Add new `TouchpadInputMapper` class

This will replace `MultiTouchInputMapper` and `SingleTouchInputMapper`
for touchpad devices, and will be the wrapper for the gestures library.

Bug: 251196347
Test: connect Apple Magic Trackpad 2 to device, check logs come out
Test: atest inputflinger_tests
Change-Id: Ia8ee1779a40c6c6f98373e114c040bf13b7f213d

6 files changed, 85 insertions, 2 deletions

diff --git a/services/inputflinger/reader/Android.bp b/services/inputflinger/reader/Android.bp
index 46e86de84c..551ad7a398 100644
--- a/services/inputflinger/reader/Android.bp
+++ b/services/inputflinger/reader/Android.bp
@@ -51,6 +51,7 @@ filegroup {
         "mapper/SingleTouchInputMapper.cpp",
         "mapper/SwitchInputMapper.cpp",
         "mapper/TouchInputMapper.cpp",
+        "mapper/TouchpadInputMapper.cpp",
         "mapper/VibratorInputMapper.cpp",
         "mapper/accumulator/CursorButtonAccumulator.cpp",
         "mapper/accumulator/CursorScrollAccumulator.cpp",
diff --git a/services/inputflinger/reader/EventHub.cpp b/services/inputflinger/reader/EventHub.cpp
index 0aaef53c0d..f2ea90c291 100644
--- a/services/inputflinger/reader/EventHub.cpp
+++ b/services/inputflinger/reader/EventHub.cpp
@@ -2215,6 +2215,10 @@ void EventHub::openDeviceLocked(const std::string& devicePath) {
         // a touch screen.
         if (device->keyBitmask.test(BTN_TOUCH) || !haveGamepadButtons) {
             device->classes |= (InputDeviceClass::TOUCH | InputDeviceClass::TOUCH_MT);
+            if (device->propBitmask.test(INPUT_PROP_POINTER) &&
+                !device->keyBitmask.any(BTN_TOOL_PEN, BTN_TOOL_FINGER) && !haveStylusButtons) {
+                device->classes |= InputDeviceClass::TOUCHPAD;
+            }
         }
         // Is this an old style single-touch driver?
     } else if (device->keyBitmask.test(BTN_TOUCH) && device->absBitmask.test(ABS_X) &&
diff --git a/services/inputflinger/reader/InputDevice.cpp b/services/inputflinger/reader/InputDevice.cpp
index e6ab8722f6..6ca629835d 100644
--- a/services/inputflinger/reader/InputDevice.cpp
+++ b/services/inputflinger/reader/InputDevice.cpp
@@ -33,6 +33,7 @@
 #include "SensorInputMapper.h"
 #include "SingleTouchInputMapper.h"
 #include "SwitchInputMapper.h"
+#include "TouchpadInputMapper.h"
 #include "VibratorInputMapper.h"
 
 using android::hardware::input::InputDeviceCountryCode;
@@ -208,7 +209,11 @@ void InputDevice::addEventHubDevice(int32_t eventHubId, bool populateMappers) {
     }
 
     // Touchscreens and touchpad devices.
-    if (classes.test(InputDeviceClass::TOUCH_MT)) {
+    // TODO(b/251196347): replace this with a proper flag.
+    constexpr bool ENABLE_NEW_TOUCHPAD_STACK = false;
+    if (ENABLE_NEW_TOUCHPAD_STACK && classes.test(InputDeviceClass::TOUCHPAD)) {
+        mappers.push_back(std::make_unique<TouchpadInputMapper>(*contextPtr));
+    } else if (classes.test(InputDeviceClass::TOUCH_MT)) {
         mappers.push_back(std::make_unique<MultiTouchInputMapper>(*contextPtr));
     } else if (classes.test(InputDeviceClass::TOUCH)) {
         mappers.push_back(std::make_unique<SingleTouchInputMapper>(*contextPtr));
diff --git a/services/inputflinger/reader/include/EventHub.h b/services/inputflinger/reader/include/EventHub.h
index 8e5f15f338..42ca482a68 100644
--- a/services/inputflinger/reader/include/EventHub.h
+++ b/services/inputflinger/reader/include/EventHub.h
@@ -94,7 +94,7 @@ enum class InputDeviceClass : uint32_t {
     /* The input device is a cursor device such as a trackball or mouse. */
     CURSOR = 0x00000008,
 
-    /* The input device is a multi-touch touchscreen. */
+    /* The input device is a multi-touch touchscreen or touchpad. */
     TOUCH_MT = 0x00000010,
 
     /* The input device is a directional pad (implies keyboard, has DPAD keys). */
@@ -130,6 +130,9 @@ enum class InputDeviceClass : uint32_t {
     /* The input device has sysfs controllable lights */
     LIGHT = 0x00008000,
 
+    /* The input device is a touchpad, requiring an on-screen cursor. */
+    TOUCHPAD = 0x00010000,
+
     /* The input device is virtual (not a real device, not part of UI configuration). */
     VIRTUAL = 0x40000000,
 
diff --git a/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp b/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp
new file mode 100644
index 0000000000..3ad1de4cd4
--- /dev/null
+++ b/services/inputflinger/reader/mapper/TouchpadInputMapper.cpp
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "../Macros.h"
+
+#include "TouchpadInputMapper.h"
+
+namespace android {
+
+TouchpadInputMapper::TouchpadInputMapper(InputDeviceContext& deviceContext)
+      : InputMapper(deviceContext) {}
+
+uint32_t TouchpadInputMapper::getSources() const {
+    return AINPUT_SOURCE_MOUSE | AINPUT_SOURCE_TOUCHPAD;
+}
+
+std::list<NotifyArgs> TouchpadInputMapper::process(const RawEvent* rawEvent) {
+    ALOGD("TODO: process event type=0x%x code=0x%x value=0x%x", rawEvent->type, rawEvent->code,
+          rawEvent->value);
+    return {};
+}
+
+} // namespace android
diff --git a/services/inputflinger/reader/mapper/TouchpadInputMapper.h b/services/inputflinger/reader/mapper/TouchpadInputMapper.h
new file mode 100644
index 0000000000..81a76d27be
--- /dev/null
+++ b/services/inputflinger/reader/mapper/TouchpadInputMapper.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "EventHub.h"
+#include "InputDevice.h"
+#include "InputMapper.h"
+#include "NotifyArgs.h"
+
+namespace android {
+
+class TouchpadInputMapper : public InputMapper {
+public:
+    explicit TouchpadInputMapper(InputDeviceContext& deviceContext);
+
+    virtual uint32_t getSources() const override;
+    [[nodiscard]] virtual std::list<NotifyArgs> process(const RawEvent* rawEvent) override;
+};
+
+} // namespace android