config root man

.\" Copyright (c) 2011 Henrik Brix Andersen <brix@FreeBSD.org>
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.\" $FreeBSD: release/9.1.0/share/man/man4/man4.i386/glxiic.4 221961 2011-05-15 14:01:23Z brix $
.\"
.Dd May 15, 2011
.Dt GLXIIC 4 i386
.Os
.Sh NAME
.Nm glxiic
.Nd Geode LX CS5536 I2C controller driver
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device pci"
.Cd "device isa"
.Cd "device glxiic"
.Cd "device iicbus"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
glxiic_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver supports the System Management Bus controller of the Geode LX
series CS5536 Companion Device.  The Geode LX is a member of the AMD
Geode family of integrated x86 system chips.
.Pp
Although AMD refers to this device as a System Management Bus (SMBus)
controller, it is really an I2C controller (it lacks SMBus ALERT# and
Alert Response support).
.Pp
The
.Nm
driver supports both I2C master and slave mode.
.Sh SYSCTL VARIABLE
The
.Nm
driver supports the following variable as both
.Xr sysctl 8
and
.Xr loader 8
tunable:
.Bl -tag -width indent
.It Va dev.glxiic.0.timeout
This variable controls the I2C bus timeout in milliseconds.  The
default timeout is 35 milliseconds.  A value of zero disables the
timeout.
.El
.Sh CAVEAT
The
.Nm
driver uses the interrupt line number configured by the board firmware
by default.  If no interrupt line number has been configured by the
board firmware (or to override the interrupt line number configured by
board firmware), place the following line in
.Xr device.hints 5 :
.Bd -ragged -offset indent
hint.glxiic.0.irq="10"
.Ed
.Pp
The interrupt line number must be between 1 and 15.
.Sh SEE ALSO
.Xr iicbus 4 ,
.Xr device.hints 5 ,
.Xr loader.conf 5 ,
.Xr loader 8 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
device driver and manual page first appeared in
.Fx 9.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
device driver and manual page were written by
.An Henrik Brix Andersen Aq brix@FreeBSD.org .