ENVSYS(4)               NetBSD Kernel Interfaces Manual              ENVSYS(4)

NAME
     envsys -- Environmental Systems framework (version 2)

SYNOPSIS
     #include <sys/envsys.h>

DESCRIPTION
     The envsys framework provides support to handle hardware monitor devices.
     Hardware monitoring chips are able to report values from different types
     of sensors.

     The envsys framework consists of two parts:

           1.   the userland part, to receive the current sensor data and to
                set some properties on sensors: envstat(8).
           2.   The kernel part that is able to talk to the drivers providing
                sensor data: sysmon_envsys(9).

     The envsys framework uses proplib(3) for communication between kernel and
     user space.  The following ioctl(2) types are available:

     ENVSYS_GETDICTIONARY (prop_dictionary_t)

         This ioctl(2) is used to receive the global dictionary that is being
         used in the kernel by the sysmon_envsys(9) framework.  It will con-
         tain an array of dictionaries per device and one dictionary per sen-
         sor plus another special dictionary that contains the properties for
         a device.  Each sensor dictionary will have their own characteristics
         and values.

         The following XML property list represents a virtual device
         ``device0'' with one sensor ``sensor0'' and all available properties
         set on it, plus another sensor for the ``device-properties'' dictio-
         nary (which contains specific properties for a device):

         <key>device0</key>
         <array>
                 <dict>
                         <key>allow-rfact</key>
                         <true/>
                         <key>avg-value</key>
                         <integer>36400</integer>
                         <key>battery-capacity</key>
                         <string>NORMAL</string>
                         <key>critical-capacity</key>
                         <integer>21417</integer>
                         <key>critical-max</key>
                         <integer>343150000</integer>
                         <key>critical-min</key>
                         <integer>288150000</integer>
                         <key>cur-value</key>
                         <integer>406000</integer>
                         <key>description</key>
                         <string>CPU Temp</string>
                         <string>index</string>
                         <string>sensor0</string>
                         <key>max-value</key>
                         <integer>3894000</integer>
                         <key>min-value</key>
                         <integer>2894000</integer>
                         <key>monitoring-state-critical</key>
                         <true/>
                         <key>monitoring-state-critover</key>
                         <true/>
                         <key>monitoring-state-critunder</key>
                         <true/>
                         <key>monitoring-state-state-changed</key>
                         <true/>
                         <key>monitoring-state-warnover</key>
                         <true/>
                         <key>monitoring-state-warnunder</key>
                         <true/>
                         <key>monitoring-supported</key>
                         <true/>
                         <key>state</key>
                         <string>valid</string>
                         <key>type</key>
                         <string>Ampere hour</string>
                         <key>want-percentage</key>
                         <true/>
                 </dict>
                 <dict>
                         <key>device-properties</key>
                         <dict>
                                 <key>refresh-timeout</key>
                                 <integer>0xa</integer>
                         </dict>
                 </dict>
         </array>

         Let's explain some more about those objects:

         allow-rfact                       Set to true mean that the sensor is
                                           able to change the resistor factor,
                                           only used in Voltage sensors.

         avg-value                         Current average value in the sen-
                                           sor.

         battery-capacity                  Current capacity state for a bat-
                                           tery capacity sensor.

         critical-capacity                 Critical capacity set previously by
                                           the ENVSYS_SETDICTIONARY ioctl(2).
                                           Only available on sensors with the
                                           want-percentage object enabled.

         critical-max                      Critical max limit set previously
                                           by the ENVSYS_SETDICTIONARY
                                           ioctl(2).

         critical-min                      Critical min limit set previously
                                           by the ENVSYS_SETDICTIONARY
                                           ioctl(2).

         cur-value                         Current value in the sensor.

         description                       Description of the sensor.

         index                             Index position of the sensor.

         max-value                         Current max value in the sensor.

         min-value                         Current min value in the sensor.

         monitoring-state-critical         If true, the driver has enabled the
                                           flag to monitor a critical state.

         monitoring-state-critical-over    If true, the driver has enabled the
                                           flag to monitor a critical over
                                           state.

         monitoring-state-critical-under   If true, the driver has enabled the
                                           flag to monitor a critical under
                                           state.

         monitoring-state-state-changed    If true, the driver has enabled the
                                           flag to monitor for state changes
                                           in a drive or Battery state sensor.

         monitoring-state-warning-over     If true, the driver has enabled the
                                           flag to monitor a warning over
                                           state.

         monitoring-state-warning-under    If true, the driver has enabled the
                                           flag to monitor a warning under
                                           state.

         monitoring-supported              If true, critical capacity/max/min
                                           limits may be set by the
                                           ENVSYS_SETDICTIONARY ioctl(2).

         state                             Current state in the sensor.

         type                              Type of unit in the sensor.

         want-percentage                   If true, max-value and cur-value
                                           are valid and a percentage may be
                                           computed from them.

     ENVSYS_REMOVEPROPS (prop_dictionary_t)

         This ioctl(2) is used to remove all properties that are currently set
         via the ENVSYS_SETDICTIONARY ioctl.  The values will be set to
         defaults, the ones that the driver uses.

         Only one object is allowed on this dictionary:

                       <key>envsys-remove-props</key>
                       <true/>

         It is a boolean object and must be set to true to be effective.

     ENVSYS_SETDICTIONARY (prop_dictionary_t)

         This ioctl(2) is used to send a dictionary with new properties that
         should be processed by the envsys framework.  Only a set of prede-
         fined keywords are recognized by the kernel part.  The following is
         the property list representation of a dictionary with all recognized
         and required keywords that a sensor understands:

         <dict>
                 <key>description</key>
                 <string>cpu temp</string>
                 <key>rfact</key>
                 <integer>56000</integer>
                 <key>critical-capacity</key>
                 <integer>10</integer>
                 <key>critical-max</key>
                 <integer>3400</integer>
                 <key>critical-min</key>
                 <integer>2800</integer>
         </dict>

         Also if some properties in a device need to be changed, the
         ``device-properties'' dictionary must be used.  At this moment only
         the ``refresh-timeout'' property is understood.  This has the follow-
         ing structure:

         <dict>
                 <key>device-properties</key>
                 <dict>
                         <key>refresh-timeout</key>
                         <integer>0xa</integer>
                 </dict>
         </dict>

         A dictionary sent to the kernel with this ioctl(2) should have the
         following structure:

         <dict>
                 <key>device_name</key>
                 <array>
                         <dict>
                                 <key>index</key>
                                 <string>sensor0</string>
                                 <key>description</key>
                                 <string>cpu temp</string>
                                 ...
                                 Another property for this sensor
                                 ...
                         </dict>
                         ...
                         Another dictionary for device-properties or sensor
                         ...
                 </array>
                 ...
                 Another device as above
                 ...
         </dict>

         The named device will be an array and will contain dictionaries, any
         dictionary needs to have the index object specifying the sensor that
         is required for the new properties.

         If an unknown object was sent with the dictionary, EINVAL will be
         returned, or if the sensor does not support changing rfact (voltage
         sensors) or critical/capacity limits, ENOTSUP will be returned.

NOTES
     When setting a critical max or min limit with the ENVSYS_SETDICTIONARY
     ioctl(2), the user must be aware that sysmon_envsys(9) expects to have a
     proper unit, so the value must be converted.  Please see sysmon_envsys(9)
     for more information.

     Also when setting a critical capacity limit, the formula to send a proper
     value to sysmon_envsys(9) is the following: value = (value / 100) * max
     value.  The max value is available in the sensor's dictionary.

EXAMPLES
     The following example shows how to change the description of `sensor0' in
     the `aiboost0' device with the ENVSYS_SETDICTIONARY ioctl(2):

     int
     main(void)
     {
             prop_dictionary_t global_dict, sensor_dict;
             prop_array_t array;
             prop_object_t obj;
             int fd;

             global_dict = prop_dictionary_create();
             sensor_dict = prop_dictionary_create();
             array = prop_array_create();

             if (!prop_dictionary_set(global_dict, "aiboost0", array))
                     err(EINVAL, "prop_dictionary_set global");

             obj = prop_string_create_cstring_nocopy("sensor0");
             if (obj == NULL ||
                 !prop_dictionary_set(dict, "index", obj))
                     err(EINVAL, "sensor index");

             prop_object_release(obj);

             /* new description */
             obj = prop_string_create_cstring_nocopy("CPU temp");
             if (obj == NULL ||
                 !prop_dictionary_set(dict, "description", obj))
                     err(EINVAL, "new description");

             prop_object_release(obj);

             if (!prop_array_add(array, sensor_dict))
                     err(EINVAL, "prop_array_add");

             if ((fd = open(_DEV_SYSMON, O_RDWR)) == -1)
                     err(EXIT_FAILURE, "open")

             /* we are done, send the dictionary */
             error = prop_dictionary_send_ioctl(global_dict,
                                                fd,
                                                ENVSYS_SETDICTIONARY);
             prop_object_release(array);
             prop_object_release(global_dict);
             (void)close(fd);
             return error;
     }

SEE ALSO
     envstat(8), powerd(8), sysmon_envsys(9)

HISTORY
     The first envsys framework first appeared in NetBSD 1.5.  The envsys 2
     framework first appeared in NetBSD 5.0.

AUTHORS
     The (current) envsys 2 framework was implemented by Juan Romero Pardines.
     Additional input on the design was provided by many NetBSD developers
     around the world.

     The first envsys framework was implemented by Jason R. Thorpe, Tim Right-
     nour, and Bill Squier.

NetBSD 5.0_STABLE              November 13, 2007             NetBSD 5.0_STABLE
