Specialization of Serial SPI driver for CC32xx devices. More...

#include <CC32xxSPI.hxx>

Inheritance diagram for CC32xxSPI:

Public Member Functions
	CC32xxSPI (const char name, unsigned long base, uint32_t interrupt, ChipSelectMethod cs_assert, ChipSelectMethod cs_deassert, OSMutex bus_lock=nullptr, size_t dma_threshold=DEFAULT_DMA_THRESHOLD_BYTES, uint32_t dma_channel_index_tx=UDMA_CH7_GSPI_TX, uint32_t dma_channel_index_rx=UDMA_CH6_GSPI_RX)
	Constructor.

	~CC32xxSPI ()
	Destructor.

void	interrupt_handler ()
	handle an interrupt.

OSMutex *	get_lock ()
	This method provides a reference to the Mutex used by this device driver.

Public Member Functions inherited from SPI
int	transfer_with_cs_assert (struct spi_ioc_transfer *msg)
	Method to transmit/receive the data.

int	transfer_with_cs_assert_polled (struct spi_ioc_transfer *msgs, int num=1)
	Method to transmit/receive the data.

int	transfer_messages (struct spi_ioc_transfer *msgs, int num)
	Conduct multiple message transfers with one stop at the end.

Public Member Functions inherited from Device
	Device (const char *name)
	Constructor.

virtual	~Device ()
	Destructor.

Private Member Functions
void	enable () override
	Function to enable device.

void	disable () override
	Function to disable device.

int	update_configuration () override
	Update the configuration of the bus.

int	transfer (struct spi_ioc_transfer *msg) override
	Method to transmit/receive the data.

template<typename T >
int	transfer_polled (struct spi_ioc_transfer *msg)
	Method to transmit/receive the data.

int	transfer_polled (struct spi_ioc_transfer *msg) override
	Method to transmit/receive the data.

void	config_dma (struct spi_ioc_transfer *msg)
	Configure a DMA transaction.

long	data_get_non_blocking (unsigned long *data)
	Receives a word from the specified port.

long	data_put_non_blocking (unsigned long data)
	Transmits a word on the specified port.

void	data_put (unsigned long data)
	Waits until the word is transmitted on the specified port.

void	set_configuration ()
	Set the instance local configuration.

	CC32xxSPI ()
	Default constructor.

	DISALLOW_COPY_AND_ASSIGN (CC32xxSPI)

Private Member Functions inherited from Atomic
void	lock ()

void	unlock ()

Private Attributes
UDMACC32XX_Handle	dmaHandle_
	handle to DMA reference

OSSem *	sem_
	reference to the semaphore belonging to this bus

unsigned long	base_
	base address of this device

unsigned long	clock_
	clock rate supplied to the module

unsigned long	interrupt_
	interrupt of this device

size_t	dmaThreshold_
	threshold in bytes to start using DMA

uint32_t	dmaChannelIndexTx_
	TX DMA channel index.

uint32_t	dmaChannelIndexRx_
	RX DMA channel index.

uint32_t	spiChctrl_
	instance local copy of configuration

uint32_t	spiChconf_
	instance local copy of configuration

uint32_t	spiXferlevel_
	instance local copy of configuration

Static Private Attributes
static constexpr size_t	DEFAULT_DMA_THRESHOLD_BYTES = 64

static constexpr size_t	MAX_DMA_TRANSFER_AMOUNT = 1024
	Maximum number of bytes transferred in a single DMA transaction.

static constexpr uint32_t	dmaRxConfig_ []
	This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes.

static constexpr uint32_t	dmaTxConfig_ []
	This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes.

static constexpr uint32_t	dmaNullConfig_ []
	This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes when either txBuf or rxBuf are NULL.

Additional Inherited Members
Public Types inherited from SPI
typedef void(*	ChipSelectMethod) ()
	Function point for the chip select assert and deassert methods.

Static Public Member Functions inherited from Device
static int	open (struct _reent reent, const char path, int flags, int mode)
	Open a file or device.

static int	close (struct _reent *reent, int fd)
	Close a file or device.

static int	stat (struct _reent reent, const char path, struct stat *stat)
	Get the status information of a file or device.

static int	select (int nfds, fd_set readfds, fd_set writefds, fd_set *exceptfds, long long timeout)
	POSIX select().

static void	select_clear ()
	Clears the current thread's select bits.

Static Public Member Functions inherited from FileIO
static ssize_t	read (struct _reent reent, int fd, void buf, size_t count)
	Read from a file or device.

static ssize_t	write (struct _reent reent, int fd, const void buf, size_t count)
	Write to a file or device.

static _off_t	lseek (struct _reent *reent, int fd, _off_t offset, int whence)
	Change the offset index of a file or device.

static int	fstat (struct _reent reent, int fd, struct stat stat)
	Get the status information of a file or device.

static int	ioctl (int fd, unsigned long int key, unsigned long data)
	Request and ioctl transaction.

static int	fcntl (int fd, int cmd, unsigned long data)
	Manipulate a file descriptor.

static bool	is_device (int fd)
	Test if the file descriptor belongs to a device.

Protected Member Functions inherited from SPI
	SPI (const char name, ChipSelectMethod cs_assert, ChipSelectMethod cs_deassert, OSMutex bus_lock=nullptr)
	Constructor.

	~SPI ()
	Destructor.

void	bus_lock ()
	Lock the bus shared by many chip selects.

void	bus_unlock ()
	Unlock the bus shared by many chip selects.

int	ioctl (File *file, unsigned long int key, unsigned long data) override
	Request an ioctl transaction.

Protected Member Functions inherited from Node
	Node (const char *name)
	Constructor.

virtual	~Node ()
	Destructor.

int	open (File , const char , int, int) OVERRIDE
	Open method.

int	close (File *) OVERRIDE
	Close method.

virtual int	fstat (File file, struct stat stat) override
	Get the status information of a file or device.

Protected Member Functions inherited from FileIO
	FileIO (const char *name)
	Constructor.

virtual	~FileIO ()
	Destructor.

virtual off_t	lseek (File *f, off_t offset, int whence)
	Seek method.

virtual int	fcntl (File *file, int cmd, unsigned long data)
	Manipulate a file descriptor.

virtual bool	select (File *file, int mode)
	Device select method.

Static Protected Member Functions inherited from Device
static void	select_insert (SelectInfo *info)
	Add client to list of clients needing woken.

static void	select_wakeup (SelectInfo *info)
	Wakeup the list of clients needing woken.

static void	select_wakeup_from_isr (SelectInfo info, int woken)
	Wakeup the list of clients needing woken.

Static Protected Member Functions inherited from FileIO
static int	fd_alloc (void)
	Allocate a free file descriptor.

static void	fd_free (int fd)
	Free up a file descriptor.

static File *	file_lookup (int fd)
	Looks up a reference to a File corresponding to a given file descriptor.

static int	fd_lookup (File *file)
	Looks up a file descriptor corresponding to a given File reference.

Protected Attributes inherited from SPI
ChipSelectMethod	csAssert
	function pointer to a method that asserts chip select.

ChipSelectMethod	csDeassert
	function pointer to a method that deasserts chip select.

uint32_t	speedHz
	Max default speed in Hz.

uint8_t	bitsPerWord
	number of bits per word transaction

uint8_t	mode
	one of four SPI modes

bool	lsbFirst
	transmit LSB first if true

Protected Attributes inherited from Node
OSMutex	lock_
	protects internal structures.

mode_t	mode_
	File open mode, such as O_NONBLOCK.

unsigned int	references_
	number of open references

Protected Attributes inherited from FileIO
const char *	name
	device name

Static Protected Attributes inherited from FileIO
static const unsigned int	numOpenFiles = 20

static File	files []
	File descriptor pool.

static OSMutex	mutex
	mutual exclusion for fileio

Detailed Description

Specialization of Serial SPI driver for CC32xx devices.

Definition at line 53 of file CC32xxSPI.hxx.

Constructor & Destructor Documentation

◆ CC32xxSPI()

CC32xxSPI::CC32xxSPI	(	const char *	name,
		unsigned long	base,
		uint32_t	interrupt,
		ChipSelectMethod	cs_assert,
		ChipSelectMethod	cs_deassert,
		OSMutex *	bus_lock = `nullptr`,
		size_t	dma_threshold = `DEFAULT_DMA_THRESHOLD_BYTES`,
		uint32_t	dma_channel_index_tx = `UDMA_CH7_GSPI_TX`,
		uint32_t	dma_channel_index_rx = `UDMA_CH6_GSPI_RX`
	)

Constructor.

Parameters

name	name of this device instance in the file system
base	base address of this device
interrupt	interrupt number of this device
cs_assert	function pointer to a method that asserts chip select
cs_deassert	function pointer to a method that deasserts chip select
bus_lock	the user must provide a shared mutex if the device instance represents more than one chip select on the same bus interface.
dma_threshold	the threshold in bytes to use a DMA transaction, 0 = DMA always disabled
dma_channel_index_tx	UDMA_CH7_GSPI_TX or UDMA_CH31_GSPI_TX
dma_channel_index_rx	UDMA_CH6_GSPI_RX or UDMA_CH30_GSPI_RX
name	name of this device instance in the file system
base	base address of this device
interrupt	interrupt number of this device
cs_assert	function pointer to a method that asserts chip select
cs_deassert	function pointer to a method that deasserts chip select
bus_lock	the user must provide a shared mutex if the device instance represents more than one chip select on the same bus interface.

Definition at line 72 of file CC32xxSPI.cxx.

◆ ~CC32xxSPI()

CC32xxSPI::~CC32xxSPI ( )

inline

Destructor.

Definition at line 80 of file CC32xxSPI.hxx.

Member Function Documentation

◆ config_dma()

void CC32xxSPI::config_dma ( struct spi_ioc_transfer * msg )

private

Configure a DMA transaction.

Parameters

msg	message to transact.

Todo:: We could potentially perform the first daata write immediately and only use DMA for n-1 words of TX. This would reduce the latency of the transaction slightly.

Todo:: support longer SPI transactions

Definition at line 183 of file CC32xxSPI.cxx.

◆ data_get_non_blocking()

long CC32xxSPI::data_get_non_blocking ( unsigned long * data )

inlineprivate

Receives a word from the specified port.

This function gets a SPI word from the receive FIFO for the specified port.

Parameters

data	is pointer to receive data variable.

Returns: Returns the number of elements read from the receive FIFO.

Definition at line 271 of file CC32xxSPI.hxx.

◆ data_put()

void CC32xxSPI::data_put ( unsigned long data )

inlineprivate

Waits until the word is transmitted on the specified port.

This function transmits a SPI word on the transmit FIFO for the specified port. This function waits until the space is available on transmit FIFO.

Parameters

data	is data to be transmitted.

Definition at line 304 of file CC32xxSPI.hxx.

◆ data_put_non_blocking()

long CC32xxSPI::data_put_non_blocking ( unsigned long data )

inlineprivate

Transmits a word on the specified port.

This function transmits a SPI word on the transmit FIFO for the specified port.

Parameters

data	is data to be transmitted.

Returns: Returns the number of elements written to the transmit FIFO.

Definition at line 288 of file CC32xxSPI.hxx.

◆ disable()

void CC32xxSPI::disable ( )

inlineoverrideprivatevirtual

Function to disable device.

Implements Node.

Definition at line 151 of file CC32xxSPI.hxx.

◆ enable()

void CC32xxSPI::enable ( )

inlineoverrideprivatevirtual

Function to enable device.

Implements Node.

Definition at line 144 of file CC32xxSPI.hxx.

◆ get_lock()

OSMutex * CC32xxSPI::get_lock ( )

inline

This method provides a reference to the Mutex used by this device driver.

It can be passed into another SPI driver instance as a bus wide lock such that a SPI bus can be shared between this driver and another use case with another chip select.

Returns: a reference to this device driver instance lock

Definition at line 95 of file CC32xxSPI.hxx.

◆ interrupt_handler()

void CC32xxSPI::interrupt_handler ( )

handle an interrupt.

Common interrupt handler for all SPI devices.

Todo:: (Stuart Baker) this should be made private

Definition at line 292 of file CC32xxSPI.cxx.

◆ set_configuration()

void CC32xxSPI::set_configuration ( )

inlineprivate

Set the instance local configuration.

Definition at line 313 of file CC32xxSPI.hxx.

◆ transfer()

int CC32xxSPI::transfer ( struct spi_ioc_transfer * msg )

inlineoverrideprivatevirtual

Method to transmit/receive the data.

Parameters

msg	message to transact.

Implements SPI.

Definition at line 165 of file CC32xxSPI.hxx.

◆ transfer_polled() [1/2]

template<typename T >

int CC32xxSPI::transfer_polled ( struct spi_ioc_transfer * msg )

inlineprivatevirtual

Method to transmit/receive the data.

This is a template in order to preserve execution speed on type specific pointer math.

Parameters

msg	message to transact.

Implements SPI.

Definition at line 186 of file CC32xxSPI.hxx.

◆ transfer_polled() [2/2]

int CC32xxSPI::transfer_polled ( struct spi_ioc_transfer * msg )

inlineoverrideprivatevirtual

Method to transmit/receive the data.

Parameters

msg	message to transact.

Implements SPI.

Definition at line 243 of file CC32xxSPI.hxx.

◆ update_configuration()

int CC32xxSPI::update_configuration ( )

overrideprivatevirtual

Update the configuration of the bus.

Returns: >= 0 upon success, -errno upon failure

Implements SPI.

Definition at line 105 of file CC32xxSPI.cxx.

Member Data Documentation

◆ base_

unsigned long CC32xxSPI::base_

private

base address of this device

Definition at line 322 of file CC32xxSPI.hxx.

◆ clock_

unsigned long CC32xxSPI::clock_

private

clock rate supplied to the module

Definition at line 323 of file CC32xxSPI.hxx.

◆ DEFAULT_DMA_THRESHOLD_BYTES

constexpr size_t CC32xxSPI::DEFAULT_DMA_THRESHOLD_BYTES = 64

staticconstexprprivate

Definition at line 101 of file CC32xxSPI.hxx.

◆ dmaChannelIndexRx_

uint32_t CC32xxSPI::dmaChannelIndexRx_

private

RX DMA channel index.

Definition at line 327 of file CC32xxSPI.hxx.

◆ dmaChannelIndexTx_

uint32_t CC32xxSPI::dmaChannelIndexTx_

private

TX DMA channel index.

Definition at line 326 of file CC32xxSPI.hxx.

◆ dmaHandle_

UDMACC32XX_Handle CC32xxSPI::dmaHandle_

private

handle to DMA reference

Definition at line 320 of file CC32xxSPI.hxx.

◆ dmaNullConfig_

constexpr uint32_t CC32xxSPI::dmaNullConfig_

staticconstexprprivate

Initial value:

=
    {
        UDMA_SIZE_8  | UDMA_SRC_INC_NONE | UDMA_DST_INC_NONE | UDMA_ARB_1,
        UDMA_SIZE_16 | UDMA_SRC_INC_NONE | UDMA_DST_INC_NONE | UDMA_ARB_1,
        UDMA_SIZE_32 | UDMA_SRC_INC_NONE | UDMA_DST_INC_NONE | UDMA_ARB_1
    }

This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes when either txBuf or rxBuf are NULL.

Definition at line 135 of file CC32xxSPI.hxx.

◆ dmaRxConfig_

constexpr uint32_t CC32xxSPI::dmaRxConfig_

staticconstexprprivate

Initial value:

=
    {
        UDMA_SIZE_8  | UDMA_SRC_INC_NONE | UDMA_DST_INC_8  | UDMA_ARB_1,
        UDMA_SIZE_16 | UDMA_SRC_INC_NONE | UDMA_DST_INC_16 | UDMA_ARB_1,
        UDMA_SIZE_32 | UDMA_SRC_INC_NONE | UDMA_DST_INC_32 | UDMA_ARB_1
    }

This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes.

Table for an SPI DMA RX channel.

Definition at line 111 of file CC32xxSPI.hxx.

◆ dmaThreshold_

size_t CC32xxSPI::dmaThreshold_

private

threshold in bytes to start using DMA

Definition at line 325 of file CC32xxSPI.hxx.

◆ dmaTxConfig_

constexpr uint32_t CC32xxSPI::dmaTxConfig_

staticconstexprprivate

Initial value:

=
    {
        UDMA_SIZE_8  | UDMA_SRC_INC_8  | UDMA_DST_INC_NONE | UDMA_ARB_1,
        UDMA_SIZE_16 | UDMA_SRC_INC_16 | UDMA_DST_INC_NONE | UDMA_ARB_1,
        UDMA_SIZE_32 | UDMA_SRC_INC_32 | UDMA_DST_INC_NONE | UDMA_ARB_1
    }

This lookup table is used to configure the DMA channels for the appropriate (8bit, 16bit or 32bit) transfer sizes.

Table for an SPI DMA TX channel

Definition at line 123 of file CC32xxSPI.hxx.

◆ interrupt_

unsigned long CC32xxSPI::interrupt_

private

interrupt of this device

Definition at line 324 of file CC32xxSPI.hxx.

◆ MAX_DMA_TRANSFER_AMOUNT

constexpr size_t CC32xxSPI::MAX_DMA_TRANSFER_AMOUNT = 1024

staticconstexprprivate

Maximum number of bytes transferred in a single DMA transaction.

Definition at line 104 of file CC32xxSPI.hxx.

◆ sem_

OSSem* CC32xxSPI::sem_

private

reference to the semaphore belonging to this bus

Definition at line 321 of file CC32xxSPI.hxx.

◆ spiChconf_

uint32_t CC32xxSPI::spiChconf_

private

instance local copy of configuration

Definition at line 329 of file CC32xxSPI.hxx.

◆ spiChctrl_

uint32_t CC32xxSPI::spiChctrl_

private

instance local copy of configuration

Definition at line 328 of file CC32xxSPI.hxx.

◆ spiXferlevel_

uint32_t CC32xxSPI::spiXferlevel_

private

instance local copy of configuration

Definition at line 330 of file CC32xxSPI.hxx.

The documentation for this class was generated from the following files:

Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ CC32xxSPI()

◆ ~CC32xxSPI()

Member Function Documentation

◆ config_dma()

◆ data_get_non_blocking()

◆ data_put()

◆ data_put_non_blocking()

◆ disable()

◆ enable()

◆ get_lock()

◆ interrupt_handler()

◆ set_configuration()

◆ transfer()

◆ transfer_polled() [1/2]

◆ transfer_polled() [2/2]

◆ update_configuration()

Member Data Documentation

◆ base_

◆ clock_

◆ DEFAULT_DMA_THRESHOLD_BYTES

◆ dmaChannelIndexRx_

◆ dmaChannelIndexTx_

◆ dmaHandle_

◆ dmaNullConfig_

◆ dmaRxConfig_

◆ dmaThreshold_

◆ dmaTxConfig_

◆ interrupt_

◆ MAX_DMA_TRANSFER_AMOUNT

◆ sem_

◆ spiChconf_

◆ spiChctrl_

◆ spiXferlevel_