Dynamically add STYLUS source for multi-touch devices - part 2

This is a follow-up to I70cc15f8f354e3fc876024d194a6f320fabd6d2c.

The previous change added SOURCE_STYLUS to events dynamically if they
came from a stylus tool type. In this change, we instead dynamically add
SOURCE_STYLUS to the InputDevice whenever it produces an MT_TOOL_PEN
event. This means all the events generated by that device will have
SOURCE_STYLUS added to it from that point onwards.

Bug: 246991366
Test: atest inputflinger_tests
Change-Id: I61963563eb4cdd41957247db100fcb87cc1b278b
diff --git a/services/inputflinger/reader/mapper/MultiTouchInputMapper.cpp b/services/inputflinger/reader/mapper/MultiTouchInputMapper.cpp
index ccff353..b193dff 100644
--- a/services/inputflinger/reader/mapper/MultiTouchInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/MultiTouchInputMapper.cpp
@@ -119,6 +119,18 @@
             if (outPointer.toolType == AMOTION_EVENT_TOOL_TYPE_UNKNOWN) {
                 outPointer.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;
             }
+        } else if (outPointer.toolType == AMOTION_EVENT_TOOL_TYPE_STYLUS && !mStylusMtToolSeen) {
+            mStylusMtToolSeen = true;
+            // The multi-touch device produced a stylus event with MT_TOOL_PEN. Dynamically
+            // re-configure this input device so that we add SOURCE_STYLUS if we haven't already.
+            // This is to cover the case where we cannot reliably detect whether a multi-touch
+            // device will ever produce stylus events when it is initially being configured.
+            if (!isFromSource(mSource, AINPUT_SOURCE_STYLUS)) {
+                // Add the stylus source immediately so that it is included in any events generated
+                // before we have a chance to re-configure the device.
+                mSource |= AINPUT_SOURCE_STYLUS;
+                bumpGeneration();
+            }
         }
         if (shouldSimulateStylusWithTouch() &&
             outPointer.toolType == AMOTION_EVENT_TOOL_TYPE_FINGER) {
@@ -200,7 +212,8 @@
 }
 
 bool MultiTouchInputMapper::hasStylus() const {
-    return mTouchButtonAccumulator.hasStylus() || shouldSimulateStylusWithTouch();
+    return mStylusMtToolSeen || mTouchButtonAccumulator.hasStylus() ||
+            shouldSimulateStylusWithTouch();
 }
 
 bool MultiTouchInputMapper::shouldSimulateStylusWithTouch() const {
diff --git a/services/inputflinger/reader/mapper/MultiTouchInputMapper.h b/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
index ddf9e80..5f8bccf 100644
--- a/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
+++ b/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
@@ -50,6 +50,8 @@
     // Specifies the pointer id bits that are in use, and their associated tracking id.
     BitSet32 mPointerIdBits;
     int32_t mPointerTrackingIdMap[MAX_POINTER_ID + 1];
+
+    bool mStylusMtToolSeen{false};
 };
 
 } // namespace android
diff --git a/services/inputflinger/reader/mapper/TouchInputMapper.cpp b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
index bc55fe5..5be694f 100644
--- a/services/inputflinger/reader/mapper/TouchInputMapper.cpp
+++ b/services/inputflinger/reader/mapper/TouchInputMapper.cpp
@@ -3763,15 +3763,12 @@
     PointerCoords pointerCoords[MAX_POINTERS];
     PointerProperties pointerProperties[MAX_POINTERS];
     uint32_t pointerCount = 0;
-    bool stylusToolFound = false;
     while (!idBits.isEmpty()) {
         uint32_t id = idBits.clearFirstMarkedBit();
         uint32_t index = idToIndex[id];
         pointerProperties[pointerCount].copyFrom(properties[index]);
         pointerCoords[pointerCount].copyFrom(coords[index]);
 
-        stylusToolFound |= isStylusToolType(pointerProperties[pointerCount].toolType);
-
         if (changedId >= 0 && id == uint32_t(changedId)) {
             action |= pointerCount << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
         }
@@ -3803,12 +3800,6 @@
     if (mDeviceMode == DeviceMode::POINTER) {
         mPointerController->getPosition(&xCursorPosition, &yCursorPosition);
     }
-    if (stylusToolFound) {
-        // Dynamically add the stylus source when there's a stylus tool being used to cover the case
-        // where we cannot reliably detect whether a multi-touch device will ever produce stylus
-        // events when it is initially being configured.
-        source |= AINPUT_SOURCE_STYLUS;
-    }
     const int32_t displayId = getAssociatedDisplayId().value_or(ADISPLAY_ID_NONE);
     const int32_t deviceId = getDeviceId();
     std::vector<TouchVideoFrame> frames = getDeviceContext().getVideoFrames();
diff --git a/services/inputflinger/tests/InputReader_test.cpp b/services/inputflinger/tests/InputReader_test.cpp
index 5c5fc77..6b6d0bb 100644
--- a/services/inputflinger/tests/InputReader_test.cpp
+++ b/services/inputflinger/tests/InputReader_test.cpp
@@ -10788,11 +10788,12 @@
     ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyMotionWasNotCalled());
 }
 
-TEST_F(MultiTouchInputMapperTest, ToolTypeSource) {
+TEST_F(MultiTouchInputMapperTest, StylusSourceIsAddedDynamicallyFromToolType) {
     addConfigurationProperty("touch.deviceType", "touchScreen");
     prepareDisplay(DISPLAY_ORIENTATION_0);
     prepareAxes(POSITION | ID | SLOT | PRESSURE | TOOL_TYPE);
     MultiTouchInputMapper& mapper = addMapperAndConfigure<MultiTouchInputMapper>();
+    ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyDeviceResetWasCalled());
 
     // Even if the device supports reporting the ABS_MT_TOOL_TYPE axis, which could give it the
     // ability to report MT_TOOL_PEN, we do not report the device as coming from a stylus source.
@@ -10801,7 +10802,7 @@
     ASSERT_EQ(AINPUT_SOURCE_TOUCHSCREEN, mapper.getSources());
 
     // However, if the device ever ends up reporting an event with MT_TOOL_PEN, it should be
-    // reported with the stylus source, even through the device doesn't support the stylus source.
+    // reported with the stylus source.
     processId(mapper, FIRST_TRACKING_ID);
     processToolType(mapper, MT_TOOL_PEN);
     processPosition(mapper, 100, 200);
@@ -10812,15 +10813,27 @@
                   WithSource(AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_STYLUS),
                   WithToolType(AMOTION_EVENT_TOOL_TYPE_STYLUS))));
 
+    // Now that we know the device supports styluses, ensure that the device is re-configured with
+    // the stylus source.
+    ASSERT_EQ(AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_STYLUS, mapper.getSources());
+    {
+        const auto& devices = mReader->getInputDevices();
+        auto deviceInfo =
+                std::find_if(devices.begin(), devices.end(),
+                             [](const InputDeviceInfo& info) { return info.getId() == DEVICE_ID; });
+        LOG_ALWAYS_FATAL_IF(deviceInfo == devices.end(), "Cannot find InputDevice");
+        ASSERT_EQ(AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_STYLUS, deviceInfo->getSources());
+    }
+
+    // Ensure the device was not reset to prevent interruptions of any ongoing gestures.
+    ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyDeviceResetWasNotCalled());
+
     processId(mapper, INVALID_TRACKING_ID);
     processSync(mapper);
     ASSERT_NO_FATAL_FAILURE(mFakeListener->assertNotifyMotionWasCalled(
             AllOf(WithMotionAction(AMOTION_EVENT_ACTION_UP),
                   WithSource(AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_STYLUS),
                   WithToolType(AMOTION_EVENT_TOOL_TYPE_STYLUS))));
-
-    // The mapper should still report only a touchscreen source.
-    ASSERT_EQ(AINPUT_SOURCE_TOUCHSCREEN, mapper.getSources());
 }
 
 // --- MultiTouchInputMapperTest_ExternalDevice ---