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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 19:57:13 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 19:57:13 +0400
commit50851c6248e1a13c45d97c41f6ebcf716093aa5e (patch)
tree792c5721aab6669ca14716a1220222a99c0a3fc3 /Documentation
parent99b8f42ee2ab93077154f09d397cdc1dfb15926e (diff)
parent1f53ef17d3ed6c34868cc8e7aa7c1d351c2fdc95 (diff)
downloadlinux-50851c6248e1a13c45d97c41f6ebcf716093aa5e.tar.xz
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal management update from Zhang Rui: "Highlights: - Introduction of thermal policy support, together with three new thermal governors, including step_wise, user_space, fire_share. - Introduction of ST-Ericsson db8500_thermal driver and ST-Ericsson db8500_cpufreq_cooling driver. - Thermal Kconfig file and Makefile refactor. - Fixes for generic thermal layer, generic cpucooling, rcar thermal driver and Exynos thermal driver." * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (36 commits) Thermal: Fix DEFAULT_THERMAL_GOVERNOR Thermal: fix a NULL pointer dereference when generic thermal layer is built as a module thermal: rcar: add rcar_zone_to_priv() macro thermal: rcar: fixup the unit of temperature thermal: cpu cooling: allow module builds thermal: cpu cooling: use const parameter while registering Thermal: Add ST-Ericsson DB8500 thermal properties and platform data. Thermal: Add ST-Ericsson DB8500 thermal driver. drivers/thermal/Makefile refactor Exynos: Add missing dependency Refactor drivers/thermal/Kconfig thermal: cpu_cooling: Make 'notify_device' static Thermal: Remove the cooling_cpufreq_list. Thermal: fix bug of counting cpu frequencies. Thermal: add indent for code alignment. thermal: rcar_thermal: remove explicitly used devm_kfree/iounap() thermal: user_space: Add missing static storage class specifiers thermal: fair_share: Add missing static storage class specifiers thermal: step_wise: Add missing static storage class specifiers Thermal: Fix oops and unlocking in thermal_sys.c ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/thermal/db8500-thermal.txt44
-rw-r--r--Documentation/thermal/sysfs-api.txt64
2 files changed, 108 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/thermal/db8500-thermal.txt b/Documentation/devicetree/bindings/thermal/db8500-thermal.txt
new file mode 100644
index 000000000000..2e1c06fad81f
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/db8500-thermal.txt
@@ -0,0 +1,44 @@
+* ST-Ericsson DB8500 Thermal
+
+** Thermal node properties:
+
+- compatible : "stericsson,db8500-thermal";
+- reg : address range of the thermal sensor registers;
+- interrupts : interrupts generated from PRCMU;
+- interrupt-names : "IRQ_HOTMON_LOW" and "IRQ_HOTMON_HIGH";
+- num-trips : number of total trip points, this is required, set it 0 if none,
+ if greater than 0, the following properties must be defined;
+- tripN-temp : temperature of trip point N, should be in ascending order;
+- tripN-type : type of trip point N, should be one of "active" "passive" "hot"
+ "critical";
+- tripN-cdev-num : number of the cooling devices which can be bound to trip
+ point N, this is required if trip point N is defined, set it 0 if none,
+ otherwise the following cooling device names must be defined;
+- tripN-cdev-nameM : name of the No. M cooling device of trip point N;
+
+Usually the num-trips and tripN-*** are separated in board related dts files.
+
+Example:
+thermal@801573c0 {
+ compatible = "stericsson,db8500-thermal";
+ reg = <0x801573c0 0x40>;
+ interrupts = <21 0x4>, <22 0x4>;
+ interrupt-names = "IRQ_HOTMON_LOW", "IRQ_HOTMON_HIGH";
+
+ num-trips = <3>;
+
+ trip0-temp = <75000>;
+ trip0-type = "active";
+ trip0-cdev-num = <1>;
+ trip0-cdev-name0 = "thermal-cpufreq-0";
+
+ trip1-temp = <80000>;
+ trip1-type = "active";
+ trip1-cdev-num = <2>;
+ trip1-cdev-name0 = "thermal-cpufreq-0";
+ trip1-cdev-name1 = "thermal-fan";
+
+ trip2-temp = <85000>;
+ trip2-type = "critical";
+ trip2-cdev-num = <0>;
+}
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index ca1a1a34970e..88c02334e356 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -112,6 +112,29 @@ temperature) and throttle appropriate devices.
trip: indicates which trip point the cooling devices is associated with
in this thermal zone.
+1.4 Thermal Zone Parameters
+1.4.1 struct thermal_bind_params
+ This structure defines the following parameters that are used to bind
+ a zone with a cooling device for a particular trip point.
+ .cdev: The cooling device pointer
+ .weight: The 'influence' of a particular cooling device on this zone.
+ This is on a percentage scale. The sum of all these weights
+ (for a particular zone) cannot exceed 100.
+ .trip_mask:This is a bit mask that gives the binding relation between
+ this thermal zone and cdev, for a particular trip point.
+ If nth bit is set, then the cdev and thermal zone are bound
+ for trip point n.
+ .match: This call back returns success(0) if the 'tz and cdev' need to
+ be bound, as per platform data.
+1.4.2 struct thermal_zone_params
+ This structure defines the platform level parameters for a thermal zone.
+ This data, for each thermal zone should come from the platform layer.
+ This is an optional feature where some platforms can choose not to
+ provide this data.
+ .governor_name: Name of the thermal governor used for this zone
+ .num_tbps: Number of thermal_bind_params entries for this zone
+ .tbp: thermal_bind_params entries
+
2. sysfs attributes structure
RO read only value
@@ -126,6 +149,7 @@ Thermal zone device sys I/F, created once it's registered:
|---type: Type of the thermal zone
|---temp: Current temperature
|---mode: Working mode of the thermal zone
+ |---policy: Thermal governor used for this zone
|---trip_point_[0-*]_temp: Trip point temperature
|---trip_point_[0-*]_type: Trip point type
|---trip_point_[0-*]_hyst: Hysteresis value for this trip point
@@ -187,6 +211,10 @@ mode
charge of the thermal management.
RW, Optional
+policy
+ One of the various thermal governors used for a particular zone.
+ RW, Required
+
trip_point_[0-*]_temp
The temperature above which trip point will be fired.
Unit: millidegree Celsius
@@ -264,6 +292,7 @@ method, the sys I/F structure will be built like this:
|---type: acpitz
|---temp: 37000
|---mode: enabled
+ |---policy: step_wise
|---trip_point_0_temp: 100000
|---trip_point_0_type: critical
|---trip_point_1_temp: 80000
@@ -305,3 +334,38 @@ to a thermal_zone_device when it registers itself with the framework. The
event will be one of:{THERMAL_AUX0, THERMAL_AUX1, THERMAL_CRITICAL,
THERMAL_DEV_FAULT}. Notification can be sent when the current temperature
crosses any of the configured thresholds.
+
+5. Export Symbol APIs:
+
+5.1: get_tz_trend:
+This function returns the trend of a thermal zone, i.e the rate of change
+of temperature of the thermal zone. Ideally, the thermal sensor drivers
+are supposed to implement the callback. If they don't, the thermal
+framework calculated the trend by comparing the previous and the current
+temperature values.
+
+5.2:get_thermal_instance:
+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.
+
+5.3:notify_thermal_framework:
+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,
+and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
+The throttling policy is based on the configured platform data; if no
+platform data is provided, this uses the step_wise throttling policy.
+
+5.4:thermal_cdev_update:
+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
+possible.
+
+5.5:thermal_register_governor:
+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.
+
+5.6:thermal_unregister_governor:
+This function unregisters a governor from the thermal framework.