1.\" Copyright (c) 2000 Alexander Langer 2.\" 3.\" All rights reserved. 4.\" 5.\" This program is free software. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 17.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 20.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26.\" 27.\" $FreeBSD: src/share/man/man9/DRIVER_MODULE.9,v 1.1.2.5 2001/12/17 11:30:18 ru Exp $ 28.\" 29.Dd May 31, 2022 30.Dt DRIVER_MODULE 9 31.Os 32.Sh NAME 33.Nm DRIVER_MODULE , 34.Nm DRIVER_MODULE_ORDERED 35.Nd kernel driver declaration macro 36.Sh SYNOPSIS 37.In sys/types.h 38.In sys/bus.h 39.In sys/module.h 40.Fn DRIVER_MODULE name busname "driver_t driver" "devclass_t devclass" "modeventhand_t evh" "void *arg" 41.Fn DRIVER_MODULE_ORDERED name busname "driver_t driver" "devclass_t *devclass" "modeventhand_t evh" "void *arg" "int order" 42.Sh DESCRIPTION 43The 44.Fn DRIVER_MODULE 45macro declares a kernel driver. 46.Fn DRIVER_MODULE 47expands to the real driver declaration, where the phrase 48.Fa name 49is used as the naming prefix for the driver and its functions. 50Note that it is supplied as plain text, and not a 51.Li char 52or 53.Li char * . 54.Pp 55.Fa busname 56is the parent bus of the driver (PCI, ISA, PPBUS and others), e.g.\& 57.Ql pci , 58.Ql isa , 59or 60.Ql ppbus . 61.Pp 62The identifier used in 63.Fn DRIVER_MODULE 64can be different from the driver name. 65Also, the same driver identifier can exist on different busses, 66which is a pretty clean way of making front ends for different cards 67using the same driver on the same or different busses. 68For example, the following is allowed: 69.Pp 70.Fn DRIVER_MODULE foo isa foo_driver foo_devclass NULL NULL ; 71.Pp 72.Fn DRIVER_MODULE foo pci foo_driver foo_devclass NULL NULL ; 73.Pp 74.Fa driver 75is the driver of type 76.Li driver_t , 77which contains the information about the driver and is therefore one of the 78two most important parts of the call to 79.Fn DRIVER_MODULE . 80.Pp 81The 82.Fa devclass 83argument contains the kernel-internal information about the device, 84which will be used within the kernel driver module. 85.Pp 86The 87.Fa evh 88argument is the event handler which is called when the driver (or module) 89is loaded or unloaded (see 90.Xr module 9 ) . 91.Pp 92The 93.Fa arg 94is unused at this time and should be a 95.Dv NULL 96pointer. 97.Pp 98The 99.Fn DRIVER_MODULE_ORDERED 100macro allows a driver to be registered in a specific order. 101This can be useful if a single kernel module contains multiple drivers 102that are inter-dependent. 103The 104.Fa order 105argument should be one of the 106.Xr SYSINIT 9 107initialization ordering constants 108.Pq Dv SI_ORDER_* . 109The default order for a driver module is 110.Dv SI_ORDER_MIDDLE . 111Typically a module will specify an order of 112.Dv SI_ORDER_ANY 113for a single driver to ensure it is registered last. 114.Sh SEE ALSO 115.Xr device 9 , 116.Xr driver 9 , 117.Xr module 9 , 118.Xr SYSINIT 9 119.Sh AUTHORS 120This manual page was written by 121.An Alexander Langer Aq Mt alex@FreeBSD.org . 122