thermal: sysfs-api.txt - document passive attribute for thermal zones

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index 895337f8c6ba..a87dc277a5ca 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -199,6 +199,15 @@ cdev[0-*]_trip_point
         point.
         RO, Optional
 
+passive
+        Attribute is only present for zones in which the passive cooling
+        policy is not supported by native thermal driver. Default is zero
+        and can be set to a temperature (in millidegrees) to enable a
+        passive trip point for the zone. Activation is done by polling with
+        an interval of 1 second.
+        Unit: millidegrees Celsius
+        RW, Optional
+
 *****************************
 * Cooling device attributes *
 *****************************