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authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-04 18:32:38 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-04 18:32:38 +0300
commit95faf6ba654dd334617f347023e65b06d791c4a6 (patch)
treed2b6b8dbb5bf3566ed696e0fb918e4ee2589f171 /Documentation/hwmon
parent5c904c66ed4e86c31ac7c033b64274cebed04e0e (diff)
parent27e0bcd02990f7291adb0f111e300f06c495d509 (diff)
downloadlinux-95faf6ba654dd334617f347023e65b06d791c4a6.tar.xz
Merge tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 5.16-rc1. All of these have been in linux-next for a while now with no reported problems. Included in here are: - big update and cleanup of the sysfs abi documentation files and scripts from Mauro. We are almost at the place where we can properly check that the running kernel's sysfs abi is documented fully. - firmware loader updates - dyndbg updates - kernfs cleanups and fixes from Christoph - device property updates - component fix - other minor driver core cleanups and fixes" * tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (122 commits) device property: Drop redundant NULL checks x86/build: Tuck away built-in firmware under FW_LOADER vmlinux.lds.h: wrap built-in firmware support under FW_LOADER firmware_loader: move struct builtin_fw to the only place used x86/microcode: Use the firmware_loader built-in API firmware_loader: remove old DECLARE_BUILTIN_FIRMWARE() firmware_loader: formalize built-in firmware API component: do not leave master devres group open after bind dyndbg: refine verbosity 1-4 summary-detail gpiolib: acpi: Replace custom code with device_match_acpi_handle() i2c: acpi: Replace custom function with device_match_acpi_handle() driver core: Provide device_match_acpi_handle() helper dyndbg: fix spurious vNpr_info change dyndbg: no vpr-info on empty queries dyndbg: vpr-info on remove-module complete, not starting device property: Add missed header in fwnode.h Documentation: dyndbg: Improve cli param examples dyndbg: Remove support for ddebug_query param dyndbg: make dyndbg a known cli param dyndbg: show module in vpr-info in dd-exec-queries ...
Diffstat (limited to 'Documentation/hwmon')
-rw-r--r--Documentation/hwmon/sysfs-interface.rst596
1 files changed, 42 insertions, 554 deletions
diff --git a/Documentation/hwmon/sysfs-interface.rst b/Documentation/hwmon/sysfs-interface.rst
index 13c5acb72d63..85652a6aaa3e 100644
--- a/Documentation/hwmon/sysfs-interface.rst
+++ b/Documentation/hwmon/sysfs-interface.rst
@@ -89,6 +89,8 @@ hardware implementation.
All entries (except name) are optional, and should only be created in a
given driver if the chip has the feature.
+See Documentation/ABI/testing/sysfs-class-hwmon for a complete description
+of the attributes.
*****************
Global attributes
@@ -96,22 +98,9 @@ Global attributes
`name`
The chip name.
- This should be a short, lowercase string, not containing
- whitespace, dashes, or the wildcard character '*'.
- This attribute represents the chip name. It is the only
- mandatory attribute.
- I2C devices get this attribute created automatically.
-
- RO
`update_interval`
The interval at which the chip will update readings.
- Unit: millisecond
-
- RW
-
- Some devices have a variable update rate or interval.
- This attribute can be used to change it to the desired value.
********
@@ -121,148 +110,51 @@ Voltages
`in[0-*]_min`
Voltage min value.
- Unit: millivolt
-
- RW
-
`in[0-*]_lcrit`
Voltage critical min value.
- Unit: millivolt
-
- RW
-
- If voltage drops to or below this limit, the system may
- take drastic action such as power down or reset. At the very
- least, it should report a fault.
-
`in[0-*]_max`
Voltage max value.
- Unit: millivolt
-
- RW
-
`in[0-*]_crit`
Voltage critical max value.
- Unit: millivolt
-
- RW
-
- If voltage reaches or exceeds this limit, the system may
- take drastic action such as power down or reset. At the very
- least, it should report a fault.
-
`in[0-*]_input`
Voltage input value.
- Unit: millivolt
-
- RO
-
- Voltage measured on the chip pin.
-
- Actual voltage depends on the scaling resistors on the
- motherboard, as recommended in the chip datasheet.
-
- This varies by chip and by motherboard.
- Because of this variation, values are generally NOT scaled
- by the chip driver, and must be done by the application.
- However, some drivers (notably lm87 and via686a)
- do scale, because of internal resistors built into a chip.
- These drivers will output the actual voltage. Rule of
- thumb: drivers should report the voltage values at the
- "pins" of the chip.
-
`in[0-*]_average`
Average voltage
- Unit: millivolt
-
- RO
-
`in[0-*]_lowest`
Historical minimum voltage
- Unit: millivolt
-
- RO
-
`in[0-*]_highest`
Historical maximum voltage
- Unit: millivolt
-
- RO
-
`in[0-*]_reset_history`
Reset inX_lowest and inX_highest
- WO
-
`in_reset_history`
Reset inX_lowest and inX_highest for all sensors
- WO
-
`in[0-*]_label`
Suggested voltage channel label.
- Text string
-
- Should only be created if the driver has hints about what
- this voltage channel is being used for, and user-space
- doesn't. In all other cases, the label is provided by
- user-space.
-
- RO
-
`in[0-*]_enable`
Enable or disable the sensors.
- When disabled the sensor read will return -ENODATA.
-
- - 1: Enable
- - 0: Disable
-
- RW
-
`cpu[0-*]_vid`
CPU core reference voltage.
- Unit: millivolt
-
- RO
-
- Not always correct.
-
`vrm`
Voltage Regulator Module version number.
- RW (but changing it should no more be necessary)
-
- Originally the VRM standard version multiplied by 10, but now
- an arbitrary number, as not all standards have a version
- number.
-
- Affects the way the driver calculates the CPU core reference
- voltage from the vid pins.
-
`in[0-*]_rated_min`
Minimum rated voltage.
- Unit: millivolt
-
- RO
-
`in[0-*]_rated_max`
Maximum rated voltage.
- Unit: millivolt
-
- RO
-
Also see the Alarms section for status flags associated with voltages.
@@ -273,83 +165,27 @@ Fans
`fan[1-*]_min`
Fan minimum value
- 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
-
`fan[1-*]_div`
Fan divisor.
- Integer value in powers of two (1, 2, 4, 8, 16, 32, 64, 128).
-
- RW
-
- Some chips only support values 1, 2, 4 and 8.
- Note that this is actually an internal clock divisor, which
- affects the measurable speed range, not the read value.
-
`fan[1-*]_pulses`
Number of tachometer pulses per fan revolution.
- Integer value, typically between 1 and 4.
-
- RW
-
- This value is a characteristic of the fan connected to the
- device's input, so it has to be set in accordance with the fan
- model.
-
- Should only be created if the chip has a register to configure
- the number of pulses. In the absence of such a register (and
- thus attribute) the value assumed by all devices is 2 pulses
- per fan revolution.
-
`fan[1-*]_target`
Desired fan speed
- Unit: revolution/min (RPM)
-
- RW
-
- Only makes sense if the chip supports closed-loop fan speed
- control based on the measured fan speed.
-
`fan[1-*]_label`
Suggested fan channel label.
- Text string
-
- Should only be created if the driver has hints about what
- this fan channel is being used for, and user-space doesn't.
- In all other cases, the label is provided by user-space.
-
- RO
-
`fan[1-*]_enable`
Enable or disable the sensors.
- When disabled the sensor read will return -ENODATA.
-
- - 1: Enable
- - 0: Disable
-
- RW
-
Also see the Alarms section for status flags associated with fans.
@@ -360,63 +196,25 @@ PWM
`pwm[1-*]`
Pulse width modulation fan control.
- Integer value in the range 0 to 255
-
- RW
-
- 255 is max or 100%.
-
`pwm[1-*]_enable`
Fan speed control method:
- - 0: no fan speed control (i.e. fan at full speed)
- - 1: manual fan speed control enabled (using `pwm[1-*]`)
- - 2+: automatic fan speed control enabled
-
- Check individual chip documentation files for automatic mode
- details.
-
- RW
-
`pwm[1-*]_mode`
- - 0: DC mode (direct current)
- - 1: PWM mode (pulse-width modulation)
-
- RW
+ direct current or pulse-width modulation.
`pwm[1-*]_freq`
Base PWM frequency in Hz.
- Only possibly available when pwmN_mode is PWM, but not always
- present even then.
-
- RW
-
`pwm[1-*]_auto_channels_temp`
Select which temperature channels affect this PWM output in
auto mode.
- Bitfield, 1 is temp1, 2 is temp2, 4 is temp3 etc...
- Which values are possible depend on the chip used.
-
- RW
-
`pwm[1-*]_auto_point[1-*]_pwm` / `pwm[1-*]_auto_point[1-*]_temp` / `pwm[1-*]_auto_point[1-*]_temp_hyst`
Define the PWM vs temperature curve.
- Number of trip points is chip-dependent. Use this for chips
- which associate trip points to PWM output channels.
-
- RW
-
`temp[1-*]_auto_point[1-*]_pwm` / `temp[1-*]_auto_point[1-*]_temp` / `temp[1-*]_auto_point[1-*]_temp_hyst`
Define the PWM vs temperature curve.
- Number of trip points is chip-dependent. Use this for chips
- which associate trip points to temperature channels.
-
- RW
-
There is a third case where trip points are associated to both PWM output
channels and temperature channels: the PWM values are associated to PWM
output channels while the temperature values are associated to temperature
@@ -434,182 +232,70 @@ Temperatures
`temp[1-*]_type`
Sensor type selection.
- Integers 1 to 6
-
- RW
-
- - 1: CPU embedded diode
- - 2: 3904 transistor
- - 3: thermal diode
- - 4: thermistor
- - 5: AMD AMDSI
- - 6: Intel PECI
-
- Not all types are supported by all chips
-
`temp[1-*]_max`
Temperature max value.
- Unit: millidegree Celsius (or millivolt, see below)
-
- RW
-
`temp[1-*]_min`
Temperature min value.
- Unit: millidegree Celsius
-
- RW
-
`temp[1-*]_max_hyst`
Temperature hysteresis value for max limit.
- Unit: millidegree Celsius
-
- Must be reported as an absolute temperature, NOT a delta
- from the max value.
-
- RW
-
`temp[1-*]_min_hyst`
Temperature hysteresis value for min limit.
- Unit: millidegree Celsius
-
- Must be reported as an absolute temperature, NOT a delta
- from the min value.
-
- RW
`temp[1-*]_input`
- Temperature input value.
-
- Unit: millidegree Celsius
-
- RO
+ Temperature input value.
`temp[1-*]_crit`
Temperature critical max value, typically greater than
corresponding temp_max values.
- Unit: millidegree Celsius
-
- RW
-
`temp[1-*]_crit_hyst`
Temperature hysteresis value for critical limit.
- Unit: millidegree Celsius
-
- Must be reported as an absolute temperature, NOT a delta
- from the critical value.
-
- RW
-
`temp[1-*]_emergency`
Temperature emergency max value, for chips supporting more than
- two upper temperature limits. Must be equal or greater than
- corresponding temp_crit values.
-
- Unit: millidegree Celsius
-
- RW
+ two upper temperature limits.
`temp[1-*]_emergency_hyst`
Temperature hysteresis value for emergency limit.
- Unit: millidegree Celsius
-
- Must be reported as an absolute temperature, NOT a delta
- from the emergency value.
-
- RW
-
`temp[1-*]_lcrit`
Temperature critical min value, typically lower than
corresponding temp_min values.
- Unit: millidegree Celsius
-
- RW
-
`temp[1-*]_lcrit_hyst`
Temperature hysteresis value for critical min limit.
- Unit: millidegree Celsius
-
- Must be reported as an absolute temperature, NOT a delta
- from the critical min value.
-
- RW
-
`temp[1-*]_offset`
Temperature offset which is added to the temperature reading
by the chip.
- Unit: millidegree Celsius
-
- Read/Write value.
-
`temp[1-*]_label`
Suggested temperature channel label.
- Text string
-
- Should only be created if the driver has hints about what
- this temperature channel is being used for, and user-space
- doesn't. In all other cases, the label is provided by
- 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
-
`temp[1-*]_enable`
Enable or disable the sensors.
- When disabled the sensor read will return -ENODATA.
-
- - 1: Enable
- - 0: Disable
-
- RW
-
`temp[1-*]_rated_min`
Minimum rated temperature.
- Unit: millidegree Celsius
-
- RO
-
`temp[1-*]_rated_max`
Maximum rated temperature.
- Unit: millidegree Celsius
-
- RO
-
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
@@ -627,58 +313,28 @@ Currents
********
`curr[1-*]_max`
- Current max value
-
- Unit: milliampere
-
- RW
+ Current max value.
`curr[1-*]_min`
Current min value.
- Unit: milliampere
-
- RW
-
`curr[1-*]_lcrit`
Current critical low value
- Unit: milliampere
-
- RW
-
`curr[1-*]_crit`
Current critical high value.
- Unit: milliampere
-
- RW
-
`curr[1-*]_input`
- Current input value
-
- Unit: milliampere
-
- RO
+ Current input value.
`curr[1-*]_average`
- Average current use
-
- Unit: milliampere
-
- RO
+ Average current use.
`curr[1-*]_lowest`
- Historical minimum current
-
- Unit: milliampere
-
- RO
+ Historical minimum current.
`curr[1-*]_highest`
- Historical maximum current
- Unit: milliampere
- RO
+ Historical maximum current.
`curr[1-*]_reset_history`
Reset currX_lowest and currX_highest
@@ -686,34 +342,17 @@ Currents
WO
`curr_reset_history`
- Reset currX_lowest and currX_highest for all sensors
-
- WO
+ Reset currX_lowest and currX_highest for all sensors.
`curr[1-*]_enable`
Enable or disable the sensors.
- When disabled the sensor read will return -ENODATA.
-
- - 1: Enable
- - 0: Disable
-
- RW
-
`curr[1-*]_rated_min`
Minimum rated current.
- Unit: milliampere
-
- RO
-
`curr[1-*]_rated_max`
Maximum rated current.
- Unit: milliampere
-
- RO
-
Also see the Alarms section for status flags associated with currents.
*****
@@ -721,141 +360,62 @@ Power
*****
`power[1-*]_average`
- Average power use
-
- Unit: microWatt
-
- RO
+ Average power use.
`power[1-*]_average_interval`
- Power use averaging interval. A poll
- notification is sent to this file if the
- hardware changes the averaging interval.
-
- Unit: milliseconds
-
- RW
+ Power use averaging interval.
`power[1-*]_average_interval_max`
- Maximum power use averaging interval
-
- Unit: milliseconds
-
- RO
+ Maximum power use averaging interval.
`power[1-*]_average_interval_min`
- Minimum power use averaging interval
-
- Unit: milliseconds
-
- RO
+ Minimum power use averaging interval.
`power[1-*]_average_highest`
- Historical average maximum power use
-
- Unit: microWatt
-
- RO
+ Historical average maximum power use
`power[1-*]_average_lowest`
- Historical average minimum power use
-
- Unit: microWatt
-
- RO
+ Historical average minimum power use
`power[1-*]_average_max`
- A poll notification is sent to
- `power[1-*]_average` when power use
- rises above this value.
-
- Unit: microWatt
-
- RW
+ A poll notification is sent to `power[1-*]_average` when
+ power use rises above this value.
`power[1-*]_average_min`
- A poll notification is sent to
- `power[1-*]_average` when power use
- sinks below this value.
-
- Unit: microWatt
-
- RW
+ A poll notification is sent to `power[1-*]_average` when
+ power use sinks below this value.
`power[1-*]_input`
- Instantaneous power use
-
- Unit: microWatt
-
- RO
+ Instantaneous power use.
`power[1-*]_input_highest`
- Historical maximum power use
-
- Unit: microWatt
-
- RO
+ Historical maximum power use
`power[1-*]_input_lowest`
- Historical minimum power use
-
- Unit: microWatt
-
- RO
+ Historical minimum power use.
`power[1-*]_reset_history`
- Reset input_highest, input_lowest,
- average_highest and average_lowest.
-
- WO
+ Reset input_highest, input_lowest, average_highest and
+ average_lowest.
`power[1-*]_accuracy`
- Accuracy of the power meter.
-
- Unit: Percent
-
- RO
+ Accuracy of the power meter.
`power[1-*]_cap`
- If power use rises above this limit, the
- system should take action to reduce power use.
- A poll notification is sent to this file if the
- cap is changed by the hardware. The `*_cap`
- files only appear if the cap is known to be
- enforced by hardware.
-
- Unit: microWatt
-
- RW
+ If power use rises above this limit, the
+ system should take action to reduce power use.
`power[1-*]_cap_hyst`
- Margin of hysteresis built around capping and
- notification.
-
- Unit: microWatt
-
- RW
+ Margin of hysteresis built around capping and notification.
`power[1-*]_cap_max`
- Maximum cap that can be set.
-
- Unit: microWatt
-
- RO
+ Maximum cap that can be set.
`power[1-*]_cap_min`
- Minimum cap that can be set.
-
- Unit: microWatt
-
- RO
+ Minimum cap that can be set.
`power[1-*]_max`
- Maximum power.
-
- Unit: microWatt
-
- RW
+ Maximum power.
`power[1-*]_crit`
Critical maximum power.
@@ -923,37 +483,16 @@ Humidity
********
`humidity[1-*]_input`
- Humidity
-
- Unit: milli-percent (per cent mille, pcm)
-
- RO
-
+ Humidity.
`humidity[1-*]_enable`
- Enable or disable the sensors
-
- When disabled the sensor read will return
- -ENODATA.
-
- - 1: Enable
- - 0: Disable
-
- RW
+ Enable or disable the sensors.
`humidity[1-*]_rated_min`
- Minimum rated humidity.
-
- Unit: milli-percent (per cent mille, pcm)
-
- RO
+ Minimum rated humidity.
`humidity[1-*]_rated_max`
- Maximum rated humidity.
-
- Unit: milli-percent (per cent mille, pcm)
-
- RO
+ Maximum rated humidity.
******
Alarms
@@ -1004,30 +543,15 @@ supports it. When this boolean has value 1, the measurement for that
channel should not be trusted.
`fan[1-*]_fault` / `temp[1-*]_fault`
- Input fault condition
-
- - 0: no fault occurred
- - 1: fault condition
-
- RO
+ Input fault condition.
Some chips also offer the possibility to get beeped when an alarm occurs:
`beep_enable`
- Master beep enable
-
- - 0: no beeps
- - 1: beeps
-
- RW
+ Master beep enable.
`in[0-*]_beep`, `curr[1-*]_beep`, `fan[1-*]_beep`, `temp[1-*]_beep`,
- Channel beep
-
- - 0: disable
- - 1: enable
-
- RW
+ Channel beep.
In theory, a chip could provide per-limit beep masking, but no such chip
was seen so far.
@@ -1039,29 +563,8 @@ for compatibility reasons:
`alarms`
Alarm bitmask.
- RO
-
- Integer representation of one to four bytes.
-
- A '1' bit means an alarm.
-
- Chips should be programmed for 'comparator' mode so that
- the alarm will 'come back' after you read the register
- if it is still valid.
-
- Generally a direct representation of a chip's internal
- alarm registers; there is no standard for the position
- of individual bits. For this reason, the use of this
- interface file for new drivers is discouraged. Use
- `individual *_alarm` and `*_fault` files instead.
- Bits are defined in kernel/include/sensors.h.
-
`beep_mask`
Bitmask for beep.
- Same format as 'alarms' with the same bit locations,
- use discouraged for the same reason. Use individual
- `*_beep` files instead.
- RW
*******************
@@ -1069,25 +572,10 @@ 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.
+ Chassis intrusion detection.
`intrusion[0-*]_beep`
- Chassis intrusion beep
-
- 0: disable
- 1: enable
-
- RW
+ Chassis intrusion beep.
****************************
Average sample configuration