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 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. The driver 83# should check parent->state to determine whether this is an initial 84# identification scan on the bus, or whether it is a rescan. If 85# parent->state == DS_ATTACHED then the identify call is a re-scan. 86# 87# Return 0 on success, 0 on rescan, or an error on the initial scan if no 88# devices were added to the bus. Using generic_bus_identify() will 89# simply call BUS_ADD_CHILD using the driver name. 90# 91# Standard matching devices do not usually have an identify function, whereas 92# busses or any entity which needs to create static device entries under 93# the bus will. 94# 95STATICMETHOD int identify { 96 driver_t *driver; 97 device_t parent; 98}; 99 100# 101# Attach a device to the system. The probe method will have been 102# called and will have indicated that the device exists. This routine 103# should initialise the hardware and allocate other system resources. 104# Returns 0 on success. 105# 106METHOD int attach { 107 device_t dev; 108}; 109 110# 111# Detach a device. This can be called if the user is replacing the 112# driver software or if a device is about to be physically removed 113# from the system (e.g. for pccard devices). Returns 0 on success. 114# 115METHOD int detach { 116 device_t dev; 117}; 118 119# 120# This is called during system shutdown to allow the driver to put the 121# hardware into a consistent state for rebooting the computer. 122# 123METHOD int shutdown { 124 device_t dev; 125} DEFAULT null_shutdown; 126 127# 128# This is called by the power-management subsystem when a suspend has been 129# requested by the user or by some automatic mechanism. This gives 130# drivers a chance to veto the suspend or save their configuration before 131# power is removed. 132# 133METHOD int suspend { 134 device_t dev; 135} DEFAULT null_suspend; 136 137METHOD int resume { 138 device_t dev; 139} DEFAULT null_resume; 140