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+EXYNOS EMULATION MODE
+Copyright (C) 2012 Samsung Electronics
+Written by Jonghwa Lee <email@example.com>
+Exynos 4x12 (4212, 4412) and 5 series provide emulation mode for thermal management unit.
+Thermal emulation mode supports software debug for TMU's operation. User can set temperature
+manually with software code and TMU will read current temperature from user value not from
+Enabling CONFIG_EXYNOS_THERMAL_EMUL option will make this support in available.
+When it's enabled, sysfs node will be created under
+/sys/bus/platform/devices/'exynos device name'/ with name of 'emulation'.
+The sysfs node, 'emulation', will contain value 0 for the initial state. When you input any
+temperature you want to update to sysfs node, it automatically enable emulation mode and
+current temperature will be changed into it.
+(Exynos also supports user changable delay time which would be used to delay of
+ changing temperature. However, this node only uses same delay of real sensing time, 938us.)
+Exynos emulation mode requires synchronous of value changing and enabling. It means when you
+want to update the any value of delay or next temperature, then you have to enable emulation
+mode at the same time. (Or you have to keep the mode enabling.) If you don't, it fails to
+change the value to updated one and just use last succeessful value repeatedly. That's why
+this node gives users the right to change termerpature only. Just one interface makes it more
+simply to use.
+Disabling emulation mode only requires writing value 0 to sysfs node.
+TEMP 120 |
+ 100 |
+ 80 |
+ | +-----------
+ 60 | | |
+ | +-------------| |
+ 40 | | | |
+ | | | |
+ 20 | | | +----------
+ | | | | |
+ 0 |______________|_____________|__________|__________|_________
+ A A A A TIME
+ |<----->| |<----->| |<----->| |
+ | 938us | | | | | |
+emulation : 0 50 | 70 | 20 | 0
+current temp : sensor 50 70 20 sensor