Instances of this class handle access to a MultiMedia Card via the MityDSP SPI interface. More...

#include <core/DspMmc.h>

Inheritance diagram for MityDSP::tcDspMmc:

Classes
union	tuMmcStatus
	status information returned by MMC card More...

Public Member Functions
	tcDspMmc (tcDspSpi apSpi, tcDspOutputLatch apLatch, unsigned int anLatchID, LCK_Handle ahLock=NULL)
	This constructor is used to open an interface to a MMC device via the provided SPI interface.
	~tcDspMmc ()
	Default destructor.
virtual bool	reinit (void)
	This method reinitializes the MMC device, places it in on-line mode, and queries the device for its Chip-Specific Data.
virtual int	write (void apAddr, void apData, int anBytes)
	This routine writes an arbitrary amount of data to an MMC device at a specified offset from the start of the device.
virtual int	write (unsigned int anSector, unsigned int anOffset, void *apData, int anBytes)
	Sector-based version of the write method.
virtual int	read (void apStartAddr, void apBuffer, int anBytes)
	This routine reads an arbitrary amount of data from an MMC device from the specified offset position.
virtual int	read (unsigned int anSector, unsigned int anOffset, void *apBuffer, int anBytes)
	Sector-based version of the read method.
virtual void	setCardDetectGPIO (tcDspGpio *aGpio, int anThreadPri)
	Sets the GPIO used for card detect.
virtual void	cardDetectInterrupt (void)
	Interrupt service routine for the MMC class.
virtual tuMmcStatus	get_status (void)
	This method reads the MMC card Status register and returns its contents.
virtual const char *	get_info (void)
	This method reads the MMC card CID register, decodes the information, and returns a summary information string.
Public Member Functions inherited from MityDSP::tcDspStorageBase
	tcDspStorageBase ()
	This constructor is used to initialize storage base class.
virtual	~tcDspStorageBase ()
	Default Destructor.
virtual bool	erase (unsigned int anSector)
	This routine provides a default erase method.
virtual void	registerISRCallback (tfIsrCallback afCallback, void *apUserArg)
	This method is used to register a callback that is activated whenever the device changes state.
virtual void *	getAddress (unsigned int anSector, unsigned int anOffset)
	This routine uses the device's sector map to compute an offset address from a supplied sector and offset.
virtual unsigned int	getSize (unsigned int anSector)
	This routine uses the device's sector map to determine the size of the specified sector.
virtual unsigned int	getSector (void *apAddr)
	This routine uses the device's sector map to compute a sector from a from a supplied offset address.
virtual double	getDeviceSizeKB (void)
	This routine returns the size of the device in kilobytes.
const tsSectorMap *	getMap (int &anNumSectors)
	This routine returns a pointer to access the device's sector map.
virtual bool	getMediaPresent ()

Static Public Member Functions
static void	interrupt_dispatch (tcDspGpio aGpio, unsigned int mask, void aMmc)
	Static interrupt dispatch routine.
static void	cardDetectDispatch (Arg mmcCard)
	Static thread dispatch routine.
Static Public Member Functions inherited from MityDSP::tcDspStorageBase
static int	readDispatch (unsigned int anSector, unsigned int anOffset, char apBuffer, unsigned int anLength, void apInstance)
	Static dispatch routine to allow the read method to be registered as a callback.
static int	writeDispatch (unsigned int anSector, unsigned int anOffset, char apData, unsigned int anBytes, void apInstance)
	Static dispatch routine to allow the write method to be registered as a callback.

Static Public Attributes
static const int	gnSTAT_LENGTH = 2
	length (in bytes) of status info
static const int	gnBLOCK_SIZE = 512
	fixed block size for high capacity SD cards;

Protected Member Functions
virtual void	cardDetectThread ()
	Thread to pend on the card detect semaphore.
bool	initialize (void)
	This method resets the MMC device, places it in on-line mode, and queries the device for its Chip-Specific Data.
bool	read_sector (unsigned int anSector)
	This method reads the specified sector of the MMC device into the page buffer.
bool	write_sector (unsigned int anSector)
	This method writes the page buffer out to the specified sector of the MMC device.
bool	check_write (void)
	This method checks to see if a previous write operation was successful.
void	setup_spi (void)
	This method is used to set the SPI in the required mode for the MMC interface.
bool	wait_for_response (unsigned char anExpected, int anAttempts=256, int *apRequired=NULL)
	This method reads the SPI interface repeatedly, waiting for a specified response.

Protected Attributes
LCK_Handle	mhMutex
	Lock to serialize access.
tcDspSpi *	mpSpi
	Access to the SPI bus.
tcDspOutputLatch *	mpLatch
	Access to latch selector.
unsigned int	mnLatchID
	ID of latch to use (if any)
unsigned int	mnSectorSize
	Sector size (bytes)
bool	mbIsHighCapacity
	if true, a high capacity SD card
bool	mbMutexCreated
	True if mutex created locally.
unsigned char *	mpPageBuffer
	Buffer for a sector of data.
tcDspGpio *	mpGpio
	GPIO for card detect interrupt.
unsigned short	mnMyIntMask
	core interrupt mask.
int	mnMyIntLevel
	core interrupt level.
int	mnMyIntVector
	core interrupt vector.
SEM_Handle	mhCardDetectSem
	Semaphore for card detect.
TSK_Handle	mhCardDetectThrd
	Thread used for card detect "debounce".
Protected Attributes inherited from MityDSP::tcDspStorageBase
unsigned int	mnNumSectors
	Number of sectors in this device.
double	mnDeviceSize
	Overall device size (in bytes)
tsSectorMap *	mpSectorInfo
	Map of sectors and sizes.
bool	mbMediaPresent
	True if device is loaded.
tfIsrCallback	mfIsrCallback
void *	mpUserArg
	User-supplied argument for ISR callback.

Additional Inherited Members
Public Types inherited from MityDSP::tcDspStorageBase
typedef void(*	tfIsrCallback )(bool, void *)
	prototype for the ISR callback
Public Attributes inherited from MityDSP::tcDspStorageBase
unsigned int	mnTxBytes
	Count of bytes written (debug)
unsigned int	mnRxBytes
	Count of bytes read (debug)

Detailed Description

Instances of this class handle access to a MultiMedia Card via the MityDSP SPI interface.

It is derived from tcDspStorageBase to provide a consistent interface for higher-level drivers (such as filesystems).

See also:: tcDspMmc Page

Constructor & Destructor Documentation

tcDspMmc::tcDspMmc	(	tcDspSpi *	apSpi,
		tcDspOutputLatch *	apLatch,
		unsigned int	anLatchID,
		LCK_Handle	ahLock = `NULL`
	)

This constructor is used to open an interface to a MMC device via the provided SPI interface.

Parameters:

[in]	apSpi	Pointer to the SPI interface for the MMC.
[in]	apLatch	Pointer to an output latch controlling Chip Select.
[in]	anLatchID	ID of the latch to use for this device.
[in]	ahLock	Optional parameter specifying a lock to use to protect MMC (and SPI) writes.

Note:: Specifying a shared lock to all devices sharing a SPI bus allows them to operate simultaneously. Not necessary if the SPI is used exclusively for the MMC device.

Returns:: None.

See also:: DspMmc.h

tcDspMmc::~tcDspMmc ( )

Default destructor.

Returns:: None.

See also:: DspMmc.h

Member Function Documentation

void tcDspMmc::interrupt_dispatch	(	tcDspGpio *	aGpio,
		unsigned int	aMask,
		void *	aMmc
	)

static

Static interrupt dispatch routine.

Required because of the hidden this pointer associated with a member function, which cannot be passed directly to the interrupt dispatcher.

Parameters:

[in]	aGpio	The GPIO pointer
[in]	aMask	The GPIO bit that triggered the interrupt
[in]	aMmc	The tcDspMmc pointer

Returns:: 0

void tcDspMmc::cardDetectDispatch ( Arg mmcCard )

static

Static thread dispatch routine.

Required because of the hidden this pointer associated with a member function, which cannot be passed directly to the thread.

Parameters:

[in] mmcCard The "this->" pointer for the instance of tcDspMmc associated with this thread.

Returns:: 0

bool tcDspMmc::reinit ( void )

virtual

This method reinitializes the MMC device, places it in on-line mode, and queries the device for its Chip-Specific Data.

If the sector size, the number of sectors available, or the overall device size changes, the sector map and page buffer are recreated.

Returns:: True if reinitialization was successful.

See also:: DspMmc.h

int tcDspMmc::write	(	void *	apAddr,
		void *	apData,
		int	anBytes
	)

virtual

This routine writes an arbitrary amount of data to an MMC device at a specified offset from the start of the device.

The routine handles preservation of data when only a partial sector is written. The data does not have to be sector aligned, although writing aligned, full sectors is most efficient.

Parameters:

[in]	apAddr	Pointer to the offset position on the MMC device.
[in]	apData	A buffer containing the data to be written.
[in]	anBytes	Size of the data to be written in bytes.

Returns:: The number of bytes successfully written.

See also:: DspMmc.h

Implements MityDSP::tcDspStorageBase.

int tcDspMmc::write	(	unsigned int	anSector,
		unsigned int	anOffset,
		void *	apData,
		int	anBytes
	)

virtual

Sector-based version of the write method.

Parameters:

[in]	anSector	The sector to write to.
[in]	anOffset	The offset from the start of the sector.
[in]	apData	A buffer containing the data to be written.
[in]	anBytes	Size of the data to be written in bytes.

Returns:: The number of bytes successfully written.

See also:: DspMmc.h

Implements MityDSP::tcDspStorageBase.

int tcDspMmc::read	(	void *	apStartAddr,
		void *	apBuffer,
		int	anBytes
	)

virtual

This routine reads an arbitrary amount of data from an MMC device from the specified offset position.

Results of the read are stored in apBuffer.

Parameters:

[in]	apStartAddr	Pointer to the data offset on the MMC device.
[out]	apBuffer	A buffer to hold the data that is read.
[in]	anBytes	Size of the data to be read in bytes.

Returns:: The number of bytes successfully read.

See also:: DspMmc.h

Implements MityDSP::tcDspStorageBase.

int tcDspMmc::read	(	unsigned int	anSector,
		unsigned int	anOffset,
		void *	apBuffer,
		int	anBytes
	)

virtual

Sector-based version of the read method.

Parameters:

[in]	anSector	The sector to copy from.
[in]	anOffset	The offset from the start of the sector.
[out]	apBuffer	A buffer to hold the data that is read.
[in]	anBytes	Size of the data to be read in bytes.

Returns:: The number of bytes successfully read.

See also:: DspMmc.h

Implements MityDSP::tcDspStorageBase.

void tcDspMmc::setCardDetectGPIO	(	tcDspGpio *	aGpio,
		int	anThreadPri
	)

virtual

Sets the GPIO used for card detect.

This function enablesd interrupts on GPIO_2 for use as a card detect.

Parameters:

[in]	aGpio	The GPIO with GPIO_2 as card detect line(NULL for none).
[in]	anThreadPri	Thread priority of the debouncer

Returns:: None.

void tcDspMmc::cardDetectInterrupt ( void )

virtual

Interrupt service routine for the MMC class.

The ISR reads and clears the pending interrupt. If the pending interrupt has a callback registered for it, the routine is called.

"Interrupt-ness" is taken care of by the 'dispatcher' in DSP/BIOS. Installed by the constructor.

tcDspMmc::tuMmcStatus tcDspMmc::get_status ( void )

virtual

This method reads the MMC card Status register and returns its contents.

Note:: The returned structure contains an mbZERO field. This field is non-zero if the status request fails.

Returns:: MMC status register contents.

See also:: DspMmc.h

const char * tcDspMmc::get_info ( void )

virtual

This method reads the MMC card CID register, decodes the information, and returns a summary information string.

Note:: The returned string is valid until the next time the info() method is called.

Returns:: Pointer to the information string (which contains "No Response" if there was a failure).

See also:: DspMmc.h

void tcDspMmc::cardDetectThread ( )

protectedvirtual

Thread to pend on the card detect semaphore.

When the semaphore is posted the thread will sleep for a tenth of a second then wake and re-enable interrupts, then call the callback if it's set.

Returns:: 0

bool tcDspMmc::initialize ( void )

protected

This method resets the MMC device, places it in on-line mode, and queries the device for its Chip-Specific Data.

This data is used to determine the sector size, the number of sectors available, and the overall device size.

Returns:: True if initialization was successful.

See also:: DspMmc.h

bool tcDspMmc::read_sector ( unsigned int anSector )

protected

This method reads the specified sector of the MMC device into the page buffer.

Parameters:

[in] anSector The sector to read into the page buffer.

Returns:: True if the sector was successfully read.

See also:: DspMmc.h

bool tcDspMmc::write_sector ( unsigned int anSector )

protected

This method writes the page buffer out to the specified sector of the MMC device.

Parameters:

[in] anSector The sector to write the page buffer to.

Returns:: True if the page buffer was successfully written.

See also:: DspMmc.h

bool tcDspMmc::check_write ( void )

protected

This method checks to see if a previous write operation was successful.

Returns:: True if successful.

See also:: DspMmc.h

void tcDspMmc::setup_spi ( void )

protected

This method is used to set the SPI in the required mode for the MMC interface.

It is called before every read and write, so that the SPI may be used with multiple devices simultaneously (in conjunction with a shared lock).

Returns:: None.

See also:: DspMmc.h

bool tcDspMmc::wait_for_response	(	unsigned char	anExpected,
		int	anAttempts = `256`,
		int *	apRequired = `NULL`
	)

protected

This method reads the SPI interface repeatedly, waiting for a specified response.

The routine returns "true" if the response is received within the specified number of attempts.

Parameters:

[in]	anExpected	The 8-bit response to wait for.
[in]	anAttempts	Number of attempts to read the expected response (default: 256).
[out]	apRequired	if passed in (default is NULL), will be set to the number of cycles required to complete the response.

Returns:: True if expected response is received, false otherwise.

See also:: DspMmc.h

Member Data Documentation

const int MityDSP::tcDspMmc::gnSTAT_LENGTH = 2

static

length (in bytes) of status info

const int MityDSP::tcDspMmc::gnBLOCK_SIZE = 512

static

fixed block size for high capacity SD cards;

LCK_Handle MityDSP::tcDspMmc::mhMutex

protected

Lock to serialize access.

tcDspSpi* MityDSP::tcDspMmc::mpSpi

protected

Access to the SPI bus.

tcDspOutputLatch* MityDSP::tcDspMmc::mpLatch

protected

Access to latch selector.

unsigned int MityDSP::tcDspMmc::mnLatchID

protected

ID of latch to use (if any)

unsigned int MityDSP::tcDspMmc::mnSectorSize

protected

Sector size (bytes)

bool MityDSP::tcDspMmc::mbIsHighCapacity

protected

if true, a high capacity SD card

bool MityDSP::tcDspMmc::mbMutexCreated

protected

True if mutex created locally.

unsigned char* MityDSP::tcDspMmc::mpPageBuffer

protected

Buffer for a sector of data.

tcDspGpio* MityDSP::tcDspMmc::mpGpio

protected

GPIO for card detect interrupt.

unsigned short MityDSP::tcDspMmc::mnMyIntMask

protected

core interrupt mask.

int MityDSP::tcDspMmc::mnMyIntLevel

protected

core interrupt level.

int MityDSP::tcDspMmc::mnMyIntVector

protected

core interrupt vector.

SEM_Handle MityDSP::tcDspMmc::mhCardDetectSem

protected

Semaphore for card detect.

TSK_Handle MityDSP::tcDspMmc::mhCardDetectThrd

protected

Thread used for card detect "debounce".

Classes

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation