xref: /freebsd/share/man/man9/devclass.9 (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
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29.\" $FreeBSD$
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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