NAME

swsensor — software environmental sensor

SYNOPSIS

pseudo-device swsensor

DESCRIPTION

The swsensor driver provides a software environmental sensor that works with sysctl(8) and envstat(8). The driver is intended to be loaded as a kernel module. One can, however, include the swsensor driver directly in a kernel using the configuration from the synopsis. By default, the sensor is of type ENVSYS_UNITS_INTEGER.

The following values can be specified in the modload(8) command when loading the swsensor module to alter the driver's behavior.

Variable Usage

mode

Controls whether or not swsensor provides internally-maintained limits and limit checking

Value Meaning

0

sensor has no internally-maintained limits

1

sensor provides its own internal limit value

2

sensor maintains an internal adjustable limit and performs its own comparison between the sensor's limit and its current value

limit

The initial alarm limit value, if limit emulation is selected (i.e., if mode is set to 1 or 2)

value_max

value_min

The maximum and minimum values. The corresponding ENVSYS_FVALID_MAX and ENVSYS_FVALID_MIN flags are implicitly set.

percentage

This boolean value controls the setting of the ENVSYS_FPERCENT flag.

type

Define the sensor's unit/type. By default, a Temperature sensor is created. Any of the string values from the following table can be specified:

Temperature	Fan	Voltage AC
Voltage DC	Ohms	Watts
Ampere	Watt hour	Ampere hour
Indicator	Integer	Drive
Battery capacity	Battery charge

(Values are case-sensitive, and spaces must be included.)

value

Provide an initial value for the sensor. If this is omitted, the sensor's initial value is set to zero.

For example,

modload -s type=Voltage\ DC swsensor

will create a sensor of type ENVSYS_UNITS_SVOLTS_DC, while

modload -i mode=1 -i limit=50 swsensor

will create a sensor which has an initial, device-provided limit of 50.

The sensor's raw value and state can be manually updated by modifying the sysctl(8) variables “hw.swsensor.cur_value” and “hw.swsensor.state” variables respectively.

SEE ALSO

modctl(2), envstat(8), sysctl(8)

HISTORY

The swsensor driver was written by Paul Goyette and first appeared in NetBSD 6.0.

BUGS

The swsensor driver emulates a device with only a single sensor.

The swsensor driver can only emulate one hardware-managed limit; this is assumed to be the critical-min limit.