1.\" Copyright (c) 1998 Doug Rabson 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/device_get_state.9,v 1.3.2.5 2001/12/17 11:30:18 ru Exp $ 28.\" 29.Dd June 16, 1998 30.Dt DEVICE_GET_STATE 9 31.Os 32.Sh NAME 33.Nm device_get_state , 34.Nm device_busy , 35.Nm device_unbusy , 36.Nm device_is_alive 37.Nd manipulate device state 38.Sh SYNOPSIS 39.In sys/param.h 40.In sys/bus.h 41.Ft device_state_t 42.Fn device_get_state "device_t dev" 43.Ft void 44.Fn device_busy "device_t dev" 45.Ft void 46.Fn device_unbusy "device_t dev" 47.Ft int 48.Fn device_is_alive "device_t dev" 49.Sh DESCRIPTION 50The current state of a device is accessed by calling 51.Fn device_get_state 52which returns 53.Dv DS_NOTPRESENT , 54.Dv DS_ALIVE , 55.Dv DS_ATTACHED 56or 57.Dv DS_BUSY 58(described in 59.Xr device 9 ) . 60To test see if a device was successfully probed, call 61.Fn device_is_alive 62which simply returns if the state is greater or equal to 63.Dv DS_ALIVE . 64.Pp 65Each device has a busy count which is incremented when 66.Fn device_busy 67is called and decremented when 68.Fn device_unbusy 69is called. Both routines return an error if the device state is less 70than 71.Dv DS_ATTACHED . 72.Pp 73When 74.Fn device_busy 75is called on a device in the 76.Dv DS_ATTACHED 77state, the device changes to the 78.Dv DS_BUSY 79state. 80When 81.Fn device_unbusy 82is called and after decrementing, the busy count for the device is 83zero, the device changes to the 84.Dv DS_ATTACHED 85state. 86.Sh SEE ALSO 87.Xr device 9 88.Sh AUTHORS 89This man page was written by 90.An Doug Rabson . 91