SWSENSOR(4)						   BSD Kernel Interfaces Manual 					       SWSENSOR(4)

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.

BSD
								  August 27, 2012							       BSD