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 *) getminor((dev_t) arg);
               error = DDI_SUCCESS;
               break;
          }

          return (error);
     }

SEE ALSO

     nodev(9F), cb_ops(9S), dev_ops(9S)

     Writing Device Drivers