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 // The evdev multi-touch protocol does not allow userspace applications to query the initial or
39 // current state of the pointers at any time. This means if we clear our accumulated state when
40 // resetting the input mapper, there's no way to rebuild the full initial state of the pointers.
41 // We can only wait for updates to all the pointers and axes. Rather than clearing the state and
42 // rebuilding the state from scratch, we work around this kernel API limitation by never
43 // fully clearing any state specific to the multi-touch protocol.
44 return TouchInputMapper::reset(when);
45 }
46
process(const RawEvent * rawEvent)47 std::list<NotifyArgs> MultiTouchInputMapper::process(const RawEvent* rawEvent) {
48 std::list<NotifyArgs> out = TouchInputMapper::process(rawEvent);
49
50 mMultiTouchMotionAccumulator.process(rawEvent);
51 return out;
52 }
53
getActiveBitId(const MultiTouchMotionAccumulator::Slot & inSlot)54 std::optional<int32_t> MultiTouchInputMapper::getActiveBitId(
55 const MultiTouchMotionAccumulator::Slot& inSlot) {
56 if (mHavePointerIds) {
57 int32_t trackingId = inSlot.getTrackingId();
58 for (BitSet32 idBits(mPointerIdBits); !idBits.isEmpty();) {
59 int32_t n = idBits.clearFirstMarkedBit();
60 if (mPointerTrackingIdMap[n] == trackingId) {
61 return std::make_optional(n);
62 }
63 }
64 }
65 return std::nullopt;
66 }
67
syncTouch(nsecs_t when,RawState * outState)68 void MultiTouchInputMapper::syncTouch(nsecs_t when, RawState* outState) {
69 size_t inCount = mMultiTouchMotionAccumulator.getSlotCount();
70 size_t outCount = 0;
71 BitSet32 newPointerIdBits;
72 mHavePointerIds = true;
73
74 for (size_t inIndex = 0; inIndex < inCount; inIndex++) {
75 const MultiTouchMotionAccumulator::Slot& inSlot =
76 mMultiTouchMotionAccumulator.getSlot(inIndex);
77 if (!inSlot.isInUse()) {
78 continue;
79 }
80
81 if (inSlot.getToolType() == ToolType::PALM) {
82 std::optional<int32_t> id = getActiveBitId(inSlot);
83 if (id) {
84 outState->rawPointerData.canceledIdBits.markBit(id.value());
85 }
86 if (DEBUG_POINTERS) {
87 ALOGI("Stop processing slot %zu for it received a palm event from device %s",
88 inIndex, getDeviceName().c_str());
89 }
90 continue;
91 }
92
93 if (outCount >= MAX_POINTERS) {
94 if (DEBUG_POINTERS) {
95 ALOGD("MultiTouch device %s emitted more than maximum of %zu pointers; "
96 "ignoring the rest.",
97 getDeviceName().c_str(), MAX_POINTERS);
98 }
99 break; // too many fingers!
100 }
101
102 RawPointerData::Pointer& outPointer = outState->rawPointerData.pointers[outCount];
103 outPointer.x = inSlot.getX();
104 outPointer.y = inSlot.getY();
105 outPointer.pressure = inSlot.getPressure();
106 outPointer.touchMajor = inSlot.getTouchMajor();
107 outPointer.touchMinor = inSlot.getTouchMinor();
108 outPointer.toolMajor = inSlot.getToolMajor();
109 outPointer.toolMinor = inSlot.getToolMinor();
110 outPointer.orientation = inSlot.getOrientation();
111 outPointer.distance = inSlot.getDistance();
112 outPointer.tiltX = 0;
113 outPointer.tiltY = 0;
114
115 outPointer.toolType = inSlot.getToolType();
116 if (outPointer.toolType == ToolType::UNKNOWN) {
117 outPointer.toolType = mTouchButtonAccumulator.getToolType();
118 if (outPointer.toolType == ToolType::UNKNOWN) {
119 outPointer.toolType = ToolType::FINGER;
120 }
121 } else if (outPointer.toolType == ToolType::STYLUS && !mStylusMtToolSeen) {
122 mStylusMtToolSeen = true;
123 // The multi-touch device produced a stylus event with MT_TOOL_PEN. Dynamically
124 // re-configure this input device so that we add SOURCE_STYLUS if we haven't already.
125 // This is to cover the case where we cannot reliably detect whether a multi-touch
126 // device will ever produce stylus events when it is initially being configured.
127 if (!isFromSource(mSource, AINPUT_SOURCE_STYLUS)) {
128 // Add the stylus source immediately so that it is included in any events generated
129 // before we have a chance to re-configure the device.
130 mSource |= AINPUT_SOURCE_STYLUS;
131 bumpGeneration();
132 }
133 }
134 if (shouldSimulateStylusWithTouch() && outPointer.toolType == ToolType::FINGER) {
135 outPointer.toolType = ToolType::STYLUS;
136 }
137
138 bool isHovering = mTouchButtonAccumulator.getToolType() != ToolType::MOUSE &&
139 (mTouchButtonAccumulator.isHovering() ||
140 (mRawPointerAxes.pressure.valid && inSlot.getPressure() <= 0));
141 outPointer.isHovering = isHovering;
142
143 // Assign pointer id using tracking id if available.
144 if (mHavePointerIds) {
145 int32_t trackingId = inSlot.getTrackingId();
146 int32_t id = -1;
147 if (trackingId >= 0) {
148 for (BitSet32 idBits(mPointerIdBits); !idBits.isEmpty();) {
149 uint32_t n = idBits.clearFirstMarkedBit();
150 if (mPointerTrackingIdMap[n] == trackingId) {
151 id = n;
152 }
153 }
154
155 if (id < 0 && !mPointerIdBits.isFull()) {
156 id = mPointerIdBits.markFirstUnmarkedBit();
157 mPointerTrackingIdMap[id] = trackingId;
158 }
159 }
160 if (id < 0) {
161 mHavePointerIds = false;
162 outState->rawPointerData.clearIdBits();
163 newPointerIdBits.clear();
164 } else {
165 outPointer.id = id;
166 outState->rawPointerData.idToIndex[id] = outCount;
167 outState->rawPointerData.markIdBit(id, isHovering);
168 newPointerIdBits.markBit(id);
169 }
170 }
171 outCount += 1;
172 }
173
174 outState->rawPointerData.pointerCount = outCount;
175 mPointerIdBits = newPointerIdBits;
176
177 mMultiTouchMotionAccumulator.finishSync();
178 }
179
configureRawPointerAxes()180 void MultiTouchInputMapper::configureRawPointerAxes() {
181 TouchInputMapper::configureRawPointerAxes();
182
183 getAbsoluteAxisInfo(ABS_MT_POSITION_X, &mRawPointerAxes.x);
184 getAbsoluteAxisInfo(ABS_MT_POSITION_Y, &mRawPointerAxes.y);
185 getAbsoluteAxisInfo(ABS_MT_TOUCH_MAJOR, &mRawPointerAxes.touchMajor);
186 getAbsoluteAxisInfo(ABS_MT_TOUCH_MINOR, &mRawPointerAxes.touchMinor);
187 getAbsoluteAxisInfo(ABS_MT_WIDTH_MAJOR, &mRawPointerAxes.toolMajor);
188 getAbsoluteAxisInfo(ABS_MT_WIDTH_MINOR, &mRawPointerAxes.toolMinor);
189 getAbsoluteAxisInfo(ABS_MT_ORIENTATION, &mRawPointerAxes.orientation);
190 getAbsoluteAxisInfo(ABS_MT_PRESSURE, &mRawPointerAxes.pressure);
191 getAbsoluteAxisInfo(ABS_MT_DISTANCE, &mRawPointerAxes.distance);
192 getAbsoluteAxisInfo(ABS_MT_TRACKING_ID, &mRawPointerAxes.trackingId);
193 getAbsoluteAxisInfo(ABS_MT_SLOT, &mRawPointerAxes.slot);
194
195 if (mRawPointerAxes.trackingId.valid && mRawPointerAxes.slot.valid &&
196 mRawPointerAxes.slot.minValue == 0 && mRawPointerAxes.slot.maxValue > 0) {
197 size_t slotCount = mRawPointerAxes.slot.maxValue + 1;
198 if (slotCount > MAX_SLOTS) {
199 ALOGW("MultiTouch Device %s reported %zu slots but the framework "
200 "only supports a maximum of %zu slots at this time.",
201 getDeviceName().c_str(), slotCount, MAX_SLOTS);
202 slotCount = MAX_SLOTS;
203 }
204 mMultiTouchMotionAccumulator.configure(getDeviceContext(), slotCount,
205 /*usingSlotsProtocol=*/true);
206 } else {
207 mMultiTouchMotionAccumulator.configure(getDeviceContext(), MAX_POINTERS,
208 /*usingSlotsProtocol=*/false);
209 }
210 }
211
hasStylus() const212 bool MultiTouchInputMapper::hasStylus() const {
213 return mStylusMtToolSeen || mTouchButtonAccumulator.hasStylus() ||
214 shouldSimulateStylusWithTouch();
215 }
216
shouldSimulateStylusWithTouch() const217 bool MultiTouchInputMapper::shouldSimulateStylusWithTouch() const {
218 static const bool SIMULATE_STYLUS_WITH_TOUCH =
219 sysprop::InputProperties::simulate_stylus_with_touch().value_or(false);
220 return SIMULATE_STYLUS_WITH_TOUCH &&
221 mParameters.deviceType == Parameters::DeviceType::TOUCH_SCREEN;
222 }
223
224 } // namespace android
225