LIN Interface

Detailed Description

Interface for LIN communications.

Summary

The LIN interface provides common APIs for LIN HAL drivers. The LIN interface supports the following features:

• Half-duplex master or slave LIN communication
• Interrupt driven transmit/receive processing
• Callback function with returned event code and data
• Checksum generation and validation (standard or enhanced)

Data Structures
struct	lin_transfer_params_t
struct	lin_callback_args_t
struct	lin_cfg_t
struct	lin_api_t
struct	lin_instance_t

Typedefs
typedef void	lin_ctrl_t

Enumerations
enum	lin_mode_t
enum	lin_checksum_type_t
enum	lin_event_t

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Data Structure Documentation

lin_transfer_params_t

struct lin_transfer_params_t

LIN Transfer Parameters

Data Fields
uint8_t	id	The unprotected frame ID associated with the information frame transfer.
uint8_t *	p_information	Pointer to rx or tx buffer associated with the information frame transfer.
uint8_t	num_bytes	Length of buffer pointed to by p_information, in bytes.
lin_checksum_type_t	checksum_type	Checksum type to use for checksum generation (when writing frame) or validation (when reading frame). See lin_checksum_type_t.

lin_callback_args_t

struct lin_callback_args_t

LIN Callback Arguments

Data Fields
uint32_t	channel	Channel number.
lin_event_t	event	Event code.
uint8_t	bytes_received	Valid for the following events: LIN_EVENT_RX_INFORMATION_FRAME_COMPLETE LIN_EVENT_ERR_FRAMING LIN_EVENT_ERR_INVALID_CHECKSUM Contains the number of information bytes received for an information frame reception.
uint8_t	pid	For LIN slave: Contains the most recently received protected identifier For LIN master: Contains the most recently transmitted protected identifier.
uint8_t	checksum	Received checksum. Valid for the following events: LIN_EVENT_RX_INFORMATION_FRAME_COMPLETE LIN_EVENT_ERR_INVALID_CHECKSUM.
void const *	p_context	Context provided to user during callback.

lin_cfg_t

struct lin_cfg_t

LIN configuration block

Data Fields
uint8_t	channel
	Select a channel corresponding to the channel number of the hardware.
lin_mode_t	mode
	Driver mode (master or slave)
void(*	p_callback )(lin_callback_args_t *p_args)
	Pointer to callback function.
void const *	p_context
	User defined context passed into callback function.
void const *	p_extend
	LIN hardware dependent configuration.

lin_api_t

struct lin_api_t

Interface definition for LIN

Data Fields
fsp_err_t(*	open )(lin_ctrl_t *const p_ctrl, lin_cfg_t const *const p_cfg)
fsp_err_t(*	startFrameWrite )(lin_ctrl_t *const p_ctrl, uint8_t const id)
fsp_err_t(*	informationFrameWrite )(lin_ctrl_t *const p_ctrl, const lin_transfer_params_t *const p_transfer_params)
fsp_err_t(*	informationFrameRead )(lin_ctrl_t *const p_ctrl, lin_transfer_params_t *const p_transfer_params)
fsp_err_t(*	communicationAbort )(lin_ctrl_t *const p_ctrl)
fsp_err_t(*	callbackSet )(lin_ctrl_t *const p_ctrl, void(*p_callback)(lin_callback_args_t *), void const *const p_context, lin_callback_args_t *const p_callback_memory)
fsp_err_t(*	close )(lin_ctrl_t *const p_ctrl)

Field Documentation

open

fsp_err_t(* lin_api_t::open) (lin_ctrl_t *const p_ctrl, lin_cfg_t const *const p_cfg)

Open LIN device. Transmission and reception of LIN frames is enabled upon successful return from this function.

Parameters

[in,out]	p_ctrl	Pointer to the LIN control block. Must be declared by user. Value set here.
[in]	p_cfg	Pointer to LIN configuration structure. All elements of this structure must be set by user.

startFrameWrite

fsp_err_t(* lin_api_t::startFrameWrite) (lin_ctrl_t *const p_ctrl, uint8_t const id)

Begin non-blocking transmission of the LIN start frame. The start frame consists of the break pattern, sync word, and protected frame identifier (PID). The unprotected identifier should be supplied. The driver will compute the PID.

When the start frame has been transmitted, the callback is called with event LIN_EVENT_TX_START_FRAME_COMPLETE.

Parameters

[in,out]	p_ctrl	Pointer to the LIN control block.
[in]	id	Unprotected frame identifier

informationFrameWrite

fsp_err_t(* lin_api_t::informationFrameWrite) (lin_ctrl_t *const p_ctrl, const lin_transfer_params_t *const p_transfer_params)

Begin non-blocking transmission of the LIN information frame.

The write buffer is used until the write is complete. When the write completes successfully (all bytes are fully transmitted on the wire) the callback is called with event LIN_EVENT_TX_INFORMATION_FRAME_COMPLETE.

Parameters

[in,out]	p_ctrl	Pointer to the LIN control block.
[in]	p_transfer_params	Pointer to parameters required for the write transaction.

informationFrameRead

fsp_err_t(* lin_api_t::informationFrameRead) (lin_ctrl_t *const p_ctrl, lin_transfer_params_t *const p_transfer_params)

Begin non-blocking read of information frame bytes.

When a read completes successfully, the callback is called with event LIN_EVENT_RX_INFORMATION_FRAME_COMPLETE.

Parameters

[in]	p_ctrl	Pointer to the LIN control block for the channel.
[in]	p_transfer_params	Pointer to parameters required for the read transaction.

communicationAbort

fsp_err_t(* lin_api_t::communicationAbort) (lin_ctrl_t *const p_ctrl)

Abort ongoing transfer.

Parameters

[in]

p_ctrl

Pointer to the LIN control block.

callbackSet

fsp_err_t(* lin_api_t::callbackSet) (lin_ctrl_t *const p_ctrl, void(*p_callback)(lin_callback_args_t *), void const *const p_context, lin_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 LIN 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(* lin_api_t::close) (lin_ctrl_t *const p_ctrl)

Close LIN device.

Parameters

[in]

p_ctrl

Pointer to the LIN control block.

lin_instance_t

struct lin_instance_t

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

Data Fields
lin_ctrl_t *	p_ctrl	Pointer to the control structure for this instance.
lin_cfg_t const *	p_cfg	Pointer to the configuration structure for this instance.
lin_api_t const *	p_api	Pointer to the API structure for this instance.

Typedef Documentation

lin_ctrl_t

typedef void lin_ctrl_t

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

Enumeration Type Documentation

lin_mode_t

enum lin_mode_t

LIN driver mode

Enumerator
LIN_MODE_SLAVE	Slave mode.
LIN_MODE_MASTER	Master mode.

lin_checksum_type_t

enum lin_checksum_type_t

LIN checksum type

Enumerator
LIN_CHECKSUM_TYPE_CLASSIC	8 bit LIN classic checksum over information bytes only
LIN_CHECKSUM_TYPE_ENHANCED	8 bit LIN enhanced checksum over information bytes and PID
LIN_CHECKSUM_TYPE_NONE	Skip driver checksum generation/validation.

lin_event_t

enum lin_event_t

LIN Event codes

Enumerator
LIN_EVENT_NONE	No event present.
LIN_EVENT_RX_START_FRAME_COMPLETE	Start frame received event.
LIN_EVENT_RX_INFORMATION_FRAME_COMPLETE	Information frame received event.
LIN_EVENT_TX_START_FRAME_COMPLETE	Start frame transmission complete event.
LIN_EVENT_TX_INFORMATION_FRAME_COMPLETE	Information transmission complete event.
LIN_EVENT_ERR_INVALID_CHECKSUM	Information frame received successfully, but checksum was invalid.
LIN_EVENT_ERR_BUS_COLLISION_DETECTED	Bus collision detection event.
LIN_EVENT_ERR_FRAMING	Framing error event.
LIN_EVENT_ERR_COUNTER_OVERFLOW	Counter overflow event.
LIN_EVENT_ERR_OVERRUN	Overrun error event.
LIN_EVENT_ERR_PARITY	Parity error event (start frame only, LIN information is sent without parity)