xref: /dragonfly/sys/kern/device_if.m (revision f9993810) 
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 1.4 2005/10/28 03:25:57 dillon 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	static int null_quiesce(device_t dev)
54	{
55	    return 0;
56	}
57
58	static void * null_register(device_t dev)
59	{
60		return NULL;
61        }
62};
63
64#
65# Probe to see if the device is present.  Return 0 if the device exists,
66# ENXIO if it cannot be found. If some other error happens during the
67# probe (such as a memory allocation failure), an appropriate error code
68# should be returned. For cases where more than one driver matches a
69# device, a priority value can be returned.  In this case, success codes
70# are values less than or equal to zero with the highest value representing
71# the best match.  Failure codes are represented by positive values and
72# the regular unix error codes should be used for the purpose.
73
74# If a driver returns a success code which is less than zero, it must
75# not assume that it will be the same driver which is attached to the
76# device. In particular, it must not assume that any values stored in
77# the softc structure will be available for its attach method and any
78# resources allocated during probe must be released and re-allocated
79# if the attach method is called.  If a success code of zero is
80# returned, the driver can assume that it will be the one attached.
81#
82# Devices which implement busses should use this method to probe for
83# the existence of devices attached to the bus and add them as
84# children.  If this is combined with the use of bus_generic_attach,
85# the child devices will be automatically probed and attached.
86#
87METHOD int probe {
88	device_t dev;
89};
90
91#
92# Called by a parent bus to add new devices to the bus.  The driver
93# should check parent->state to determine whether this is an initial
94# identification scan on the bus, or whether it is a rescan.  If
95# parent->state == DS_ATTACHED then the identify call is a re-scan.
96#
97# Return 0 on success, 0 on rescan, or an error on the initial scan if no
98# devices were added to the bus.  Using generic_bus_identify() will
99# simply call BUS_ADD_CHILD using the driver name.
100#
101# Standard matching devices do not usually have an identify function, whereas
102# busses or any entity which needs to create static device entries under
103# the bus will.
104#
105STATICMETHOD int identify {
106	driver_t *driver;
107	device_t parent;
108};
109
110#
111# Attach a device to the system.  The probe method will have been
112# called and will have indicated that the device exists.  This routine
113# should initialise the hardware and allocate other system resources.
114# Returns 0 on success.
115#
116METHOD int attach {
117	device_t dev;
118};
119
120#
121# Detach a device.  This can be called if the user is replacing the
122# driver software or if a device is about to be physically removed
123# from the system (e.g. for pccard devices).  Returns 0 on success.
124#
125METHOD int detach {
126	device_t dev;
127};
128
129#
130# This is called during system shutdown to allow the driver to put the
131# hardware into a consistent state for rebooting the computer.
132#
133METHOD int shutdown {
134	device_t dev;
135} DEFAULT null_shutdown;
136
137#
138# This is called by the power-management subsystem when a suspend has been
139# requested by the user or by some automatic mechanism.  This gives
140# drivers a chance to veto the suspend or save their configuration before
141# power is removed.
142#
143METHOD int suspend {
144	device_t dev;
145} DEFAULT null_suspend;
146
147METHOD int resume {
148	device_t dev;
149} DEFAULT null_resume;
150
151#
152# Additions for FreeBSD compat
153#
154METHOD int quiesce {
155	device_t dev;
156} DEFAULT null_quiesce;
157
158METHOD void * register {
159	device_t dev;
160} DEFAULT null_register;
161