path: root/Documentation
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authorLinus Torvalds <>2013-05-09 09:40:49 -0700
committerLinus Torvalds <>2013-05-09 09:40:49 -0700
commitb29bdba51924f6fd5971352ba111784dee3a5853 (patch)
tree95f8b7adfd75ce1d6c86b06f9347247aefecd075 /Documentation
parente0fd9affeb64088eff407dfc98bbd3a5c17ea479 (diff)
parentde6558dc964f6a3243218f17d8032ad810864e2b (diff)
Merge branch 'next' of git://
Pull thermal management update from Zhang Rui: "The most important one is to build thermal core and governor and cpu cooling code into one module. This fixes a regression that thermal core does not work if it is built as module, since 3.7. I'll backport them to stable kernel once those changes are in upstream. The largest batch is the thermal kernel-doc & coding style updates/cleanups from Eduardo. Highlights: - build all thermal framework code into one module to fix a regression that thermal does not work if it is built as module. - Marvell Armada 370/XP thermal sensor driver - thermal core/cpu cooling kernel-doc & coding style updates and cleanups. - Add Eduardo Valentin as thermal sub-maintainer, both in mailing list and patchwork. He will help me on arm thermal drivers." * 'next' of git:// (68 commits) thermal: db8500_cpufreq_cooling: remove usage of IS_ERR_OR_NULL() thermal: thermal_core: remove usage of IS_ERR_OR_NULL thermal: cpu_cooling: improve line breaking thermal: cpu_cooling: alignment improvements thermal: cpu_cooling: remove warning thermal: cpu_cooling: remove trailing blank line thermal: cpu_cooling: align on open parenthesis thermal: cpu_cooling: standardize comment style thermal: cpu_cooling: standardize end of function thermal: cpu_cooling: remove trailing white spaces Thermal: update documentation for thermal_zone_device_register thermal: update kernel-doc for thermal_zone_device_register thermal: update kernel-doc for create_trip_attrs thermal: update kernel-doc for thermal_cooling_device_register thermal: update kernel-doc for thermal_zone_unbind_cooling_device thermal: update kernel-doc for thermal_zone_bind_cooling_device thermal: use EXPORT_SYMBOL_GPL thermal: rename notify_thermal_framework to thermal_notify_framework thermal: update driver license thermal: use strlcpy instead of strcpy ...
Diffstat (limited to 'Documentation')
3 files changed, 42 insertions, 16 deletions
diff --git a/Documentation/devicetree/bindings/thermal/armada-thermal.txt b/Documentation/devicetree/bindings/thermal/armada-thermal.txt
new file mode 100644
index 000000000000..fff93d5f92de
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/armada-thermal.txt
@@ -0,0 +1,22 @@
+* Marvell Armada 370/XP thermal management
+Required properties:
+- compatible: Should be set to one of the following:
+ marvell,armada370-thermal
+ marvell,armadaxp-thermal
+- reg: Device's register space.
+ Two entries are expected, see the examples below.
+ The first one is required for the sensor register;
+ the second one is required for the control register
+ to be used for sensor initialization (a.k.a. calibration).
+ thermal@d0018300 {
+ compatible = "marvell,armada370-thermal";
+ reg = <0xd0018300 0x4
+ 0xd0018304 0x4>;
+ status = "okay";
+ };
diff --git a/Documentation/thermal/exynos_thermal_emulation b/Documentation/thermal/exynos_thermal_emulation
index b73bbfb697bb..36a3e79c1203 100644
--- a/Documentation/thermal/exynos_thermal_emulation
+++ b/Documentation/thermal/exynos_thermal_emulation
@@ -13,11 +13,11 @@ Thermal emulation mode supports software debug for TMU's operation. User can set
manually with software code and TMU will read current temperature from user value not from
sensor's value.
-Enabling CONFIG_EXYNOS_THERMAL_EMUL option will make this support in available.
-When it's enabled, sysfs node will be created under
-/sys/bus/platform/devices/'exynos device name'/ with name of 'emulation'.
+Enabling CONFIG_THERMAL_EMULATION option will make this support available.
+When it's enabled, sysfs node will be created as
+/sys/devices/virtual/thermal/thermal_zone'zone id'/emul_temp.
-The sysfs node, 'emulation', will contain value 0 for the initial state. When you input any
+The sysfs node, 'emul_node', will contain value 0 for the initial state. When you input any
temperature you want to update to sysfs node, it automatically enable emulation mode and
current temperature will be changed into it.
(Exynos also supports user changable delay time which would be used to delay of
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index 6859661c9d31..a71bd5b90fe8 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -31,15 +31,17 @@ temperature) and throttle appropriate devices.
1. thermal sysfs driver interface functions
1.1 thermal zone device interface
-1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *name,
+1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *type,
int trips, int mask, void *devdata,
- struct thermal_zone_device_ops *ops)
+ struct thermal_zone_device_ops *ops,
+ const struct thermal_zone_params *tzp,
+ int passive_delay, int polling_delay))
This interface function adds a new thermal zone device (sensor) to
/sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
thermal cooling devices registered at the same time.
- name: the thermal zone name.
+ type: the thermal zone type.
trips: the total number of trip points this thermal zone supports.
mask: Bit string: If 'n'th bit is set, then trip point 'n' is writeable.
devdata: device private data
@@ -57,6 +59,12 @@ temperature) and throttle appropriate devices.
will be fired.
.set_emul_temp: set the emulation temperature which helps in debugging
different threshold temperature points.
+ tzp: thermal zone platform parameters.
+ passive_delay: number of milliseconds to wait between polls when
+ performing passive cooling.
+ polling_delay: number of milliseconds to wait between polls when checking
+ whether trip points have been crossed (0 for interrupt driven systems).
1.1.2 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
@@ -265,6 +273,10 @@ emul_temp
Unit: millidegree Celsius
WO, Optional
+ WARNING: Be careful while enabling this option on production systems,
+ because userland can easily disable the thermal policy by simply
+ flooding this sysfs node with low temperature values.
* Cooling device attributes *
@@ -363,7 +375,7 @@ This function returns the thermal_instance corresponding to a given
{thermal_zone, cooling_device, trip_point} combination. Returns NULL
if such an instance does not exist.
This function handles the trip events from sensor drivers. It starts
throttling the cooling devices according to the policy configured.
For CRITICAL and HOT trip points, this notifies the respective drivers,
@@ -375,11 +387,3 @@ platform data is provided, this uses the step_wise throttling policy.
This function serves as an arbitrator to set the state of a cooling
device. It sets the cooling device to the deepest cooling state if
-This function lets the various thermal governors to register themselves
-with the Thermal framework. At run time, depending on a zone's platform
-data, a particular governor is used for throttling.
-This function unregisters a governor from the thermal framework.