Timer Services
[Driver Development API]

Collaboration diagram for Timer Services:

RTDM_TIMERMODE_xxx
Timer operation modes
enum	rtdm_timer_mode { RTDM_TIMERMODE_RELATIVE = XN_RELATIVE, RTDM_TIMERMODE_ABSOLUTE = XN_ABSOLUTE, RTDM_TIMERMODE_REALTIME = XN_REALTIME }
Typedefs
typedef void(*	rtdm_timer_handler_t )(rtdm_timer_t *timer)
	Timer handler.
Functions
int	rtdm_timer_init (rtdm_timer_t *timer, rtdm_timer_handler_t handler, const char *name)
void	rtdm_timer_destroy (rtdm_timer_t *timer)
int	rtdm_timer_start (rtdm_timer_t *timer, nanosecs_abs_t expiry, nanosecs_rel_t interval, enum rtdm_timer_mode mode)
void	rtdm_timer_stop (rtdm_timer_t *timer)
int	rtdm_timer_start_in_handler (rtdm_timer_t *timer, nanosecs_abs_t expiry, nanosecs_rel_t interval, enum rtdm_timer_mode mode)
void	rtdm_timer_stop_in_handler (rtdm_timer_t *timer)

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Typedef Documentation

typedef void(* rtdm_timer_handler_t)(rtdm_timer_t *timer)

Timer handler.

Parameters:

[in]

timer

Timer handle as returned by rtdm_timer_init()

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Enumeration Type Documentation

enum rtdm_timer_mode

Enumerator:

RTDM_TIMERMODE_RELATIVE	Monotonic timer with relative timeout.
RTDM_TIMERMODE_ABSOLUTE	Monotonic timer with absolute timeout.
RTDM_TIMERMODE_REALTIME	Adjustable timer with absolute timeout.

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Function Documentation

void rtdm_timer_destroy

(

rtdm_timer_t *

timer

)

Destroy a timer

Parameters:

[in,out]

timer

Timer handle as returned by rtdm_timer_init() Environments: This service can be called from: - Kernel module initialization/cleanup code Kernel-based task User-space task (RT, non-RT) Rescheduling: never.

int rtdm_timer_init	(	rtdm_timer_t *	timer,
		rtdm_timer_handler_t	handler,
		const char *	name
	)

Initialise a timer

Parameters:

[in,out]	timer	Timer handle
[in]	handler	Handler to be called on timer expiry
[in]	name	Optional timer name

Returns:

0 on success, otherwise negative error code Environments: This service can be called from: - Kernel module initialization/cleanup code

• Kernel-based task
• User-space task (RT, non-RT) Rescheduling: never.

int rtdm_timer_start	(	rtdm_timer_t *	timer,
		nanosecs_abs_t	expiry,
		nanosecs_rel_t	interval,
		enum rtdm_timer_mode	mode
	)

Start a timer

Parameters:

[in,out]	timer	Timer handle as returned by rtdm_timer_init()
[in]	expiry	Firing time of the timer, mode defines if relative or absolute
[in]	interval	Relative reload value, > 0 if the timer shall work in periodic mode with the specific interval, 0 for one-shot timers
[in]	mode	Defines the operation mode, see RTDM_TIMERMODE_xxx for possible values

Returns:

0 on success, otherwise: - -ETIMEDOUT is returned if expiry describes an absolute date in the past.

Environments:

This service can be called from:

• Kernel module initialization/cleanup code
• Interrupt service routine
• Kernel-based task
• User-space task (RT, non-RT)

Rescheduling: never.

int rtdm_timer_start_in_handler	(	rtdm_timer_t *	timer,
		nanosecs_abs_t	expiry,
		nanosecs_rel_t	interval,
		enum rtdm_timer_mode	mode
	)

Start a timer from inside a timer handler

Parameters:

[in,out]	timer	Timer handle as returned by rtdm_timer_init()
[in]	expiry	Firing time of the timer, mode defines if relative or absolute
[in]	interval	Relative reload value, > 0 if the timer shall work in periodic mode with the specific interval, 0 for one-shot timers
[in]	mode	Defines the operation mode, see RTDM_TIMERMODE_xxx for possible values

Returns:

0 on success, otherwise: - -ETIMEDOUT is returned if expiry describes an absolute date in the past.

Environments:

This service can be called from:

• Timer handler

Rescheduling: never.

void rtdm_timer_stop

(

rtdm_timer_t *

timer

)

Stop a timer

Parameters:

[in,out]

timer

Timer handle as returned by rtdm_timer_init() Environments: This service can be called from: - Kernel module initialization/cleanup code Interrupt service routine Kernel-based task User-space task (RT, non-RT) Rescheduling: never.

void rtdm_timer_stop_in_handler

(

rtdm_timer_t *

timer

)

Stop a timer from inside a timer handler

Parameters:

[in,out]

timer

Timer handle as returned by rtdm_timer_init() Environments: This service can be called from: - Timer handler Rescheduling: never.

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