xref: /freebsd/share/man/man9/devclass.9 (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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29.Dd June 16, 1998
30.Dt DEVCLASS 9
31.Os
32.Sh NAME
33.Nm devclass
34.Nd object representing a class of devices
35.Sh SYNOPSIS
36.Vt typedef struct devclass *devclass_t ;
37.Sh DESCRIPTION
38The
39.Vt devclass
40object has two main functions in the system.
41The first is to manage
42the allocation of unit numbers for device instances and the second is
43to hold the list of device drivers for a particular bus type.
44Each
45.Vt devclass
46has a name and there cannot be two devclasses with the same name.
47This ensures that unique unit numbers are allocated to device
48instances.
49.Pp
50Beware that this means
51.Vt devclass
52must be the same for different bus attachments of the same device driver.
53.Sh SEE ALSO
54.Xr devclass_add_driver 9 ,
55.Xr devclass_delete_driver 9 ,
56.Xr devclass_find 9 ,
57.Xr devclass_find_driver 9 ,
58.Xr devclass_get_device 9 ,
59.Xr devclass_get_devices 9 ,
60.Xr devclass_get_maxunit 9 ,
61.Xr devclass_get_name 9 ,
62.Xr devclass_get_softc 9 ,
63.Xr device 9 ,
64.Xr driver 9
65.Sh AUTHORS
66This manual page was written by
67.An Doug Rabson .
68