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Diffstat (limited to 'Documentation/thermal/exynos_thermal')
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diff --git a/Documentation/thermal/exynos_thermal b/Documentation/thermal/exynos_thermal deleted file mode 100644 index 9010c4416967..000000000000 --- a/Documentation/thermal/exynos_thermal +++ /dev/null @@ -1,77 +0,0 @@ -Kernel driver exynos_tmu -================= - -Supported chips: -* 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> - -TMU controller Description: ---------------------------- - -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. -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 EXYNOS4/5 generates interrupt -when temperature exceeds pre-defined levels. -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 - 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 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. |