.\"	$OpenBSD: lm.4,v 1.26 2019/12/17 01:34:59 mortimer Exp $
.\"	$NetBSD: lm.4,v 1.11 2001/09/22 01:22:49 wiz Exp $
.\"
.\" Copyright (c) 2000 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Bill Squier.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd $Mdocdate: December 17 2019 $
.Dt LM 4
.Os
.Sh NAME
.Nm lm
.Nd National Semiconductor LM78/79/81 temperature, voltage, and fan sensor
.Sh SYNOPSIS
.Cd "lm0 at isa? port 0x290"
.Cd "lm1 at isa? port 0x280"
.Cd "lm2 at isa? port 0x310"
.\" .Cd "lm0 at pnpbios0"
.Cd "lm* at iic?"
.Cd "lm* at wbsio?"
.Sh DESCRIPTION
The
.Nm
driver provides support for the
National Semiconductor LM78/79/81
hardware monitors and register compatible chips to be used with the
.Xr sysctl 8
interface.
.Pp
The original LM78 hardware monitor supports 11 sensors:
.Bl -column "Sensor" "Units" "Typical" -offset indent
.It Sy "Sensor" Ta Sy "Units" Ta Sy "Typical Use"
.It Li "IN0" Ta "uV DC" Ta "Core voltage"
.It Li "IN1" Ta "uV DC" Ta "Unknown"
.It Li "IN2" Ta "uV DC" Ta "+3.3V"
.It Li "IN3" Ta "uV DC" Ta "+5V"
.It Li "IN4" Ta "uV DC" Ta "+12V"
.It Li "IN5" Ta "uV DC" Ta "-12V"
.It Li "IN6" Ta "uV DC" Ta "-5V"
.It Li "Temp" Ta "uK" Ta "Motherboard Temperature"
.It Li "Fan0" Ta "RPM" Ta "Fan"
.It Li "Fan1" Ta "RPM" Ta "Chassis Fan"
.It Li "Fan2" Ta "RPM" Ta "Fan"
.El
.Pp
For other devices, sensors' names and numbers will be different.
.Sh HARDWARE
Chips supported by the
.Nm
driver include:
.Pp
.Bl -dash -offset indent -compact
.It
ASUS AS99127F
.It
National Semiconductor LM78 and LM78-J
.It
National Semiconductor LM79
.It
National Semiconductor LM81
.It
Nuvoton NCT6775F, NCT6776F, NCT6779D, NCT6791D, NCT6792D, NCT6793D, NCT6795D
.It
Winbond W83627HF, W83627THF, W83637HF and W83697HF
.It
Winbond W83627DHG, W83627UHG and W83627EHF
.It
Winbond W83781D, W83782D and W83783S
.It
Winbond W83791D, W83791SD and W83792D
.El
.Pp
Some devices can attach to both
.Xr iic 4
and
.Xr isa 4 ;
others can only attach to either one or the other.
If the
.Nm
driver detects a device attaching to both
.Xr iic 4
and
.Xr isa 4 ,
it will detach the device from
.Xr iic 4 .
.Sh SEE ALSO
.Xr iic 4 ,
.Xr isa 4 ,
.Xr wbsio 4 ,
.Xr sensorsd 8 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Nx 1.5 ;
.Ox
support was added in
.Ox 3.4 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Bill Squier
and ported to
.Ox 3.4
by
.An Alexander Yurchenko Aq Mt grange@openbsd.org .
The driver was largely rewritten for
.Ox 3.9
by
.An Mark Kettenis Aq Mt kettenis@openbsd.org .
.Sh CAVEATS
Some vendors connect these chips to non-standard thermal diodes and
resistors.
This will result in bogus sensor values.
.Sh BUGS
Interrupt support is unimplemented.
.Pp
There are currently no known pnpbios IDs assigned to LM chips.
.Pp
This driver attaches to the Winbond W83791SD chip even though that
chip does not have any sensors.