1 /* 2 * Copyright 2014 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 #ifndef ANDROID_GUI_BUFFERQUEUEPRODUCER_H 18 #define ANDROID_GUI_BUFFERQUEUEPRODUCER_H 19 20 #include <gui/BufferQueueDefs.h> 21 #include <gui/IGraphicBufferProducer.h> 22 23 namespace android { 24 25 class BufferSlot; 26 27 class BufferQueueProducer : public BnGraphicBufferProducer, 28 private IBinder::DeathRecipient { 29 public: 30 friend class BufferQueue; // Needed to access binderDied 31 32 BufferQueueProducer(const sp<BufferQueueCore>& core); 33 virtual ~BufferQueueProducer(); 34 35 // requestBuffer returns the GraphicBuffer for slot N. 36 // 37 // In normal operation, this is called the first time slot N is returned 38 // by dequeueBuffer. It must be called again if dequeueBuffer returns 39 // flags indicating that previously-returned buffers are no longer valid. 40 virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf); 41 42 // setBufferCount updates the number of available buffer slots. If this 43 // method succeeds, buffer slots will be both unallocated and owned by 44 // the BufferQueue object (i.e. they are not owned by the producer or 45 // consumer). 46 // 47 // This will fail if the producer has dequeued any buffers, or if 48 // bufferCount is invalid. bufferCount must generally be a value 49 // between the minimum undequeued buffer count (exclusive) and NUM_BUFFER_SLOTS 50 // (inclusive). It may also be set to zero (the default) to indicate 51 // that the producer does not wish to set a value. The minimum value 52 // can be obtained by calling query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS, 53 // ...). 54 // 55 // This may only be called by the producer. The consumer will be told 56 // to discard buffers through the onBuffersReleased callback. 57 virtual status_t setBufferCount(int bufferCount); 58 59 // dequeueBuffer gets the next buffer slot index for the producer to use. 60 // If a buffer slot is available then that slot index is written to the 61 // location pointed to by the buf argument and a status of OK is returned. 62 // If no slot is available then a status of -EBUSY is returned and buf is 63 // unmodified. 64 // 65 // The outFence parameter will be updated to hold the fence associated with 66 // the buffer. The contents of the buffer must not be overwritten until the 67 // fence signals. If the fence is Fence::NO_FENCE, the buffer may be 68 // written immediately. 69 // 70 // The width and height parameters must be no greater than the minimum of 71 // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv). 72 // An error due to invalid dimensions might not be reported until 73 // updateTexImage() is called. If width and height are both zero, the 74 // default values specified by setDefaultBufferSize() are used instead. 75 // 76 // The pixel formats are enumerated in graphics.h, e.g. 77 // HAL_PIXEL_FORMAT_RGBA_8888. If the format is 0, the default format 78 // will be used. 79 // 80 // The usage argument specifies gralloc buffer usage flags. The values 81 // are enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER. These 82 // will be merged with the usage flags specified by setConsumerUsageBits. 83 // 84 // The return value may be a negative error value or a non-negative 85 // collection of flags. If the flags are set, the return values are 86 // valid, but additional actions must be performed. 87 // 88 // If IGraphicBufferProducer::BUFFER_NEEDS_REALLOCATION is set, the 89 // producer must discard cached GraphicBuffer references for the slot 90 // returned in buf. 91 // If IGraphicBufferProducer::RELEASE_ALL_BUFFERS is set, the producer 92 // must discard cached GraphicBuffer references for all slots. 93 // 94 // In both cases, the producer will need to call requestBuffer to get a 95 // GraphicBuffer handle for the returned slot. 96 virtual status_t dequeueBuffer(int *outSlot, sp<Fence>* outFence, bool async, 97 uint32_t width, uint32_t height, uint32_t format, uint32_t usage); 98 99 // See IGraphicBufferProducer::detachBuffer 100 virtual status_t detachBuffer(int slot); 101 102 // See IGraphicBufferProducer::detachNextBuffer 103 virtual status_t detachNextBuffer(sp<GraphicBuffer>* outBuffer, 104 sp<Fence>* outFence); 105 106 // See IGraphicBufferProducer::attachBuffer 107 virtual status_t attachBuffer(int* outSlot, const sp<GraphicBuffer>& buffer); 108 109 // queueBuffer returns a filled buffer to the BufferQueue. 110 // 111 // Additional data is provided in the QueueBufferInput struct. Notably, 112 // a timestamp must be provided for the buffer. The timestamp is in 113 // nanoseconds, and must be monotonically increasing. Its other semantics 114 // (zero point, etc) are producer-specific and should be documented by the 115 // producer. 116 // 117 // The caller may provide a fence that signals when all rendering 118 // operations have completed. Alternatively, NO_FENCE may be used, 119 // indicating that the buffer is ready immediately. 120 // 121 // Some values are returned in the output struct: the current settings 122 // for default width and height, the current transform hint, and the 123 // number of queued buffers. 124 virtual status_t queueBuffer(int slot, 125 const QueueBufferInput& input, QueueBufferOutput* output); 126 127 // cancelBuffer returns a dequeued buffer to the BufferQueue, but doesn't 128 // queue it for use by the consumer. 129 // 130 // The buffer will not be overwritten until the fence signals. The fence 131 // will usually be the one obtained from dequeueBuffer. 132 virtual void cancelBuffer(int slot, const sp<Fence>& fence); 133 134 // Query native window attributes. The "what" values are enumerated in 135 // window.h (e.g. NATIVE_WINDOW_FORMAT). 136 virtual int query(int what, int* outValue); 137 138 // connect attempts to connect a producer API to the BufferQueue. This 139 // must be called before any other IGraphicBufferProducer methods are 140 // called except for getAllocator. A consumer must already be connected. 141 // 142 // This method will fail if connect was previously called on the 143 // BufferQueue and no corresponding disconnect call was made (i.e. if 144 // it's still connected to a producer). 145 // 146 // APIs are enumerated in window.h (e.g. NATIVE_WINDOW_API_CPU). 147 virtual status_t connect(const sp<IProducerListener>& listener, 148 int api, bool producerControlledByApp, QueueBufferOutput* output); 149 150 // disconnect attempts to disconnect a producer API from the BufferQueue. 151 // Calling this method will cause any subsequent calls to other 152 // IGraphicBufferProducer methods to fail except for getAllocator and connect. 153 // Successfully calling connect after this will allow the other methods to 154 // succeed again. 155 // 156 // This method will fail if the the BufferQueue is not currently 157 // connected to the specified producer API. 158 virtual status_t disconnect(int api); 159 160 // Attaches a sideband buffer stream to the IGraphicBufferProducer. 161 // 162 // A sideband stream is a device-specific mechanism for passing buffers 163 // from the producer to the consumer without using dequeueBuffer/ 164 // queueBuffer. If a sideband stream is present, the consumer can choose 165 // whether to acquire buffers from the sideband stream or from the queued 166 // buffers. 167 // 168 // Passing NULL or a different stream handle will detach the previous 169 // handle if any. 170 virtual status_t setSidebandStream(const sp<NativeHandle>& stream); 171 172 // See IGraphicBufferProducer::allocateBuffers 173 virtual void allocateBuffers(bool async, uint32_t width, uint32_t height, 174 uint32_t format, uint32_t usage); 175 176 private: 177 // This is required by the IBinder::DeathRecipient interface 178 virtual void binderDied(const wp<IBinder>& who); 179 180 // waitForFreeSlotThenRelock finds the oldest slot in the FREE state. It may 181 // block if there are no available slots and we are not in non-blocking 182 // mode (producer and consumer controlled by the application). If it blocks, 183 // it will release mCore->mMutex while blocked so that other operations on 184 // the BufferQueue may succeed. 185 status_t waitForFreeSlotThenRelock(const char* caller, bool async, 186 int* found, status_t* returnFlags) const; 187 188 sp<BufferQueueCore> mCore; 189 190 // This references mCore->mSlots. Lock mCore->mMutex while accessing. 191 BufferQueueDefs::SlotsType& mSlots; 192 193 // This is a cached copy of the name stored in the BufferQueueCore. 194 // It's updated during connect and dequeueBuffer (which should catch 195 // most updates). 196 String8 mConsumerName; 197 198 uint32_t mStickyTransform; 199 200 }; // class BufferQueueProducer 201 202 } // namespace android 203 204 #endif 205