------------------------------------------------
The libsensors library offers an interface to the raw sensors data
-through the sysfs interface. See libsensors documentation and source for
-further information. As of writing this document, libsensors
-(from lm_sensors 2.8.3) is heavily chip-dependent. Adding or updating
-support for any given chip requires modifying the library's code.
-This is because libsensors was written for the procfs interface
-older kernel modules were using, which wasn't standardized enough.
-Recent versions of libsensors (from lm_sensors 2.8.2 and later) have
-support for the sysfs interface, though.
-
-The new sysfs interface was designed to be as chip-independent as
-possible.
+through the sysfs interface. Since lm-sensors 3.0.0, libsensors is
+completely chip-independent. It assumes that all the kernel drivers
+implement the standard sysfs interface described in this document.
+This makes adding or updating support for any given chip very easy, as
+libsensors, and applications using it, do not need to be modified.
+This is a major improvement compared to lm-sensors 2.
Note that motherboards vary widely in the connections to sensor chips.
There is no standard that ensures, for example, that the second
will have to implement conversion, labeling and hiding of inputs. For
this reason, it is still not recommended to bypass the library.
-If you are developing a userspace application please send us feedback on
-this standard.
-
-Note that this standard isn't completely established yet, so it is subject
-to changes. If you are writing a new hardware monitoring driver those
-features can't seem to fit in this interface, please contact us with your
-extension proposal. Keep in mind that backward compatibility must be
-preserved.
-
Each chip gets its own directory in the sysfs /sys/devices tree. To
find all sensor chips, it is easier to follow the device symlinks from
/sys/class/hwmon/hwmon*.
+Up to lm-sensors 3.0.0, libsensors looks for hardware monitoring attributes
+in the "physical" device directory. Since lm-sensors 3.0.1, attributes found
+in the hwmon "class" device directory are also supported. Complex drivers
+(e.g. drivers for multifunction chips) may want to use this possibility to
+avoid namespace pollution. The only drawback will be that older versions of
+libsensors won't support the driver in question.
+
All sysfs values are fixed point numbers.
There is only one value per file, unlike the older /proc specification.
[0-*] denotes any positive number starting from 0
[1-*] denotes any positive number starting from 1
RO read only value
+WO write only value
RW read/write value
Read/write values may be read-only for some chips, depending on the
Unit: revolution/min (RPM)
RW
+fan[1-*]_max Fan maximum value
+ Unit: revolution/min (RPM)
+ Only rarely supported by the hardware.
+ RW
+
fan[1-*]_input Fan input value.
Unit: revolution/min (RPM)
RO
user-space.
RO
+temp[1-*]_lowest
+ Historical minimum temperature
+ Unit: millidegree Celsius
+ RO
+
+temp[1-*]_highest
+ Historical maximum temperature
+ Unit: millidegree Celsius
+ RO
+
+temp[1-*]_reset_history
+ Reset temp_lowest and temp_highest
+ WO
+
+temp_reset_history
+ Reset temp_lowest and temp_highest for all sensors
+ WO
+
Some chips measure temperature using external thermistors and an ADC, and
report the temperature measurement as a voltage. Converting this voltage
back to a temperature (or the other way around for limits) requires
Unit: milliampere
RO
+*********
+* Power *
+*********
+
+power[1-*]_average Average power use
+ Unit: microWatt
+ RO
+
+power[1-*]_average_interval Power use averaging interval
+ Unit: milliseconds
+ RW
+
+power[1-*]_average_highest Historical average maximum power use
+ Unit: microWatt
+ RO
+
+power[1-*]_average_lowest Historical average minimum power use
+ Unit: microWatt
+ RO
+
+power[1-*]_input Instantaneous power use
+ Unit: microWatt
+ RO
+
+power[1-*]_input_highest Historical maximum power use
+ Unit: microWatt
+ RO
+
+power[1-*]_input_lowest Historical minimum power use
+ Unit: microWatt
+ RO
+
+power[1-*]_reset_history Reset input_highest, input_lowest,
+ average_highest and average_lowest.
+ WO
+
+**********
+* Energy *
+**********
+
+energy[1-*]_input Cumulative energy use
+ Unit: microJoule
+ RO
+
**********
* Alarms *
in[0-*]_min_alarm
in[0-*]_max_alarm
fan[1-*]_min_alarm
+fan[1-*]_max_alarm
temp[1-*]_min_alarm
temp[1-*]_max_alarm
temp[1-*]_crit_alarm
RW
+***********************
+* Intrusion detection *
+***********************
+
+intrusion[0-*]_alarm
+ Chassis intrusion detection
+ 0: OK
+ 1: intrusion detected
+ RW
+ Contrary to regular alarm flags which clear themselves
+ automatically when read, this one sticks until cleared by
+ the user. This is done by writing 0 to the file. Writing
+ other values is unsupported.
+
+intrusion[0-*]_beep
+ Chassis intrusion beep
+ 0: disable
+ 1: enable
+ RW
+
+
sysfs attribute writes interpretation
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git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff