Preserve multi-touch slot state when resetting input mappers
The existing pattern in InputReader is that when a mapper is reset, all
of its state is cleared and state of the buttons/axes is
queried through EventHub to rebuild the current state of the mapper.
This approach does not work for multi-touch devices, since there is no
way to query the current state of the contacts through the evdev
multi-touch protocol.
Since we cannot fully rebuild the current state of a multi-touch device,
we work around this limitation by never clearing the multi-touch state.
Bug: 248506674
Test: atest inputflinger_tests
Change-Id: Ic59d9fcb4e13fe262c422825c2485185004b719b
diff --git a/services/inputflinger/reader/mapper/MultiTouchInputMapper.h b/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
index 212c9c9..75cde8e 100644
--- a/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
+++ b/services/inputflinger/reader/mapper/MultiTouchInputMapper.h
@@ -68,7 +68,6 @@
MultiTouchMotionAccumulator();
void configure(InputDeviceContext& deviceContext, size_t slotCount, bool usingSlotsProtocol);
- void reset(InputDeviceContext& deviceContext);
void process(const RawEvent* rawEvent);
void finishSync();
bool hasStylus() const;
@@ -85,7 +84,7 @@
bool mUsingSlotsProtocol;
bool mHaveStylus;
- void clearSlots(int32_t initialSlot);
+ void resetSlots();
void warnIfNotInUse(const RawEvent& event, const Slot& slot);
};