1.\" $NetBSD: acpifan.4,v 1.4 2019/04/11 17:46:32 kamil Exp $ 2.\" 3.\" Copyright (c) 2011 Jukka Ruohonen <jruohonen@iki.fi> 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Neither the name of the author nor the names of any 12.\" contributors may be used to endorse or promote products derived 13.\" from this software without specific prior written permission. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd January 9, 2011 28.Dt ACPIFAN 4 29.Os 30.Sh NAME 31.Nm acpifan 32.Nd ACPI Fan 33.Sh SYNOPSIS 34.Cd "acpifan* at acpi?" 35.Sh DESCRIPTION 36The 37.Nm 38device driver supports fans possibly exposed by the 39.Tn BIOS . 40Even if a system contains only one physical fan, multiple 41.Nm 42instances may be present. 43In such cases each 44.Nm 45typically represents an 46.Xr acpitz 4 47thermal zone, and the combined state of all 48instances reveals the speed of the fan. 49.Pp 50The 51.Nm 52driver does not support controlling the fan. 53The current state (on or off) is made available through the 54.Xr envsys 4 55.Tn API 56and the 57.Xr envstat 8 58command. 59.Sh SEE ALSO 60.Xr acpi 4 , 61.Xr acpitz 4 62.Sh HISTORY 63The 64.Nm 65device driver appeared in 66.Nx 6.0 . 67.Sh AUTHORS 68.An Jukka Ruohonen 69.Aq jruohonen@iki.fi 70.Sh BUGS 71The 72.Nm 73driver does not yet support additional functionality introduced in the 74.Tn ACPI 754.0 specification. 76