Interrupt Management Services

Collaboration diagram for Interrupt Management Services:

Macros
#define	rtdm_irq_get_arg(irq_handle, type)   ((type *)irq_handle->cookie)
	Retrieve IRQ handler argument. More...

Typedefs
typedef int(*	rtdm_irq_handler_t) (rtdm_irq_t *irq_handle)
	Interrupt handler. More...

Functions
int	rtdm_irq_request (rtdm_irq_t *irq_handle, unsigned int irq_no, rtdm_irq_handler_t handler, unsigned long flags, const char *device_name, void *arg)
	Register an interrupt handler. More...
int	rtdm_irq_free (rtdm_irq_t *irq_handle)
	Release an interrupt handler. More...
int	rtdm_irq_enable (rtdm_irq_t *irq_handle)
	Enable interrupt line. More...
int	rtdm_irq_disable (rtdm_irq_t *irq_handle)
	Disable interrupt line. More...

RTDM_IRQTYPE_xxx
Interrupt registrations flags
#define	RTDM_IRQTYPE_SHARED   XN_IRQTYPE_SHARED
	Enable IRQ-sharing with other real-time drivers.
#define	RTDM_IRQTYPE_EDGE   XN_IRQTYPE_EDGE
	Mark IRQ as edge-triggered, relevant for correct handling of shared edge-triggered IRQs.

RTDM_IRQ_xxx
Return flags of interrupt handlers
#define	RTDM_IRQ_NONE   XN_IRQ_NONE
	Unhandled interrupt.
#define	RTDM_IRQ_HANDLED   XN_IRQ_HANDLED
	Denote handled interrupt.
#define	RTDM_IRQ_DISABLE   XN_IRQ_DISABLE
	Request interrupt disabling on exit.

Detailed Description

Macro Definition Documentation

rtdm_irq_get_arg

#define rtdm_irq_get_arg	(		irq_handle,
			type
	)		((type *)irq_handle->cookie)

Retrieve IRQ handler argument.

Parameters

irq_handle	IRQ handle
type	Type of the pointer to return

Returns

The argument pointer registered on rtdm_irq_request() is returned, type-casted to the specified type.

Tags

unrestricted

Referenced by a4l_get_time().

Typedef Documentation

rtdm_irq_handler_t

typedef int(* rtdm_irq_handler_t) (rtdm_irq_t *irq_handle)

Interrupt handler.

Parameters

[in]

irq_handle

IRQ handle as returned by rtdm_irq_request()

Returns

0 or a combination of RTDM_IRQ_xxx flags

Function Documentation

rtdm_irq_disable()

int rtdm_irq_disable

(

rtdm_irq_t *

irq_handle

)

Disable interrupt line.

Parameters

[in,out]

irq_handle

IRQ handle as returned by rtdm_irq_request()

Returns

0 on success, otherwise negative error code

Note

This service is for exceptional use only. Drivers should always prefer interrupt masking at device level (via corresponding control registers etc.) over masking at line level. Keep in mind that the latter is incompatible with IRQ line sharing and can also be more costly as interrupt controller access requires broader synchronization. Also, such service is solely available from secondary mode. The caller is responsible for excluding such conflicts.

Tags

secondary-only

Referenced by udd_notify_event().

rtdm_irq_enable()

int rtdm_irq_enable

(

rtdm_irq_t *

irq_handle

)

Enable interrupt line.

Parameters

[in,out]

irq_handle

IRQ handle as returned by rtdm_irq_request()

Returns

0 on success, otherwise negative error code

Note

This service is for exceptional use only. Drivers should always prefer interrupt masking at device level (via corresponding control registers etc.) over masking at line level. Keep in mind that the latter is incompatible with IRQ line sharing and can also be more costly as interrupt controller access requires broader synchronization. Also, such service is solely available from secondary mode. The caller is responsible for excluding such conflicts.

Tags

secondary-only

Referenced by udd_notify_event().

rtdm_irq_free()

int rtdm_irq_free

(

rtdm_irq_t *

irq_handle

)

Release an interrupt handler.

Parameters

[in,out]

irq_handle

IRQ handle as returned by rtdm_irq_request()

Returns

0 on success, otherwise negative error code

Note

The caller is responsible for shutting down the IRQ source at device level before invoking this service. In turn, rtdm_irq_free ensures that any pending event on the given IRQ line is fully processed on return from this service.

Tags

secondary-only

Referenced by a4l_get_time(), and udd_unregister_device().

rtdm_irq_request()

int rtdm_irq_request	(	rtdm_irq_t *	irq_handle,
		unsigned int	irq_no,
		rtdm_irq_handler_t	handler,
		unsigned long	flags,
		const char *	device_name,
		void *	arg
	)

Register an interrupt handler.

This function registers the provided handler with an IRQ line and enables the line.

Parameters

[in,out]	irq_handle	IRQ handle
[in]	irq_no	Line number of the addressed IRQ
[in]	handler	Interrupt handler
[in]	flags	Registration flags, see RTDM_IRQTYPE_xxx for details
[in]	device_name	Device name to show up in real-time IRQ lists
[in]	arg	Pointer to be passed to the interrupt handler on invocation

Returns

0 on success, otherwise:

• -EINVAL is returned if an invalid parameter was passed.
• -EBUSY is returned if the specified IRQ line is already in use.

Tags

secondary-only

Referenced by a4l_get_time().