docs: thermal: convert to ReST

Rename the thermal documentation files to ReST, add an
index for them and adjust in order to produce a nice html
output via the Sphinx build system.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

1 files changed, 90 insertions, 0 deletions

diff --git a/Documentation/thermal/exynos_thermal.rst b/Documentation/thermal/exynos_thermal.rst
new file mode 100644
index 000000000000..5bd556566c70
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+++ b/Documentation/thermal/exynos_thermal.rst
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+========================
+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.