diff options
author | Amit Daniel Kachhap <amit.kachhap@linaro.org> | 2012-08-16 07:41:41 -0400 |
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committer | Zhang Rui <rui.zhang@intel.com> | 2012-09-24 02:44:38 -0400 |
commit | c48cbba6fee3587bdfe77ef850a1a0aa30a2a60f (patch) | |
tree | 43a342f501ce99e0b44b5a9346dd3edcf1b255d9 /Documentation/hwmon | |
parent | 023614183768a7ac62898bded5ec6c0c9fecbdd9 (diff) |
hwmon: exynos4: move thermal sensor driver to driver/thermal directory
This movement is needed because the hwmon entries and corresponding sysfs
interface is a duplicate of utilities already provided by
driver/thermal/thermal_sys.c. The goal is to place it in thermal folder
and add necessary functions to use the in-kernel thermal interfaces.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: SangWook Ju <sw.ju@samsung.com>
Cc: Durgadoss <durgadoss.r@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Diffstat (limited to 'Documentation/hwmon')
-rw-r--r-- | Documentation/hwmon/exynos4_tmu | 81 |
1 files changed, 0 insertions, 81 deletions
diff --git a/Documentation/hwmon/exynos4_tmu b/Documentation/hwmon/exynos4_tmu deleted file mode 100644 index c3c6b41db607..000000000000 --- a/Documentation/hwmon/exynos4_tmu +++ /dev/null | |||
@@ -1,81 +0,0 @@ | |||
1 | Kernel driver exynos4_tmu | ||
2 | ================= | ||
3 | |||
4 | Supported chips: | ||
5 | * ARM SAMSUNG EXYNOS4 series of SoC | ||
6 | Prefix: 'exynos4-tmu' | ||
7 | Datasheet: Not publicly available | ||
8 | |||
9 | Authors: Donggeun Kim <dg77.kim@samsung.com> | ||
10 | |||
11 | Description | ||
12 | ----------- | ||
13 | |||
14 | This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC. | ||
15 | |||
16 | The chip only exposes the measured 8-bit temperature code value | ||
17 | through a register. | ||
18 | Temperature can be taken from the temperature code. | ||
19 | There are three equations converting from temperature to temperature code. | ||
20 | |||
21 | The three equations are: | ||
22 | 1. Two point trimming | ||
23 | Tc = (T - 25) * (TI2 - TI1) / (85 - 25) + TI1 | ||
24 | |||
25 | 2. One point trimming | ||
26 | Tc = T + TI1 - 25 | ||
27 | |||
28 | 3. No trimming | ||
29 | Tc = T + 50 | ||
30 | |||
31 | Tc: Temperature code, T: Temperature, | ||
32 | TI1: Trimming info for 25 degree Celsius (stored at TRIMINFO register) | ||
33 | Temperature code measured at 25 degree Celsius which is unchanged | ||
34 | TI2: Trimming info for 85 degree Celsius (stored at TRIMINFO register) | ||
35 | Temperature code measured at 85 degree Celsius which is unchanged | ||
36 | |||
37 | TMU(Thermal Management Unit) in EXYNOS4 generates interrupt | ||
38 | when temperature exceeds pre-defined levels. | ||
39 | The maximum number of configurable threshold is four. | ||
40 | The threshold levels are defined as follows: | ||
41 | Level_0: current temperature > trigger_level_0 + threshold | ||
42 | Level_1: current temperature > trigger_level_1 + threshold | ||
43 | Level_2: current temperature > trigger_level_2 + threshold | ||
44 | Level_3: current temperature > trigger_level_3 + threshold | ||
45 | |||
46 | The threshold and each trigger_level are set | ||
47 | through the corresponding registers. | ||
48 | |||
49 | When an interrupt occurs, this driver notify user space of | ||
50 | one of four threshold levels for the interrupt | ||
51 | through kobject_uevent_env and sysfs_notify functions. | ||
52 | Although an interrupt condition for level_0 can be set, | ||
53 | it is not notified to user space through sysfs_notify function. | ||
54 | |||
55 | Sysfs Interface | ||
56 | --------------- | ||
57 | name name of the temperature sensor | ||
58 | RO | ||
59 | |||
60 | temp1_input temperature | ||
61 | RO | ||
62 | |||
63 | temp1_max temperature for level_1 interrupt | ||
64 | RO | ||
65 | |||
66 | temp1_crit temperature for level_2 interrupt | ||
67 | RO | ||
68 | |||
69 | temp1_emergency temperature for level_3 interrupt | ||
70 | RO | ||
71 | |||
72 | temp1_max_alarm alarm for level_1 interrupt | ||
73 | RO | ||
74 | |||
75 | temp1_crit_alarm | ||
76 | alarm for level_2 interrupt | ||
77 | RO | ||
78 | |||
79 | temp1_emergency_alarm | ||
80 | alarm for level_3 interrupt | ||
81 | RO | ||