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-rw-r--r--Documentation/acpi/method-customizing.txt66
-rw-r--r--Documentation/feature-removal-schedule.txt19
-rw-r--r--Documentation/laptops/thinkpad-acpi.txt114
-rw-r--r--Documentation/thermal/sysfs-api.txt1
4 files changed, 150 insertions, 50 deletions
diff --git a/Documentation/acpi/method-customizing.txt b/Documentation/acpi/method-customizing.txt
new file mode 100644
index 00000000000..e628cd23ca8
--- /dev/null
+++ b/Documentation/acpi/method-customizing.txt
@@ -0,0 +1,66 @@
+Linux ACPI Custom Control Method How To
+=======================================
+
+Written by Zhang Rui <rui.zhang@intel.com>
+
+
+Linux supports customizing ACPI control methods at runtime.
+
+Users can use this to
+1. override an existing method which may not work correctly,
+ or just for debugging purposes.
+2. insert a completely new method in order to create a missing
+ method such as _OFF, _ON, _STA, _INI, etc.
+For these cases, it is far simpler to dynamically install a single
+control method rather than override the entire DSDT, because kernel
+rebuild/reboot is not needed and test result can be got in minutes.
+
+Note: Only ACPI METHOD can be overridden, any other object types like
+ "Device", "OperationRegion", are not recognized.
+Note: The same ACPI control method can be overridden for many times,
+ and it's always the latest one that used by Linux/kernel.
+
+1. override an existing method
+ a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT,
+ just run "cat /sys/firmware/acpi/tables/DSDT > /tmp/dsdt.dat"
+ b) disassemble the table by running "iasl -d dsdt.dat".
+ c) rewrite the ASL code of the method and save it in a new file,
+ d) package the new file (psr.asl) to an ACPI table format.
+ Here is an example of a customized \_SB._AC._PSR method,
+
+ DefinitionBlock ("", "SSDT", 1, "", "", 0x20080715)
+ {
+ External (ACON)
+
+ Method (\_SB_.AC._PSR, 0, NotSerialized)
+ {
+ Store ("In AC _PSR", Debug)
+ Return (ACON)
+ }
+ }
+ Note that the full pathname of the method in ACPI namespace
+ should be used.
+ And remember to use "External" to declare external objects.
+ e) assemble the file to generate the AML code of the method.
+ e.g. "iasl psr.asl" (psr.aml is generated as a result)
+ f) mount debugfs by "mount -t debugfs none /sys/kernel/debug"
+ g) override the old method via the debugfs by running
+ "cat /tmp/psr.aml > /sys/kernel/debug/acpi/custom_method"
+
+2. insert a new method
+ This is easier than overriding an existing method.
+ We just need to create the ASL code of the method we want to
+ insert and then follow the step c) ~ g) in section 1.
+
+3. undo your changes
+ The "undo" operation is not supported for a new inserted method
+ right now, i.e. we can not remove a method currently.
+ For an overrided method, in order to undo your changes, please
+ save a copy of the method original ASL code in step c) section 1,
+ and redo step c) ~ g) to override the method with the original one.
+
+
+Note: We can use a kernel with multiple custom ACPI method running,
+ But each individual write to debugfs can implement a SINGLE
+ method override. i.e. if we want to insert/override multiple
+ ACPI methods, we need to redo step c) ~ g) for multiple times.
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 21ab9357326..870d190fe61 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -474,3 +474,22 @@ Why: Obsoleted by the adt7475 driver.
Who: Jean Delvare <khali@linux-fr.org>
---------------------------
+What: Support for lcd_switch and display_get in asus-laptop driver
+When: March 2010
+Why: These two features use non-standard interfaces. There are the
+ only features that really need multiple path to guess what's
+ the right method name on a specific laptop.
+
+ Removing them will allow to remove a lot of code an significantly
+ clean the drivers.
+
+ This will affect the backlight code which won't be able to know
+ if the backlight is on or off. The platform display file will also be
+ write only (like the one in eeepc-laptop).
+
+ This should'nt affect a lot of user because they usually know
+ when their display is on or off.
+
+Who: Corentin Chary <corentin.chary@gmail.com>
+
+----------------------------
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index aafcaa63419..169091f75e6 100644
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -1,7 +1,7 @@
ThinkPad ACPI Extras Driver
- Version 0.23
- April 10th, 2009
+ Version 0.24
+ December 11th, 2009
Borislav Deianov <borislav@users.sf.net>
Henrique de Moraes Holschuh <hmh@hmh.eng.br>
@@ -460,6 +460,8 @@ event code Key Notes
For Lenovo ThinkPads with a new
BIOS, it has to be handled either
by the ACPI OSI, or by userspace.
+ The driver does the right thing,
+ never mess with this.
0x1011 0x10 FN+END Brightness down. See brightness
up for details.
@@ -582,46 +584,15 @@ with hotkey_report_mode.
Brightness hotkey notes:
-These are the current sane choices for brightness key mapping in
-thinkpad-acpi:
+Don't mess with the brightness hotkeys in a Thinkpad. If you want
+notifications for OSD, use the sysfs backlight class event support.
-For IBM and Lenovo models *without* ACPI backlight control (the ones on
-which thinkpad-acpi will autoload its backlight interface by default,
-and on which ACPI video does not export a backlight interface):
-
-1. Don't enable or map the brightness hotkeys in thinkpad-acpi, as
- these older firmware versions unfortunately won't respect the hotkey
- mask for brightness keys anyway, and always reacts to them. This
- usually work fine, unless X.org drivers are doing something to block
- the BIOS. In that case, use (3) below. This is the default mode of
- operation.
-
-2. Enable the hotkeys, but map them to something else that is NOT
- KEY_BRIGHTNESS_UP/DOWN or any other keycode that would cause
- userspace to try to change the backlight level, and use that as an
- on-screen-display hint.
-
-3. IF AND ONLY IF X.org drivers find a way to block the firmware from
- automatically changing the brightness, enable the hotkeys and map
- them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN, and feed that to
- something that calls xbacklight. thinkpad-acpi will not be able to
- change brightness in that case either, so you should disable its
- backlight interface.
-
-For Lenovo models *with* ACPI backlight control:
-
-1. Load up ACPI video and use that. ACPI video will report ACPI
- events for brightness change keys. Do not mess with thinkpad-acpi
- defaults in this case. thinkpad-acpi should not have anything to do
- with backlight events in a scenario where ACPI video is loaded:
- brightness hotkeys must be disabled, and the backlight interface is
- to be kept disabled as well. This is the default mode of operation.
-
-2. Do *NOT* load up ACPI video, enable the hotkeys in thinkpad-acpi,
- and map them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN. Process
- these keys on userspace somehow (e.g. by calling xbacklight).
- The driver will do this automatically if it detects that ACPI video
- has been disabled.
+The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
+automatically for the cases were userspace has to do something to
+implement brightness changes. When you override these events, you will
+either fail to handle properly the ThinkPads that require explicit
+action to change backlight brightness, or the ThinkPads that require
+that no action be taken to work properly.
Bluetooth
@@ -1121,25 +1092,61 @@ WARNING:
its level up and down at every change.
-Volume control -- /proc/acpi/ibm/volume
----------------------------------------
+Volume control
+--------------
+
+procfs: /proc/acpi/ibm/volume
+ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC"
+
+NOTE: by default, the volume control interface operates in read-only
+mode, as it is supposed to be used for on-screen-display purposes.
+The read/write mode can be enabled through the use of the
+"volume_control=1" module parameter.
-This feature allows volume control on ThinkPad models which don't have
-a hardware volume knob. The available commands are:
+NOTE: distros are urged to not enable volume_control by default, this
+should be done by the local admin only. The ThinkPad UI is for the
+console audio control to be done through the volume keys only, and for
+the desktop environment to just provide on-screen-display feedback.
+Software volume control should be done only in the main AC97/HDA
+mixer.
+
+This feature allows volume control on ThinkPad models with a digital
+volume knob (when available, not all models have it), as well as
+mute/unmute control. The available commands are:
echo up >/proc/acpi/ibm/volume
echo down >/proc/acpi/ibm/volume
echo mute >/proc/acpi/ibm/volume
+ echo unmute >/proc/acpi/ibm/volume
echo 'level <level>' >/proc/acpi/ibm/volume
-The <level> number range is 0 to 15 although not all of them may be
+The <level> number range is 0 to 14 although not all of them may be
distinct. The unmute the volume after the mute command, use either the
-up or down command (the level command will not unmute the volume).
+up or down command (the level command will not unmute the volume), or
+the unmute command.
+
The current volume level and mute state is shown in the file.
-The ALSA mixer interface to this feature is still missing, but patches
-to add it exist. That problem should be addressed in the not so
-distant future.
+You can use the volume_capabilities parameter to tell the driver
+whether your thinkpad has volume control or mute-only control:
+volume_capabilities=1 for mixers with mute and volume control,
+volume_capabilities=2 for mixers with only mute control.
+
+If the driver misdetects the capabilities for your ThinkPad model,
+please report this to ibm-acpi-devel@lists.sourceforge.net, so that we
+can update the driver.
+
+There are two strategies for volume control. To select which one
+should be used, use the volume_mode module parameter: volume_mode=1
+selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing
+(so that volume/mute changes are remembered across shutdown/reboot).
+
+The driver will operate in volume_mode=3 by default. If that does not
+work well on your ThinkPad model, please report this to
+ibm-acpi-devel@lists.sourceforge.net.
+
+The driver supports the standard ALSA module parameters. If the ALSA
+mixer is disabled, the driver will disable all volume functionality.
Fan control and monitoring: fan speed, fan enable/disable
@@ -1405,6 +1412,7 @@ to enable more than one output class, just add their values.
0x0008 HKEY event interface, hotkeys
0x0010 Fan control
0x0020 Backlight brightness
+ 0x0040 Audio mixer/volume control
There is also a kernel build option to enable more debugging
information, which may be necessary to debug driver problems.
@@ -1465,3 +1473,9 @@ Sysfs interface changelog:
and it is always able to disable hot keys. Very old
thinkpads are properly supported. hotkey_bios_mask
is deprecated and marked for removal.
+
+0x020600: Marker for backlight change event support.
+
+0x020700: Support for mute-only mixers.
+ Volume control in read-only mode by default.
+ Marker for ALSA mixer support.
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index a87dc277a5c..cb3d15bc1ae 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -206,6 +206,7 @@ passive
passive trip point for the zone. Activation is done by polling with
an interval of 1 second.
Unit: millidegrees Celsius
+ Valid values: 0 (disabled) or greater than 1000
RW, Optional
*****************************