xref: /illumos-gate/usr/src/man/man9f/ddi_create_minor_node.9f (revision b93865c3d90e9b0d73e338c9abb3293c35c571a8)
te
Copyright (c) 2004, Sun Microsystems, Inc. All Rights Reserved
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]
DDI_CREATE_MINOR_NODE 9F "May 01, 2020"
NAME
ddi_create_minor_node - Create a minor node for this device
SYNOPSIS
#include <sys/stat.h>
#include <sys/sunddi.h>



int ddi_create_minor_node(dev_info_t *dip, const char *name,
 int spec_type, minor_t minor_num, const char *node_type,
 int flag);
INTERFACE LEVEL
illumos DDI specific (illumos DDI).
PARAMETERS
dip

A pointer to the device's dev_info structure.

name

The name of this particular minor device.

spec_type

S_IFCHR or S_IFBLK for character or block minor devices respectively.

minor_num

The minor number for this particular minor device.

node_type

Any string literal that uniquely identifies the type of node. The following predefined node types are provided with this release: DDI_NT_SERIAL

For serial ports

DDI_NT_SERIAL_MB

For on board serial ports

DDI_NT_SERIAL_DO

For dial out ports

DDI_NT_SERIAL_MB_DO

For on board dial out ports

DDI_NT_BLOCK

For hard disks

DDI_NT_BLOCK_CHAN

For hard disks with channel or target numbers

DDI_NT_CD

For CDROM drives

DDI_NT_CD_CHAN

For CDROM drives with channel or target numbers

DDI_NT_FD

For floppy disks

DDI_NT_TAPE

For tape drives

DDI_NT_NET

For DLPI style 1 or style 2 network devices

DDI_NT_DISPLAY

For display devices

DDI_PSEUDO

For pseudo devices

flag

If the device is a clone device then this flag is set to CLONE_DEV else it is set to 0.

DESCRIPTION
ddi_create_minor_node() provides the necessary information to enable the system to create the /dev and /devices hierarchies. The name is used to create the minor name of the block or character special file under the /devices hierarchy. At-sign (@), slash (/), and space are not allowed. The spec_type specifies whether this is a block or character device. The minor_num is the minor number for the device. The node_type is used to create the names in the /dev hierarchy that refers to the names in the /devices hierarchy. See disks(8), ports(8), tapes(8), devlinks(8). Finally flag determines if this is a clone device or not, and what device class the node belongs to.
RETURN VALUES
ddi_create_minor_node() returns: DDI_SUCCESS

Was able to allocate memory, create the minor data structure, and place it into the linked list of minor devices for this driver.

DDI_FAILURE

Minor node creation failed.

CONTEXT
The ddi_create_minor_node() function can be called from user context. It is typically called from attach(9E) or ioctl(9E).
EXAMPLES
Example 1 Create Data Structure Describing Minor Device with Minor Number of 0

The following example creates a data structure describing a minor device called foo which has a minor number of 0. It is of type DDI_NT_BLOCK (a block device) and it is not a clone device.

ddi_create_minor_node(dip, "foo", S_IFBLK, 0, DDI_NT_BLOCK, 0);
SEE ALSO
add_drv (8), devlinks (8), disks (8), drvconfig (8), ports (8), tapes (8), attach (9E), ddi_remove_minor_node (9F)

Writing Device Drivers

NOTES
If the driver is for a network device (node_type DDI_NT_NET), note that the driver name will undergo the driver name constraints identified in the NOTES section of dlpi(4P). Additionally, the minor name must match the driver name for a DLPI style 2 provider. If the driver is a DLPI style 1 provider, the minor name must also match the driver name with the exception that the ppa is appended to the minor name.

Non-gld(4D)-based DLPI network streams drivers are encouraged to switch to gld(4D). Failing this, a driver that creates DLPI style-2 minor nodes must specify CLONE_DEV for its style-2 ddi_create_minor_node() 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(9E) 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(9E) implementation. For drivers that do not follow these rules, the results of a modunload(8) of the driver or a cfgadm(8) remove of hardware controlled by the driver are undefined.

WARNING
Drivers must remove references to GLOBAL_DEV, NODEBOUND_DEV, NODESPECIFIC_DEV, and ENUMERATED_DEV to compile.