diff options
Diffstat (limited to 'Documentation/thermal')
| -rw-r--r-- | Documentation/thermal/exynos_thermal | 43 | ||||
| -rw-r--r-- | Documentation/thermal/sysfs-api.txt | 12 |
2 files changed, 46 insertions, 9 deletions
diff --git a/Documentation/thermal/exynos_thermal b/Documentation/thermal/exynos_thermal index 2b46f67..9010c44 100644 --- a/Documentation/thermal/exynos_thermal +++ b/Documentation/thermal/exynos_thermal @@ -1,17 +1,17 @@ -Kernel driver exynos4_tmu +Kernel driver exynos_tmu ================= Supported chips: -* ARM SAMSUNG EXYNOS4 series of SoC - Prefix: 'exynos4-tmu' +* ARM SAMSUNG EXYNOS4, EXYNOS5 series of SoC Datasheet: Not publicly available Authors: Donggeun Kim <dg77.kim@samsung.com> +Authors: Amit Daniel <amit.daniel@samsung.com> -Description ------------ +TMU controller Description: +--------------------------- -This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC. +This driver allows to read temperature inside SAMSUNG EXYNOS4/5 series of SoC. The chip only exposes the measured 8-bit temperature code value through a register. @@ -34,9 +34,9 @@ The three equations are: 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 +TMU(Thermal Management Unit) in EXYNOS4/5 generates interrupt when temperature exceeds pre-defined levels. -The maximum number of configurable threshold is four. +The maximum number of configurable threshold is five. The threshold levels are defined as follows: Level_0: current temperature > trigger_level_0 + threshold Level_1: current temperature > trigger_level_1 + threshold @@ -47,6 +47,31 @@ The threshold levels are defined as follows: through the corresponding registers. When an interrupt occurs, this driver notify kernel thermal framework -with the function exynos4_report_trigger. +with the function exynos_report_trigger. Although an interrupt condition for level_0 can be set, it can be used to synchronize the cooling action. + +TMU driver description: +----------------------- + +The exynos thermal driver is structured as, + + Kernel Core thermal framework + (thermal_core.c, step_wise.c, cpu_cooling.c) + ^ + | + | +TMU configuration data -------> TMU Driver <------> Exynos Core thermal wrapper +(exynos_tmu_data.c) (exynos_tmu.c) (exynos_thermal_common.c) +(exynos_tmu_data.h) (exynos_tmu.h) (exynos_thermal_common.h) + +a) TMU configuration data: This consist of TMU register offsets/bitfields + described through structure exynos_tmu_registers. Also several + other platform data (struct exynos_tmu_platform_data) members + are used to configure the TMU. +b) TMU driver: This component initialises the TMU controller and sets different + thresholds. It invokes core thermal implementation with the call + exynos_report_trigger. +c) Exynos Core thermal wrapper: This provides 3 wrapper function to use the + Kernel core thermal framework. They are exynos_unregister_thermal, + exynos_register_thermal and exynos_report_trigger. diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index a71bd5b..87519cb 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -134,6 +134,13 @@ temperature) and throttle appropriate devices. 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. + .limits: This is an array of cooling state limits. Must have exactly + 2 * thermal_zone.number_of_trip_points. It is an array consisting + of tuples <lower-state upper-state> of state limits. Each trip + will be associated with one state limit tuple when binding. + A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS> + on all trips. These limits are used when binding a cdev to a + trip point. .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 @@ -142,6 +149,11 @@ temperature) and throttle appropriate devices. 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 + .no_hwmon: a boolean to indicate if the thermal to hwmon sysfs interface + is required. when no_hwmon == false, a hwmon sysfs interface + will be created. when no_hwmon == true, nothing will be done. + In case the thermal_zone_params is NULL, the hwmon interface + will be created (for backward compatibility). .num_tbps: Number of thermal_bind_params entries for this zone .tbp: thermal_bind_params entries |
