ACX 多堆疊跨驅動程序通訊
本主題提供音訊類別 eXtensions （ACX） 多重堆疊跨驅動程式通訊的摘要。
如需 ACX 的一般資訊，請參閱 ACX 音訊類別延伸模組概觀 和 ACX 物件的摘要。
如需 ACX 目標的基本資訊，請參閱 ACX 目標和驅動程式同步 處理和 ACX IO 要求封包 IRP。
單一堆疊音訊驅動程式
舊版 PortCls 和 KS 音訊類別驅動程式僅支援「單一堆棧」音訊驅動程式。 舊版音訊架構只會與一個迷你埠驅動程序進行通訊和介面。 迷你埠驅動程式可在必要時管理與其他驅動程式堆疊的通訊和同步處理。
ACX 完全支援單一堆疊音訊驅動程式。 音訊開發人員可以將目前的 Portcls 和 KS 迷你埠驅動程式取代為 ACX 型驅動程式，同時與其他堆疊保持相同的行為。 雖然音訊子系統使用多音訊堆疊，但較好的方法是使用 ACX 中的 多堆疊 支援，並讓 ACX 將這些堆疊同步處理在一起，如本主題的下一節所述。
多堆疊音訊驅動程式 - 元件化
音訊路徑通常會經歷由不同驅動程式堆疊處理的多個硬體元件，以建立完整的音訊體驗。 系統通常會讓不同音訊技術廠商實作的 DSP、CODEC 和 AMP 功能，如下圖所示。
在沒有妥善定義標準的 多堆疊 架構中，每個廠商都會被迫定義自己的專屬介面和通訊協定。 ACX 的目標是藉由取得這些堆疊之間的同步處理擁有權，併為驅動程式提供簡單的可重複使用模式，以便開發 多堆疊 音訊驅動程式。
使用 ACX 時，可以使用下列軟體架構支援範例系統 DSP、CODEC 和 AMP 硬體設計。
請注意，您可以使用任何類型的元件類型，而不是顯示的 DSP、CODEC 和 AMP，因為 ACX 不相依於任何特定元件類型，或元件的特定排列。
第三方驅動程式會透過 ACX 與定義完善的通訊協定彼此通訊。 這種方法的其中一個優點是，單一堆疊可以取代為來自不同廠商的另一個堆疊，而不需要變更連續的軟體堆疊。 音訊類別延伸模組 （ACX） 架構的主要目標之一，是簡化開發來自不同廠商元件 多堆疊 音訊驅動程式所需的工作。
ACX 目標通訊範例 - 線路
此範例程式代碼示範如何使用 AcxTargetCircuit 和 AcxTargetCircuitGetWdfIoTarget 來與不同堆棧公開的遠端線路通訊。 如需 ACX 線路的詳細資訊，請參閱 acxcircuit.h。
這個相當複雜的匯總工具會找出線路，然後使用 AcxTargetCircuitGetWdfIoTarget 建立 ioTarget。 然後，它會設定自定義 WDF 傳送選項，並異步傳送要求。 最後，它會檢查傳送的狀態，以確認已傳送要求。
NTSTATUS
Aggregator_SendModuleCommand(
_In_ PAGGREGATOR_RENDER_CIRCUIT_CONTEXT CircuitCtx,
_In_ ACX_REQUEST_PARAMETERS Params,
_Out_ ULONG_PTR * OutSize
)
{
NTSTATUS status = STATUS_NOT_SUPPORTED;
PKSAUDIOMODULE_PROPERTY moduleProperty = nullptr;
ULONG aggregationDeviceIndex = 0;
PLIST_ENTRY ple;
*OutSize = 0;
moduleProperty = CONTAINING_RECORD(Params.Parameters.Property.Control, KSAUDIOMODULE_PROPERTY, ClassId);;
aggregationDeviceIndex = AUDIOMODULE_GET_AGGDEVICEID(moduleProperty->InstanceId);
ple = CircuitCtx->AggregatorCircuit->AggregatorEndpoint->AudioPaths[aggregationDeviceIndex]->TargetCircuitList.Flink;
while (ple != &CircuitCtx->AggregatorCircuit->AggregatorEndpoint->AudioPaths[aggregationDeviceIndex]->TargetCircuitList)
{
PAUDIO_CIRCUIT circuit = (PAUDIO_CIRCUIT)CONTAINING_RECORD(ple, AUDIO_CIRCUIT, ListEntry);
if (circuit->Modules)
{
for(ULONG i = 0; i < circuit->Modules->Count; i++)
{
PACX_AUDIOMODULE_DESCRIPTOR descriptor = ((PACX_AUDIOMODULE_DESCRIPTOR)(circuit->Modules + 1) + i);
// we've identified which aggregation device this call is targeting,
// now locate which circuit implements this module. Within an aggregated device,
// the module class id + instance id must uniquely identify a module. There should
// never be duplicates.
if (IsEqualGUIDAligned(descriptor->ClassId, moduleProperty->ClassId) &&
descriptor->InstanceId == moduleProperty->InstanceId)
{
WDFREQUEST request = NULL;
WDF_REQUEST_SEND_OPTIONS sendOptions;
WDF_OBJECT_ATTRIBUTES attributes;
WDFIOTARGET ioTarget;
// We've now identified which aggregated device this call is targeting.
// The cached module information contains the ID adjusted with the aggregation device
// index. remove the aggregation device index before forwarding the call to the aggregated circuit.
moduleProperty->InstanceId = AUDIOMODULE_GET_INSTANCEID(moduleProperty->InstanceId);
ioTarget = AcxTargetCircuitGetWdfIoTarget(circuit->AcxTargetCircuit);
WDF_OBJECT_ATTRIBUTES_INIT(&attributes);
attributes.ParentObject = CircuitCtx->AggregatorCircuit->Circuit;
status = WdfRequestCreate(&attributes, ioTarget, &request);
if (!NT_SUCCESS(status))
{
goto exit;
}
status = AcxTargetCircuitFormatRequestForProperty(circuit->AcxTargetCircuit, request, &Params);
if (!NT_SUCCESS(status))
{
goto exit;
}
WDF_REQUEST_SEND_OPTIONS_INIT(&sendOptions, WDF_REQUEST_SEND_OPTION_SYNCHRONOUS);
WDF_REQUEST_SEND_OPTIONS_SET_TIMEOUT(&sendOptions, WDF_REL_TIMEOUT_IN_SEC(REQUEST_TIMEOUT_SECONDS));
// Whether WdfRequestSend succeeds or fails, we return the status & information, so
// there's no need to inspect the result.
WdfRequestSend(request, ioTarget, &sendOptions);
status = WdfRequestGetStatus(request);
*OutSize = WdfRequestGetInformation(request);
WdfObjectDelete(request);
goto exit;
}
}
}
ple = ple->Flink;
}
status = STATUS_SUCCESS;
exit:
return status;
}
ACX 目標通訊範例 - 釘選
此範例程式代碼示範如何使用 AcxTargetPin 來與不同堆疊公開的遠端線路針腳進行通訊。 如需 ACX Pin 的詳細資訊，請參閱 acxpin.h。
它會選取端點路徑中相同線路中最後一個磁碟區和靜音元素。
NTSTATUS FindDownstreamVolumeMute(
_In_ ACXCIRCUIT Circuit,
_In_ ACXTARGETCIRCUIT TargetCircuit
)
{
NTSTATUS status;
PDSP_CIRCUIT_CONTEXT circuitCtx;
ACX_REQUEST_PARAMETERS params;
WDF_REQUEST_SEND_OPTIONS sendOptions;
WDF_OBJECT_ATTRIBUTES attributes;
WDF_REQUEST_REUSE_PARAMS reuseParams;
circuitCtx = GetDspCircuitContext(Circuit);
//
// Note on behavior: This search algorithm will select the last Volume and Mute elements that are both
// present in the same circuit in the Endpoint Path.
// This logic could be updated to select the last Volume and Mute elements, or the first or last
// Volume or the first or last Mute element.
//
//
// First look through target's pins to determine if there's another circuit downstream.
// If there is, we'll look at that circuit for volume/mute.
//
for (ULONG pinIndex = 0; pinIndex < AcxTargetCircuitGetPinsCount(TargetCircuit); ++pinIndex)
{
ACXTARGETPIN targetPin = AcxTargetCircuitGetTargetPin(TargetCircuit, pinIndex);
ULONG targetPinFlow = 0;
ACX_REQUEST_PARAMETERS_INIT_PROPERTY(¶ms,
KSPROPSETID_Pin,
KSPROPERTY_PIN_DATAFLOW,
AcxPropertyVerbGet,
AcxItemTypePin,
AcxTargetPinGetId(targetPin),
nullptr, 0,
&targetPinFlow,
sizeof(targetPinFlow));
RETURN_NTSTATUS_IF_FAILED(SendProperty(targetPin, ¶ms, nullptr));
//
// Searching for the downstream pins. For Render, these are the dataflow out pins
//
if (circuitCtx->IsRenderCircuit && targetPinFlow != KSPIN_DATAFLOW_OUT)
{
continue;
}
else if (!circuitCtx->IsRenderCircuit && targetPinFlow != KSPIN_DATAFLOW_IN)
{
continue;
}
// Get the target pin's physical connection. We'll do this twice: first to get size and allocate, second to get the connection
PKSPIN_PHYSICALCONNECTION pinConnection = nullptr;
auto connection_free = scope_exit([&pinConnection]()
{
if (pinConnection)
{
ExFreePool(pinConnection);
pinConnection = nullptr;
}
});
ULONG pinConnectionSize = 0;
ULONG_PTR info = 0;
for (ULONG i = 0; i < 2; ++i)
{
ACX_REQUEST_PARAMETERS_INIT_PROPERTY(¶ms,
KSPROPSETID_Pin,
KSPROPERTY_PIN_PHYSICALCONNECTION,
AcxPropertyVerbGet,
AcxItemTypePin,
AcxTargetPinGetId(targetPin),
nullptr, 0,
pinConnection,
pinConnectionSize);
status = SendProperty(targetPin, ¶ms, &info);
if (status == STATUS_BUFFER_OVERFLOW)
{
// Pin connection already allocated, so how did this fail?
RETURN_NTSTATUS_IF_TRUE(pinConnection != nullptr, status);
pinConnectionSize = (ULONG)info;
pinConnection = (PKSPIN_PHYSICALCONNECTION)ExAllocatePool2(POOL_FLAG_NON_PAGED, pinConnectionSize, DRIVER_TAG);
// RETURN_NTSTATUS_IF_NULL_ALLOC causes compile errors
RETURN_NTSTATUS_IF_TRUE(pinConnection == nullptr, STATUS_INSUFFICIENT_RESOURCES);
}
else if (!NT_SUCCESS(status))
{
// There are no more connected circuits. Continue with processing this circuit.
break;
}
}
if (!NT_SUCCESS(status))
{
// There are no more connected circuits. Continue handling this circuit.
break;
}
ACXTARGETCIRCUIT nextTargetCircuit;
RETURN_NTSTATUS_IF_FAILED(CreateTargetCircuit(Circuit, pinConnection, pinConnectionSize, &nextTargetCircuit));
auto circuit_free = scope_exit([&nextTargetCircuit]()
{
if (nextTargetCircuit)
{
WdfObjectDelete(nextTargetCircuit);
nextTargetCircuit = nullptr;
}
});
RETURN_NTSTATUS_IF_FAILED_UNLESS_ALLOWED(FindDownstreamVolumeMute(Circuit, nextTargetCircuit), STATUS_NOT_FOUND);
if (circuitCtx->TargetVolumeMuteCircuit == nextTargetCircuit)
{
// The nextTargetCircuit is the owner of the volume/mute target elements.
// We will delete it when the pin is disconnected.
circuit_free.release();
// We found volume/mute. Return.
return STATUS_SUCCESS;
}
// There's only one downstream pin on the current targetcircuit, and we just processed it.
break;
}
//
// Search the target circuit for a volume or mute element.
// This sample code doesn't support downstream audioengine elements.
//
for (ULONG elementIndex = 0; elementIndex < AcxTargetCircuitGetElementsCount(TargetCircuit); ++elementIndex)
{
ACXTARGETELEMENT targetElement = AcxTargetCircuitGetTargetElement(TargetCircuit, elementIndex);
GUID elementType = AcxTargetElementGetType(targetElement);
if (IsEqualGUID(elementType, KSNODETYPE_VOLUME) &&
circuitCtx->TargetVolumeHandler == nullptr)
{
// Found Volume
circuitCtx->TargetVolumeHandler = targetElement;
}
if (IsEqualGUID(elementType, KSNODETYPE_MUTE) &&
circuitCtx->TargetMuteHandler == nullptr)
{
// Found Mute
circuitCtx->TargetMuteHandler = targetElement;
}
}
if (circuitCtx->TargetVolumeHandler && circuitCtx->TargetMuteHandler)
{
circuitCtx->TargetVolumeMuteCircuit = TargetCircuit;
return STATUS_SUCCESS;
}
//
// If we only found one of volume or mute, keep searching for both
//
if (circuitCtx->TargetVolumeHandler || circuitCtx->TargetMuteHandler)
{
circuitCtx->TargetMuteHandler = circuitCtx->TargetVolumeHandler = nullptr;
}
return STATUS_NOT_FOUND;
}
ACX 目標通訊範例 - 串流
此範例程式代碼示範如何使用 AcxTargetStream 與遠端線路的數據流通訊。 如需 ACX 數據流的詳細資訊，請參閱 acxstreams.h。
NTSTATUS status;
PRENDER_DEVICE_CONTEXT devCtx;
WDF_OBJECT_ATTRIBUTES attributes;
ACXSTREAM stream;
STREAM_CONTEXT * streamCtx;
ACXELEMENT elements[2] = {0};
ACX_ELEMENT_CONFIG elementCfg;
ELEMENT_CONTEXT * elementCtx;
ACX_STREAM_CALLBACKS streamCallbacks;
ACX_RT_STREAM_CALLBACKS rtCallbacks;
CRenderStreamEngine * streamEngine = NULL;
PAGED_CODE();
UNREFERENCED_PARAMETER(Pin);
UNREFERENCED_PARAMETER(SignalProcessingMode);
UNREFERENCED_PARAMETER(VarArguments);
// This unit-test added support for RAW and DEFAULT.
ASSERT(IsEqualGUID(*SignalProcessingMode, AUDIO_SIGNALPROCESSINGMODE_RAW) ||
IsEqualGUID(*SignalProcessingMode, AUDIO_SIGNALPROCESSINGMODE_DEFAULT));
devCtx = GetRenderDeviceContext(Device);
ASSERT(devCtx != NULL);
//
// Init streaming callbacks.
//
ACX_STREAM_CALLBACKS_INIT(&streamCallbacks);
streamCallbacks.EvtAcxStreamPrepareHardware = EvtStreamPrepareHardware;
streamCallbacks.EvtAcxStreamReleaseHardware = EvtStreamReleaseHardware;
streamCallbacks.EvtAcxStreamRun = EvtStreamRun;
streamCallbacks.EvtAcxStreamPause = EvtStreamPause;
streamCallbacks.EvtAcxStreamAssignDrmContentId = EvtStreamAssignDrmContentId;
status = AcxStreamInitAssignAcxStreamCallbacks(StreamInit, &streamCallbacks);
if (!NT_SUCCESS(status))
{
ASSERT(FALSE);
goto exit;
}
//
// Init RT streaming callbacks.
//
ACX_RT_STREAM_CALLBACKS_INIT(&rtCallbacks);
rtCallbacks.EvtAcxStreamGetHwLatency = EvtStreamGetHwLatency;
rtCallbacks.EvtAcxStreamAllocateRtPackets = EvtStreamAllocateRtPackets;
rtCallbacks.EvtAcxStreamFreeRtPackets = EvtStreamFreeRtPackets;
rtCallbacks.EvtAcxStreamSetRenderPacket = R_EvtStreamSetRenderPacket;
rtCallbacks.EvtAcxStreamGetCurrentPacket = EvtStreamGetCurrentPacket;
rtCallbacks.EvtAcxStreamGetPresentationPosition = EvtStreamGetPresentationPosition;
status = AcxStreamInitAssignAcxRtStreamCallbacks(StreamInit, &rtCallbacks);
if (!NT_SUCCESS(status))
{
ASSERT(FALSE);
goto exit;
}
//
// Create the stream.
//
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&attributes, STREAM_CONTEXT);
attributes.EvtCleanupCallback = EvtStreamCleanup;
attributes.EvtDestroyCallback = EvtStreamDestroy;
status = AcxRtStreamCreate(Device, Circuit, &attributes, &StreamInit, &stream);
if (!NT_SUCCESS(status))
{
ASSERT(FALSE);
goto exit;
}
// START-TESTING: inverted create-stream sequence.
{
ACXSTREAMBRIDGE bridge = NULL;
ACXPIN bridgePin = NULL;
ACXTARGETSTREAM targetStream = NULL;
ACX_STREAM_BRIDGE_CONFIG bridgeCfg;
ACX_STREAM_BRIDGE_CONFIG_INIT(&bridgeCfg);
bridgeCfg.InModesCount = 0; // no in-modes. this stream-bridge is manually managed.
bridgeCfg.InModes = NULL;
bridgeCfg.OutMode = NULL; // no mode, i.e., default (1st) and raw (2nd).
bridgeCfg.Flags |= AcxStreamBridgeInvertChangeStateSequence;
WDF_OBJECT_ATTRIBUTES_INIT(&attributes);
attributes.ParentObject = WdfGetDriver(); // bridge is deleted by driver obj in case of error.
status = AcxStreamBridgeCreate(Circuit, &attributes, &bridgeCfg, &bridge);
if (!NT_SUCCESS(status))
{
ASSERT(FALSE);
goto exit;
}
...
status = AcxStreamBridgeAddStream(bridge, stream);
if (!NT_SUCCESS(status))
{
ASSERT(FALSE);
goto exit;
}
// Get the Target Stream
targetStream = AcxStreamBridgeGetTargetStream(bridge, stream);
if (targetStream == NULL)
{
ASSERT(FALSE);
goto exit;
}
ACX 目標通訊範例 - 元素
此範例程式代碼示範如何使用 AcxTargetElement 與線路的 元素通訊。 如需 ACX 目標的詳細資訊，請參閱 acxtargets.h。
_In_ ACXCIRCUIT Circuit,
_In_ ACXTARGETCIRCUIT TargetCircuit
...
//
// Search the target circuit for a volume or mute element.
// This sample code doesn't support downstream audioengine elements.
//
for (ULONG elementIndex = 0; elementIndex < AcxTargetCircuitGetElementsCount(TargetCircuit); ++elementIndex)
{
ACXTARGETELEMENT targetElement = AcxTargetCircuitGetTargetElement(TargetCircuit, elementIndex);
GUID elementType = AcxTargetElementGetType(targetElement);
if (IsEqualGUID(elementType, KSNODETYPE_VOLUME) &&
circuitCtx->TargetVolumeHandler == nullptr)
{
// Found Volume
circuitCtx->TargetVolumeHandler = targetElement;
}
if (IsEqualGUID(elementType, KSNODETYPE_MUTE) &&
circuitCtx->TargetMuteHandler == nullptr)
{
// Found Mute
circuitCtx->TargetMuteHandler = targetElement;
}
}