CMMFHwDevice Class Reference

#include <mmf/server/mmfhwdevice.h>

Link against: tsu_mdf_omxvorbiscodecs.lib

class CMMFHwDevice : public CBase

Inherits from

CMMFHwDevice

Protected Attributes
MMMFHwDeviceObserver *	iHwDeviceObserver

Public Member Functions
virtual	~CMMFHwDevice()
pure virtual TAny *	CustomInterface(TUid)
pure virtual TInt	DeleteCodec()
pure virtual TInt	Init(THwDeviceInitParams &)
CMMFHwDevice *	NewL(const TFourCC &, const TFourCC &)
CMMFHwDevice *	NewL(const TFourCC &, const TFourCC &, const TDesC &)
CMMFHwDevice *	NewL(TUid)
CMMFHwDevice *	NewL(TFileName)
pure virtual TInt	Pause()
pure virtual TInt	SetConfig(TTaskConfig &)
pure virtual TInt	Start(TDeviceFunc, TDeviceFlow)
pure virtual TInt	Stop()
pure virtual TInt	StopAndDeleteCodec()
pure virtual TInt	ThisHwBufferEmptied(CMMFBuffer &)
pure virtual TInt	ThisHwBufferFilled(CMMFBuffer &)

Inherited Functions
	CBase::CBase()
	CBase::Delete(CBase *)
	CBase::Extension_(TUint,TAny &,TAny )
	CBase::operator new(TUint)
	CBase::operator new(TUint,TAny *)
	CBase::operator new(TUint,TLeave)
	CBase::operator new(TUint,TLeave,TUint)
	CBase::operator new(TUint,TUint)
	CBase::~CBase()

Detailed Description

ECom plugin class for a hardware device that decodes (plays) source data in a certain FourCC coding type to another FourCC coding type or encodes (records) data from a certain FourCC coding type to a another FourCC coding type.

The hardware device can be instantiated in 3 different ways:

1. NewL(const TFourCC& aSrcDatatype, const TFourCC& aDstDataType)

This instantiate a hardware device that can encode or decode the aSrcDatatype to a aDstDataType.

2. NewL(const TFourCC& aSrcDatatype, const TFourCC& aDstDataType, const TDesC& aPreferredSupplier)

This is similar to the above but is used where there may be multiple hardware devices that perform the same conversion. Third party developers may use their own hardware device implementations and can ensure the controller uses their implementation by setting the preferred supplier to themselves.

3. NewL(TUid aUid)

This is used to explicitly instantiate a hardware device where the UID is known.

4. NewL(TFileName aFileName)

This is used to create an instance of a HwDevice implementation by loading the library

CMMFHwDevice provides a generic interface that every Hardware Device that decodes and/or encodes has to implement. Based on parameters specified in Start, the device implementation will start decoding or encoding. The source and destination of the decoding/encoding operations should be set up before starting the task by sending THwDeviceInitParams to the Init() function.

Member Attribute Documentation

iHwDeviceObserver

MMMFHwDeviceObserver *

iHwDeviceObserver

[protected]

A pointer to the hardware device observer.

Constructor & Destructor Documentation

~CMMFHwDevice ( )

~CMMFHwDevice

(

)

[inline, virtual]

Destructor.

The destructor is called by ECom framework allowing derived classes to clean up the implementation specific resources.

Destructor

Member Function Documentation

CustomInterface ( TUid )

TAny *

CustomInterface

(

TUid

aInterfaceId

)

[pure virtual]

Retrieves a custom interface to the device.

Parameter	Description
aInterfaceId	The interface UID, defined with the custom interface.

Returns: A pointer to the interface implementation, or NULL if the device does not implement the interface requested. The return value must be cast to the correct type by the user.

DeleteCodec ( )

TInt

DeleteCodec

(

)

[pure virtual]

Call this function to delete a codec.

This is used to allow resources to be freed when using a DSP or similar hardware.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

Init ( THwDeviceInitParams & )

TInt

Init

(

THwDeviceInitParams &

aDevInfo

)

[pure virtual]

Initializes the hardware device tasks.

Parameter	Description
aDevInfo	The device initialization parameters.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

NewL ( const TFourCC &, const TFourCC & )

CMMFHwDevice *	NewL	(	const TFourCC &	aSrcDatatype,
			const TFourCC &	aDstDataType
		)	[static]

NewL ( const TFourCC &, const TFourCC &, const TDesC & )

CMMFHwDevice *	NewL	(	const TFourCC &	aSrcDatatype,
			const TFourCC &	aDstDataType,
			const TDesC &	aPreferredSupplier
		)	[static]

NewL ( TUid )

CMMFHwDevice *

NewL

(

TUid

aUid

)

[static, inline]

Create a CMMFHwDevice object with a known implementation Uid. Will leave if it is not found (KErrNotFound).

Parameter	Description
aUid	- The Uid of a plugin implementation

Returns: An instantiated CMMFHwDevice derived object from ECom.

NewL ( TFileName )

CMMFHwDevice *

NewL

(

TFileName

aFileName

)

[static, inline]

Create a CMMFHwDevice object from .dll. Will leave if dll cannot be loaded (KErrNotFound).

Parameter	Description
aFileName	Implementation .dll

Returns: an instantiated CMMFHwDevice derived object from a DLL.

Pause ( )

TInt

Pause

(

)

[pure virtual]

Temporarily suspends the current task of decoding or encoding.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

SetConfig ( TTaskConfig & )

TInt

SetConfig

(

TTaskConfig &

aConfig

)

[pure virtual]

Used to configure the sample rate and stereo mode of a CMMFHwDevice plugin.

The configuration of HwDevices is device specific and is not used in any of the reference devices that return KErrNotSupported.

Parameter	Description
aConfig	The device configuration.

Start ( TDeviceFunc, TDeviceFlow )

TInt	Start	(	TDeviceFunc	aFuncCmd,
			TDeviceFlow	aFlowCmd
		)	[pure virtual]

Starts Encoding or Decoding task(s) based on the parameter specified.

Parameter	Description
aFuncCmd	The device function specifying the requested service i.e. decode or encode.
aFlowCmd	The device flow directions for the requested service.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

Stop ( )

TInt

Stop

(

)

[pure virtual]

Stops the current on-going task.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

StopAndDeleteCodec ( )

TInt

StopAndDeleteCodec

(

)

[pure virtual]

Call this function to stop and then delete a codec. This is used to allow resources to be freed when using a DSP or similar hardware.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

ThisHwBufferEmptied ( CMMFBuffer & )

TInt

ThisHwBufferEmptied

(

CMMFBuffer &

aEmptyBufferPtr

)

[pure virtual]

Call this function to notify hardware device implementation that data in aEmptyBufferPtr from encoding is processed.

Parameter	Description
aEmptyBufferPtr	The data buffer processed by the observer.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.

ThisHwBufferFilled ( CMMFBuffer & )

TInt

ThisHwBufferFilled

(

CMMFBuffer &

aFillBufferPtr

)

[pure virtual]

Call this function to notify hardware device implementation that data is available in aFillBufferPtr for decoding.

Parameter	Description
aFillBufferPtr	The data buffer filled by the observer.

Returns: An error code indicating if the function call was successful. KErrNone on success, otherwise another of the system-wide error codes.