Commit Graph

37 Commits

Author SHA1 Message Date
Mauro Carvalho Chehab 7ebd8b66dd docs: hwmon: Add an index file and rename docs to *.rst
Now that all files were converted to ReST format, rename them
and add an index.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-04-17 10:37:23 -07:00
Viresh Kumar 8ea229511e thermal: Add cooling device's statistics in sysfs
This extends the sysfs interface for thermal cooling devices and exposes
some pretty useful statistics. These statistics have proven to be quite
useful specially while doing benchmarks related to the task scheduler,
where we want to make sure that nothing has disrupted the test,
specially the cooling device which may have put constraints on the CPUs.
The information exposed here tells us to what extent the CPUs were
constrained by the thermal framework.

The write-only "reset" file is used to reset the statistics.

The read-only "time_in_state_ms" file shows the time (in msec) spent by the
device in the respective cooling states, and it prints one line per
cooling state.

The read-only "total_trans" file shows single positive integer value
showing the total number of cooling state transitions the device has
gone through since the time the cooling device is registered or the time
when statistics were reset last.

The read-only "trans_table" file shows a two dimensional matrix, where
an entry <i,j> (row i, column j) represents the number of transitions
from State_i to State_j.

This is how the directory structure looks like for a single cooling
device:

$ ls -R /sys/class/thermal/cooling_device0/
/sys/class/thermal/cooling_device0/:
cur_state  max_state  power  stats  subsystem  type  uevent

/sys/class/thermal/cooling_device0/power:
autosuspend_delay_ms  runtime_active_time  runtime_suspended_time
control               runtime_status

/sys/class/thermal/cooling_device0/stats:
reset  time_in_state_ms  total_trans  trans_table

This is tested on ARM 64-bit Hisilicon hikey620 board running Ubuntu and
ARM 64-bit Hisilicon hikey960 board running Android.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2018-04-02 21:49:01 +08:00
Keerthy ef1d87e06a thermal: core: Add a back up thermal shutdown mechanism
orderly_poweroff is triggered when a graceful shutdown
of system is desired. This may be used in many critical states of the
kernel such as when subsystems detects conditions such as critical
temperature conditions. However, in certain conditions in system
boot up sequences like those in the middle of driver probes being
initiated, userspace will be unable to power off the system in a clean
manner and leaves the system in a critical state. In cases like these,
the /sbin/poweroff will return success (having forked off to attempt
powering off the system. However, the system overall will fail to
completely poweroff (since other modules will be probed) and the system
is still functional with no userspace (since that would have shut itself
off).

However, there is no clean way of detecting such failure of userspace
powering off the system. In such scenarios, it is necessary for a backup
workqueue to be able to force a shutdown of the system when orderly
shutdown is not successful after a configurable time period.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2017-05-05 16:01:45 +08:00
Sascha Hauer 060c034a97 thermal: Add support for hardware-tracked trip points
This adds support for hardware-tracked trip points to the device tree
thermal sensor framework.

The framework supports an arbitrary number of trip points. Whenever
the current temperature is updated, the trip points immediately
below and above the current temperature are found. A .set_trips
callback is then called with the temperatures. If there is no trip
point above or below the current temperature, the passed trip
temperature will be -INT_MAX or INT_MAX respectively. In this callback,
the driver should program the hardware such that it is notified
when either of these trip points are triggered. When a trip point
is triggered, the driver should call `thermal_zone_device_update'
for the respective thermal zone. This will cause the trip points
to be updated again.

If .set_trips is not implemented, the framework behaves as before.

This patch is based on an earlier version from Mikko Perttunen
<mikko.perttunen@kapsi.fi>

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: linux-pm@vger.kernel.org
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2016-09-27 14:02:16 +08:00
Rajendra Nayak 4a7069a32c thermal: core: export apis to get slope and offset
Add apis for platform thermal drivers to query for slope and offset
attributes, which might be needed for temperature calculations.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2016-09-27 14:02:16 +08:00
Andy Champ c212ed912b thermal: Syntactic and factual errors in the API document
There are several places where the English in the document is syntactically
invalid, or unclear. There are also one or two factual errors.

Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Andy Champ <andycham@amazon.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2016-05-17 07:28:24 -07:00
Laxman Dewangan 61f846f373 thermal: doc: Add details of devm_thermal_zone_of_sensor_{register,unregister}
Add details of the interface devm_thermal_zone_of_sensor_register()
and devm_thermal_zone_of_sensor_unregister() in the
<thermal/sysfs-api.txt>.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2016-03-09 10:51:41 -08:00
Laxman Dewangan 3a7fd9c737 thermal: doc: Add details of thermal_zone_of_sensor_{register,unregister}
Add details of the interface thermal_zone_of_sensor_register() and
thermal_zone_of_sensor_unregister() in the thermal/sysfs-api.txt.

The details describes the functionality and parameter which
are passed to these interfaces.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2016-03-09 10:31:01 -08:00
Leo Yan ec3fc58b1e thermal: add description for integral_cutoff unit
Add more explicitly description for unit of integral_cutoff which used
by power allocator governor.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-01-14 13:29:08 -07:00
Ni Wade 25a0a5ce16 thermal: add available policies sysfs attribute
The Linux thermal framework support to change thermal governor
policy in userspace, but it can't show what available policies
supported.

This patch adds available_policies attribute to the thermal
framework, it can list the thermal governors which can be
used for a particular zone. This attribute is read only.

Signed-off-by: Wei Ni <wni@nvidia.com>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2015-08-03 23:15:50 +08:00
Eduardo Valentin 9d0be7f481 thermal: support slope and offset coefficients
It is common to have a linear extrapolation from
the current sensor readings and the actual temperature
value. This is specially the case when the sensor
is in use to extrapolate hotspots.

This patch adds slope and offset constants for
single sensor linear extrapolation equation. Because
the same sensor can be use in different locations,
from board to board, these constants are added
as part of thermal_zone_params.

The constants are available through sysfs.

It is up to the device driver to determine
the usage of these values.

Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-11 19:46:52 -07:00
Javi Merino 9f38271c6f thermal: export thermal_zone_parameters to sysfs
It's useful for tuning to be able to edit thermal_zone_parameters from
userspace.  Export them to the thermal_zone sysfs so that they can be
easily changed.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:54 -07:00
Javi Merino bcdcbbc711 thermal: fair_share: generalize the weight concept
The fair share governor has the concept of weights, which is the
influence of each cooling device in a thermal zone.  The current
implementation forces the weights of all cooling devices in a thermal
zone to add up to a 100.  This complicates setups, as you need to know
in advance how many cooling devices you are going to have.  If you bind a
new cooling device, you have to modify all the other cooling devices
weights, which is error prone.  Furthermore, you can't specify a
"default" weight for platforms since that default value depends on the
number of cooling devices in the platform.

This patch generalizes the concept of weight by allowing any number to
be a "weight".  Weights are now relative to each other.  Platforms that
don't specify weights get the same default value for all their cooling
devices, so all their cdevs are considered to be equally influential.

It's important to note that previous users of the weights don't need to
alter the code: percentages continue to work as they used to.  This
patch just removes the constraint of all the weights in a thermal zone
having to add up to a 100.  If they do, you get the same behavior as
before.  If they don't, fair share now works for that platform.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:51 -07:00
Javi Merino db91651311 thermal: export weight to sysfs
It's useful to have access to the weights for the cooling devices for
thermal zones and change them if needed.  Export them to sysfs.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:51 -07:00
Kapileshwar Singh 6cd9e9f629 thermal: of: fix cooling device weights in device tree
Currently you can specify the weight of the cooling device in the device
tree but that information is not populated to the
thermal_bind_params where the fair share governor expects it to
be.  The of thermal zone device doesn't have a thermal_bind_params
structure and arguably it's better to pass the weight inside the
thermal_instance as it is specific to the bind of a cooling device to a
thermal zone parameter.

Core thermal code is fixed to populate the weight in the instance from
the thermal_bind_params, so platform code that was passing the weight
inside the thermal_bind_params continue to work seamlessly.

While we are at it, create a default value for the weight parameter for
those thermal zones that currently don't define it and remove the
hardcoded default in of-thermal.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Peter Feuerer <peter@piie.net>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Kapileshwar Singh <kapileshwar.singh@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:50 -07:00
Eduardo Valentin a8892d8389 thermal: thermal_core: allow binding with limits on bind_params
When registering a thermal zone device using platform information
via bind_params, the thermal framework will always perform the
cdev binding using the lowest and highest limits (THERMAL_NO_LIMIT).

This patch changes the data structures so that it is possible
to inform what are the desired limits for each trip point
inside a bind_param. The way the binding is performed is also
changed so that it uses the new data structure.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
2013-09-03 09:10:24 -04:00
Eduardo Valentin ccba4ffd9e drivers: thermal: make usage of CONFIG_THERMAL_HWMON optional
When registering a new thermal_device, the thermal framework
will always add a hwmon sysfs interface.

This patch adds a flag to make this behavior optional. Now
when registering a new thermal device, the caller can
optionally inform if hwmon interface is desirable. This can
be done by means of passing a thermal_zone_params.no_hwmon == true.

In order to keep same behavior as of today, all current
calls will by default create the hwmon interface.

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-acpi@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Zhang Rui <rui.zhang@intel.com>
Suggested-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
2013-09-03 09:10:11 -04:00
Zhang Rui 514e6d2014 Thermal: update documentation for thermal_zone_device_register
Update kernel Documentation for thermal_zone_device_register.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-04-27 09:16:04 +08:00
Eduardo Valentin 7b73c99377 thermal: rename notify_thermal_framework to thermal_notify_framework
To follow the prefix names used by the thermal functions,
this patch renames notify_thermal_framework to thermal_notify_framework.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-04-25 00:56:16 +08:00
Zhang Rui 80a26a5c22 Thermal: build thermal governors into thermal_sys module
The thermal governors are part of the thermal framework,
rather than a seperate feature/module.
Because the generic thermal layer can not work without
thermal governors, and it must load the thermal governors
during its initialization.

Build them into one module in this patch.

This also fix a problem that the generic thermal layer does not
work when CONFIG_THERMAL=m and CONFIG_THERMAL_GOV_XXX=y.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
2013-04-14 23:28:43 +08:00
Eduardo Valentin 8837295a73 thermal: add a warning for temperature emulation feature
Because this feature is for debuging purposes, it is highly
recommended to do not enable this on production systems.
This patch adds warnings for system integrators, so that
people are aware of this potential security issue.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-04-02 21:34:42 +08:00
Amit Daniel Kachhap e6e238c38b thermal: sysfs: Add a new sysfs node emul_temp for thermal emulation
This patch adds support to set the emulated temperature method in
thermal zone (sensor). After setting this feature thermal zone may
report this temperature and not the actual temperature. The emulation
implementation may be based on sensor capability through platform
specific handler or pure software emulation if no platform handler defined.

This is useful in debugging different temperature threshold and its
associated cooling action. Critical threshold's cannot be emulated.
Writing 0 on this node should disable emulation.

Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-02-06 13:45:42 +08:00
Eduardo Valentin 8ab3e6a08a thermal: Use thermal zone device id in netlink messages
This patch changes the function thermal_generate_netlink_event
to receive a thermal zone device instead of a originator id.

This way, the messages will always be bound to a thermal zone.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-01-16 10:46:46 +08:00
Durgadoss R 6ea083b18d Thermal: Add documentation for platform layer data
This patch adds documentation for thermal_bind_params
and thermal_zone_params structures. Also, adds details
on EXPORT_SYMBOL APIs.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2012-11-05 14:00:09 +08:00
Zhang Rui 9d99842f99 Thermal: set upper and lower limits
set upper and lower limits when binding
a thermal cooling device to a thermal zone device.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Eduardo Valentin <eduardo.valentin@ti.com>
2012-09-24 14:44:36 +08:00
Zhang Rui 8eaa8d6ca2 Thermal: Documentation update
With commit 6503e5df08,
the value of /sys/class/thermal/thermal_zoneX/mode has been changed
from user/kernel to enabled/disabled.
Update the documentation so that users won't be confused.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-24 23:20:40 -04:00
Durgadoss R 27365a6c7d Thermal: Add Hysteresis attributes
The Linux Thermal Framework does not support hysteresis
attributes. Most thermal sensors, today, have a
hysteresis value associated with trip points.

This patch adds hysteresis attributes on a per-trip-point
basis, to the Thermal Framework. These attributes are
optionally writable.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-24 23:19:26 -04:00
Durgadoss R c56f5c0342 Thermal: Make Thermal trip points writeable
Some of the thermal drivers using the Generic Thermal Framework
require (all/some) trip points to be writeable. This patch makes
the trip point temperatures writeable on a per-trip point basis,
and modifies the required function call in thermal.c. This patch
also updates the Documentation to reflect the new change.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-24 23:17:20 -04:00
Jean Delvare 2d58d7ea91 thermal: Rename generate_netlink_event
It doesn't seem right for the thermal subsystem to export a symbol
named generate_netlink_event. This function is thermal-specific and
its name should reflect that fact. Rename it to
thermal_generate_netlink_event.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: R.Durgadoss <durgadoss.r@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-01-23 03:15:25 -05:00
R.Durgadoss 4cb1872870 thermal: Add event notification to thermal framework
This patch adds event notification support to the generic
thermal sysfs framework in the kernel. The notification is in the
form of a netlink event.

Signed-off-by: R.Durgadoss <durgadoss.r@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 00:08:35 -05:00
Frans Pop 3d8e3ad879 thermal: add sanity check for the passive attribute
Values below 1000 milli-celsius don't make sense and can cause the
system to go into a thermal heart attack: the actual temperature
will always be lower and thus the system will be throttled down to
its lowest setting.

An additional problem is that values below 1000 will show as 0 in
/proc/acpi/thermal/TZx/trip_points:passive.

cat passive
0
echo -n 90 >passive
bash: echo: write error: Invalid argument
echo -n 90000 >passive
cat passive
90000

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-05 18:18:10 -05:00
Frans Pop 29226ed3c3 thermal: sysfs-api.txt - document passive attribute for thermal zones
Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-05 18:11:18 -05:00
Frans Pop 38bb0849a6 thermal: sysfs-api.txt - reformat for improved readability
The document currently uses large indentations which make the text
too wide for easy readability. Also improve general consistency.

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-05 18:06:05 -05:00
Zhang Rui e9ae71078b thermal: update the documentation
Update the documentation for the thermal driver hwmon sys I/F.

Change the ACPI thermal zone type to be consistent with hwmon.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-04-29 02:49:47 -04:00
Zhang, Rui 3152fb9f11 thermal: fix generic thermal I/F for hwmon
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-13 01:49:01 -04:00
Len Brown 543a956140 ACPI: thermal: syntax, spelling, kernel-doc
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-02-07 23:48:04 -05:00
Zhang Rui 203d3d4aa4 the generic thermal sysfs driver
The Generic Thermal sysfs driver for thermal management.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Thomas Sujith <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-02-01 23:12:19 -05:00