1.\" Copyright (c) 2008 Yahoo!, Inc. 2.\" All rights reserved. 3.\" Written by: John Baldwin <jhb@FreeBSD.org> 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.\" 3. Neither the name of the author nor the names of any co-contributors 14.\" may be used to endorse or promote products derived from this software 15.\" without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.Dd August 23, 2008 30.Dt DPMS 4 31.Os 32.Sh NAME 33.Nm dpms 34.Nd VESA BIOS DPMS driver 35.Sh SYNOPSIS 36.Cd "device dpms" 37.Sh DESCRIPTION 38The 39.Nm 40driver uses the VESA BIOS to manage an external display during suspend and 41resume. 42When the machine suspends, 43the 44.Nm 45driver turns the external display off. 46When the machine resumes, 47it restores the display to its state when the driver was first loaded. 48.Sh SEE ALSO 49.Xr acpi_video 4 50.Sh BUGS 51The VESA BIOS DPMS calls do not provide any way to identify a particular 52display or adapter to manipulate. 53As a result, 54this driver may have unexpected results on systems with multiple displays 55and/or adapters. 56