2 # Copyright (c) 1998 Doug Rabson
5 # Redistribution and use in source and binary forms, with or without
6 # modification, are permitted provided that the following conditions
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.
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
26 # $FreeBSD: src/sys/kern/device_if.m,v 1.7.2.1 2001/07/24 09:49:41 dd Exp $
32 # Default implementations of some methods.
35 static int null_shutdown(device_t dev)
40 static int null_suspend(device_t dev)
45 static int null_resume(device_t dev)
52 # Probe to see if the device is present. Return 0 if the device exists,
53 # ENXIO if it cannot be found. If some other error happens during the
54 # probe (such as a memory allocation failure), an appropriate error code
55 # should be returned. For cases where more than one driver matches a
56 # device, a priority value can be returned. In this case, success codes
57 # are values less than or equal to zero with the highest value representing
58 # the best match. Failure codes are represented by positive values and
59 # the regular unix error codes should be used for the purpose.
61 # If a driver returns a success code which is less than zero, it must
62 # not assume that it will be the same driver which is attached to the
63 # device. In particular, it must not assume that any values stored in
64 # the softc structure will be available for its attach method and any
65 # resources allocated during probe must be released and re-allocated
66 # if the attach method is called. If a success code of zero is
67 # returned, the driver can assume that it will be the one attached.
69 # Devices which implement busses should use this method to probe for
70 # the existence of devices attached to the bus and add them as
71 # children. If this is combined with the use of bus_generic_attach,
72 # the child devices will be automatically probed and attached.
79 # Called by a parent bus to add new devices to the bus.
81 STATICMETHOD void identify {
87 # Attach a device to the system. The probe method will have been
88 # called and will have indicated that the device exists. This routine
89 # should initialise the hardware and allocate other system resources.
90 # Returns 0 on success.
97 # Detach a device. This can be called if the user is replacing the
98 # driver software or if a device is about to be physically removed
99 # from the system (e.g. for pccard devices). Returns 0 on success.
106 # This is called during system shutdown to allow the driver to put the
107 # hardware into a consistent state for rebooting the computer.
109 METHOD int shutdown {
111 } DEFAULT null_shutdown;
114 # This is called by the power-management subsystem when a suspend has been
115 # requested by the user or by some automatic mechanism. This gives
116 # drivers a chance to veto the suspend or save their configuration before
121 } DEFAULT null_suspend;
125 } DEFAULT null_resume;