Updated: 2021/Apr/14

SWSENSOR(4)                  Device Drivers Manual                 SWSENSOR(4)

     swsensor - software environmental sensor

     pseudo-device swsensor

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

     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.

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

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

     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.

NetBSD 9.99                      June 1, 2016                      NetBSD 9.99