From 952c926acb5f24b9e2854a75668c329680200b35 Mon Sep 17 00:00:00 2001
From: Kriti Dang <kritidang@google.com>
Date: Wed, 20 Jul 2022 17:03:04 +0200
Subject: [PATCH] Clearing the DPI information, when forced Size is cleared

Bug: When forced size is cleared, but not DPI, it can result in wrong
DPI information.

Bug: 238951067
Test: adb shell dumpsys display (shows correct dpi values)
Change-Id: Ie8b0b2009ba141072a91262cacf7293d786238b1
---
 .../com/android/server/wm/DisplayContent.java   | 17 ++++++++++++++---
 .../android/server/wm/WindowManagerService.java |  4 +++-
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 409e0ed3ab610..e57a8722ab59b 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -269,6 +269,8 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
     /** For {@link #setForcedScalingMode} to apply flag {@link Display#FLAG_SCALING_DISABLED}. */
     static final int FORCE_SCALING_MODE_DISABLED = 1;
 
+    static final float INVALID_DPI = 0.0f;
+
     @IntDef(prefix = { "FORCE_SCALING_MODE_" }, value = {
             FORCE_SCALING_MODE_AUTO,
             FORCE_SCALING_MODE_DISABLED
@@ -2935,7 +2937,15 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
 
     /** If the given width and height equal to initial size, the setting will be cleared. */
     void setForcedSize(int width, int height) {
-        // Can't force size higher than the maximal allowed
+        setForcedSize(width, height, INVALID_DPI, INVALID_DPI);
+    }
+
+    /**
+     * If the given width and height equal to initial size, the setting will be cleared.
+     * If xPpi or yDpi is equal to {@link #INVALID_DPI}, the values are ignored.
+     */
+    void setForcedSize(int width, int height, float xDPI, float yDPI) {
+  	// Can't force size higher than the maximal allowed
         if (mMaxUiWidth > 0 && width > mMaxUiWidth) {
             final float ratio = mMaxUiWidth / (float) width;
             height = (int) (height * ratio);
@@ -2954,8 +2964,9 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
         }
 
         Slog.i(TAG_WM, "Using new display size: " + width + "x" + height);
-        updateBaseDisplayMetrics(width, height, mBaseDisplayDensity, mBaseDisplayPhysicalXDpi,
-                mBaseDisplayPhysicalYDpi);
+        updateBaseDisplayMetrics(width, height, mBaseDisplayDensity,
+                xDPI != INVALID_DPI ? xDPI : mBaseDisplayPhysicalXDpi,
+                yDPI != INVALID_DPI ? yDPI : mBaseDisplayPhysicalYDpi);
         reconfigureDisplayLocked();
 
         if (!mIsSizeForced) {
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 00e8d8bdaaec7..179358eb8d4a3 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -5780,7 +5780,9 @@ public class WindowManagerService extends IWindowManager.Stub
                 final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
                 if (displayContent != null) {
                     displayContent.setForcedSize(displayContent.mInitialDisplayWidth,
-                            displayContent.mInitialDisplayHeight);
+                            displayContent.mInitialDisplayHeight,
+                            displayContent.mInitialPhysicalXDpi,
+                            displayContent.mInitialPhysicalXDpi);
                 }
             }
         } finally {