unique id or by
+ * 2. Always use the suggested viewport from WindowManagerService for pointers.
+ * 3. If a device has associated display, get the matching viewport by either unique id or by
  * the display type (internal or external).
- * 3. Otherwise, use a non-display viewport.
+ * 4. Otherwise, use a non-display viewport.
  */
 std::optional<DisplayViewport> TouchInputMapper::findViewport() {
     if (mParameters.hasAssociatedDisplay) {
@@ -564,6 +565,17 @@
             return mDevice->getAssociatedViewport();
         }
 
+        if (mDeviceMode == DEVICE_MODE_POINTER) {
+            std::optional<DisplayViewport> viewport =
+                    mConfig.getDisplayViewportById(mConfig.defaultPointerDisplayId);
+            if (viewport) {
+                return viewport;
+            } else {
+                ALOGW("Can't find designated display viewport with ID %" PRId32 " for pointers.",
+                      mConfig.defaultPointerDisplayId);
+            }
+        }
+
         // Check if uniqueDisplayId is specified in idc file.
         if (!mParameters.uniqueDisplayId.empty()) {
             return mConfig.getDisplayViewportByUniqueId(mParameters.uniqueDisplayId);
@@ -749,6 +761,7 @@
         (mDeviceMode == DEVICE_MODE_DIRECT && mConfig.showTouches)) {
         if (mPointerController == nullptr || viewportChanged) {
             mPointerController = getPolicy()->obtainPointerController(getDeviceId());
+            mPointerController->setDisplayViewport(mViewport);
         }
     } else {
         mPointerController.clear();