xref: /freebsd/share/man/man9/devclass.9 (revision 5b56413d04e608379c9a306373554a8e4d321bc0)
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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.
49All instances with the same name are treated as being the same.
50.Pp
51When no specific unit number is needed,
52.Vt DEVICE_UNIT_ANY
53is used.
54.Sh SEE ALSO
55.Xr devclass_add_driver 9 ,
56.Xr devclass_delete_driver 9 ,
57.Xr devclass_find 9 ,
58.Xr devclass_find_driver 9 ,
59.Xr devclass_get_device 9 ,
60.Xr devclass_get_devices 9 ,
61.Xr devclass_get_maxunit 9 ,
62.Xr devclass_get_name 9 ,
63.Xr devclass_get_softc 9 ,
64.Xr device 9 ,
65.Xr driver 9
66.Sh AUTHORS
67This manual page was written by
68.An Doug Rabson .
69