xref: /freebsd/share/man/man9/devclass.9 (revision 1b6c2589164a3a7b2f62d4c28c2ffa1be860959e)
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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.Dv devclass
42object has two main functions in the system.  The first is to manage
43the allocation of unit numbers for device instances and the second is
44to hold the list of device drivers for a particular bus type.
45Each
46.Dv devclass
47has a name and there cannot be two devclasses with the same name.
48This ensures that unique unit numbers are allocated to device
49instances.
50.Pp
51Beware that this means
52.Dv devclass
53must be the same for different bus attachments of the same device driver.
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 man page was written by
68.An Doug Rabson .
69