xref: /dragonfly/sys/kern/device_if.m (revision 2cd2d2b5) 
1#
2# Copyright (c) 1998 Doug Rabson
3# All rights reserved.
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions
7# are met:
8# 1. Redistributions of source code must retain the above copyright
9#    notice, this list of conditions and the following disclaimer.
10# 2. Redistributions in binary form must reproduce the above copyright
11#    notice, this list of conditions and the following disclaimer in the
12#    documentation and/or other materials provided with the distribution.
13#
14# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24# SUCH DAMAGE.
25#
26# $FreeBSD: src/sys/kern/device_if.m,v 1.7.2.1 2001/07/24 09:49:41 dd Exp $
27# $DragonFly: src/sys/kern/device_if.m,v 1.3 2003/11/17 00:54:40 asmodai Exp $
28#
29
30#include <sys/bus.h>
31
32INTERFACE device;
33
34#
35# Default implementations of some methods.
36#
37CODE {
38	static int null_shutdown(device_t dev)
39	{
40	    return 0;
41	}
42
43	static int null_suspend(device_t dev)
44	{
45	    return 0;
46	}
47
48	static int null_resume(device_t dev)
49	{
50	    return 0;
51	}
52};
53
54#
55# Probe to see if the device is present.  Return 0 if the device exists,
56# ENXIO if it cannot be found. If some other error happens during the
57# probe (such as a memory allocation failure), an appropriate error code
58# should be returned. For cases where more than one driver matches a
59# device, a priority value can be returned.  In this case, success codes
60# are values less than or equal to zero with the highest value representing
61# the best match.  Failure codes are represented by positive values and
62# the regular unix error codes should be used for the purpose.
63
64# If a driver returns a success code which is less than zero, it must
65# not assume that it will be the same driver which is attached to the
66# device. In particular, it must not assume that any values stored in
67# the softc structure will be available for its attach method and any
68# resources allocated during probe must be released and re-allocated
69# if the attach method is called.  If a success code of zero is
70# returned, the driver can assume that it will be the one attached.
71#
72# Devices which implement busses should use this method to probe for
73# the existence of devices attached to the bus and add them as
74# children.  If this is combined with the use of bus_generic_attach,
75# the child devices will be automatically probed and attached.
76#
77METHOD int probe {
78	device_t dev;
79};
80
81#
82# Called by a parent bus to add new devices to the bus.
83#
84STATICMETHOD void identify {
85	driver_t *driver;
86	device_t parent;
87};
88
89#
90# Attach a device to the system.  The probe method will have been
91# called and will have indicated that the device exists.  This routine
92# should initialise the hardware and allocate other system resources.
93# Returns 0 on success.
94#
95METHOD int attach {
96	device_t dev;
97};
98
99#
100# Detach a device.  This can be called if the user is replacing the
101# driver software or if a device is about to be physically removed
102# from the system (e.g. for pccard devices).  Returns 0 on success.
103#
104METHOD int detach {
105	device_t dev;
106};
107
108#
109# This is called during system shutdown to allow the driver to put the
110# hardware into a consistent state for rebooting the computer.
111#
112METHOD int shutdown {
113	device_t dev;
114} DEFAULT null_shutdown;
115
116#
117# This is called by the power-management subsystem when a suspend has been
118# requested by the user or by some automatic mechanism.  This gives
119# drivers a chance to veto the suspend or save their configuration before
120# power is removed.
121#
122METHOD int suspend {
123	device_t dev;
124} DEFAULT null_suspend;
125
126METHOD int resume {
127	device_t dev;
128} DEFAULT null_resume;
129