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/pwmY
281 Pulse width modulation fan control.
283 Integer value in the range 0 to 255
289 What: /sys/class/hwmon/hwmonX/pwmY_enable
291 Fan speed control method:
293 - 0: no fan speed control (i.e. fan at full speed)
294 - 1: manual fan speed control enabled (using `pwmY`)
295 - 2+: automatic fan speed control enabled
297 Check individual chip documentation files for automatic mode
302 What: /sys/class/hwmon/hwmonX/pwmY_mode
304 - 0: DC mode (direct current)
305 - 1: PWM mode (pulse-width modulation)
309 What: /sys/class/hwmon/hwmonX/pwmY_freq
311 Base PWM frequency in Hz.
313 Only possibly available when pwmN_mode is PWM, but not always
318 What: /sys/class/hwmon/hwmonX/pwmY_auto_channels_temp
320 Select which temperature channels affect this PWM output in
323 Bitfield, 1 is temp1, 2 is temp2, 4 is temp3 etc...
324 Which values are possible depend on the chip used.
328 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_pwm
329 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_temp
330 What: /sys/class/hwmon/hwmonX/pwmY_auto_pointZ_temp_hyst
332 Define the PWM vs temperature curve.
334 Number of trip points is chip-dependent. Use this for chips
335 which associate trip points to PWM output channels.
339 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_pwm
340 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_temp
341 What: /sys/class/hwmon/hwmonX/tempY_auto_pointZ_temp_hyst
343 Define the PWM vs temperature curve.
345 Number of trip points is chip-dependent. Use this for chips
346 which associate trip points to temperature channels.
350 What: /sys/class/hwmon/hwmonX/tempY_type
352 Sensor type selection.
358 - 1: CPU embedded diode
365 Not all types are supported by all chips
367 What: /sys/class/hwmon/hwmonX/tempY_max
369 Temperature max value.
371 Unit: millidegree Celsius (or millivolt, see below)
375 What: /sys/class/hwmon/hwmonX/tempY_min
377 Temperature min value.
379 Unit: millidegree Celsius
383 What: /sys/class/hwmon/hwmonX/tempY_max_hyst
385 Temperature hysteresis value for max limit.
387 Unit: millidegree Celsius
389 Must be reported as an absolute temperature, NOT a delta
394 What: /sys/class/hwmon/hwmonX/tempY_min_hyst
396 Temperature hysteresis value for min limit.
397 Unit: millidegree Celsius
399 Must be reported as an absolute temperature, NOT a delta
404 What: /sys/class/hwmon/hwmonX/tempY_input
406 Temperature input value.
408 Unit: millidegree Celsius
412 What: /sys/class/hwmon/hwmonX/tempY_crit
414 Temperature critical max value, typically greater than
415 corresponding temp_max values.
417 Unit: millidegree Celsius
421 What: /sys/class/hwmon/hwmonX/tempY_crit_alarm
423 Critical high temperature alarm flag.
426 - 1: temperature has reached tempY_crit
430 Contrary to regular alarm flags which clear themselves
431 automatically when read, this one sticks until cleared by
432 the user. This is done by writing 0 to the file. Writing
433 other values is unsupported.
435 What: /sys/class/hwmon/hwmonX/tempY_crit_hyst
437 Temperature hysteresis value for critical limit.
439 Unit: millidegree Celsius
441 Must be reported as an absolute temperature, NOT a delta
442 from the critical value.
446 What: /sys/class/hwmon/hwmonX/tempY_emergency
448 Temperature emergency max value, for chips supporting more than
449 two upper temperature limits. Must be equal or greater than
450 corresponding temp_crit values.
452 Unit: millidegree Celsius
456 What: /sys/class/hwmon/hwmonX/tempY_emergency_hyst
458 Temperature hysteresis value for emergency limit.
460 Unit: millidegree Celsius
462 Must be reported as an absolute temperature, NOT a delta
463 from the emergency value.
467 What: /sys/class/hwmon/hwmonX/tempY_lcrit
469 Temperature critical min value, typically lower than
470 corresponding temp_min values.
472 Unit: millidegree Celsius
476 What: /sys/class/hwmon/hwmonX/tempY_lcrit_hyst
478 Temperature hysteresis value for critical min limit.
480 Unit: millidegree Celsius
482 Must be reported as an absolute temperature, NOT a delta
483 from the critical min value.
487 What: /sys/class/hwmon/hwmonX/tempY_offset
489 Temperature offset which is added to the temperature reading
492 Unit: millidegree Celsius
496 What: /sys/class/hwmon/hwmonX/tempY_label
498 Suggested temperature channel label.
502 Should only be created if the driver has hints about what
503 this temperature channel is being used for, and user-space
504 doesn't. In all other cases, the label is provided by
509 What: /sys/class/hwmon/hwmonX/tempY_lowest
511 Historical minimum temperature
513 Unit: millidegree Celsius
517 What: /sys/class/hwmon/hwmonX/tempY_highest
519 Historical maximum temperature
521 Unit: millidegree Celsius
525 What: /sys/class/hwmon/hwmonX/tempY_reset_history
527 Reset temp_lowest and temp_highest
531 What: /sys/class/hwmon/hwmonX/temp_reset_history
533 Reset temp_lowest and temp_highest for all sensors
537 What: /sys/class/hwmon/hwmonX/tempY_enable
539 Enable or disable the sensors.
541 When disabled the sensor read will return -ENODATA.
548 What: /sys/class/hwmon/hwmonX/tempY_rated_min
550 Minimum rated temperature.
552 Unit: millidegree Celsius
556 What: /sys/class/hwmon/hwmonX/tempY_rated_max
558 Maximum rated temperature.
560 Unit: millidegree Celsius
564 What: /sys/class/hwmon/hwmonX/currY_max
572 What: /sys/class/hwmon/hwmonX/currY_min
580 What: /sys/class/hwmon/hwmonX/currY_lcrit
582 Current critical low value
588 What: /sys/class/hwmon/hwmonX/currY_crit
590 Current critical high value.
596 What: /sys/class/hwmon/hwmonX/currY_input
604 What: /sys/class/hwmon/hwmonX/currY_average
612 What: /sys/class/hwmon/hwmonX/currY_lowest
614 Historical minimum current
620 What: /sys/class/hwmon/hwmonX/currY_highest
622 Historical maximum current
626 What: /sys/class/hwmon/hwmonX/currY_reset_history
628 Reset currX_lowest and currX_highest
632 What: /sys/class/hwmon/hwmonX/curr_reset_history
634 Reset currX_lowest and currX_highest for all sensors
638 What: /sys/class/hwmon/hwmonX/currY_enable
640 Enable or disable the sensors.
642 When disabled the sensor read will return -ENODATA.
649 What: /sys/class/hwmon/hwmonX/currY_rated_min
651 Minimum rated current.
657 What: /sys/class/hwmon/hwmonX/currY_rated_max
659 Maximum rated current.
665 What: /sys/class/hwmon/hwmonX/powerY_average
673 What: /sys/class/hwmon/hwmonX/powerY_average_interval
675 Power use averaging interval. A poll
676 notification is sent to this file if the
677 hardware changes the averaging interval.
683 What: /sys/class/hwmon/hwmonX/powerY_average_interval_max
685 Maximum power use averaging interval
691 What: /sys/class/hwmon/hwmonX/powerY_average_interval_min
693 Minimum power use averaging interval
699 What: /sys/class/hwmon/hwmonX/powerY_average_highest
701 Historical average maximum power use
707 What: /sys/class/hwmon/hwmonX/powerY_average_lowest
709 Historical average minimum power use
715 What: /sys/class/hwmon/hwmonX/powerY_average_max
717 A poll notification is sent to
718 `powerY_average` when power use
719 rises above this value.
725 What: /sys/class/hwmon/hwmonX/powerY_average_min
727 A poll notification is sent to
728 `powerY_average` when power use
729 sinks below this value.
735 What: /sys/class/hwmon/hwmonX/powerY_input
737 Instantaneous power use
743 What: /sys/class/hwmon/hwmonX/powerY_input_highest
745 Historical maximum power use
751 What: /sys/class/hwmon/hwmonX/powerY_input_lowest
753 Historical minimum power use
759 What: /sys/class/hwmon/hwmonX/powerY_reset_history
761 Reset input_highest, input_lowest,
762 average_highest and average_lowest.
766 What: /sys/class/hwmon/hwmonX/powerY_accuracy
768 Accuracy of the power meter.
774 What: /sys/class/hwmon/hwmonX/powerY_cap
776 If power use rises above this limit, the
777 system should take action to reduce power use.
778 A poll notification is sent to this file if the
779 cap is changed by the hardware. The `*_cap`
780 files only appear if the cap is known to be
781 enforced by hardware.
787 What: /sys/class/hwmon/hwmonX/powerY_cap_hyst
789 Margin of hysteresis built around capping and
796 What: /sys/class/hwmon/hwmonX/powerY_cap_max
798 Maximum cap that can be set.
804 What: /sys/class/hwmon/hwmonX/powerY_cap_min
806 Minimum cap that can be set.
812 What: /sys/class/hwmon/hwmonX/powerY_max
820 What: /sys/class/hwmon/hwmonX/powerY_crit
822 Critical maximum power.
824 If power rises to or above this limit, the
825 system is expected take drastic action to reduce
826 power consumption, such as a system shutdown or
827 a forced powerdown of some devices.
833 What: /sys/class/hwmon/hwmonX/powerY_enable
835 Enable or disable the sensors.
837 When disabled the sensor read will return
845 What: /sys/class/hwmon/hwmonX/powerY_rated_min
853 What: /sys/class/hwmon/hwmonX/powerY_rated_max
861 What: /sys/class/hwmon/hwmonX/energyY_input
863 Cumulative energy use
869 What: /sys/class/hwmon/hwmonX/energyY_enable
871 Enable or disable the sensors.
873 When disabled the sensor read will return
881 What: /sys/class/hwmon/hwmonX/humidityY_input
885 Unit: milli-percent (per cent mille, pcm)
890 What: /sys/class/hwmon/hwmonX/humidityY_enable
892 Enable or disable the sensors
894 When disabled the sensor read will return
902 What: /sys/class/hwmon/hwmonX/humidityY_rated_min
904 Minimum rated humidity.
906 Unit: milli-percent (per cent mille, pcm)
910 What: /sys/class/hwmon/hwmonX/humidityY_rated_max
912 Maximum rated humidity.
914 Unit: milli-percent (per cent mille, pcm)
919 What: /sys/class/hwmon/hwmonX/intrusionY_alarm
921 Chassis intrusion detection
924 - 1: intrusion detected
928 Contrary to regular alarm flags which clear themselves
929 automatically when read, this one sticks until cleared by
930 the user. This is done by writing 0 to the file. Writing
931 other values is unsupported.
933 What: /sys/class/hwmon/hwmonX/intrusionY_beep
935 Chassis intrusion beep
942 What: /sys/class/hwmon/hwmonX/device/pec
944 PEC support on I2C devices