man pages section 9: DDI and DKI Kernel Functions

ddi_add_intr(9F)

Name

ddi_add_intr, ddi_get_iblock_cookie, ddi_remove_intr– hardware interrupt handling routines

Synopsis

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



int ddi_get_iblock_cookie(dev_info_t *dip, uint_t inumber,
      ddi_iblock_cookie_t *iblock_cookiep);

int ddi_add_intr(dev_info_t *dip, uint_t inumber, ddi_iblock_cookie_t 
     *iblock_cookiep, ddi_idevice_cookie_t *idevice_cookiep, 
     uint_t (*int_handler) (caddr_t),caddr_t int_handler_arg);

void ddi_remove_intr(dev_info_t *dip, uint_t inumber, 
     ddi_iblock_cookie_t iblock_cookie);

Interface Level

Solaris DDI specific (Solaris DDI). These interfaces are obsolete. Use the new interrupt interfaces referenced in Intro(9F). Refer to Writing Device Drivers for more information.

Parameters

For ddi_get_iblock_cookie():

dip: Pointer to dev_info structure.
inumber: Interrupt number.
iblock_cookiep: Pointer to an interrupt block cookie.

For ddi_add_intr():

dip: Pointer to dev_info structure.
inumber: Interrupt number.
iblock_cookiep: Optional pointer to an interrupt block cookie where a returned interrupt block cookie is stored.
idevice_cookiep: Optional pointer to an interrupt device cookie where a returned interrupt device cookie is stored.
int_handler: Pointer to interrupt handler.
int_handler_arg: Argument for interrupt handler.

For ddi_remove_intr():

dip: Pointer to dev_info structure.
inumber: Interrupt number.
iblock_cookie: Block cookie which identifies the interrupt handler to be removed.

Description

ddi_get_iblock_cookie( )

ddi_get_iblock_cookie() retrieves the interrupt block cookie associated with a particular interrupt specification. This routine should be called before ddi_add_intr() to retrieve the interrupt block cookie needed to initialize locks (mutex(9F), rwlock(9F)) used by the interrupt routine. The interrupt number inumber determines for which interrupt specification to retrieve the cookie. inumber is associated with information provided either by the device (see sbus(4)) or the hardware configuration file (see sysbus(4), isa(4), and driver.conf(4)). If only one interrupt is associated with the device, inumber should be 0.

On a successful return, *iblock_cookiep contains information needed for initializing locks associated with the interrupt specification corresponding to inumber (see mutex_init(9F) and rw_init(9F)). The driver can then initialize locks acquired by the interrupt routine before calling ddi_add_intr() which prevents a possible race condition where the driver's interrupt handler is called immediately after the driver has called ddi_add_intr() but before the driver has initialized the locks. This may happen when an interrupt for a different device occurs on the same interrupt level. If the interrupt routine acquires the lock before the lock has been initialized, undefined behavior may result.

ddi_add_intr( )

ddi_add_intr() adds an interrupt handler to the system. The interrupt number inumber determines which interrupt the handler will be associated with. (Refer to ddi_get_iblock_cookie() above.)

On a successful return, iblock_cookiep contains information used for initializing locks associated with this interrupt specification (see mutex_init(9F) and rw_init(9F)). Note that the interrupt block cookie is usually obtained using ddi_get_iblock_cookie() to avoid the race conditions described above (refer to ddi_get_iblock_cookie() above). For this reason, iblock_cookiep is no longer useful and should be set to NULL.

On a successful return, idevice_cookiep contains a pointer to a ddi_idevice_cookie_t structure (see ddi_idevice_cookie(9S)) containing information useful for some devices that have programmable interrupts. If idevice_cookiep is set to NULL, no value is returned.

The routine intr_handler, with its argument int_handler_arg, is called upon receipt of the appropriate interrupt. The interrupt handler should return DDI_INTR_CLAIMED if the interrupt was claimed, DDI_INTR_UNCLAIMED otherwise.

If successful, ddi_add_intr() returns DDI_SUCCESS. If the interrupt information cannot be found on the sun4u architecture, either DDI_INTR_NOTFOUND or DDI_FAILURE can be returned. On i86pc and sun4m architectures, if the interrupt information cannot be found, DDI_INTR_NOTFOUND is returned.

ddi_remove_intr( )

ddi_remove_intr() removes an interrupt handler from the system. Unloadable drivers should call this routine during their detach(9E) routine to remove their interrupt handler from the system.

The device interrupt routine for this instance of the device will not execute after ddi_remove_intr() returns. ddi_remove_intr() may need to wait for the device interrupt routine to complete before returning. Therefore, locks acquired by the interrupt handler should not be held across the call to ddi_remove_intr() or deadlock may result.

For All Three Functions:

For certain bus types, you can call these DDI functions from a high-interrupt context. These types include ISA and SBus buses. See sysbus(4), isa(4), and sbus(4) for details.

Return Values

ddi_add_intr() and ddi_get_iblock_cookie() return:

DDI_SUCCESS: On success.
DDI_INTR_NOTFOUND: On failure to find the interrupt.
DDI_FAILURE: On failure. DDI_FAILURE can also be returned on failure to find interrupt (sun4u).

Context

ddi_add_intr(), ddi_remove_intr(), and ddi_get_iblock_cookie() can be called from user or kernel context.

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Obsolete

Notes

ddi_get_iblock_cookie() must not be called after the driver adds an interrupt handler for the interrupt specification corresponding to inumber.

All consumers of these interfaces, checking return codes, should verify return_code != DDI_SUCCESS. Checking for specific failure codes can result in inconsistent behaviors among platforms.

Bugs

The idevice_cookiep should really point to a data structure that is specific to the bus architecture that the device operates on. Currently the SBus and PCI buses are supported and a single data structure is used to describe both.

SunOS 5.10 Last Revised 2 Oct 2007