1 /* 2 * Copyright (C) 2012 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_CPUCONSUMER_H 18 #define ANDROID_GUI_CPUCONSUMER_H 19 20 #include <gui/ConsumerBase.h> 21 22 #include <ui/GraphicBuffer.h> 23 24 #include <utils/String8.h> 25 #include <utils/Vector.h> 26 #include <utils/threads.h> 27 28 29 namespace android { 30 31 class BufferQueue; 32 33 /** 34 * CpuConsumer is a BufferQueue consumer endpoint that allows direct CPU 35 * access to the underlying gralloc buffers provided by BufferQueue. Multiple 36 * buffers may be acquired by it at once, to be used concurrently by the 37 * CpuConsumer owner. Sets gralloc usage flags to be software-read-only. 38 * This queue is synchronous by default. 39 */ 40 41 class CpuConsumer : public ConsumerBase 42 { 43 public: 44 typedef ConsumerBase::FrameAvailableListener FrameAvailableListener; 45 46 struct LockedBuffer { 47 uint8_t *data; 48 uint32_t width; 49 uint32_t height; 50 PixelFormat format; 51 uint32_t stride; 52 Rect crop; 53 uint32_t transform; 54 uint32_t scalingMode; 55 int64_t timestamp; 56 android_dataspace dataSpace; 57 uint64_t frameNumber; 58 // this is the same as format, except for formats that are compatible with 59 // a flexible format (e.g. HAL_PIXEL_FORMAT_YCbCr_420_888). In the latter 60 // case this contains that flexible format 61 PixelFormat flexFormat; 62 // Values below are only valid when using HAL_PIXEL_FORMAT_YCbCr_420_888 63 // or compatible format, in which case LockedBuffer::data 64 // contains the Y channel, and stride is the Y channel stride. For other 65 // formats, these will all be 0. 66 uint8_t *dataCb; 67 uint8_t *dataCr; 68 uint32_t chromaStride; 69 uint32_t chromaStep; 70 }; 71 72 // Create a new CPU consumer. The maxLockedBuffers parameter specifies 73 // how many buffers can be locked for user access at the same time. 74 CpuConsumer(const sp<IGraphicBufferConsumer>& bq, 75 size_t maxLockedBuffers, bool controlledByApp = false); 76 77 virtual ~CpuConsumer(); 78 79 // set the name of the CpuConsumer that will be used to identify it in 80 // log messages. 81 void setName(const String8& name); 82 83 // Gets the next graphics buffer from the producer and locks it for CPU use, 84 // filling out the passed-in locked buffer structure with the native pointer 85 // and metadata. Returns BAD_VALUE if no new buffer is available, and 86 // NOT_ENOUGH_DATA if the maximum number of buffers is already locked. 87 // 88 // Only a fixed number of buffers can be locked at a time, determined by the 89 // construction-time maxLockedBuffers parameter. If INVALID_OPERATION is 90 // returned by lockNextBuffer, then old buffers must be returned to the queue 91 // by calling unlockBuffer before more buffers can be acquired. 92 status_t lockNextBuffer(LockedBuffer *nativeBuffer); 93 94 // Returns a locked buffer to the queue, allowing it to be reused. Since 95 // only a fixed number of buffers may be locked at a time, old buffers must 96 // be released by calling unlockBuffer to ensure new buffers can be acquired by 97 // lockNextBuffer. 98 status_t unlockBuffer(const LockedBuffer &nativeBuffer); 99 100 private: 101 // Maximum number of buffers that can be locked at a time 102 size_t mMaxLockedBuffers; 103 104 status_t releaseAcquiredBufferLocked(size_t lockedIdx); 105 106 virtual void freeBufferLocked(int slotIndex); 107 108 // Tracking for buffers acquired by the user 109 struct AcquiredBuffer { 110 // Need to track the original mSlot index and the buffer itself because 111 // the mSlot entry may be freed/reused before the acquired buffer is 112 // released. 113 int mSlot; 114 sp<GraphicBuffer> mGraphicBuffer; 115 void *mBufferPointer; 116 AcquiredBufferAcquiredBuffer117 AcquiredBuffer() : 118 mSlot(BufferQueue::INVALID_BUFFER_SLOT), 119 mBufferPointer(NULL) { 120 } 121 }; 122 Vector<AcquiredBuffer> mAcquiredBuffers; 123 124 // Count of currently locked buffers 125 size_t mCurrentLockedBuffers; 126 127 }; 128 129 } // namespace android 130 131 #endif // ANDROID_GUI_CPUCONSUMER_H 132