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)