Specialization of CAN driver for Tiva CAN. More...

#include <MCP2515Can.hxx>

Inheritance diagram for MCP2515Can:

Classes
class	Buffer
	CAN TX and RX buffer structure. More...

class	BufferRead
	Setup a buffer read transfer structure. More...

class	BufferWrite
	Setup a buffer read transfer structure. More...

struct	Config1
	Configuration resgister 1 structure. More...

struct	Config2
	Configuration resgister 2 structure. More...

struct	Config3
	Configuration resgister 3 structure. More...

struct	MCP2515Baud
	Baud rate table entry. More...

Public Member Functions
	MCP2515Can (const char name, void(interrupt_enable)(), void(*interrupt_disable)())
	Constructor.

	~MCP2515Can ()
	Destructor.

void	init (const char *spi_name, uint32_t freq, uint32_t baud)
	Initialize CAN device settings.

void	interrupt_handler ()
	Handle an interrupt.

OSMutex *	get_spi_bus_lock ()
	Return a mutex that can be used by another SPI driver instance sharing the same bus as its bus lock.

Public Member Functions inherited from Can
int	available ()

int	availableForWrite ()

int	read (struct can_frame *frame)
	Read a frame if there is one available.

int	write (const struct can_frame *frame)
	Send a frame if there is space available.

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

virtual	~Device ()
	Destructor.

Public Member Functions inherited from OSThread
	OSThread (const char name, int priority, size_t stack_size, void (start_routine)(void ), void *arg)
	Create a thread.

	OSThread ()
	Creates a thread via inheritance.

void	start (const char *name, int priority, size_t stack_size)
	Starts the thread.

virtual	~OSThread ()
	Default destructor.

bool	is_created ()

void	inherit ()
	Inherits the current thread.

os_thread_t	get_handle ()

void	lock_to_thread ()
	Sets the thread handle to the current calling thread's.

void	unlock_from_thread ()
	Resets the thread handle to none.

Private Types
enum	Registers { RXF0SIDH = 0 , RXF0SIDL , RXF0SEID8 , RXF0EID0 , RXF1SIDH , RXF1SIDL , RXF1SEID8 , RXF1EID0 , RXF2SIDH , RXF2SIDL , RXF2SEID8 , RXF2EID0 , BFPCTRL , TXRTSCTRL , CANSTAT , CANCTRL , RXF3SIDH = 16 , RXF3SIDL , RXF3EID8 , RXF3EID0 , RXF4SIDH , RXF4SIDL , RXF4EID8 , RXF4EID0 , RXF5SIDH , RXF5SIDL , RXF5EID8 , RXF5EID0 , TEC , RED , RXM0SIDH = 32 , RXM0SIDL , RXM0EID8 , RXM0EID0 , RXM1SIDH , RXM1SIDL , RXM1EID8 , RXM1EID0 , CNF3 , CNF2 , CNF1 , CANINTE , CANINTF , EFLG , TXB0CTRL = 48 , TXB0SIDH , TXB0SIDL , TXB0EID8 , TXB0EID0 , TXB0DLC , TXB0D0 , TXB0D1 , TXB0D2 , TXB0D3 , TXB0D4 , TXB0D5 , TXB0D6 , TXB0D7 , TXB1CTRL = 64 , TXB1SIDH , TXB1SIDL , TXB1EID8 , TXB1EID0 , TXB1DLC , TXB1D0 , TXB1D1 , TXB1D2 , TXB1D3 , TXB1D4 , TXB1D5 , TXB1D6 , TXB1D7 , TXB2CTRL = 80 , TXB2SIDH , TXB2SIDL , TXB2EID8 , TXB2EID0 , TXB2DLC , TXB2D0 , TXB2D1 , TXB2D2 , TXB2D3 , TXB2D4 , TXB2D5 , TXB2D6 , TXB2D7 , RXB0CTRL = 96 , RXB0SIDH , RXB0SIDL , RXB0EID8 , RXB0EID0 , RXB0DLC , RXB0D0 , RXB0D1 , RXB0D2 , RXB0D3 , RXB0D4 , RXB0D5 , RXB0D6 , RXB0D7 , RXB1CTRL = 112 , RXB1SIDH , RXB1SIDL , RXB1EID8 , RXB1EID0 , RXB1DLC , RXB1D0 , RXB1D1 , RXB1D2 , RXB1D3 , RXB1D4 , RXB1D5 , RXB1D6 , RXB1D7 }
	SPI registers. More...

enum	ControlFields { CLKPRE = 0x03 , CLKEN = 0x04 , OSM = 0x08 , ABAT = 0x10 , REQOP = 0xE0 }
	Fields of the control register. More...

enum	InterruptFlags { RX0I = 0x01 , RX1I = 0x02 , TX0I = 0x04 , TX1I = 0x08 , TX2I = 0x10 , ERRI = 0x20 , WAKI = 0x40 , MERR = 0x80 }
	interrupt flag masks More...

enum	ErrorFlags { EWARN = 0x01 , RXWARN = 0x02 , TXWARN = 0x04 , RXEP = 0x08 , TXEP = 0x10 , TXBO = 0x20 , RX0OVR = 0x40 , RX1OVR = 0x80 }
	interrupt flag masks More...

enum	Instructions { RESET = 0xC0 , READ = 0x03 , READ_RX_BUF = 0x90 , WRITE = 0x02 , LOAD_TX_BUF = 0x40 , STATUS = 0xA0 , RX_STATUS = 0xB0 , RTS = 0x80 , BIT_MODIFY = 0x05 }
	SPI transaction instructions. More...

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

void *	entry () override
	User entry point for the created thread.

void	enable () override
	function to enable device

void	disable () override
	function to disable device

void	tx_msg () override
	Function to try and transmit a message.

void	tx_msg_locked ()
	Function to try and transmit a message while holding a lock.

void	reset ()
	Reset the device.

uint8_t	register_read (Registers address)
	Read from a SPI register.

void	register_write (Registers address, uint8_t data)
	Write to a SPI register.

void	bit_modify (Registers address, uint8_t data, uint8_t mask)
	Bit modify to a SPI register.

void	buffer_read (BufferRead *buf)
	Read a message to into a receive buffer.

void	buffer_write (BufferWrite buf, struct can_frame can_frame)
	Write a message to a transmit buffer.

void	request_gpio_operation ()
	Request that the GPIO cache be refreshed.

	MCP2515Can ()
	Default constructor.

	DISALLOW_COPY_AND_ASSIGN (MCP2515Can)

Private Attributes
void(*	interruptEnable_ )()
	enable interrupt callback

void(*	interruptDisable_ )()
	disable interrupt callback

unsigned	state_: 4
	present bus state

unsigned	txPending_: 2
	transmission in flight

unsigned	gpoData_: 2
	local copy of the I/O expansion output data

unsigned	gpiData_: 3
	local copy of the I/O expansion input data

unsigned	ioPending_: 1
	true if an I/O update is pending

int	spiFd_
	SPI bus that accesses MCP2515.

SPI *	spi_
	pointer to a SPI object instance

OSSem	sem_
	semaphore for posting events

Static Private Attributes
static constexpr uint32_t	SPI_MAX_SPEED_HZ = 10000000
	maximum SPI clock speed in Hz

static const MCP2515Baud	BAUD_TABLE []
	baud rate settings table

Friends
class	MCP2515GPO
	Allow access to MCP2515Can from MCP2515GPO.

class	MCP2515GPI
	Allow access to MCP2515Can from MCP2515GPI.

Additional Inherited Members
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.

Static Public Member Functions inherited from OSThread
static int	getpriority (OSThread *thread)
	Return the current thread priority.

static int	get_priority (OSThread *thread)
	Return the current thread priority.

static int	get_priority_min ()
	Get the minimum thread priority.

static int	get_priority_max ()
	Get the maximum thread priority.

Static Public Attributes inherited from Can
static unsigned	numReceivedPackets_ {0}

static unsigned	numTransmittedPackets_ {0}

Protected Member Functions inherited from Can
	Can (const char *ignored)
	Constructor.

	~Can ()
	Destructor.

	Can (const char *name, size_t tx_buffer_size=config_can_tx_buffer_size(), size_t rx_buffer_size=config_can_rx_buffer_size())
	Constructor.

	~Can ()
	Destructor.

bool	has_tx_buffer_space () OVERRIDE

bool	has_rx_buffer_data () OVERRIDE

void	flush_buffers () OVERRIDE
	called after disable

ssize_t	read (File file, void buf, size_t count) OVERRIDE
	Read from a file or device.

ssize_t	write (File file, const void buf, size_t count) OVERRIDE
	Write to a file or device.

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

Protected Member Functions inherited from Atomic
void	lock ()

void	unlock ()

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

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.

	Device (const char *name)
	Constructor.

virtual	~Device ()
	Destructor.

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.

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 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 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.

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 Attributes inherited from Can
DeviceBuffer< struct can_frame > *	txBuf
	transmit buffer

DeviceBuffer< struct can_frame > *	rxBuf
	receive buffer

unsigned int	overrunCount
	overrun count

unsigned int	busOffCount
	bus-off count

unsigned int	softErrorCount
	soft error count

Protected Attributes inherited from NonBlockNode
Notifiable *	readableNotify_
	This will be notified if the device has data avilable for read.

Notifiable *	writableNotify_
	This will be notified if the device has buffer avilable for write.

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 CAN driver for Tiva CAN.

Definition at line 56 of file MCP2515Can.hxx.

Member Enumeration Documentation

◆ ControlFields

enum MCP2515Can::ControlFields

private

Fields of the control register.

Enumerator
CLKPRE	clockout pin prescaler
CLKEN	clockout pin enable
OSM	one-shot mode
ABAT	abort all pending transmissions
REQOP	request operation mode

Definition at line 239 of file MCP2515Can.hxx.

◆ ErrorFlags

enum MCP2515Can::ErrorFlags

private

interrupt flag masks

Enumerator
EWARN	set when TEC or REC is equal to or greater than 96
RXWARN	set when REC is equal to or greater than 96
TXWARN	set when TEC is equal to or greater than 96
RXEP	set when REC is equal to or greater than 128
TXEP	set when TEC is equal to or greater than 128
TXBO	set when TEC reaches 255 (bus-off)
RX0OVR	receiver buffer 0 overflow flag
RX1OVR	receiver buffer 1 overflow flag

Definition at line 262 of file MCP2515Can.hxx.

◆ Instructions

enum MCP2515Can::Instructions

private

SPI transaction instructions.

Enumerator
RESET	resets internal registers to default state
READ	read data from register at selected address
READ_RX_BUF	read a receive buffer
WRITE	write data to register at selected address
LOAD_TX_BUF	load a transmit buffer
STATUS	read status
RX_STATUS	read rx status
RTS	request to send a tramsmit buffer
BIT_MODIFY	perform a bit manipulation

Definition at line 275 of file MCP2515Can.hxx.

◆ InterruptFlags

enum MCP2515Can::InterruptFlags

private

interrupt flag masks

Enumerator
RX0I	receive buffer 0 interrupt bit
RX1I	receive buffer 1 interrupt bit
TX0I	transmit buffer 0 interrupt bit
TX1I	transmit buffer 1 interrupt bit
TX2I	transmit buffer 2 interrupt bit
ERRI	error interrupt bit
WAKI	wake-up interrupt bit
MERR	message error interrupt bit

Definition at line 249 of file MCP2515Can.hxx.

◆ Registers

enum MCP2515Can::Registers

private

SPI registers.

Enumerator
TXRTSCTRL	TX RTS I/O control.
CANSTAT	status
CANCTRL	control
TEC	transmit error counter
RED	receive error counter
CNF3	configuration register 3
CNF2	configuration register 3
CNF1	configuration register 3
CANINTE	interrupt enable
CANINTF	interrupt flags
EFLG	error flags

Definition at line 113 of file MCP2515Can.hxx.

Constructor & Destructor Documentation

◆ MCP2515Can()

MCP2515Can::MCP2515Can	(	const char *	name,
		void(*)()	interrupt_enable,
		void(*)()	interrupt_disable
	)

inline

Constructor.

Parameters

name	name of this device instance in the file system
interrupt_enable	callback to enable the interrupt
interrupt_disable	callback to disable the interrupt

Definition at line 64 of file MCP2515Can.hxx.

◆ ~MCP2515Can()

MCP2515Can::~MCP2515Can ( )

inline

Destructor.

Definition at line 83 of file MCP2515Can.hxx.

Member Function Documentation

◆ bit_modify()

void MCP2515Can::bit_modify	(	Registers	address,
		uint8_t	data,
		uint8_t	mask
	)

inlineprivate

Bit modify to a SPI register.

Parameters

address	address to modify
data	data to modify
mask	mask of data to modify

Definition at line 613 of file MCP2515Can.hxx.

◆ buffer_read()

void MCP2515Can::buffer_read ( BufferRead * buf )

inlineprivate

Read a message to into a receive buffer.

Parameters

buf	BuffeRead object to fill in

Definition at line 627 of file MCP2515Can.hxx.

◆ buffer_write()

void MCP2515Can::buffer_write	(	BufferWrite *	buf,
		struct can_frame *	can_frame
	)

inlineprivate

Write a message to a transmit buffer.

Parameters

buf	BufferWrite object to write out over SPI
can_frame	reference to a can_frame metadata structure.

Definition at line 640 of file MCP2515Can.hxx.

◆ disable()

void MCP2515Can::disable ( )

overrideprivatevirtual

function to disable device

Implements Can.

Definition at line 171 of file MCP2515Can.cxx.

◆ enable()

void MCP2515Can::enable ( )

overrideprivatevirtual

function to enable device

Implements Can.

Definition at line 150 of file MCP2515Can.cxx.

◆ entry()

void * MCP2515Can::entry ( )

overrideprivatevirtual

User entry point for the created thread.

Returns: exit status entry point to thread

Reimplemented from OSThread.

Definition at line 261 of file MCP2515Can.cxx.

◆ get_spi_bus_lock()

OSMutex * MCP2515Can::get_spi_bus_lock ( )

inline

Return a mutex that can be used by another SPI driver instance sharing the same bus as its bus lock.

Returns: a reference to a mutex that can be used as a bus lock

Definition at line 103 of file MCP2515Can.hxx.

◆ init()

void MCP2515Can::init	(	const char *	spi_name,
		uint32_t	freq,
		uint32_t	baud
	)

Initialize CAN device settings.

Typically called in hw_postinit(), not hw_preinit() or hw_init().

Parameters

spi_name	spi interface that the MCP2515Can is on
freq	frequency in Hz that the MCP2515 clock runs at
baud	target baud rate in Hz

Definition at line 88 of file MCP2515Can.cxx.

◆ interrupt_handler()

void MCP2515Can::interrupt_handler ( )

Handle an interrupt.

Called by user provided interrupt handler.

Definition at line 464 of file MCP2515Can.cxx.

◆ ioctl()

int MCP2515Can::ioctl	(	File *	file,
		unsigned long int	key,
		unsigned long	data
	)

overrideprivatevirtual

Request an ioctl transaction.

Parameters

file	file reference for this device
key	ioctl key
data	key data

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

Reimplemented from FileIO.

Definition at line 247 of file MCP2515Can.cxx.

◆ register_read()

uint8_t MCP2515Can::register_read ( Registers address )

inlineprivate

Read from a SPI register.

Parameters

address address to read from

Returns: data read

Definition at line 577 of file MCP2515Can.hxx.

◆ register_write()

void MCP2515Can::register_write	(	Registers	address,
		uint8_t	data
	)

inlineprivate

Write to a SPI register.

Parameters

address	address to write to
data	data to write

Definition at line 596 of file MCP2515Can.hxx.

◆ request_gpio_operation()

void MCP2515Can::request_gpio_operation ( )

inlineprivate

Request that the GPIO cache be refreshed.

Definition at line 651 of file MCP2515Can.hxx.

◆ reset()

void MCP2515Can::reset ( )

inlineprivate

Reset the device.

Definition at line 560 of file MCP2515Can.hxx.

◆ tx_msg()

void MCP2515Can::tx_msg ( )

inlineoverrideprivatevirtual

Function to try and transmit a message.

Implements Can.

Definition at line 541 of file MCP2515Can.hxx.

◆ tx_msg_locked()

void MCP2515Can::tx_msg_locked ( )

private

Function to try and transmit a message while holding a lock.

Definition at line 191 of file MCP2515Can.cxx.

Friends And Related Symbol Documentation

◆ MCP2515GPI

friend class MCP2515GPI

friend

Allow access to MCP2515Can from MCP2515GPI.

Definition at line 685 of file MCP2515Can.hxx.

◆ MCP2515GPO

friend class MCP2515GPO

friend

Allow access to MCP2515Can from MCP2515GPO.

Definition at line 682 of file MCP2515Can.hxx.

Member Data Documentation

◆ BAUD_TABLE

const MCP2515Can::MCP2515Baud MCP2515Can::BAUD_TABLE

staticprivate

Initial value:

=
{
    
    {20000000, 125000, {(5 - 1), (3 - 1)},
                       {(7 - 1), (4 - 1), 0, 1},
                       {(4 - 1), 0, 0}},
    
    {8000000, 125000, {(2 - 1), (3 - 1)},
                      {(7 - 1), (4 - 1), 0, 1},
                      {(4 - 1), 0, 0}}
}

baud rate settings table

Definition at line 41 of file MCP2515Can.hxx.

◆ gpiData_

unsigned MCP2515Can::gpiData_

private

local copy of the I/O expansion input data

Definition at line 665 of file MCP2515Can.hxx.

◆ gpoData_

unsigned MCP2515Can::gpoData_

private

local copy of the I/O expansion output data

Definition at line 664 of file MCP2515Can.hxx.

◆ interruptDisable_

void(* MCP2515Can::interruptDisable_) ()

private

disable interrupt callback

Definition at line 661 of file MCP2515Can.hxx.

◆ interruptEnable_

void(* MCP2515Can::interruptEnable_) ()

private

enable interrupt callback

Definition at line 660 of file MCP2515Can.hxx.

◆ ioPending_

unsigned MCP2515Can::ioPending_

private

true if an I/O update is pending

Definition at line 666 of file MCP2515Can.hxx.

◆ sem_

OSSem MCP2515Can::sem_

private

semaphore for posting events

Definition at line 669 of file MCP2515Can.hxx.

◆ spi_

SPI* MCP2515Can::spi_

private

pointer to a SPI object instance

Definition at line 668 of file MCP2515Can.hxx.

◆ SPI_MAX_SPEED_HZ

constexpr uint32_t MCP2515Can::SPI_MAX_SPEED_HZ = 10000000

staticconstexprprivate

maximum SPI clock speed in Hz

Definition at line 110 of file MCP2515Can.hxx.

◆ spiFd_

int MCP2515Can::spiFd_

private

SPI bus that accesses MCP2515.

Definition at line 667 of file MCP2515Can.hxx.

◆ state_

unsigned MCP2515Can::state_

private

present bus state

Definition at line 662 of file MCP2515Can.hxx.

◆ txPending_

unsigned MCP2515Can::txPending_

private

transmission in flight

Definition at line 663 of file MCP2515Can.hxx.

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

Classes

Public Member Functions

Private Types

Private Member Functions

Private Attributes

Static Private Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ ControlFields

◆ ErrorFlags

◆ Instructions

◆ InterruptFlags

◆ Registers

Constructor & Destructor Documentation

◆ MCP2515Can()

◆ ~MCP2515Can()

Member Function Documentation

◆ bit_modify()

◆ buffer_read()

◆ buffer_write()

◆ disable()

◆ enable()

◆ entry()

◆ get_spi_bus_lock()

◆ init()

◆ interrupt_handler()

◆ ioctl()

◆ register_read()

◆ register_write()

◆ request_gpio_operation()

◆ reset()

◆ tx_msg()

◆ tx_msg_locked()

Friends And Related Symbol Documentation

◆ MCP2515GPI

◆ MCP2515GPO

Member Data Documentation

◆ BAUD_TABLE

◆ gpiData_

◆ gpoData_

◆ interruptDisable_

◆ interruptEnable_

◆ ioPending_

◆ sem_

◆ spi_

◆ SPI_MAX_SPEED_HZ

◆ spiFd_

◆ state_

◆ txPending_