xref: /freebsd/share/man/man9/devclass.9 (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1.\" -*- nroff -*-
2.\"
3.\" Copyright (c) 1998 Doug Rabson
4.\"
5.\" All rights reserved.
6.\"
7.\" This program is free software.
8.\"
9.\" Redistribution and use in source and binary forms, with or without
10.\" modification, are permitted provided that the following conditions
11.\" are met:
12.\" 1. Redistributions of source code must retain the above copyright
13.\"    notice, this list of conditions and the following disclaimer.
14.\" 2. Redistributions in binary form must reproduce the above copyright
15.\"    notice, this list of conditions and the following disclaimer in the
16.\"    documentation and/or other materials provided with the distribution.
17.\"
18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28.\"
29.\" $FreeBSD$
30.\"
31.Dd June 16, 1998
32.Dt DEVCLASS 9
33.Os
34.Sh NAME
35.Nm devclass
36.Nd object representing a class of devices
37.Sh SYNOPSIS
38.Vt typedef struct devclass *devclass_t ;
39.Sh DESCRIPTION
40The
41.Vt devclass
42object has two main functions in the system.
43The first is to manage
44the allocation of unit numbers for device instances and the second is
45to hold the list of device drivers for a particular bus type.
46Each
47.Vt devclass
48has a name and there cannot be two devclasses with the same name.
49This ensures that unique unit numbers are allocated to device
50instances.
51.Pp
52Beware that this means
53.Vt devclass
54must be the same for different bus attachments of the same device driver.
55.Sh SEE ALSO
56.Xr devclass_add_driver 9 ,
57.Xr devclass_delete_driver 9 ,
58.Xr devclass_find 9 ,
59.Xr devclass_find_driver 9 ,
60.Xr devclass_get_device 9 ,
61.Xr devclass_get_devices 9 ,
62.Xr devclass_get_maxunit 9 ,
63.Xr devclass_get_name 9 ,
64.Xr devclass_get_softc 9 ,
65.Xr device 9 ,
66.Xr driver 9
67.Sh AUTHORS
68This manual page was written by
69.An Doug Rabson .
70