opensolaris man page for getinfo

getinfo(9E)							Driver Entry Points						       getinfo(9E)

NAME
       getinfo - get device driver information

SYNOPSIS
       #include <sys/ddi.h>
       #include <sys/sunddi.h>

       int prefixgetinfo(dev_info_t *dip, ddi_info_cmd_t cmd,
	    void *arg, void **resultp);

INTERFACE LEVEL
       Solaris DDI specific (Solaris DDI). This entry point is required for drivers which export cb_ops(9S) entry points.

ARGUMENTS
       dip	  Do not use.

       cmd	  Command argument - valid command values are DDI_INFO_DEVT2DEVINFO and DDI_INFO_DEVT2INSTANCE.

       arg	  Command specific argument.

       resultp	  Pointer to where the requested information is stored.

DESCRIPTION
       When  cmd  is  set  to  DDI_INFO_DEVT2DEVINFO, getinfo() should return the dev_info_t pointer associated with the dev_t arg. The dev_info_t
       pointer should be returned in the field pointed to by resultp.

       When cmd is set to DDI_INFO_DEVT2INSTANCE, getinfo() should return the instance number associated with the dev_t arg. The  instance  number
       should be returned in the field pointed to by resultp.

       Drivers	which  do  not	export	cb_ops(9S)  entry points are not required to provide a getinfo() entry point, and may use nodev(9F) in the
       devo_getinfo field of the dev_ops(9S) structure. A SCSI HBA driver is an example of a driver which is not required  to  provide	cb_ops(9S)
       entry points.

RETURN VALUES
       getinfo() should return:

       DDI_SUCCESS    on success.

       DDI_FAILURE    on failure.

EXAMPLES
       Example 1 getinfo() implementation

	 /*ARGSUSED*/
	 static int
	 rd_getinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, 
	 void **resultp)
	 {
		/* Note that in this simple example
		 * the minor number is the instance
		 * number.    */

	      devstate_t *sp;
	      int error = DDI_FAILURE;
	      switch (infocmd) {
	      case DDI_INFO_DEVT2DEVINFO:
		   if ((sp = ddi_get_soft_state(statep,
		       getminor((dev_t) arg))) != NULL) {
			  *resultp = sp->devi;
			  error = DDI_SUCCESS;
		   } else
			  *result = NULL;
		   break;

	      case DDI_INFO_DEVT2INSTANCE:
		   *resultp = (void *) (uintptr_t) getminor((dev_t) arg);
		   error = DDI_SUCCESS;
		   break;
	      }

	      return (error);
	 }

SEE ALSO
       ddi_no_info(9F), nodev(9F), cb_ops(9S), dev_ops(9S)

       Writing Device Drivers

NOTES
       Non-gld(7D)-based  DLPI	network  streams  drivers  are	encouraged  to switch to gld(7D). Failing this, a driver that creates DLPI style-2
       minor nodes must specify CLONE_DEV for its style-2 ddi_create_minor_node(9F) nodes and use qassociate(9F).  A  driver  that  supports  both
       style-1	and  style-2 minor nodes should return DDI_FAILURE for DDI_INFO_DEVT2INSTANCE and DDI_INFO_DEVT2DEVINFO getinfo() calls to style-2
       minor nodes. (The correct association is already established by qassociate(9F)). A driver that only supports style-2 minor  nodes  can  use
       ddi_no_info(9F)	for its getinfo() implementation. For drivers that do not follow these rules, the results of a modunload(1M) of the driver
       or a cfgadm(1M) remove of hardware controlled by the driver are undefined.

SunOS 5.11							    16 Jan 2008 						       getinfo(9E)