te
Copyright (c) 2004, Sun Microsystems, Inc.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
getinfo - get device driver information

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



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

illumos DDI specific (illumos DDI). This entry point is required for drivers which export cb_ops(9S) entry points. dip cmd arg resultp 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.

getinfo() should return: DDI_SUCCESS DDI_FAILURE 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);
}

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

Writing Device Drivers

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.