Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2017 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 | package android.hardware; |
| 17 | |
| 18 | import android.annotation.IntDef; |
| 19 | import android.os.MemoryFile; |
| 20 | |
| 21 | import dalvik.system.CloseGuard; |
| 22 | |
| 23 | import java.io.IOException; |
| 24 | import java.lang.annotation.Retention; |
| 25 | import java.lang.annotation.RetentionPolicy; |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 26 | import java.nio.channels.Channel; |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 27 | import java.util.concurrent.atomic.AtomicBoolean; |
| 28 | |
| 29 | /** |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 30 | * Class representing a sensor direct channel. Use |
| 31 | * {@link SensorManager#createDirectChannel(android.os.MemoryFile)} or |
| 32 | * {@link SensorManager#createDirectChannel(android.hardware.HardwareBuffer)} |
| 33 | * to obtain an object. The channel object can be then configured |
| 34 | * (see {@link #configure(Sensor, int)}) |
| 35 | * to start delivery of sensor events into shared memory buffer. |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 36 | */ |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 37 | public final class SensorDirectChannel implements Channel { |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 38 | |
| 39 | // shared memory types |
| 40 | |
| 41 | /** @hide */ |
| 42 | @Retention(RetentionPolicy.SOURCE) |
Jeff Sharkey | ce8db99 | 2017-12-13 20:05:05 -0700 | [diff] [blame] | 43 | @IntDef(flag = true, prefix = { "TYPE_" }, value = { |
| 44 | TYPE_MEMORY_FILE, |
| 45 | TYPE_HARDWARE_BUFFER |
| 46 | }) |
| 47 | public @interface MemoryType {} |
| 48 | |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 49 | /** |
| 50 | * Shared memory type ashmem, wrapped in MemoryFile object. |
| 51 | * |
| 52 | * @see SensorManager#createDirectChannel(MemoryFile) |
| 53 | */ |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 54 | public static final int TYPE_MEMORY_FILE = 1; |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 55 | |
| 56 | /** |
| 57 | * Shared memory type wrapped by HardwareBuffer object. |
| 58 | * |
| 59 | * @see SensorManager#createDirectChannel(HardwareBuffer) |
| 60 | */ |
| 61 | public static final int TYPE_HARDWARE_BUFFER = 2; |
| 62 | |
| 63 | // sensor rate levels |
| 64 | |
| 65 | /** @hide */ |
| 66 | @Retention(RetentionPolicy.SOURCE) |
Jeff Sharkey | ce8db99 | 2017-12-13 20:05:05 -0700 | [diff] [blame] | 67 | @IntDef(flag = true, prefix = { "RATE_" }, value = { |
| 68 | RATE_STOP, |
| 69 | RATE_NORMAL, |
| 70 | RATE_FAST, |
| 71 | RATE_VERY_FAST |
| 72 | }) |
| 73 | public @interface RateLevel {} |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 74 | |
| 75 | /** |
| 76 | * Sensor stopped (no event output). |
| 77 | * |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 78 | * @see #configure(Sensor, int) |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 79 | */ |
| 80 | public static final int RATE_STOP = 0; |
| 81 | /** |
| 82 | * Sensor operates at nominal rate of 50Hz. |
| 83 | * |
| 84 | * The actual rate is expected to be between 55% to 220% of nominal rate, thus between 27.5Hz to |
| 85 | * 110Hz. |
| 86 | * |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 87 | * @see #configure(Sensor, int) |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 88 | */ |
| 89 | public static final int RATE_NORMAL = 1; //50Hz |
| 90 | /** |
| 91 | * Sensor operates at nominal rate of 200Hz. |
| 92 | * |
| 93 | * The actual rate is expected to be between 55% to 220% of nominal rate, thus between 110Hz to |
| 94 | * 440Hz. |
| 95 | * |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 96 | * @see #configure(Sensor, int) |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 97 | */ |
| 98 | public static final int RATE_FAST = 2; // ~200Hz |
| 99 | /** |
| 100 | * Sensor operates at nominal rate of 800Hz. |
| 101 | * |
| 102 | * The actual rate is expected to be between 55% to 220% of nominal rate, thus between 440Hz to |
| 103 | * 1760Hz. |
| 104 | * |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 105 | * @see #configure(Sensor, int) |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 106 | */ |
| 107 | public static final int RATE_VERY_FAST = 3; // ~800Hz |
| 108 | |
| 109 | /** |
| 110 | * Determine if a channel is still valid. A channel is invalidated after {@link #close()} is |
| 111 | * called. |
| 112 | * |
| 113 | * @return <code>true</code> if channel is valid. |
| 114 | */ |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 115 | @Override |
| 116 | public boolean isOpen() { |
Peng Xu | fa2672b | 2016-12-07 03:54:44 -0800 | [diff] [blame] | 117 | return !mClosed.get(); |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 118 | } |
| 119 | |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 120 | /** @removed */ |
| 121 | @Deprecated |
| 122 | public boolean isValid() { |
| 123 | return isOpen(); |
| 124 | } |
| 125 | |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 126 | /** |
| 127 | * Close sensor direct channel. |
| 128 | * |
| 129 | * Stop all active sensor in the channel and free sensor system resource related to channel. |
| 130 | * Shared memory used for creating the direct channel need to be closed or freed separately. |
| 131 | * |
| 132 | * @see SensorManager#createDirectChannel(MemoryFile) |
| 133 | * @see SensorManager#createDirectChannel(HardwareBuffer) |
| 134 | */ |
| 135 | @Override |
| 136 | public void close() { |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 137 | if (mClosed.compareAndSet(false, true)) { |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 138 | mCloseGuard.close(); |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 139 | // actual close action |
| 140 | mManager.destroyDirectChannel(this); |
| 141 | } |
| 142 | } |
| 143 | |
Peng Xu | 3c8c6a4 | 2017-04-06 18:37:56 -0700 | [diff] [blame] | 144 | /** |
| 145 | * Configure sensor rate or stop sensor report. |
| 146 | * |
| 147 | * To start event report of a sensor, or change rate of existing report, call this function with |
| 148 | * rateLevel other than {@link android.hardware.SensorDirectChannel#RATE_STOP}. Sensor events |
| 149 | * will be added into a queue formed by the shared memory used in creation of direction channel. |
| 150 | * Each element of the queue has size of 104 bytes and represents a sensor event. Data |
| 151 | * structure of an element (all fields in little-endian): |
| 152 | * |
| 153 | * <pre> |
| 154 | * offset type name |
| 155 | * ------------------------------------------------------------------------ |
| 156 | * 0x0000 int32_t size (always 104) |
| 157 | * 0x0004 int32_t sensor report token |
| 158 | * 0x0008 int32_t type (see SensorType) |
| 159 | * 0x000C uint32_t atomic counter |
| 160 | * 0x0010 int64_t timestamp (see Event) |
| 161 | * 0x0018 float[16]/int64_t[8] data (data type depends on sensor type) |
| 162 | * 0x0058 int32_t[4] reserved (set to zero) |
| 163 | * </pre> |
| 164 | * |
| 165 | * There are no head or tail pointers. The sequence and frontier of new sensor events is |
| 166 | * determined by the atomic counter, which counts from 1 after creation of direct channel and |
| 167 | * increments 1 for each new event. Atomic counter will wrap back to 1 after it reaches |
| 168 | * UINT32_MAX, skipping value 0 to avoid confusion with uninitialized memory. The writer in |
| 169 | * sensor system will wrap around from the start of shared memory region when it reaches the |
| 170 | * end. If size of memory region is not a multiple of size of element (104 bytes), the residual |
| 171 | * is not used at the end. Function returns a positive sensor report token on success. This |
| 172 | * token can be used to differentiate sensor events from multiple sensor of the same type. For |
| 173 | * example, if there are two accelerometers in the system A and B, it is guaranteed different |
| 174 | * report tokens will be returned when starting sensor A and B. |
| 175 | * |
| 176 | * To stop a sensor, call this function with rateLevel equal {@link |
| 177 | * android.hardware.SensorDirectChannel#RATE_STOP}. If the sensor parameter is left to be null, |
| 178 | * this will stop all active sensor report associated with the direct channel specified. |
| 179 | * Function return 1 on success or 0 on failure. |
| 180 | * |
| 181 | * @param sensor A {@link android.hardware.Sensor} object to denote sensor to be operated. |
| 182 | * @param rateLevel rate level defined in {@link android.hardware.SensorDirectChannel}. |
| 183 | * @return * starting report or changing rate: positive sensor report token on success, |
| 184 | * 0 on failure; |
| 185 | * * stopping report: 1 on success, 0 on failure. |
| 186 | * @throws NullPointerException when channel is null. |
| 187 | */ |
| 188 | public int configure(Sensor sensor, @RateLevel int rateLevel) { |
| 189 | return mManager.configureDirectChannelImpl(this, sensor, rateLevel); |
| 190 | } |
| 191 | |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 192 | /** @hide */ |
| 193 | SensorDirectChannel(SensorManager manager, int id, int type, long size) { |
| 194 | mManager = manager; |
Peng Xu | fa2672b | 2016-12-07 03:54:44 -0800 | [diff] [blame] | 195 | mNativeHandle = id; |
| 196 | mType = type; |
| 197 | mSize = size; |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 198 | mCloseGuard.open("SensorDirectChannel"); |
| 199 | } |
| 200 | |
Peng Xu | fa2672b | 2016-12-07 03:54:44 -0800 | [diff] [blame] | 201 | /** @hide */ |
| 202 | int getNativeHandle() { |
| 203 | return mNativeHandle; |
| 204 | } |
| 205 | |
| 206 | /** |
Peng Xu | 7d96fa0 | 2017-03-04 16:15:45 -0800 | [diff] [blame] | 207 | * This function encode handle information in {@link android.os.MemoryFile} into a long array to |
| 208 | * be passed down to native methods. |
Peng Xu | fa2672b | 2016-12-07 03:54:44 -0800 | [diff] [blame] | 209 | * |
| 210 | * @hide */ |
| 211 | static long[] encodeData(MemoryFile ashmem) { |
| 212 | int fd; |
| 213 | try { |
| 214 | fd = ashmem.getFileDescriptor().getInt$(); |
| 215 | } catch (IOException e) { |
| 216 | fd = -1; |
| 217 | } |
| 218 | return new long[] { 1 /*numFds*/, 0 /*numInts*/, fd }; |
| 219 | } |
| 220 | |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 221 | @Override |
| 222 | protected void finalize() throws Throwable { |
| 223 | try { |
Narayan Kamath | 492e9e8 | 2017-03-22 14:28:08 +0000 | [diff] [blame] | 224 | if (mCloseGuard != null) { |
| 225 | mCloseGuard.warnIfOpen(); |
| 226 | } |
| 227 | |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 228 | close(); |
| 229 | } finally { |
| 230 | super.finalize(); |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | private final AtomicBoolean mClosed = new AtomicBoolean(); |
| 235 | private final CloseGuard mCloseGuard = CloseGuard.get(); |
| 236 | private final SensorManager mManager; |
Peng Xu | fa2672b | 2016-12-07 03:54:44 -0800 | [diff] [blame] | 237 | private final int mNativeHandle; |
| 238 | private final long mSize; |
| 239 | private final int mType; |
Peng Xu | ccf0c8e | 2017-01-17 22:16:21 -0800 | [diff] [blame] | 240 | } |