hwmon: enhance the sysfs API for power meters

Augment the documentation of the hwmon sysfs API to accomodate ACPI power
meters and the current desired behavior of power capping hardware drivers.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 56 insertions, 1 deletions

diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface
index dcbd502c8792..82def883361b 100644
--- a/Documentation/hwmon/sysfs-interface
+++ b/Documentation/hwmon/sysfs-interface
@@ -353,10 +353,20 @@ power[1-*]_average		Average power use
                                 Unit: microWatt
                                 RO
 
-power[1-*]_average_interval     Power use averaging interval
+power[1-*]_average_interval     Power use averaging interval.  A poll
+                                notification is sent to this file if the
+                                hardware changes the averaging interval.
                                 Unit: milliseconds
                                 RW
 
+power[1-*]_average_interval_max Maximum power use averaging interval
+                                Unit: milliseconds
+                                RO
+
+power[1-*]_average_interval_min Minimum power use averaging interval
+                                Unit: milliseconds
+                                RO
+
 power[1-*]_average_highest      Historical average maximum power use
                                 Unit: microWatt
                                 RO
@@ -365,6 +375,18 @@ power[1-*]_average_lowest	Historical average minimum power use
                                 Unit: microWatt
                                 RO
 
+power[1-*]_average_max          A poll notification is sent to
+                                power[1-*]_average when power use
+                                rises above this value.
+                                Unit: microWatt
+                                RW
+
+power[1-*]_average_min          A poll notification is sent to
+                                power[1-*]_average when power use
+                                sinks below this value.
+                                Unit: microWatt
+                                RW
+
 power[1-*]_input                Instantaneous power use
                                 Unit: microWatt
                                 RO
@@ -381,6 +403,39 @@ power[1-*]_reset_history	Reset input_highest, input_lowest,
                                 average_highest and average_lowest.
                                 WO
 
+power[1-*]_accuracy             Accuracy of the power meter.
+                                Unit: Percent
+                                RO
+
+power[1-*]_alarm                1 if the system is drawing more power than the
+                                cap allows; 0 otherwise.  A poll notification is
+                                sent to this file when the power use exceeds the
+                                cap.  This file only appears if the cap is known
+                                to be enforced by hardware.
+                                RO
+
+power[1-*]_cap                  If power use rises above this limit, the
+                                system should take action to reduce power use.
+                                A poll notification is sent to this file if the
+                                cap is changed by the hardware.  The *_cap
+                                files only appear if the cap is known to be
+                                enforced by hardware.
+                                Unit: microWatt
+                                RW
+
+power[1-*]_cap_hyst             Margin of hysteresis built around capping and
+                                notification.
+                                Unit: microWatt
+                                RW
+
+power[1-*]_cap_max              Maximum cap that can be set.
+                                Unit: microWatt
+                                RO
+
+power[1-*]_cap_min              Minimum cap that can be set.
+                                Unit: microWatt
+                                RO
+
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 * Energy *
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