1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 1998 Doug Rabson 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd June 16, 1998 32.Dt DEVICE_GET_STATE 9 33.Os 34.Sh NAME 35.Nm device_get_state , 36.Nm device_busy , 37.Nm device_unbusy , 38.Nm device_is_alive 39.Nd manipulate device state 40.Sh SYNOPSIS 41.In sys/param.h 42.In sys/bus.h 43.Ft device_state_t 44.Fn device_get_state "device_t dev" 45.Ft void 46.Fn device_busy "device_t dev" 47.Ft void 48.Fn device_unbusy "device_t dev" 49.Ft int 50.Fn device_is_alive "device_t dev" 51.Sh DESCRIPTION 52The current state of a device is accessed by calling 53.Xr device_get_state 9 54which returns 55.Dv DS_NOTPRESENT , 56.Dv DS_ALIVE , 57.Dv DS_ATTACHED 58or 59.Dv DS_BUSY 60(described in 61.Xr device 9 ) . 62To test see if a device was successfully probed, call 63.Xr device_is_alive 9 64which simply returns if the state is greater or equal to 65.Dv DS_ALIVE . 66.Pp 67Each device has a busy count which is incremented when 68.Xr device_busy 9 69is called and decremented when 70.Xr device_unbusy 9 71is called. Both routines return an error if the device state is less 72than 73.Dv DS_ATTACHED . 74.Pp 75When 76.Xr device_busy 9 77is called on a device in the 78.Dv DS_ATTACHED 79state, the device changes to the 80.Dv DS_BUSY 81state. 82When 83.Xr device_unbusy 9 84is called and after decrementing, the busy count for the device is 85zero, the device changes to the 86.Dv DS_ATTACHED 87state. 88.Sh SEE ALSO 89.Xr device 9 90.Sh AUTHORS 91This man page was written by 92.An Doug Rabson . 93