1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "../Macros.h"
18 
19 #include <android/sysprop/InputProperties.sysprop.h>
20 #include "MultiTouchInputMapper.h"
21 
22 namespace android {
23 
24 // --- Constants ---
25 
26 // Maximum number of slots supported when using the slot-based Multitouch Protocol B.
27 static constexpr size_t MAX_SLOTS = 32;
28 
29 // --- MultiTouchInputMapper ---
30 
MultiTouchInputMapper(InputDeviceContext & deviceContext,const InputReaderConfiguration & readerConfig)31 MultiTouchInputMapper::MultiTouchInputMapper(InputDeviceContext& deviceContext,
32                                              const InputReaderConfiguration& readerConfig)
33       : TouchInputMapper(deviceContext, readerConfig) {}
34 
~MultiTouchInputMapper()35 MultiTouchInputMapper::~MultiTouchInputMapper() {}
36 
reset(nsecs_t when)37 std::list<NotifyArgs> MultiTouchInputMapper::reset(nsecs_t when) {
38     mPointerIdBits.clear();
39     mMultiTouchMotionAccumulator.reset(mDeviceContext);
40     return TouchInputMapper::reset(when);
41 }
42 
process(const RawEvent & rawEvent)43 std::list<NotifyArgs> MultiTouchInputMapper::process(const RawEvent& rawEvent) {
44     std::list<NotifyArgs> out = TouchInputMapper::process(rawEvent);
45 
46     mMultiTouchMotionAccumulator.process(rawEvent);
47     return out;
48 }
49 
getActiveBitId(const MultiTouchMotionAccumulator::Slot & inSlot)50 std::optional<int32_t> MultiTouchInputMapper::getActiveBitId(
51         const MultiTouchMotionAccumulator::Slot& inSlot) {
52     if (mHavePointerIds) {
53         int32_t trackingId = inSlot.getTrackingId();
54         for (BitSet32 idBits(mPointerIdBits); !idBits.isEmpty();) {
55             int32_t n = idBits.clearFirstMarkedBit();
56             if (mPointerTrackingIdMap[n] == trackingId) {
57                 return std::make_optional(n);
58             }
59         }
60     }
61     return std::nullopt;
62 }
63 
syncTouch(nsecs_t when,RawState * outState)64 void MultiTouchInputMapper::syncTouch(nsecs_t when, RawState* outState) {
65     size_t inCount = mMultiTouchMotionAccumulator.getSlotCount();
66     size_t outCount = 0;
67     BitSet32 newPointerIdBits;
68     mHavePointerIds = true;
69 
70     for (size_t inIndex = 0; inIndex < inCount; inIndex++) {
71         const MultiTouchMotionAccumulator::Slot& inSlot =
72                 mMultiTouchMotionAccumulator.getSlot(inIndex);
73         if (!inSlot.isInUse()) {
74             continue;
75         }
76 
77         if (inSlot.getToolType() == ToolType::PALM) {
78             std::optional<int32_t> id = getActiveBitId(inSlot);
79             if (id) {
80                 outState->rawPointerData.canceledIdBits.markBit(id.value());
81             }
82             if (DEBUG_POINTERS) {
83                 ALOGI("Stop processing slot %zu for it received a palm event from device %s",
84                       inIndex, getDeviceName().c_str());
85             }
86             continue;
87         }
88 
89         if (outCount >= MAX_POINTERS) {
90             if (DEBUG_POINTERS) {
91                 ALOGD("MultiTouch device %s emitted more than maximum of %zu pointers; "
92                       "ignoring the rest.",
93                       getDeviceName().c_str(), MAX_POINTERS);
94             }
95             break; // too many fingers!
96         }
97 
98         RawPointerData::Pointer& outPointer = outState->rawPointerData.pointers[outCount];
99         outPointer.x = inSlot.getX();
100         outPointer.y = inSlot.getY();
101         outPointer.pressure = inSlot.getPressure();
102         outPointer.touchMajor = inSlot.getTouchMajor();
103         outPointer.touchMinor = inSlot.getTouchMinor();
104         outPointer.toolMajor = inSlot.getToolMajor();
105         outPointer.toolMinor = inSlot.getToolMinor();
106         outPointer.orientation = inSlot.getOrientation();
107         outPointer.distance = inSlot.getDistance();
108         outPointer.tiltX = 0;
109         outPointer.tiltY = 0;
110 
111         outPointer.toolType = inSlot.getToolType();
112         if (outPointer.toolType == ToolType::UNKNOWN) {
113             outPointer.toolType = mTouchButtonAccumulator.getToolType();
114             if (outPointer.toolType == ToolType::UNKNOWN) {
115                 outPointer.toolType = ToolType::FINGER;
116             }
117         } else if (outPointer.toolType == ToolType::STYLUS && !mStylusMtToolSeen) {
118             mStylusMtToolSeen = true;
119             // The multi-touch device produced a stylus event with MT_TOOL_PEN. Dynamically
120             // re-configure this input device so that we add SOURCE_STYLUS if we haven't already.
121             // This is to cover the case where we cannot reliably detect whether a multi-touch
122             // device will ever produce stylus events when it is initially being configured.
123             if (!isFromSource(mSource, AINPUT_SOURCE_STYLUS)) {
124                 // Add the stylus source immediately so that it is included in any events generated
125                 // before we have a chance to re-configure the device.
126                 mSource |= AINPUT_SOURCE_STYLUS;
127                 bumpGeneration();
128             }
129         }
130         if (mShouldSimulateStylusWithTouch && outPointer.toolType == ToolType::FINGER) {
131             outPointer.toolType = ToolType::STYLUS;
132         }
133 
134         bool isHovering = mTouchButtonAccumulator.getToolType() != ToolType::MOUSE &&
135                 (mTouchButtonAccumulator.isHovering() ||
136                  (mRawPointerAxes.pressure.valid && inSlot.getPressure() <= 0));
137         outPointer.isHovering = isHovering;
138 
139         // Assign pointer id using tracking id if available.
140         if (mHavePointerIds) {
141             const int32_t trackingId = inSlot.getTrackingId();
142             int32_t id = -1;
143             if (trackingId >= 0) {
144                 for (BitSet32 idBits(mPointerIdBits); !idBits.isEmpty();) {
145                     uint32_t n = idBits.clearFirstMarkedBit();
146                     if (mPointerTrackingIdMap[n] == trackingId) {
147                         id = n;
148                         break;
149                     }
150                 }
151 
152                 if (id < 0 && !mPointerIdBits.isFull()) {
153                     id = mPointerIdBits.markFirstUnmarkedBit();
154                     mPointerTrackingIdMap[id] = trackingId;
155                 }
156             }
157             if (id < 0) {
158                 mHavePointerIds = false;
159                 outState->rawPointerData.clearIdBits();
160                 newPointerIdBits.clear();
161             } else {
162                 outPointer.id = id;
163                 outState->rawPointerData.idToIndex[id] = outCount;
164                 outState->rawPointerData.markIdBit(id, isHovering);
165                 newPointerIdBits.markBit(id);
166             }
167         }
168         outCount += 1;
169     }
170 
171     outState->rawPointerData.pointerCount = outCount;
172     mPointerIdBits = newPointerIdBits;
173 
174     mMultiTouchMotionAccumulator.finishSync();
175 }
176 
reconfigure(nsecs_t when,const InputReaderConfiguration & config,ConfigurationChanges changes)177 std::list<NotifyArgs> MultiTouchInputMapper::reconfigure(nsecs_t when,
178                                                          const InputReaderConfiguration& config,
179                                                          ConfigurationChanges changes) {
180     const bool simulateStylusWithTouch =
181             sysprop::InputProperties::simulate_stylus_with_touch().value_or(false);
182     if (simulateStylusWithTouch != mShouldSimulateStylusWithTouch) {
183         mShouldSimulateStylusWithTouch = simulateStylusWithTouch;
184         bumpGeneration();
185     }
186     return TouchInputMapper::reconfigure(when, config, changes);
187 }
188 
configureRawPointerAxes()189 void MultiTouchInputMapper::configureRawPointerAxes() {
190     TouchInputMapper::configureRawPointerAxes();
191 
192     getAbsoluteAxisInfo(ABS_MT_POSITION_X, &mRawPointerAxes.x);
193     getAbsoluteAxisInfo(ABS_MT_POSITION_Y, &mRawPointerAxes.y);
194     getAbsoluteAxisInfo(ABS_MT_TOUCH_MAJOR, &mRawPointerAxes.touchMajor);
195     getAbsoluteAxisInfo(ABS_MT_TOUCH_MINOR, &mRawPointerAxes.touchMinor);
196     getAbsoluteAxisInfo(ABS_MT_WIDTH_MAJOR, &mRawPointerAxes.toolMajor);
197     getAbsoluteAxisInfo(ABS_MT_WIDTH_MINOR, &mRawPointerAxes.toolMinor);
198     getAbsoluteAxisInfo(ABS_MT_ORIENTATION, &mRawPointerAxes.orientation);
199     getAbsoluteAxisInfo(ABS_MT_PRESSURE, &mRawPointerAxes.pressure);
200     getAbsoluteAxisInfo(ABS_MT_DISTANCE, &mRawPointerAxes.distance);
201     getAbsoluteAxisInfo(ABS_MT_TRACKING_ID, &mRawPointerAxes.trackingId);
202     getAbsoluteAxisInfo(ABS_MT_SLOT, &mRawPointerAxes.slot);
203 
204     if (mRawPointerAxes.trackingId.valid && mRawPointerAxes.slot.valid &&
205         mRawPointerAxes.slot.minValue == 0 && mRawPointerAxes.slot.maxValue > 0) {
206         size_t slotCount = mRawPointerAxes.slot.maxValue + 1;
207         if (slotCount > MAX_SLOTS) {
208             ALOGW("MultiTouch Device %s reported %zu slots but the framework "
209                   "only supports a maximum of %zu slots at this time.",
210                   getDeviceName().c_str(), slotCount, MAX_SLOTS);
211             slotCount = MAX_SLOTS;
212         }
213         mMultiTouchMotionAccumulator.configure(getDeviceContext(), slotCount,
214                                                /*usingSlotsProtocol=*/true);
215     } else {
216         mMultiTouchMotionAccumulator.configure(getDeviceContext(), MAX_POINTERS,
217                                                /*usingSlotsProtocol=*/false);
218     }
219 }
220 
hasStylus() const221 bool MultiTouchInputMapper::hasStylus() const {
222     return mStylusMtToolSeen || mTouchButtonAccumulator.hasStylus() ||
223             mShouldSimulateStylusWithTouch;
224 }
225 
226 } // namespace android
227