Merge branch 'core/iter-div' of git://git.kernel.org/pub/scm/linux/kernel/git/tip...

[firefly-linux-kernel-4.4.55.git] / Documentation / laptops / thinkpad-acpi.txt

diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index a41bc893f8d6755866a82c71bc310ec708f9d656..64b3f146e4b09aa4d2cd312e97689f9eba503347 100644 (file)
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -1,7 +1,7 @@
                     ThinkPad ACPI Extras Driver
 
-                            Version 0.19
-                         January 06th, 2008
+                            Version 0.20
+                          April 09th, 2008
 
                Borislav Deianov <borislav@users.sf.net>
              Henrique de Moraes Holschuh <hmh@hmh.eng.br>
@@ -503,7 +503,7 @@ generate input device EV_KEY events.
 In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
 events for switches:
 
-SW_RADIO       T60 and later hardare rfkill rocker switch
+SW_RFKILL_ALL  T60 and later hardare rfkill rocker switch
 SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
 
 Non hot-key ACPI HKEY event map:
@@ -693,16 +693,31 @@ while others are still having problems. For more information:
 
 https://bugs.freedesktop.org/show_bug.cgi?id=2000
 
-ThinkLight control -- /proc/acpi/ibm/light
-------------------------------------------
+ThinkLight control
+------------------
+
+procfs: /proc/acpi/ibm/light
+sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
 
-The current status of the ThinkLight can be found in this file. A few
-models which do not make the status available will show it as
-"unknown". The available commands are:
+procfs notes:
+
+The ThinkLight status can be read and set through the procfs interface.  A
+few models which do not make the status available will show the ThinkLight
+status as "unknown". The available commands are:
 
        echo on  > /proc/acpi/ibm/light
        echo off > /proc/acpi/ibm/light
 
+sysfs notes:
+
+The ThinkLight sysfs interface is documented by the LED class
+documentation, in Documentation/leds-class.txt.  The ThinkLight LED name
+is "tpacpi::thinklight".
+
+Due to limitations in the sysfs LED class, if the status of the thinklight
+cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
+It is impossible to know if the status returned through sysfs is valid.
+
 Docking / undocking -- /proc/acpi/ibm/dock
 ------------------------------------------
 
@@ -861,28 +876,63 @@ The cmos command interface is prone to firmware split-brain problems, as
 in newer ThinkPads it is just a compatibility layer.  Do not use it, it is
 exported just as a debug tool.
 
-LED control -- /proc/acpi/ibm/led
----------------------------------
+LED control
+-----------
 
-Some of the LED indicators can be controlled through this feature. The
-available commands are:
+procfs: /proc/acpi/ibm/led
+sysfs attributes: as per LED class, see below for names
 
-       echo '<led number> on' >/proc/acpi/ibm/led
-       echo '<led number> off' >/proc/acpi/ibm/led
-       echo '<led number> blink' >/proc/acpi/ibm/led
+Some of the LED indicators can be controlled through this feature.  On
+some older ThinkPad models, it is possible to query the status of the
+LED indicators as well.  Newer ThinkPads cannot query the real status
+of the LED indicators.
+
+procfs notes:
 
-The <led number> range is 0 to 7. The set of LEDs that can be
-controlled varies from model to model. Here is the mapping on the X40:
+The available commands are:
+
+       echo '<LED number> on' >/proc/acpi/ibm/led
+       echo '<LED number> off' >/proc/acpi/ibm/led
+       echo '<LED number> blink' >/proc/acpi/ibm/led
+
+The <LED number> range is 0 to 7. The set of LEDs that can be
+controlled varies from model to model. Here is the common ThinkPad
+mapping:
 
        0 - power
        1 - battery (orange)
        2 - battery (green)
-       3 - UltraBase
+       3 - UltraBase/dock
        4 - UltraBay
+       5 - UltraBase battery slot
+       6 - (unknown)
        7 - standby
 
 All of the above can be turned on and off and can be made to blink.
 
+sysfs notes:
+
+The ThinkPad LED sysfs interface is described in detail by the LED class
+documentation, in Documentation/leds-class.txt.
+
+The leds are named (in LED ID order, from 0 to 7):
+"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
+"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
+"tpacpi::unknown_led", "tpacpi::standby".
+
+Due to limitations in the sysfs LED class, if the status of the LED
+indicators cannot be read due to an error, thinkpad-acpi will report it as
+a brightness of zero (same as LED off).
+
+If the thinkpad firmware doesn't support reading the current status,
+trying to read the current LED brightness will just return whatever
+brightness was last written to that attribute.
+
+These LEDs can blink using hardware acceleration.  To request that a
+ThinkPad indicator LED should blink in hardware accelerated mode, use the
+"timer" trigger, and leave the delay_on and delay_off parameters set to
+zero (to request hardware acceleration autodetection).
+
 ACPI sounds -- /proc/acpi/ibm/beep
 ----------------------------------