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diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index bb9a0a53e76b..911399730c1c 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -255,6 +255,7 @@ temperature) and throttle appropriate devices.
2. sysfs attributes structure
RO read only value
+WO write only value
RW read/write value
Thermal sysfs attributes will be represented under /sys/class/thermal.
@@ -286,6 +287,11 @@ Thermal cooling device sys I/F, created once it's registered:
|---type: Type of the cooling device(processor/fan/...)
|---max_state: Maximum cooling state of the cooling device
|---cur_state: Current cooling state of the cooling device
+ |---stats: Directory containing cooling device's statistics
+ |---stats/reset: Writing any value resets the statistics
+ |---stats/time_in_state_ms: Time (msec) spent in various cooling states
+ |---stats/total_trans: Total number of times cooling state is changed
+ |---stats/trans_table: Cooing state transition table
Then next two dynamic attributes are created/removed in pairs. They represent
@@ -490,6 +496,31 @@ cur_state
- cur_state == max_state means the maximum cooling.
RW, Required
+stats/reset
+ Writing any value resets the cooling device's statistics.
+ WO, Required
+
+stats/time_in_state_ms:
+ The amount of time spent by the cooling device in various cooling
+ states. The output will have "<state> <time>" pair in each line, which
+ will mean this cooling device spent <time> msec of time at <state>.
+ Output will have one line for each of the supported states. usertime
+ units here is 10mS (similar to other time exported in /proc).
+ RO, Required
+
+stats/total_trans:
+ A single positive value showing the total number of times the state of a
+ cooling device is changed.
+ RO, Required
+
+stats/trans_table:
+ This gives fine grained information about all the cooling state
+ transitions. The cat output here is a two dimensional matrix, where an
+ entry <i,j> (row i, column j) represents the number of transitions from
+ State_i to State_j. If the transition table is bigger than PAGE_SIZE,
+ reading this will return an -EFBIG error.
+ RO, Required
+
3. A simple implementation
ACPI thermal zone may support multiple trip points like critical, hot,