graphics/mapper/2.0/IMapper.hal

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.hardware.graphics.mapper@2.0;

import android.hardware.graphics.common@1.0::PixelFormat;
import android.hardware.graphics.allocator@2.0;

interface IMapper {
    struct Rect {
        int32_t left;
        int32_t top;
        int32_t width;
        int32_t height;
    };

    /**
     * Adds a reference to the given buffer handle.
     *
     * A buffer handle received from a remote process or exported by
     * IAllocator::exportHandle is unknown to the mapper. There is also no
     * guarantee that the buffer's backing store will stay alive. This
     * function must be called at least once in both cases to intrdouce the
     * buffer handle to the mapper and to secure the backing store. It may
     * also be called more than once to increase the reference count if two
     * components in the same process want to interact with the buffer
     * independently.
     *
     * @param bufferHandle is the buffer to which a reference must be added.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid
     *                  NO_RESOURCES when it is not possible to add a
     *                               reference to this buffer at this time
     */
    @entry
    @callflow(next="*")
    retain(handle bufferHandle) generates (Error error);

    /**
     * Removes a reference from the given buffer buffer.
     *
     * If no references remain, the buffer handle must be freed with
     * native_handle_close/native_handle_delete by the mapper. When the last
     * buffer handle referring to a particular backing store is freed, that
     * backing store must also be freed.
     *
     * @param bufferHandle is the buffer from which a reference must be
     *        removed.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     */
    @exit
    release(handle bufferHandle) generates (Error error);

    /**
     * Gets the width and height of the buffer in pixels.
     *
     * See IAllocator::BufferDescriptorInfo for more information.
     *
     * @param bufferHandle is the buffer from which to get the dimensions.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return width is the width of the buffer in pixels.
     * @return height is the height of the buffer in pixels.
     */
    @callflow(next="*")
    getDimensions(handle bufferHandle)
       generates (Error error,
                  uint32_t width,
                  uint32_t height);

    /**
     * Gets the format of the buffer.
     *
     * See IAllocator::BufferDescriptorInfo for more information.
     *
     * @param bufferHandle is the buffer from which to get format.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return format is the format of the buffer.
     */
    @callflow(next="*")
    getFormat(handle bufferHandle)
        generates (Error error,
                   PixelFormat format);

    /**
     * Gets the number of layers of the buffer.
     *
     * See IAllocator::BufferDescriptorInfo for more information.
     *
     * @param bufferHandle is the buffer from which to get format.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return layerCount is the number of layers of the buffer.
     */
    @callflow(next="*")
    getLayerCount(handle bufferHandle)
       generates (Error error,
                  uint32_t layerCount);

    /**
     * Gets the producer usage flags which were used to allocate this buffer.
     *
     * See IAllocator::BufferDescriptorInfo for more information.
     *
     * @param bufferHandle is the buffer from which to get the producer usage
     *        flags.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return usageMask contains the producer usage flags of the buffer.
     */
    @callflow(next="*")
    getProducerUsageMask(handle bufferHandle)
              generates (Error error,
                         uint64_t usageMask);

    /**
     * Gets the consumer usage flags which were used to allocate this buffer.
     *
     * See IAllocator::BufferDescriptorInfo for more information.
     *
     * @param bufferHandle is the buffer from which to get the consumer usage
     *        flags.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return usageMask contains the consumer usage flags of the buffer.
     */
    @callflow(next="*")
    getConsumerUsageMask(handle bufferHandle)
              generates (Error error,
                         uint64_t usageMask);

    /**
     * Gets a value that uniquely identifies the backing store of the given
     * buffer.
     *
     * Buffers which share a backing store should return the same value from
     * this function. If the buffer is present in more than one process, the
     * backing store value for that buffer is not required to be the same in
     * every process.
     *
     * @param device is the mapper device.
     * @param bufferHandle is the buffer from which to get the backing store
     *        identifier.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return store is the backing store identifier for this buffer.
     */
    @callflow(next="*")
    getBackingStore(handle bufferHandle)
         generates (Error error,
                    BackingStore store);

    /**
     * Gets the stride of the buffer in pixels.
     *
     * The stride is the offset in pixel-sized elements between the same
     * column in two adjacent rows of pixels. This may not be equal to the
     * width of the buffer.
     *
     * @param device is the mapper device.
     * @param bufferHandle is the buffer from which to get the stride.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     *                  UNDEFINED when the notion of a stride is not
     *                            meaningful for the buffer format.
     * @return store is the stride in pixels.
     */
    @callflow(next="*")
    getStride(handle bufferHandle)
        generates (Error error,
                   uint32_t stride);

    /**
     * Locks the given buffer for the specified CPU usage.
     *
     * Exactly one of producerUsageMask and consumerUsageMask must be 0. The
     * usage which is not 0 must be one of the *Usage::CPU* values, as
     * applicable. Locking a buffer for a non-CPU usage is not supported.
     *
     * Locking the same buffer simultaneously from multiple threads is
     * permitted, but if any of the threads attempt to lock the buffer for
     * writing, the behavior is undefined, except that it must not cause
     * process termination or block the client indefinitely. Leaving the
     * buffer content in an indeterminate state or returning an error are both
     * acceptable.
     *
     * The client must not modify the content of the buffer outside of
     * accessRegion, and the device need not guarantee that content outside of
     * accessRegion is valid for reading. The result of reading or writing
     * outside of accessRegion is undefined, except that it must not cause
     * process termination.
     *
     * data will be filled with a pointer to the locked buffer memory. This
     * address will represent the top-left corner of the entire buffer, even
     * if accessRegion does not begin at the top-left corner.
     *
     * acquireFence is a file descriptor referring to a acquire sync fence
     * object, which will be signaled when it is safe for the device to access
     * the contents of the buffer (prior to locking). If it is already safe to
     * access the buffer contents, -1 may be passed instead.
     *
     * @param bufferHandle is the buffer to lock.
     * @param producerUsageMask contains the producer usage flags to request;
     *        either this or consumerUsagemask must be 0, and the other must
     *        be a CPU usage.
     * @param consumerUsageMask contains the consumer usage flags to request;
     *        either this or producerUsageMask must be 0, and the other must
     *        be a CPU usage.
     * @param accessRegion is the portion of the buffer that the client
     *        intends to access.
     * @param acquireFence is a sync fence file descriptor as described above.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     *                  BAD_VALUE when neither or both of producerUsageMask
     *                            and consumerUsageMask were 0, or the usage
     *                            which was not 0 was not a CPU usage.
     *                  NO_RESOURCES when the buffer cannot be locked at this
     *                               time, but locking may succeed at a future
     *                               time.
     *                  UNSUPPORTED when the buffer cannot be locked with the
     *                              given usage, and any future attempts at
     *                              locking will also fail.
     * @return data will be filled with a CPU-accessible pointer to the buffer
     *         data.
     */
    @callflow(next="unlock")
    lock(handle bufferHandle,
         uint64_t producerUsageMask,
         uint64_t consumerUsageMask,
         Rect accessRegion,
         handle acquireFence)
        generates (Error error,
                   pointer data);

    /**
     * This is largely the same as lock(), except that instead of returning a
     * pointer directly to the buffer data, it returns an FlexLayout struct
     * describing how to access the data planes.
     *
     * This function must work on buffers with PixelFormat::YCbCr_*_888 if
     * supported by the device, as well as with any other formats requested by
     * multimedia codecs when they are configured with a
     * flexible-YUV-compatible color format.
     *
     * This function may also be called on buffers of other formats, including
     * non-YUV formats, but if the buffer format is not compatible with a
     * flexible representation, it may return UNSUPPORTED.
     *
     * @param device is the mapper device.
     * @param bufferHandle is the buffer to lock.
     * @param producerUsageMask contains the producer usage flags to request;
     *        either this or consumerUsagemask must be 0, and the other must
     *        be a CPU usage.
     * @param consumerUsageMask contains the consumer usage flags to request;
     *        either this or producerUsageMask must be 0, and the other must
     *        be a CPU usage.
     * @param accessRegion is the portion of the buffer that the client
     *        intends to access.
     * @param acquireFence is a sync fence file descriptor as described in
     *        lock().
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     *                  BAD_VALUE when neither or both of producerUsageMask
     *                            and consumerUsageMask were 0, or the usage
     *                            which was not 0 was not a CPU usage.
     *                  NO_RESOURCES when the buffer cannot be locked at this
     *                               time, but locking may succeed at a future
     *                               time.
     *                  UNSUPPORTED when the buffer cannot be locked with the
     *                              given usage, and any future attempts at
     *                              locking will also fail.
     * @return flexLayout will be filled with the description of the planes in
     *         the buffer.
     */
    @callflow(next="unlock")
    lockFlex(handle bufferHandle,
             uint64_t producerUsageMask,
             uint64_t consumerUsageMask,
             Rect accessRegion,
             handle acquireFence)
        generates (Error error,
                   FlexLayout layout);

    /**
     * This function indicates to the device that the client will be done with
     * the buffer when releaseFence signals.
     *
     * releaseFence will be filled with a file descriptor referring to a
     * release sync fence object, which will be signaled when it is safe to
     * access the contents of the buffer (after the buffer has been unlocked).
     * If it is already safe to access the buffer contents, then -1 may be
     * returned instead.
     *
     * This function is used to unlock both buffers locked by lock() and those
     * locked by lockFlex().
     *
     * @param device is the mapper device.
     * @param bufferHandle is the buffer to unlock.
     * @return error is NONE upon success. Otherwise,
     *                  BAD_BUFFER when the buffer handle is invalid.
     * @return releaseFence is a sync fence file descriptor as described
     *         above.
     */
    @callflow(next="*")
    unlock(handle bufferHandle)
        generates (Error error,
                   handle releaseFence);
};