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.\" Copyright (c) 2020 Andriy Gapon <avg@FreeBSD.org>
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.Dd November 6, 2021
.Dt MAX44009 4
.Os
.Sh NAME
.Nm max44009
.Nd driver for MAX44009 Ambient Light Sensor
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device max44009"
.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
max44009_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver reports illuminance data from MAX44009 Ambient Light Sensor.
.Pp
The
.Nm
driver reports data via
.Xr sysctl 8
entry in the device's node in the
.Xr sysctl 8
tree:
.Bl -tag -width illuminance
.It Va illuminance
The illuminance, in lux units.
.El
.Pp
On an
.Xr FDT 4
based system the following properties must be set:
.Bl -tag -width "compatible"
.It Va compatible
Must be set to
.Qq maxim,max44009 .
.It Va reg
The I2C address of
.Nm
which can be either 0x4a or 0x4b.
.El
.Sh SEE ALSO
.Xr fdt 4 ,
.Xr iicbus 4 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
driver and this manual page was written by
.An Andriy Gapon Aq Mt avg@FreeBSD.org .
.Sh BUGS
The
.Nm
driver does not support illuminance thresholds and the corresponding
interrupt.