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-rw-r--r--Documentation/thermal/cpu-cooling-api.txt32
-rw-r--r--Documentation/thermal/exynos_thermal52
-rw-r--r--Documentation/thermal/sysfs-api.txt9
3 files changed, 92 insertions, 1 deletions
diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt
new file mode 100644
index 000000000000..fca24c931ec8
--- /dev/null
+++ b/Documentation/thermal/cpu-cooling-api.txt
@@ -0,0 +1,32 @@
+CPU cooling APIs How To
+===================================
+
+Written by Amit Daniel Kachhap <amit.kachhap@linaro.org>
+
+Updated: 12 May 2012
+
+Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com)
+
+0. Introduction
+
+The generic cpu cooling(freq clipping) provides registration/unregistration APIs
+to the caller. The binding of the cooling devices to the trip point is left for
+the user. The registration APIs returns the cooling device pointer.
+
+1. cpu cooling APIs
+
+1.1 cpufreq registration/unregistration APIs
+1.1.1 struct thermal_cooling_device *cpufreq_cooling_register(
+ struct cpumask *clip_cpus)
+
+ This interface function registers the cpufreq cooling device with the name
+ "thermal-cpufreq-%x". This api can support multiple instances of cpufreq
+ cooling devices.
+
+ clip_cpus: cpumask of cpus where the frequency constraints will happen.
+
+1.1.2 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
+
+ This interface function unregisters the "thermal-cpufreq-%x" cooling device.
+
+ cdev: Cooling device pointer which has to be unregistered.
diff --git a/Documentation/thermal/exynos_thermal b/Documentation/thermal/exynos_thermal
new file mode 100644
index 000000000000..2b46f67b1ccb
--- /dev/null
+++ b/Documentation/thermal/exynos_thermal
@@ -0,0 +1,52 @@
+Kernel driver exynos4_tmu
+=================
+
+Supported chips:
+* ARM SAMSUNG EXYNOS4 series of SoC
+ Prefix: 'exynos4-tmu'
+ Datasheet: Not publicly available
+
+Authors: Donggeun Kim <dg77.kim@samsung.com>
+
+Description
+-----------
+
+This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC.
+
+The chip only exposes the measured 8-bit temperature code value
+through a register.
+Temperature can be taken from the temperature code.
+There are three equations converting from temperature to temperature code.
+
+The three equations are:
+ 1. Two point trimming
+ Tc = (T - 25) * (TI2 - TI1) / (85 - 25) + TI1
+
+ 2. One point trimming
+ Tc = T + TI1 - 25
+
+ 3. No trimming
+ Tc = T + 50
+
+ Tc: Temperature code, T: Temperature,
+ TI1: Trimming info for 25 degree Celsius (stored at TRIMINFO register)
+ Temperature code measured at 25 degree Celsius which is unchanged
+ TI2: Trimming info for 85 degree Celsius (stored at TRIMINFO register)
+ Temperature code measured at 85 degree Celsius which is unchanged
+
+TMU(Thermal Management Unit) in EXYNOS4 generates interrupt
+when temperature exceeds pre-defined levels.
+The maximum number of configurable threshold is four.
+The threshold levels are defined as follows:
+ Level_0: current temperature > trigger_level_0 + threshold
+ Level_1: current temperature > trigger_level_1 + threshold
+ Level_2: current temperature > trigger_level_2 + threshold
+ Level_3: current temperature > trigger_level_3 + threshold
+
+ The threshold and each trigger_level are set
+ through the corresponding registers.
+
+When an interrupt occurs, this driver notify kernel thermal framework
+with the function exynos4_report_trigger.
+Although an interrupt condition for level_0 can be set,
+it can be used to synchronize the cooling action.
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index c087dbcf3535..ca1a1a34970e 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -84,7 +84,8 @@ temperature) and throttle appropriate devices.
1.3 interface for binding a thermal zone device with a thermal cooling device
1.3.1 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
- int trip, struct thermal_cooling_device *cdev);
+ int trip, struct thermal_cooling_device *cdev,
+ unsigned long upper, unsigned long lower);
This interface function bind a thermal cooling device to the certain trip
point of a thermal zone device.
@@ -93,6 +94,12 @@ temperature) and throttle appropriate devices.
cdev: thermal cooling device
trip: indicates which trip point the cooling devices is associated with
in this thermal zone.
+ upper:the Maximum cooling state for this trip point.
+ THERMAL_NO_LIMIT means no upper limit,
+ and the cooling device can be in max_state.
+ lower:the Minimum cooling state can be used for this trip point.
+ THERMAL_NO_LIMIT means no lower limit,
+ and the cooling device can be in cooling state 0.
1.3.2 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
int trip, struct thermal_cooling_device *cdev);