I2C Slave Interface

Detailed Description

Interface for I2C slave communication.

Summary

The I2C slave interface provides a common API for I2C HAL drivers. The I2C slave interface supports:

• Interrupt driven transmit/receive processing
• Callback function support which returns a event codes

Data Structures
struct	i2c_slave_callback_args_t
struct	i2c_slave_cfg_t
struct	i2c_slave_api_t
struct	i2c_slave_instance_t

Typedefs
typedef void	i2c_slave_ctrl_t

Enumerations
enum	i2c_slave_rate_t
enum	i2c_slave_addr_mode_t
enum	i2c_slave_event_t

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Data Structure Documentation

i2c_slave_callback_args_t

struct i2c_slave_callback_args_t

I2C callback parameter definition

Data Fields
void const *	p_context	Pointer to user-provided context.
uint32_t	bytes	Number of received/transmitted bytes in buffer.
i2c_slave_event_t	event	Event code.

i2c_slave_cfg_t

struct i2c_slave_cfg_t

I2C configuration block

Data Fields
uint8_t	channel
	Identifier recognizable by implementation. More...
i2c_slave_rate_t	rate
	Device's maximum clock rate from enum i2c_rate_t.
uint16_t	slave
	The address of the slave device.
i2c_slave_addr_mode_t	addr_mode
	Indicates how slave fields should be interpreted.
bool	general_call_enable
	Allow a General call from master.
IRQn_Type	rxi_irq
	Receive IRQ number.
IRQn_Type	txi_irq
	Transmit IRQ number.
IRQn_Type	tei_irq
	Transmit end IRQ number.
IRQn_Type	eri_irq
	Error IRQ number.
uint8_t	ipl
	Interrupt priority level for receive, transmit, and transmit end interrupts.
uint8_t	eri_ipl
	Interrupt priority level for error interrupt.
bool	clock_stretching_enable
	Low Hold SCL during reception for the period between the 9th and the 1st clock cycle.
transfer_instance_t const *	p_transfer_tx
	DTC instance for I2C transmit.Set to NULL if unused. More...
transfer_instance_t const *	p_transfer_rx
	DTC instance for I2C receive. Set to NULL if unused.
void(*	p_callback )(i2c_slave_callback_args_t *p_args)
	Pointer to callback function. More...
void const *	p_context
	Pointer to the user-provided context.
void const *	p_extend
	Any configuration data needed by the hardware. More...

Field Documentation

channel

uint8_t i2c_slave_cfg_t::channel

Identifier recognizable by implementation.

Generic configuration

p_transfer_tx

transfer_instance_t const* i2c_slave_cfg_t::p_transfer_tx

DTC instance for I2C transmit.Set to NULL if unused.

DTC support

p_callback

void(* i2c_slave_cfg_t::p_callback) (i2c_slave_callback_args_t *p_args)

Pointer to callback function.

Parameters to control software behavior

p_extend

void const* i2c_slave_cfg_t::p_extend

Any configuration data needed by the hardware.

Implementation-specific configuration

i2c_slave_api_t

struct i2c_slave_api_t

Interface definition for I2C access as slave

Data Fields
fsp_err_t(*	open )(i2c_slave_ctrl_t *const p_ctrl, i2c_slave_cfg_t const *const p_cfg)
fsp_err_t(*	read )(i2c_slave_ctrl_t *const p_ctrl, uint8_t *const p_dest, uint32_t const bytes)
fsp_err_t(*	write )(i2c_slave_ctrl_t *const p_ctrl, uint8_t *const p_src, uint32_t const bytes)
fsp_err_t(*	callbackSet )(i2c_slave_ctrl_t *const p_ctrl, void(*p_callback)(i2c_slave_callback_args_t *), void const *const p_context, i2c_slave_callback_args_t *const p_callback_memory)
fsp_err_t(*	close )(i2c_slave_ctrl_t *const p_ctrl)

Field Documentation

open

fsp_err_t(* i2c_slave_api_t::open) (i2c_slave_ctrl_t *const p_ctrl, i2c_slave_cfg_t const *const p_cfg)

Opens the I2C Slave driver and initializes the hardware.

Parameters

[in]	p_ctrl	Pointer to control block. Must be declared by user. Elements are set here.
[in]	p_cfg	Pointer to configuration structure.

read

fsp_err_t(* i2c_slave_api_t::read) (i2c_slave_ctrl_t *const p_ctrl, uint8_t *const p_dest, uint32_t const bytes)

Performs a read operation on an I2C Slave device.

Parameters

[in]	p_ctrl	Pointer to control block set in i2c_slave_api_t::open call.
[in]	p_dest	Pointer to the location to store read data.
[in]	bytes	Number of bytes to read.

write

fsp_err_t(* i2c_slave_api_t::write) (i2c_slave_ctrl_t *const p_ctrl, uint8_t *const p_src, uint32_t const bytes)

Performs a write operation on an I2C Slave device.

Parameters

[in]	p_ctrl	Pointer to control block set in i2c_slave_api_t::open call.
[in]	p_src	Pointer to the location to get write data from.
[in]	bytes	Number of bytes to write.

callbackSet

fsp_err_t(* i2c_slave_api_t::callbackSet) (i2c_slave_ctrl_t *const p_ctrl, void(*p_callback)(i2c_slave_callback_args_t *), void const *const p_context, i2c_slave_callback_args_t *const p_callback_memory)

Specify callback function and optional context pointer and working memory pointer.

Parameters

[in]	p_ctrl	Pointer to the IIC Slave control block.
[in]	p_callback	Callback function
[in]	p_context	Pointer to send to callback function
[in]	p_working_memory	Pointer to volatile memory where callback structure can be allocated. Callback arguments allocated here are only valid during the callback.

close

fsp_err_t(* i2c_slave_api_t::close) (i2c_slave_ctrl_t *const p_ctrl)

Closes the driver and releases the I2C Slave device.

Parameters

[in]

p_ctrl

Pointer to control block set in i2c_slave_api_t::open call.

i2c_slave_instance_t

struct i2c_slave_instance_t

This structure encompasses everything that is needed to use an instance of this interface.

Data Fields
i2c_slave_ctrl_t *	p_ctrl	Pointer to the control structure for this instance.
i2c_slave_cfg_t const *	p_cfg	Pointer to the configuration structure for this instance.
i2c_slave_api_t const *	p_api	Pointer to the API structure for this instance.

Typedef Documentation

i2c_slave_ctrl_t

typedef void i2c_slave_ctrl_t

I2C control block. Allocate an instance specific control block to pass into the I2C API calls.

Enumeration Type Documentation

i2c_slave_rate_t

enum i2c_slave_rate_t

Communication speed options

Enumerator
I2C_SLAVE_RATE_STANDARD	100 kHz
I2C_SLAVE_RATE_FAST	400 kHz
I2C_SLAVE_RATE_FASTPLUS	1 MHz

i2c_slave_addr_mode_t

enum i2c_slave_addr_mode_t

Addressing mode options

Enumerator
I2C_SLAVE_ADDR_MODE_7BIT	Use 7-bit addressing mode.
I2C_SLAVE_ADDR_MODE_10BIT	Use 10-bit addressing mode.

i2c_slave_event_t

enum i2c_slave_event_t

Callback events

Enumerator
I2C_SLAVE_EVENT_ABORTED	A transfer was aborted.
I2C_SLAVE_EVENT_RX_COMPLETE	A receive operation was completed successfully.
I2C_SLAVE_EVENT_TX_COMPLETE	A transmit operation was completed successfully.
I2C_SLAVE_EVENT_RX_REQUEST	A read operation expected from slave. Detected a write from master.
I2C_SLAVE_EVENT_TX_REQUEST	A write operation expected from slave. Detected a read from master.
I2C_SLAVE_EVENT_RX_MORE_REQUEST	A read operation expected from slave. Master sends out more data than configured to be read in slave.
I2C_SLAVE_EVENT_TX_MORE_REQUEST	A write operation expected from slave. Master requests more data than configured to be written by slave.
I2C_SLAVE_EVENT_GENERAL_CALL	General Call address received from Master. Detected a write from master.