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 "JoystickInputMapper.h"
20
21 namespace android {
22
JoystickInputMapper(InputDeviceContext & deviceContext,const InputReaderConfiguration & readerConfig)23 JoystickInputMapper::JoystickInputMapper(InputDeviceContext& deviceContext,
24 const InputReaderConfiguration& readerConfig)
25 : InputMapper(deviceContext, readerConfig) {}
26
~JoystickInputMapper()27 JoystickInputMapper::~JoystickInputMapper() {}
28
getSources() const29 uint32_t JoystickInputMapper::getSources() const {
30 return AINPUT_SOURCE_JOYSTICK;
31 }
32
populateDeviceInfo(InputDeviceInfo & info)33 void JoystickInputMapper::populateDeviceInfo(InputDeviceInfo& info) {
34 InputMapper::populateDeviceInfo(info);
35
36 for (const auto& [_, axis] : mAxes) {
37 addMotionRange(axis.axisInfo.axis, axis, info);
38
39 if (axis.axisInfo.mode == AxisInfo::MODE_SPLIT) {
40 addMotionRange(axis.axisInfo.highAxis, axis, info);
41 }
42 }
43 }
44
addMotionRange(int32_t axisId,const Axis & axis,InputDeviceInfo & info)45 void JoystickInputMapper::addMotionRange(int32_t axisId, const Axis& axis, InputDeviceInfo& info) {
46 info.addMotionRange(axisId, AINPUT_SOURCE_JOYSTICK, axis.min, axis.max, axis.flat, axis.fuzz,
47 axis.resolution);
48 /* In order to ease the transition for developers from using the old axes
49 * to the newer, more semantically correct axes, we'll continue to register
50 * the old axes as duplicates of their corresponding new ones. */
51 int32_t compatAxis = getCompatAxis(axisId);
52 if (compatAxis >= 0) {
53 info.addMotionRange(compatAxis, AINPUT_SOURCE_JOYSTICK, axis.min, axis.max, axis.flat,
54 axis.fuzz, axis.resolution);
55 }
56 }
57
58 /* A mapping from axes the joystick actually has to the axes that should be
59 * artificially created for compatibility purposes.
60 * Returns -1 if no compatibility axis is needed. */
getCompatAxis(int32_t axis)61 int32_t JoystickInputMapper::getCompatAxis(int32_t axis) {
62 switch (axis) {
63 case AMOTION_EVENT_AXIS_LTRIGGER:
64 return AMOTION_EVENT_AXIS_BRAKE;
65 case AMOTION_EVENT_AXIS_RTRIGGER:
66 return AMOTION_EVENT_AXIS_GAS;
67 }
68 return -1;
69 }
70
dump(std::string & dump)71 void JoystickInputMapper::dump(std::string& dump) {
72 dump += INDENT2 "Joystick Input Mapper:\n";
73
74 dump += INDENT3 "Axes:\n";
75 for (const auto& [rawAxis, axis] : mAxes) {
76 const char* label = InputEventLookup::getAxisLabel(axis.axisInfo.axis);
77 if (label) {
78 dump += StringPrintf(INDENT4 "%s", label);
79 } else {
80 dump += StringPrintf(INDENT4 "%d", axis.axisInfo.axis);
81 }
82 if (axis.axisInfo.mode == AxisInfo::MODE_SPLIT) {
83 label = InputEventLookup::getAxisLabel(axis.axisInfo.highAxis);
84 if (label) {
85 dump += StringPrintf(" / %s (split at %d)", label, axis.axisInfo.splitValue);
86 } else {
87 dump += StringPrintf(" / %d (split at %d)", axis.axisInfo.highAxis,
88 axis.axisInfo.splitValue);
89 }
90 } else if (axis.axisInfo.mode == AxisInfo::MODE_INVERT) {
91 dump += " (invert)";
92 }
93
94 dump += StringPrintf(": min=%0.5f, max=%0.5f, flat=%0.5f, fuzz=%0.5f, resolution=%0.5f\n",
95 axis.min, axis.max, axis.flat, axis.fuzz, axis.resolution);
96 dump += StringPrintf(INDENT4 " scale=%0.5f, offset=%0.5f, "
97 "highScale=%0.5f, highOffset=%0.5f\n",
98 axis.scale, axis.offset, axis.highScale, axis.highOffset);
99 dump += StringPrintf(INDENT4 " rawAxis=%d, rawMin=%d, rawMax=%d, "
100 "rawFlat=%d, rawFuzz=%d, rawResolution=%d\n",
101 rawAxis, axis.rawAxisInfo.minValue, axis.rawAxisInfo.maxValue,
102 axis.rawAxisInfo.flat, axis.rawAxisInfo.fuzz,
103 axis.rawAxisInfo.resolution);
104 }
105 }
106
reconfigure(nsecs_t when,const InputReaderConfiguration & config,ConfigurationChanges changes)107 std::list<NotifyArgs> JoystickInputMapper::reconfigure(nsecs_t when,
108 const InputReaderConfiguration& config,
109 ConfigurationChanges changes) {
110 std::list<NotifyArgs> out = InputMapper::reconfigure(when, config, changes);
111
112 if (!changes.any()) { // first time only
113 // Collect all axes.
114 for (int32_t abs = 0; abs <= ABS_MAX; abs++) {
115 if (!(getAbsAxisUsage(abs, getDeviceContext().getDeviceClasses())
116 .test(InputDeviceClass::JOYSTICK))) {
117 continue; // axis must be claimed by a different device
118 }
119
120 if (std::optional<RawAbsoluteAxisInfo> rawAxisInfo = getAbsoluteAxisInfo(abs);
121 rawAxisInfo) {
122 // Map axis.
123 AxisInfo axisInfo;
124 const bool explicitlyMapped = !getDeviceContext().mapAxis(abs, &axisInfo);
125
126 if (!explicitlyMapped) {
127 // Axis is not explicitly mapped, will choose a generic axis later.
128 axisInfo.mode = AxisInfo::MODE_NORMAL;
129 axisInfo.axis = -1;
130 }
131 mAxes.insert({abs, createAxis(axisInfo, rawAxisInfo.value(), explicitlyMapped)});
132 }
133 }
134
135 // If there are too many axes, start dropping them.
136 // Prefer to keep explicitly mapped axes.
137 if (mAxes.size() > PointerCoords::MAX_AXES) {
138 ALOGI("Joystick '%s' has %zu axes but the framework only supports a maximum of %d.",
139 getDeviceName().c_str(), mAxes.size(), PointerCoords::MAX_AXES);
140 pruneAxes(true);
141 pruneAxes(false);
142 }
143
144 // Assign generic axis ids to remaining axes.
145 int32_t nextGenericAxisId = AMOTION_EVENT_AXIS_GENERIC_1;
146 for (auto it = mAxes.begin(); it != mAxes.end(); /*increment it inside loop*/) {
147 Axis& axis = it->second;
148 if (axis.axisInfo.axis < 0) {
149 while (nextGenericAxisId <= AMOTION_EVENT_MAXIMUM_VALID_AXIS_VALUE &&
150 haveAxis(nextGenericAxisId)) {
151 nextGenericAxisId += 1;
152 }
153
154 if (nextGenericAxisId <= AMOTION_EVENT_MAXIMUM_VALID_AXIS_VALUE) {
155 axis.axisInfo.axis = nextGenericAxisId;
156 nextGenericAxisId += 1;
157 } else {
158 ALOGI("Ignoring joystick '%s' axis %d because all of the generic axis ids "
159 "have already been assigned to other axes.",
160 getDeviceName().c_str(), it->first);
161 it = mAxes.erase(it);
162 continue;
163 }
164 }
165 it++;
166 }
167 }
168 return out;
169 }
170
createAxis(const AxisInfo & axisInfo,const RawAbsoluteAxisInfo & rawAxisInfo,bool explicitlyMapped)171 JoystickInputMapper::Axis JoystickInputMapper::createAxis(const AxisInfo& axisInfo,
172 const RawAbsoluteAxisInfo& rawAxisInfo,
173 bool explicitlyMapped) {
174 // Apply flat override.
175 int32_t rawFlat = axisInfo.flatOverride < 0 ? rawAxisInfo.flat : axisInfo.flatOverride;
176
177 float scale = std::numeric_limits<float>::signaling_NaN();
178 float highScale = std::numeric_limits<float>::signaling_NaN();
179 float highOffset = 0;
180 float offset = 0;
181 float min = 0;
182 // Calculate scaling factors and limits.
183 if (axisInfo.mode == AxisInfo::MODE_SPLIT) {
184 scale = 1.0f / (axisInfo.splitValue - rawAxisInfo.minValue);
185 highScale = 1.0f / (rawAxisInfo.maxValue - axisInfo.splitValue);
186 } else if (isCenteredAxis(axisInfo.axis)) {
187 scale = 2.0f / (rawAxisInfo.maxValue - rawAxisInfo.minValue);
188 offset = avg(rawAxisInfo.minValue, rawAxisInfo.maxValue) * -scale;
189 highOffset = offset;
190 highScale = scale;
191 min = -1.0f;
192 } else {
193 scale = 1.0f / (rawAxisInfo.maxValue - rawAxisInfo.minValue);
194 highScale = scale;
195 }
196
197 constexpr float max = 1.0;
198 const float flat = rawFlat * scale;
199 const float fuzz = rawAxisInfo.fuzz * scale;
200 const float resolution = rawAxisInfo.resolution * scale;
201
202 // To eliminate noise while the joystick is at rest, filter out small variations
203 // in axis values up front.
204 const float filter = fuzz ? fuzz : flat * 0.25f;
205 return Axis(rawAxisInfo, axisInfo, explicitlyMapped, scale, offset, highScale, highOffset, min,
206 max, flat, fuzz, resolution, filter);
207 }
208
haveAxis(int32_t axisId)209 bool JoystickInputMapper::haveAxis(int32_t axisId) {
210 for (const std::pair<const int32_t, Axis>& pair : mAxes) {
211 const Axis& axis = pair.second;
212 if (axis.axisInfo.axis == axisId ||
213 (axis.axisInfo.mode == AxisInfo::MODE_SPLIT && axis.axisInfo.highAxis == axisId)) {
214 return true;
215 }
216 }
217 return false;
218 }
219
pruneAxes(bool ignoreExplicitlyMappedAxes)220 void JoystickInputMapper::pruneAxes(bool ignoreExplicitlyMappedAxes) {
221 while (mAxes.size() > PointerCoords::MAX_AXES) {
222 auto it = mAxes.begin();
223 if (ignoreExplicitlyMappedAxes && it->second.explicitlyMapped) {
224 continue;
225 }
226 ALOGI("Discarding joystick '%s' axis %d because there are too many axes.",
227 getDeviceName().c_str(), it->first);
228 mAxes.erase(it);
229 }
230 }
231
isCenteredAxis(int32_t axis)232 bool JoystickInputMapper::isCenteredAxis(int32_t axis) {
233 switch (axis) {
234 case AMOTION_EVENT_AXIS_X:
235 case AMOTION_EVENT_AXIS_Y:
236 case AMOTION_EVENT_AXIS_Z:
237 case AMOTION_EVENT_AXIS_RX:
238 case AMOTION_EVENT_AXIS_RY:
239 case AMOTION_EVENT_AXIS_RZ:
240 case AMOTION_EVENT_AXIS_HAT_X:
241 case AMOTION_EVENT_AXIS_HAT_Y:
242 case AMOTION_EVENT_AXIS_ORIENTATION:
243 case AMOTION_EVENT_AXIS_RUDDER:
244 case AMOTION_EVENT_AXIS_WHEEL:
245 return true;
246 default:
247 return false;
248 }
249 }
250
reset(nsecs_t when)251 std::list<NotifyArgs> JoystickInputMapper::reset(nsecs_t when) {
252 // Recenter all axes.
253 for (std::pair<const int32_t, Axis>& pair : mAxes) {
254 Axis& axis = pair.second;
255 axis.resetValue();
256 }
257
258 return InputMapper::reset(when);
259 }
260
process(const RawEvent & rawEvent)261 std::list<NotifyArgs> JoystickInputMapper::process(const RawEvent& rawEvent) {
262 std::list<NotifyArgs> out;
263 switch (rawEvent.type) {
264 case EV_ABS: {
265 auto it = mAxes.find(rawEvent.code);
266 if (it != mAxes.end()) {
267 Axis& axis = it->second;
268 float newValue, highNewValue;
269 switch (axis.axisInfo.mode) {
270 case AxisInfo::MODE_INVERT:
271 newValue = (axis.rawAxisInfo.maxValue - rawEvent.value) * axis.scale +
272 axis.offset;
273 highNewValue = 0.0f;
274 break;
275 case AxisInfo::MODE_SPLIT:
276 if (rawEvent.value < axis.axisInfo.splitValue) {
277 newValue = (axis.axisInfo.splitValue - rawEvent.value) * axis.scale +
278 axis.offset;
279 highNewValue = 0.0f;
280 } else if (rawEvent.value > axis.axisInfo.splitValue) {
281 newValue = 0.0f;
282 highNewValue =
283 (rawEvent.value - axis.axisInfo.splitValue) * axis.highScale +
284 axis.highOffset;
285 } else {
286 newValue = 0.0f;
287 highNewValue = 0.0f;
288 }
289 break;
290 default:
291 newValue = rawEvent.value * axis.scale + axis.offset;
292 highNewValue = 0.0f;
293 break;
294 }
295 axis.newValue = newValue;
296 axis.highNewValue = highNewValue;
297 }
298 break;
299 }
300
301 case EV_SYN:
302 switch (rawEvent.code) {
303 case SYN_REPORT:
304 out += sync(rawEvent.when, rawEvent.readTime, /*force=*/false);
305 break;
306 }
307 break;
308 }
309 return out;
310 }
311
sync(nsecs_t when,nsecs_t readTime,bool force)312 std::list<NotifyArgs> JoystickInputMapper::sync(nsecs_t when, nsecs_t readTime, bool force) {
313 std::list<NotifyArgs> out;
314 if (!filterAxes(force)) {
315 return out;
316 }
317
318 int32_t metaState = getContext()->getGlobalMetaState();
319 int32_t buttonState = 0;
320
321 PointerProperties pointerProperties;
322 pointerProperties.clear();
323 pointerProperties.id = 0;
324 pointerProperties.toolType = ToolType::UNKNOWN;
325
326 PointerCoords pointerCoords;
327 pointerCoords.clear();
328
329 for (std::pair<const int32_t, Axis>& pair : mAxes) {
330 const Axis& axis = pair.second;
331 setPointerCoordsAxisValue(&pointerCoords, axis.axisInfo.axis, axis.currentValue);
332 if (axis.axisInfo.mode == AxisInfo::MODE_SPLIT) {
333 setPointerCoordsAxisValue(&pointerCoords, axis.axisInfo.highAxis,
334 axis.highCurrentValue);
335 }
336 }
337
338 // Moving a joystick axis should not wake the device because joysticks can
339 // be fairly noisy even when not in use. On the other hand, pushing a gamepad
340 // button will likely wake the device.
341 // TODO: Use the input device configuration to control this behavior more finely.
342 uint32_t policyFlags = 0;
343 ui::LogicalDisplayId displayId = ui::LogicalDisplayId::INVALID;
344 if (getDeviceContext().getAssociatedViewport()) {
345 displayId = getDeviceContext().getAssociatedViewport()->displayId;
346 }
347
348 out.push_back(NotifyMotionArgs(getContext()->getNextId(), when, readTime, getDeviceId(),
349 AINPUT_SOURCE_JOYSTICK, displayId, policyFlags,
350 AMOTION_EVENT_ACTION_MOVE, 0, 0, metaState, buttonState,
351 MotionClassification::NONE, AMOTION_EVENT_EDGE_FLAG_NONE, 1,
352 &pointerProperties, &pointerCoords, 0, 0,
353 AMOTION_EVENT_INVALID_CURSOR_POSITION,
354 AMOTION_EVENT_INVALID_CURSOR_POSITION, 0, /*videoFrames=*/{}));
355 return out;
356 }
357
setPointerCoordsAxisValue(PointerCoords * pointerCoords,int32_t axis,float value)358 void JoystickInputMapper::setPointerCoordsAxisValue(PointerCoords* pointerCoords, int32_t axis,
359 float value) {
360 pointerCoords->setAxisValue(axis, value);
361 /* In order to ease the transition for developers from using the old axes
362 * to the newer, more semantically correct axes, we'll continue to produce
363 * values for the old axes as mirrors of the value of their corresponding
364 * new axes. */
365 int32_t compatAxis = getCompatAxis(axis);
366 if (compatAxis >= 0) {
367 pointerCoords->setAxisValue(compatAxis, value);
368 }
369 }
370
filterAxes(bool force)371 bool JoystickInputMapper::filterAxes(bool force) {
372 bool atLeastOneSignificantChange = force;
373 for (std::pair<const int32_t, Axis>& pair : mAxes) {
374 Axis& axis = pair.second;
375 if (force ||
376 hasValueChangedSignificantly(axis.filter, axis.newValue, axis.currentValue, axis.min,
377 axis.max)) {
378 axis.currentValue = axis.newValue;
379 atLeastOneSignificantChange = true;
380 }
381 if (axis.axisInfo.mode == AxisInfo::MODE_SPLIT) {
382 if (force ||
383 hasValueChangedSignificantly(axis.filter, axis.highNewValue, axis.highCurrentValue,
384 axis.min, axis.max)) {
385 axis.highCurrentValue = axis.highNewValue;
386 atLeastOneSignificantChange = true;
387 }
388 }
389 }
390 return atLeastOneSignificantChange;
391 }
392
hasValueChangedSignificantly(float filter,float newValue,float currentValue,float min,float max)393 bool JoystickInputMapper::hasValueChangedSignificantly(float filter, float newValue,
394 float currentValue, float min, float max) {
395 if (newValue != currentValue) {
396 // Filter out small changes in value unless the value is converging on the axis
397 // bounds or center point. This is intended to reduce the amount of information
398 // sent to applications by particularly noisy joysticks (such as PS3).
399 if (fabs(newValue - currentValue) > filter ||
400 hasMovedNearerToValueWithinFilteredRange(filter, newValue, currentValue, min) ||
401 hasMovedNearerToValueWithinFilteredRange(filter, newValue, currentValue, max) ||
402 hasMovedNearerToValueWithinFilteredRange(filter, newValue, currentValue, 0)) {
403 return true;
404 }
405 }
406 return false;
407 }
408
hasMovedNearerToValueWithinFilteredRange(float filter,float newValue,float currentValue,float thresholdValue)409 bool JoystickInputMapper::hasMovedNearerToValueWithinFilteredRange(float filter, float newValue,
410 float currentValue,
411 float thresholdValue) {
412 float newDistance = fabs(newValue - thresholdValue);
413 if (newDistance < filter) {
414 float oldDistance = fabs(currentValue - thresholdValue);
415 if (newDistance < oldDistance) {
416 return true;
417 }
418 }
419 return false;
420 }
421
422 } // namespace android
423