1 What: /sys/class/hwmon/hwmonX/name
4 This should be a short, lowercase string, not containing
5 whitespace, dashes, or the wildcard character '*'.
6 This attribute represents the chip name. It is the only
8 I2C devices get this attribute created automatically.
12 What: /sys/class/hwmon/hwmonX/label
14 A descriptive label that allows to uniquely identify a
15 device within the system.
16 The contents of the label are free-form.
20 What: /sys/class/hwmon/hwmonX/update_interval
22 The interval at which the chip will update readings.
27 Some devices have a variable update rate or interval.
28 This attribute can be used to change it to the desired value.
30 What: /sys/class/hwmon/hwmonX/inY_min
38 What: /sys/class/hwmon/hwmonX/inY_lcrit
40 Voltage critical min value.
46 If voltage drops to or below this limit, the system may
47 take drastic action such as power down or reset. At the very
48 least, it should report a fault.
50 What: /sys/class/hwmon/hwmonX/inY_max
58 What: /sys/class/hwmon/hwmonX/inY_crit
60 Voltage critical max value.
66 If voltage reaches or exceeds this limit, the system may
67 take drastic action such as power down or reset. At the very
68 least, it should report a fault.
70 What: /sys/class/hwmon/hwmonX/inY_input
78 Voltage measured on the chip pin.
80 Actual voltage depends on the scaling resistors on the
81 motherboard, as recommended in the chip datasheet.
83 This varies by chip and by motherboard.
84 Because of this variation, values are generally NOT scaled
85 by the chip driver, and must be done by the application.
86 However, some drivers (notably lm87 and via686a)
87 do scale, because of internal resistors built into a chip.
88 These drivers will output the actual voltage. Rule of
89 thumb: drivers should report the voltage values at the
92 What: /sys/class/hwmon/hwmonX/inY_average
100 What: /sys/class/hwmon/hwmonX/inY_lowest
102 Historical minimum voltage
108 What: /sys/class/hwmon/hwmonX/inY_highest
110 Historical maximum voltage
116 What: /sys/class/hwmon/hwmonX/inY_reset_history
118 Reset inX_lowest and inX_highest
122 What: /sys/class/hwmon/hwmonX/in_reset_history
124 Reset inX_lowest and inX_highest for all sensors
128 What: /sys/class/hwmon/hwmonX/inY_label
130 Suggested voltage channel label.
134 Should only be created if the driver has hints about what
135 this voltage channel is being used for, and user-space
136 doesn't. In all other cases, the label is provided by
141 What: /sys/class/hwmon/hwmonX/inY_enable
143 Enable or disable the sensors.
145 When disabled the sensor read will return -ENODATA.
152 What: /sys/class/hwmon/hwmonX/cpuY_vid
154 CPU core reference voltage.
162 What: /sys/class/hwmon/hwmonX/vrm
164 Voltage Regulator Module version number.
166 RW (but changing it should no more be necessary)
168 Originally the VRM standard version multiplied by 10, but now
169 an arbitrary number, as not all standards have a version
172 Affects the way the driver calculates the CPU core reference
173 voltage from the vid pins.
175 What: /sys/class/hwmon/hwmonX/inY_rated_min
177 Minimum rated voltage.
183 What: /sys/class/hwmon/hwmonX/inY_rated_max
185 Maximum rated voltage.
191 What: /sys/class/hwmon/hwmonX/fanY_min
195 Unit: revolution/min (RPM)
199 What: /sys/class/hwmon/hwmonX/fanY_max
203 Unit: revolution/min (RPM)
205 Only rarely supported by the hardware.
208 What: /sys/class/hwmon/hwmonX/fanY_input
212 Unit: revolution/min (RPM)
216 What: /sys/class/hwmon/hwmonX/fanY_div
220 Integer value in powers of two (1, 2, 4, 8, 16, 32, 64, 128).
224 Some chips only support values 1, 2, 4 and 8.
225 Note that this is actually an internal clock divisor, which
226 affects the measurable speed range, not the read value.
228 What: /sys/class/hwmon/hwmonX/fanY_pulses
230 Number of tachometer pulses per fan revolution.
232 Integer value, typically between 1 and 4.
236 This value is a characteristic of the fan connected to the
237 device's input, so it has to be set in accordance with the fan
240 Should only be created if the chip has a register to configure
241 the number of pulses. In the absence of such a register (and
242 thus attribute) the value assumed by all devices is 2 pulses
245 What: /sys/class/hwmon/hwmonX/fanY_target
249 Unit: revolution/min (RPM)
253 Only makes sense if the chip supports closed-loop fan speed
254 control based on the measured fan speed.
256 What: /sys/class/hwmon/hwmonX/fanY_label
258 Suggested fan channel label.
262 Should only be created if the driver has hints about what
263 this fan channel is being used for, and user-space doesn't.
264 In all other cases, the label is provided by user-space.
268 What: /sys/class/hwmon/hwmonX/fanY_enable
270 Enable or disable the sensors.
272 When disabled the sensor read will return -ENODATA.
279 What: /sys/class/hwmon/hwmonX/fanY_fault
281 Reports if a fan has reported failure.
288 What: /sys/class/hwmon/hwmonX/pwmY
290 Pulse width modulation fan control.
292 Integer value in the range 0 to 255
298 What: /sys/class/hwmon/hwmonX/pwmY_enable
300 Fan speed control method:
302 - 0: no fan speed control (i.e. fan at full speed)
303 - 1: manual fan speed control enabled (using `pwmY`)
304 - 2+: automatic fan speed control enabled
306 Check individual chip documentation files for automatic mode
311 What: /sys/class/hwmon/hwmonX/pwmY_mode
313 - 0: DC mode (direct current)
314 - 1: PWM mode (pulse-width modulation)
318 What: /sys/class/hwmon/hwmonX/pwmY_freq
320 Base PWM frequency in Hz.
322 Only possibly available when pwmN_mode is PWM, but not always
327 What: /sys/class/hwmon/hwmonX/pwmY_auto_channels_temp
329 Select which temperature channels affect this PWM output in
332 Bitfield, 1 is temp1, 2 is temp2, 4 is temp3 etc...
333 Which values are possible depend on the chip used.
337 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_pwm
338 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_temp
339 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_temp_hyst
341 Define the PWM vs temperature curve.
343 Number of trip points is chip-dependent. Use this for chips
344 which associate trip points to PWM output channels.
348 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_pwm
349 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_temp
350 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_temp_hyst
352 Define the PWM vs temperature curve.
354 Number of trip points is chip-dependent. Use this for chips
355 which associate trip points to temperature channels.
359 What: /sys/class/hwmon/hwmonX/tempY_type
361 Sensor type selection.
367 - 1: CPU embedded diode
374 Not all types are supported by all chips
376 What: /sys/class/hwmon/hwmonX/tempY_max
378 Temperature max value.
380 Unit: millidegree Celsius (or millivolt, see below)
384 What: /sys/class/hwmon/hwmonX/tempY_min
386 Temperature min value.
388 Unit: millidegree Celsius
392 What: /sys/class/hwmon/hwmonX/tempY_max_hyst
394 Temperature hysteresis value for max limit.
396 Unit: millidegree Celsius
398 Must be reported as an absolute temperature, NOT a delta
403 What: /sys/class/hwmon/hwmonX/tempY_min_hyst
405 Temperature hysteresis value for min limit.
406 Unit: millidegree Celsius
408 Must be reported as an absolute temperature, NOT a delta
413 What: /sys/class/hwmon/hwmonX/tempY_input
415 Temperature input value.
417 Unit: millidegree Celsius
421 What: /sys/class/hwmon/hwmonX/tempY_crit
423 Temperature critical max value, typically greater than
424 corresponding temp_max values.
426 Unit: millidegree Celsius
430 What: /sys/class/hwmon/hwmonX/tempY_crit_alarm
432 Critical high temperature alarm flag.
435 - 1: temperature has reached tempY_crit
439 Contrary to regular alarm flags which clear themselves
440 automatically when read, this one sticks until cleared by
441 the user. This is done by writing 0 to the file. Writing
442 other values is unsupported.
444 What: /sys/class/hwmon/hwmonX/tempY_crit_hyst
446 Temperature hysteresis value for critical limit.
448 Unit: millidegree Celsius
450 Must be reported as an absolute temperature, NOT a delta
451 from the critical value.
455 What: /sys/class/hwmon/hwmonX/tempY_emergency
457 Temperature emergency max value, for chips supporting more than
458 two upper temperature limits. Must be equal or greater than
459 corresponding temp_crit values.
461 Unit: millidegree Celsius
465 What: /sys/class/hwmon/hwmonX/tempY_emergency_hyst
467 Temperature hysteresis value for emergency limit.
469 Unit: millidegree Celsius
471 Must be reported as an absolute temperature, NOT a delta
472 from the emergency value.
476 What: /sys/class/hwmon/hwmonX/tempY_lcrit
478 Temperature critical min value, typically lower than
479 corresponding temp_min values.
481 Unit: millidegree Celsius
485 What: /sys/class/hwmon/hwmonX/tempY_lcrit_hyst
487 Temperature hysteresis value for critical min limit.
489 Unit: millidegree Celsius
491 Must be reported as an absolute temperature, NOT a delta
492 from the critical min value.
496 What: /sys/class/hwmon/hwmonX/tempY_offset
498 Temperature offset which is added to the temperature reading
501 Unit: millidegree Celsius
505 What: /sys/class/hwmon/hwmonX/tempY_label
507 Suggested temperature channel label.
511 Should only be created if the driver has hints about what
512 this temperature channel is being used for, and user-space
513 doesn't. In all other cases, the label is provided by
518 What: /sys/class/hwmon/hwmonX/tempY_lowest
520 Historical minimum temperature
522 Unit: millidegree Celsius
526 What: /sys/class/hwmon/hwmonX/tempY_highest
528 Historical maximum temperature
530 Unit: millidegree Celsius
534 What: /sys/class/hwmon/hwmonX/tempY_reset_history
536 Reset temp_lowest and temp_highest
540 What: /sys/class/hwmon/hwmonX/temp_reset_history
542 Reset temp_lowest and temp_highest for all sensors
546 What: /sys/class/hwmon/hwmonX/tempY_enable
548 Enable or disable the sensors.
550 When disabled the sensor read will return -ENODATA.
557 What: /sys/class/hwmon/hwmonX/tempY_rated_min
559 Minimum rated temperature.
561 Unit: millidegree Celsius
565 What: /sys/class/hwmon/hwmonX/tempY_rated_max
567 Maximum rated temperature.
569 Unit: millidegree Celsius
573 What: /sys/class/hwmon/hwmonX/currY_max
581 What: /sys/class/hwmon/hwmonX/currY_min
589 What: /sys/class/hwmon/hwmonX/currY_lcrit
591 Current critical low value
597 What: /sys/class/hwmon/hwmonX/currY_crit
599 Current critical high value.
605 What: /sys/class/hwmon/hwmonX/currY_input
613 What: /sys/class/hwmon/hwmonX/currY_average
621 What: /sys/class/hwmon/hwmonX/currY_lowest
623 Historical minimum current
629 What: /sys/class/hwmon/hwmonX/currY_highest
631 Historical maximum current
635 What: /sys/class/hwmon/hwmonX/currY_reset_history
637 Reset currX_lowest and currX_highest
641 What: /sys/class/hwmon/hwmonX/curr_reset_history
643 Reset currX_lowest and currX_highest for all sensors
647 What: /sys/class/hwmon/hwmonX/currY_enable
649 Enable or disable the sensors.
651 When disabled the sensor read will return -ENODATA.
658 What: /sys/class/hwmon/hwmonX/currY_rated_min
660 Minimum rated current.
666 What: /sys/class/hwmon/hwmonX/currY_rated_max
668 Maximum rated current.
674 What: /sys/class/hwmon/hwmonX/powerY_average
682 What: /sys/class/hwmon/hwmonX/powerY_average_interval
684 Power use averaging interval. A poll
685 notification is sent to this file if the
686 hardware changes the averaging interval.
692 What: /sys/class/hwmon/hwmonX/powerY_average_interval_max
694 Maximum power use averaging interval
700 What: /sys/class/hwmon/hwmonX/powerY_average_interval_min
702 Minimum power use averaging interval
708 What: /sys/class/hwmon/hwmonX/powerY_average_highest
710 Historical average maximum power use
716 What: /sys/class/hwmon/hwmonX/powerY_average_lowest
718 Historical average minimum power use
724 What: /sys/class/hwmon/hwmonX/powerY_average_max
726 A poll notification is sent to
727 `powerY_average` when power use
728 rises above this value.
734 What: /sys/class/hwmon/hwmonX/powerY_average_min
736 A poll notification is sent to
737 `powerY_average` when power use
738 sinks below this value.
744 What: /sys/class/hwmon/hwmonX/powerY_input
746 Instantaneous power use
752 What: /sys/class/hwmon/hwmonX/powerY_input_highest
754 Historical maximum power use
760 What: /sys/class/hwmon/hwmonX/powerY_input_lowest
762 Historical minimum power use
768 What: /sys/class/hwmon/hwmonX/powerY_reset_history
770 Reset input_highest, input_lowest,
771 average_highest and average_lowest.
775 What: /sys/class/hwmon/hwmonX/powerY_accuracy
777 Accuracy of the power meter.
783 What: /sys/class/hwmon/hwmonX/powerY_cap
785 If power use rises above this limit, the
786 system should take action to reduce power use.
787 A poll notification is sent to this file if the
788 cap is changed by the hardware. The `*_cap`
789 files only appear if the cap is known to be
790 enforced by hardware.
796 What: /sys/class/hwmon/hwmonX/powerY_cap_hyst
798 Margin of hysteresis built around capping and
805 What: /sys/class/hwmon/hwmonX/powerY_cap_max
807 Maximum cap that can be set.
813 What: /sys/class/hwmon/hwmonX/powerY_cap_min
815 Minimum cap that can be set.
821 What: /sys/class/hwmon/hwmonX/powerY_max
829 What: /sys/class/hwmon/hwmonX/powerY_crit
831 Critical maximum power.
833 If power rises to or above this limit, the
834 system is expected take drastic action to reduce
835 power consumption, such as a system shutdown or
836 a forced powerdown of some devices.
842 What: /sys/class/hwmon/hwmonX/powerY_enable
844 Enable or disable the sensors.
846 When disabled the sensor read will return
854 What: /sys/class/hwmon/hwmonX/powerY_rated_min
862 What: /sys/class/hwmon/hwmonX/powerY_rated_max
870 What: /sys/class/hwmon/hwmonX/energyY_input
872 Cumulative energy use
878 What: /sys/class/hwmon/hwmonX/energyY_enable
880 Enable or disable the sensors.
882 When disabled the sensor read will return
890 What: /sys/class/hwmon/hwmonX/humidityY_input
894 Unit: milli-percent (per cent mille, pcm)
899 What: /sys/class/hwmon/hwmonX/humidityY_enable
901 Enable or disable the sensors
903 When disabled the sensor read will return
911 What: /sys/class/hwmon/hwmonX/humidityY_rated_min
913 Minimum rated humidity.
915 Unit: milli-percent (per cent mille, pcm)
919 What: /sys/class/hwmon/hwmonX/humidityY_rated_max
921 Maximum rated humidity.
923 Unit: milli-percent (per cent mille, pcm)
928 What: /sys/class/hwmon/hwmonX/intrusionY_alarm
930 Chassis intrusion detection
933 - 1: intrusion detected
937 Contrary to regular alarm flags which clear themselves
938 automatically when read, this one sticks until cleared by
939 the user. This is done by writing 0 to the file. Writing
940 other values is unsupported.
942 What: /sys/class/hwmon/hwmonX/intrusionY_beep
944 Chassis intrusion beep
951 What: /sys/class/hwmon/hwmonX/device/pec
953 PEC support on I2C devices