-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
yaml --- r: 267264 b: refs/heads/master c: 9d97e5c h: refs/heads/master v: v3
- Loading branch information
Donggeun Kim
authored and
Guenter Roeck
committed
Oct 24, 2011
1 parent
ed20d5e
commit ca338aa
Showing
6 changed files
with
700 additions
and
1 deletion.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -1,2 +1,2 @@ | ||
--- | ||
refs/heads/master: 5cf231a346fb80d7945aa46e90186a068a3a001b | ||
refs/heads/master: 9d97e5c81e15afaef65d00f077f863c94f750839 |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,81 @@ | ||
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 user space of | ||
one of four threshold levels for the interrupt | ||
through kobject_uevent_env and sysfs_notify functions. | ||
Although an interrupt condition for level_0 can be set, | ||
it is not notified to user space through sysfs_notify function. | ||
|
||
Sysfs Interface | ||
--------------- | ||
name name of the temperature sensor | ||
RO | ||
|
||
temp1_input temperature | ||
RO | ||
|
||
temp1_max temperature for level_1 interrupt | ||
RO | ||
|
||
temp1_crit temperature for level_2 interrupt | ||
RO | ||
|
||
temp1_emergency temperature for level_3 interrupt | ||
RO | ||
|
||
temp1_max_alarm alarm for level_1 interrupt | ||
RO | ||
|
||
temp1_crit_alarm | ||
alarm for level_2 interrupt | ||
RO | ||
|
||
temp1_emergency_alarm | ||
alarm for level_3 interrupt | ||
RO |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.