Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 54 insertions, 0 deletions

diff --git a/Documentation/hwmon/acpi_power_meter.rst b/Documentation/hwmon/acpi_power_meter.rst
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+Kernel driver power_meter
+=========================
+
+This driver talks to ACPI 4.0 power meters.
+
+Supported systems:
+
+  * Any recent system with ACPI 4.0.
+
+    Prefix: 'power_meter'
+
+    Datasheet: https://uefi.org/specifications, section 10.4.
+
+Author: Darrick J. Wong
+
+Description
+-----------
+
+This driver implements sensor reading support for the power meters exposed in
+the ACPI 4.0 spec (Chapter 10.4).  These devices have a simple set of
+features--a power meter that returns average power use over a configurable
+interval, an optional capping mechanism, and a couple of trip points.  The
+sysfs interface conforms with the specification outlined in the "Power" section
+of Documentation/hwmon/sysfs-interface.rst.
+
+Special Features
+----------------
+
+The `power[1-*]_is_battery` knob indicates if the power supply is a battery.
+Both `power[1-*]_average_{min,max}` must be set before the trip points will work.
+When both of them are set, an ACPI event will be broadcast on the ACPI netlink
+socket and a poll notification will be sent to the appropriate
+`power[1-*]_average` sysfs file.
+
+The `power[1-*]_{model_number, serial_number, oem_info}` fields display
+arbitrary strings that ACPI provides with the meter.  The measures/ directory
+contains symlinks to the devices that this meter measures.
+
+Some computers have the ability to enforce a power cap in hardware.  If this is
+the case, the `power[1-*]_cap` and related sysfs files will appear.  When the
+average power consumption exceeds the cap, an ACPI event will be broadcast on
+the netlink event socket and a poll notification will be sent to the
+appropriate `power[1-*]_alarm` file to indicate that capping has begun, and the
+hardware has taken action to reduce power consumption.  Most likely this will
+result in reduced performance.
+
+There are a few other ACPI notifications that can be sent by the firmware.  In
+all cases the ACPI event will be broadcast on the ACPI netlink event socket as
+well as sent as a poll notification to a sysfs file.  The events are as
+follows:
+
+`power[1-*]_cap` will be notified if the firmware changes the power cap.
+`power[1-*]_interval` will be notified if the firmware changes the averaging
+interval.