DDI_INTR_ENABLE(9F) Kernel Functions for Drivers DDI_INTR_ENABLE(9F)

NAME

ddi_intr_enable, ddi_intr_block_enable, ddi_intr_disable,
ddi_intr_block_disable - enable or disable a given interrupt or range of
interrupts

SYNOPSIS

#include <sys/types.h>
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>


int ddi_intr_enable(ddi_intr_handle_t h);


int ddi_intr_block_enable(ddi_intr_handle_t *h_array, int count);


int ddi_intr_disable(ddi_intr_handle_t h);


int ddi_intr_block_disable(ddi_intr_handle_t *h_array, int count);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

ddi_intr_enable()

h
DDI interrupt handle


ddi_intr_block_enable()

h_array
Pointer to an array of DDI interrupt handles


count
Number of interrupts


ddi_intr_disable()

h
DDI interrupt handle


ddi_intr_block_disable()

h_array
Pointer to an array of DDI interrupt handles


count
Number of interrupts

DESCRIPTION

The ddi_intr_enable() function enables the interrupt given by the
interrupt handle h.


The ddi_intr_block_enable() function enables a range of interrupts given
by the count and h_array arguments, where count must be at least 1 and
h_array is pointer to a count-sized array of interrupt handles.


The ddi_intr_block_enable() function can be used only if the device or
host bridge supports the block enable/disable feature. The
ddi_intr_get_cap() function returns the RO flag DDI_INTR_FLAG_BLOCK if
the device or host bridge supports the interrupt block enable/disable
feature for the given interrupt type. The ddi_intr_block_enable()
function is useful for enabling MSI interrupts when the optional per-
vector masking capability is not supported.


The ddi_intr_enable() or ddi_intr_block_enable() functions must be called
after the required interrupt resources are allocated with
ddi_intr_alloc(), the interrupt handlers are added through
ddi_intr_add_handler(), and the required locks are initialized by
mutex(9F) or rwlock(9F).


Once enabled by either of the enable calls, the interrupt can be taken
and passed to the driver's interrupt service routine. Enabling an
interrupt implies clearing any system or device mask bits associated with
the interrupt.


The ddi_intr_disable() function disables the interrupt given by the
interrupt handle h.


The ddi_intr_block_disable() function disables a range of interrupts
given by the count and h_array arguments, where count must be at least 1
and h_array is pointer to a count-sized array of interrupt handles.


The ddi_intr_block_disable() function can be used only if the device or
host bridge supports the block enable/disable feature. The
ddi_intr_get_cap() function returns the RO flag DDI_INTR_FLAG_BLOCK if
the device or host bridge supports the interrupt block enable/disable
feature for the given interrupt type. The ddi_intr_block_disable()
function is useful for disabling MSI interrupts when the optional per-
vector masking capability is not supported.


The ddi_intr_disable() or ddi_intr_block_disable() functions must be
called before removing the interrupt handler and freeing the
corresponding interrupt with ddi_intr_remove_handler() and
ddi_intr_free(), respectively. The ddi_intr_block_disable() function
should be called if the ddi_intr_block_enable() function was used to
enable the interrupts.

RETURN VALUES

The ddi_intr_enable(), ddi_intr_block_enable(), ddi_intr_disable(), and
ddi_intr_block_disable() functions return:

DDI_SUCCESS
On success.


DDI_EINVAL
On encountering invalid input parameters.


DDI_FAILURE
On any implementation specific failure.

CONTEXT

The ddi_intr_enable(), ddi_intr_block_enable(), ddi_intr_disable(), and
ddi_intr_block_disable() functions can be called from kernel non-
interrupt context.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Committed |
+--------------------+-----------------+

SEE ALSO

attributes(7), ddi_intr_add_handler(9F), ddi_intr_alloc(9F),
ddi_intr_dup_handler(9F), ddi_intr_free(9F), ddi_intr_get_cap(9F),
ddi_intr_remove_handler(9F), mutex(9F), rwlock(9F)


Writing Device Drivers

NOTES

Consumers of these interfaces should verify that the return value is not
equal to DDI_SUCCESS. Incomplete checking for failure codes could result
in inconsistent behavior among platforms.


If a device driver that uses MSI and MSI-X interrupts resets the device,
the device might reset its configuration space modifications. Such a
reset could cause a device driver to lose any MSI and MSI-X interrupt
usage settings that have been applied.


April 22, 2005 DDI_INTR_ENABLE(9F)