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diff --git a/Documentation/ibm-acpi.txt b/Documentation/ibm-acpi.txt new file mode 100644 index 000000000000..c437b1aeff55 --- /dev/null +++ b/Documentation/ibm-acpi.txt @@ -0,0 +1,474 @@ + IBM ThinkPad ACPI Extras Driver + + Version 0.8 + 8 November 2004 + + Borislav Deianov <borislav@users.sf.net> + http://ibm-acpi.sf.net/ + + +This is a Linux ACPI driver for the IBM ThinkPad laptops. It aims to +support various features of these laptops which are accessible through +the ACPI framework but not otherwise supported by the generic Linux +ACPI drivers. + + +Status +------ + +The features currently supported are the following (see below for +detailed description): + + - Fn key combinations + - Bluetooth enable and disable + - video output switching, expansion control + - ThinkLight on and off + - limited docking and undocking + - UltraBay eject + - Experimental: CMOS control + - Experimental: LED control + - Experimental: ACPI sounds + +A compatibility table by model and feature is maintained on the web +site, http://ibm-acpi.sf.net/. I appreciate any success or failure +reports, especially if they add to or correct the compatibility table. +Please include the following information in your report: + + - ThinkPad model name + - a copy of your DSDT, from /proc/acpi/dsdt + - which driver features work and which don't + - the observed behavior of non-working features + +Any other comments or patches are also more than welcome. + + +Installation +------------ + +If you are compiling this driver as included in the Linux kernel +sources, simply enable the CONFIG_ACPI_IBM option (Power Management / +ACPI / IBM ThinkPad Laptop Extras). The rest of this section describes +how to install this driver when downloaded from the web site. + +First, you need to get a kernel with ACPI support up and running. +Please refer to http://acpi.sourceforge.net/ for help with this +step. How successful you will be depends a lot on you ThinkPad model, +the kernel you are using and any additional patches applied. The +kernel provided with your distribution may not be good enough. I +needed to compile a 2.6.7 kernel with the 20040715 ACPI patch to get +ACPI working reliably on my ThinkPad X40. Old ThinkPad models may not +be supported at all. + +Assuming you have the basic ACPI support working (e.g. you can see the +/proc/acpi directory), follow the following steps to install this +driver: + + - unpack the archive: + + tar xzvf ibm-acpi-x.y.tar.gz; cd ibm-acpi-x.y + + - compile the driver: + + make + + - install the module in your kernel modules directory: + + make install + + - load the module: + + modprobe ibm_acpi + +After loading the module, check the "dmesg" output for any error messages. + + +Features +-------- + +The driver creates the /proc/acpi/ibm directory. There is a file under +that directory for each feature described below. Note that while the +driver is still in the alpha stage, the exact proc file format and +commands supported by the various features is guaranteed to change +frequently. + +Driver Version -- /proc/acpi/ibm/driver +-------------------------------------- + +The driver name and version. No commands can be written to this file. + +Hot Keys -- /proc/acpi/ibm/hotkey +--------------------------------- + +Without this driver, only the Fn-F4 key (sleep button) generates an +ACPI event. With the driver loaded, the hotkey feature enabled and the +mask set (see below), the various hot keys generate ACPI events in the +following format: + + ibm/hotkey HKEY 00000080 0000xxxx + +The last four digits vary depending on the key combination pressed. +All labeled Fn-Fx key combinations generate distinct events. In +addition, the lid microswitch and some docking station buttons may +also generate such events. + +The following commands can be written to this file: + + echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature + echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature + echo 0xffff > /proc/acpi/ibm/hotkey -- enable all possible hot keys + echo 0x0000 > /proc/acpi/ibm/hotkey -- disable all possible hot keys + ... any other 4-hex-digit mask ... + echo reset > /proc/acpi/ibm/hotkey -- restore the original mask + +The bit mask allows some control over which hot keys generate ACPI +events. Not all bits in the mask can be modified. Not all bits that +can be modified do anything. Not all hot keys can be individually +controlled by the mask. Most recent ThinkPad models honor the +following bits (assuming the hot keys feature has been enabled): + + key bit behavior when set behavior when unset + + Fn-F3 always generates ACPI event + Fn-F4 always generates ACPI event + Fn-F5 0010 generate ACPI event enable/disable Bluetooth + Fn-F7 0040 generate ACPI event switch LCD and external display + Fn-F8 0080 generate ACPI event expand screen or none + Fn-F9 0100 generate ACPI event none + Fn-F12 always generates ACPI event + +Some models do not support all of the above. For example, the T30 does +not support Fn-F5 and Fn-F9. Other models do not support the mask at +all. On those models, hot keys cannot be controlled individually. + +Note that enabling ACPI events for some keys prevents their default +behavior. For example, if events for Fn-F5 are enabled, that key will +no longer enable/disable Bluetooth by itself. This can still be done +from an acpid handler for the ibm/hotkey event. + +Note also that not all Fn key combinations are supported through +ACPI. For example, on the X40, the brightness, volume and "Access IBM" +buttons do not generate ACPI events even with this driver. They *can* +be used through the "ThinkPad Buttons" utility, see +http://www.nongnu.org/tpb/ + +Bluetooth -- /proc/acpi/ibm/bluetooth +------------------------------------- + +This feature shows the presence and current state of a Bluetooth +device. If Bluetooth is installed, the following commands can be used: + + echo enable > /proc/acpi/ibm/bluetooth + echo disable > /proc/acpi/ibm/bluetooth + +Video output control -- /proc/acpi/ibm/video +-------------------------------------------- + +This feature allows control over the devices used for video output - +LCD, CRT or DVI (if available). The following commands are available: + + echo lcd_enable > /proc/acpi/ibm/video + echo lcd_disable > /proc/acpi/ibm/video + echo crt_enable > /proc/acpi/ibm/video + echo crt_disable > /proc/acpi/ibm/video + echo dvi_enable > /proc/acpi/ibm/video + echo dvi_disable > /proc/acpi/ibm/video + echo auto_enable > /proc/acpi/ibm/video + echo auto_disable > /proc/acpi/ibm/video + echo expand_toggle > /proc/acpi/ibm/video + echo video_switch > /proc/acpi/ibm/video + +Each video output device can be enabled or disabled individually. +Reading /proc/acpi/ibm/video shows the status of each device. + +Automatic video switching can be enabled or disabled. When automatic +video switching is enabled, certain events (e.g. opening the lid, +docking or undocking) cause the video output device to change +automatically. While this can be useful, it also causes flickering +and, on the X40, video corruption. By disabling automatic switching, +the flickering or video corruption can be avoided. + +The video_switch command cycles through the available video outputs +(it sumulates the behavior of Fn-F7). + +Video expansion can be toggled through this feature. This controls +whether the display is expanded to fill the entire LCD screen when a +mode with less than full resolution is used. Note that the current +video expansion status cannot be determined through this feature. + +Note that on many models (particularly those using Radeon graphics +chips) the X driver configures the video card in a way which prevents +Fn-F7 from working. This also disables the video output switching +features of this driver, as it uses the same ACPI methods as +Fn-F7. Video switching on the console should still work. + +ThinkLight control -- /proc/acpi/ibm/light +------------------------------------------ + +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: + + echo on > /proc/acpi/ibm/light + echo off > /proc/acpi/ibm/light + +Docking / Undocking -- /proc/acpi/ibm/dock +------------------------------------------ + +Docking and undocking (e.g. with the X4 UltraBase) requires some +actions to be taken by the operating system to safely make or break +the electrical connections with the dock. + +The docking feature of this driver generates the following ACPI events: + + ibm/dock GDCK 00000003 00000001 -- eject request + ibm/dock GDCK 00000003 00000002 -- undocked + ibm/dock GDCK 00000000 00000003 -- docked + +NOTE: These events will only be generated if the laptop was docked +when originally booted. This is due to the current lack of support for +hot plugging of devices in the Linux ACPI framework. If the laptop was +booted while not in the dock, the following message is shown in the +logs: "ibm_acpi: dock device not present". No dock-related events are +generated but the dock and undock commands described below still +work. They can be executed manually or triggered by Fn key +combinations (see the example acpid configuration files included in +the driver tarball package available on the web site). + +When the eject request button on the dock is pressed, the first event +above is generated. The handler for this event should issue the +following command: + + echo undock > /proc/acpi/ibm/dock + +After the LED on the dock goes off, it is safe to eject the laptop. +Note: if you pressed this key by mistake, go ahead and eject the +laptop, then dock it back in. Otherwise, the dock may not function as +expected. + +When the laptop is docked, the third event above is generated. The +handler for this event should issue the following command to fully +enable the dock: + + echo dock > /proc/acpi/ibm/dock + +The contents of the /proc/acpi/ibm/dock file shows the current status +of the dock, as provided by the ACPI framework. + +The docking support in this driver does not take care of enabling or +disabling any other devices you may have attached to the dock. For +example, a CD drive plugged into the UltraBase needs to be disabled or +enabled separately. See the provided example acpid configuration files +for how this can be accomplished. + +There is no support yet for PCI devices that may be attached to a +docking station, e.g. in the ThinkPad Dock II. The driver currently +does not recognize, enable or disable such devices. This means that +the only docking stations currently supported are the X-series +UltraBase docks and "dumb" port replicators like the Mini Dock (the +latter don't need any ACPI support, actually). + +UltraBay Eject -- /proc/acpi/ibm/bay +------------------------------------ + +Inserting or ejecting an UltraBay device requires some actions to be +taken by the operating system to safely make or break the electrical +connections with the device. + +This feature generates the following ACPI events: + + ibm/bay MSTR 00000003 00000000 -- eject request + ibm/bay MSTR 00000001 00000000 -- eject lever inserted + +NOTE: These events will only be generated if the UltraBay was present +when the laptop was originally booted (on the X series, the UltraBay +is in the dock, so it may not be present if the laptop was undocked). +This is due to the current lack of support for hot plugging of devices +in the Linux ACPI framework. If the laptop was booted without the +UltraBay, the following message is shown in the logs: "ibm_acpi: bay +device not present". No bay-related events are generated but the eject +command described below still works. It can be executed manually or +triggered by a hot key combination. + +Sliding the eject lever generates the first event shown above. The +handler for this event should take whatever actions are necessary to +shut down the device in the UltraBay (e.g. call idectl), then issue +the following command: + + echo eject > /proc/acpi/ibm/bay + +After the LED on the UltraBay goes off, it is safe to pull out the +device. + +When the eject lever is inserted, the second event above is +generated. The handler for this event should take whatever actions are +necessary to enable the UltraBay device (e.g. call idectl). + +The contents of the /proc/acpi/ibm/bay file shows the current status +of the UltraBay, as provided by the ACPI framework. + +Experimental Features +--------------------- + +The following features are marked experimental because using them +involves guessing the correct values of some parameters. Guessing +incorrectly may have undesirable effects like crashing your +ThinkPad. USE THESE WITH CAUTION! To activate them, you'll need to +supply the experimental=1 parameter when loading the module. + +Experimental: CMOS control - /proc/acpi/ibm/cmos +------------------------------------------------ + +This feature is used internally by the ACPI firmware to control the +ThinkLight on most newer ThinkPad models. It appears that it can also +control LCD brightness, sounds volume and more, but only on some +models. + +The commands are non-negative integer numbers: + + echo 0 >/proc/acpi/ibm/cmos + echo 1 >/proc/acpi/ibm/cmos + echo 2 >/proc/acpi/ibm/cmos + ... + +The range of numbers which are used internally by various models is 0 +to 21, but it's possible that numbers outside this range have +interesting behavior. Here is the behavior on the X40 (tpb is the +ThinkPad Buttons utility): + + 0 - no effect but tpb reports "Volume down" + 1 - no effect but tpb reports "Volume up" + 2 - no effect but tpb reports "Mute on" + 3 - simulate pressing the "Access IBM" button + 4 - LCD brightness up + 5 - LCD brightness down + 11 - toggle screen expansion + 12 - ThinkLight on + 13 - ThinkLight off + 14 - no effect but tpb reports ThinkLight status change + +If you try this feature, please send me a report similar to the +above. On models which allow control of LCD brightness or sound +volume, I'd like to provide this functionality in an user-friendly +way, but first I need a way to identify the models which this is +possible. + +Experimental: LED control - /proc/acpi/ibm/LED +---------------------------------------------- + +Some of the LED indicators can be controlled through this feature. 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> parameter is a non-negative integer. The range of LED +numbers used internally by various models is 0 to 7 but it's possible +that numbers outside this range are also valid. Here is the mapping on +the X40: + + 0 - power + 1 - battery (orange) + 2 - battery (green) + 3 - UltraBase + 4 - UltraBay + 7 - standby + +All of the above can be turned on and off and can be made to blink. + +If you try this feature, please send me a report similar to the +above. I'd like to provide this functionality in an user-friendly way, +but first I need to identify the which numbers correspond to which +LEDs on various models. + +Experimental: ACPI sounds - /proc/acpi/ibm/beep +----------------------------------------------- + +The BEEP method is used internally by the ACPI firmware to provide +audible alerts in various situtation. This feature allows the same +sounds to be triggered manually. + +The commands are non-negative integer numbers: + + echo 0 >/proc/acpi/ibm/beep + echo 1 >/proc/acpi/ibm/beep + echo 2 >/proc/acpi/ibm/beep + ... + +The range of numbers which are used internally by various models is 0 +to 17, but it's possible that numbers outside this range are also +valid. Here is the behavior on the X40: + + 2 - two beeps, pause, third beep + 3 - single beep + 4 - "unable" + 5 - single beep + 6 - "AC/DC" + 7 - high-pitched beep + 9 - three short beeps + 10 - very long beep + 12 - low-pitched beep + +(I've only been able to identify a couple of them). + +If you try this feature, please send me a report similar to the +above. I'd like to provide this functionality in an user-friendly way, +but first I need to identify the which numbers correspond to which +sounds on various models. + + +Multiple Command, Module Parameters +----------------------------------- + +Multiple commands can be written to the proc files in one shot by +separating them with commas, for example: + + echo enable,0xffff > /proc/acpi/ibm/hotkey + echo lcd_disable,crt_enable > /proc/acpi/ibm/video + +Commands can also be specified when loading the ibm_acpi module, for +example: + + modprobe ibm_acpi hotkey=enable,0xffff video=auto_disable + + +Example Configuration +--------------------- + +The ACPI support in the kernel is intended to be used in conjunction +with a user-space daemon, acpid. The configuration files for this +daemon control what actions are taken in response to various ACPI +events. An example set of configuration files are included in the +config/ directory of the tarball package available on the web +site. Note that these are provided for illustration purposes only and +may need to be adapted to your particular setup. + +The following utility scripts are used by the example action +scripts (included with ibm-acpi for completeness): + + /usr/local/sbin/idectl -- from the hdparm source distribution, + see http://www.ibiblio.org/pub/Linux/system/hardware + /usr/local/sbin/laptop_mode -- from the Linux kernel source + distribution, see Documentation/laptop-mode.txt + /sbin/service -- comes with Redhat/Fedora distributions + +Toan T Nguyen <ntt@control.uchicago.edu> has written a SuSE powersave +script for the X20, included in config/usr/sbin/ibm_hotkeys_X20 + +Henrik Brix Andersen <brix@gentoo.org> has written a Gentoo ACPI event +handler script for the X31. You can get the latest version from +http://dev.gentoo.org/~brix/files/x31.sh + +David Schweikert <dws@ee.eth.ch> has written an alternative blank.sh +script which works on Debian systems, included in +configs/etc/acpi/actions/blank-debian.sh + + +TODO +---- + +I'd like to implement the following features but haven't yet found the +time and/or I don't yet know how to implement them: + +- UltraBay floppy drive support + |
