API Reference

Normative

The watchdog driver API contract. A conformant driver MUST provide these types and functions with the behavior described. Function and type signatures are extracted from the driver headers with Doxygen/Breathe. Keywords per Requirement Keywords; behavioral rules in Wdg — Requirements; error codes in Errors.

Data types at a glance

Type	Kind	Purpose
Wdg_ConfigType	struct	Root configuration structure (build-time; Wdg_Init takes NULL_PTR).
Wdg_ModeType	enum	Watchdog mode (OFF / NORMAL / ALTERNATIVE).

API at a glance

Function	Group	Purpose
Wdg_Init	Initialization	Initialize the driver and watchdog HW in the default mode.
Wdg_SetMode	Mode and timeout	Switch the watchdog mode.
Wdg_UpdateTimeout	Mode and timeout	Refresh the reset timeout.
Wdg_FeedHw	Mode and timeout	Trigger the HW periodically (logical strategy only).

Expected interfaces at a glance

Integration interfaces the integrator MUST provide where applicable (CHI-WDG-MUST-06); all are documented in the general reference. Interface names are configurable via the driver configuration.

Function	Kind	Purpose
LogM_Report	Common (optional)	Reports development errors with a log level.
<Mip>_EnterCriticalSection / <Mip>_ExitCriticalSection	Common (optional)	Bracket sections requiring exclusive access — see critical sections.

For an external watchdog the driver may additionally depend on a bus interface driver (e.g. SPI or I2C) it is configured to control the hardware through.

Data types

Wdg_ConfigType

struct Wdg_ConfigType

Configuration structure type.

Configuration variants are selected at build time; Wdg_Init currently takes NULL_PTR. Available via: Wdg.h

Wdg_ModeType

enum Wdg_ModeType

Mode type of watchdog hardware.

Values:

enumerator WDG_MODE_OFF = 0x00

Watchdog hardware is disabled (switched off)

enumerator WDG_MODE_NORMAL = 0x01

Watchdog hardware is in normal mode. Typically used during application running.

enumerator WDG_MODE_ALTERNATIVE = 0x02

Watchdog hardware is in alternative mode. Typically used during startup or standby sequence.

Available via: WdgIf_DriverTypes.h

Initialization

Wdg_Init

void Wdg_Init(const Wdg_ConfigType *configPtr)

Initializes the module.

Sync/Async:

Synchronous

Reentrancy:

Non Reentrant

Service ID [hex]:

0x00

Development error(s):

• WDG_DEVERR_DRIVER_STATE WdgDrv is initialized already

• WDG_DEVERR_PARAM_POINTER configPtr argument is not NULL pointer

Parameters:

configPtr – [in] Pointer to the configuration structure. This parameter is intended for future extensions to support runtime-selectable configuration variants, which allow the selection and initialization of specific variants during runtime. As this functionality is not currently supported, a NULL_PTR SHALL be provided.

Returns:

None.

When to call: once, before any other watchdog function. configPtr MUST be NULL_PTR.

Effect: initialises the driver and watchdog hardware, applying the configured default mode and initial timeout. Errors: see Errors. Available via: Wdg.h

Mode and timeout

Wdg_SetMode

Std_ReturnType Wdg_SetMode(Wdg_ModeType mode)

Switches the watchdog into the specified mode.

Sync/Async:

Synchronous

Reentrancy:

Non Reentrant

Service ID [hex]:

0x01

Development error(s):

• WDG_DEVERR_DRIVER_STATE WdgDrv is not initialized

• WDG_DEVERR_PARAM_MODE The given mode is not supported

Parameters:

mode – [in] Watchdog mode to be switched to

Return values:

• E_OK – Other than development error

• E_NOT_OK – In case of development error.

Returns:

Std_ReturnType.

Effect: switches the watchdog to mode, applies its hardware settings, and resets the timeout to the mode’s default. Returns: E_OK if accepted, else E_NOT_OK (development error). For the logical strategy, if the previous timeout has already expired the mode is not changed. Errors: see Errors. Available via: Wdg.h

Wdg_UpdateTimeout

void Wdg_UpdateTimeout(uint16 timeout)

Specifies how long watchdog reset is suspended. Watchdog reset gets delayed till the new timeout has been expired.

Sync/Async:

Synchronous

Reentrancy:

Non Reentrant

Service ID [hex]:

0x03

Development error(s):

• WDG_DEVERR_DRIVER_STATE WdgDrv is not initialized

• WDG_DEVERR_PARAM_TIMEOUT Given timeout value is over than supported maximum timeout value in the configuration and current mode.

Parameters:

timeout – [in] Timeout value (milliseconds) for watchdog hardware timeout.

Returns:

None.

Effect: delays the watchdog reset until timeout milliseconds elapse (bounded by the configured maximum_timeout). timeout = 0 requests an (almost) immediate reset. For the logical strategy, an already-expired previous timeout is not overwritten. Errors: see Errors. Available via: Wdg.h

Wdg_FeedHw

void Wdg_FeedHw(void)

Trigger watchdog hardware. Intended to be called from periodic timer handler. This interface is only required for “logical timeout management”. “Direct timeout management” does not use this interface.

Sync/Async:

Synchronous

Reentrancy:

Non Reentrant

Service ID [hex]:

0x05

Development error(s):

• WDG_DEVERR_DRIVER_STATE WdgDrv is not initialized

Parameters:

None –

Returns:

None.

When to call: periodically, from the upper layer’s timer handler — logical strategy only (the direct strategy does not use it). It decrements the logical timeout by the call interval and re-triggers the hardware only while the timeout has not expired. Setting up the timer is the upper layer’s responsibility. Errors: see Errors. Available via: Wdg.h