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Diffstat (limited to 'Documentation/thermal/sysfs-api.txt')
| -rw-r--r-- | Documentation/thermal/sysfs-api.txt | 31 |
1 files changed, 31 insertions, 0 deletions
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, |