1 ThinkPad ACPI Extras Driver
6 Borislav Deianov <borislav@users.sf.net>
7 Henrique de Moraes Holschuh <hmh@hmh.eng.br>
8 http://ibm-acpi.sf.net/
11 This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It
12 supports various features of these laptops which are accessible
13 through the ACPI and ACPI EC framework, but not otherwise fully
14 supported by the generic Linux ACPI drivers.
16 This driver used to be named ibm-acpi until kernel 2.6.21 and release
17 0.13-20070314. It used to be in the drivers/acpi tree, but it was
18 moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel
19 2.6.22, and release 0.14.
25 The features currently supported are the following (see below for
26 detailed description):
29 - Bluetooth enable and disable
30 - video output switching, expansion control
31 - ThinkLight on and off
32 - limited docking and undocking
38 - Experimental: embedded controller register dump
39 - LCD brightness control
41 - Fan control and monitoring: fan speed, fan enable/disable
42 - Experimental: WAN enable and disable
44 A compatibility table by model and feature is maintained on the web
45 site, http://ibm-acpi.sf.net/. I appreciate any success or failure
46 reports, especially if they add to or correct the compatibility table.
47 Please include the following information in your report:
50 - a copy of your DSDT, from /proc/acpi/dsdt
51 - a copy of the output of dmidecode, with serial numbers
53 - which driver features work and which don't
54 - the observed behavior of non-working features
56 Any other comments or patches are also more than welcome.
62 If you are compiling this driver as included in the Linux kernel
63 sources, simply enable the CONFIG_THINKPAD_ACPI option, and optionally
64 enable the CONFIG_THINKPAD_ACPI_BAY option if you want the
65 thinkpad-specific bay functionality.
70 The driver exports two different interfaces to userspace, which can be
71 used to access the features it provides. One is a legacy procfs-based
72 interface, which will be removed at some time in the distant future.
73 The other is a new sysfs-based interface which is not complete yet.
75 The procfs interface creates the /proc/acpi/ibm directory. There is a
76 file under that directory for each feature it supports. The procfs
77 interface is mostly frozen, and will change very little if at all: it
78 will not be extended to add any new functionality in the driver, instead
79 all new functionality will be implemented on the sysfs interface.
81 The sysfs interface tries to blend in the generic Linux sysfs subsystems
82 and classes as much as possible. Since some of these subsystems are not
83 yet ready or stabilized, it is expected that this interface will change,
84 and any and all userspace programs must deal with it.
87 Notes about the sysfs interface:
89 Unlike what was done with the procfs interface, correctness when talking
90 to the sysfs interfaces will be enforced, as will correctness in the
91 thinkpad-acpi's implementation of sysfs interfaces.
93 Also, any bugs in the thinkpad-acpi sysfs driver code or in the
94 thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
95 maximum correctness, even if that means changing an interface in
96 non-compatible ways. As these interfaces mature both in the kernel and
97 in thinkpad-acpi, such changes should become quite rare.
99 Applications interfacing to the thinkpad-acpi sysfs interfaces must
100 follow all sysfs guidelines and correctly process all errors (the sysfs
101 interface makes extensive use of errors). File descriptors and open /
102 close operations to the sysfs inodes must also be properly implemented.
104 The version of thinkpad-acpi's sysfs interface is exported by the driver
105 as a driver attribute (see below).
107 Sysfs driver attributes are on the driver's sysfs attribute space,
108 for 2.6.20 this is /sys/bus/platform/drivers/thinkpad-acpi/.
110 Sysfs device attributes are on the driver's sysfs attribute space,
111 for 2.6.20 this is /sys/devices/platform/thinkpad-acpi/.
116 procfs: /proc/acpi/ibm/driver
117 sysfs driver attribute: version
119 The driver name and version. No commands can be written to this file.
121 Sysfs interface version
122 -----------------------
124 sysfs driver attribute: interface_version
126 Version of the thinkpad-acpi sysfs interface, as an unsigned long
127 (output in hex format: 0xAAAABBCC), where:
128 AAAA - major revision
132 The sysfs interface version changelog for the driver can be found at the
133 end of this document. Changes to the sysfs interface done by the kernel
134 subsystems are not documented here, nor are they tracked by this
137 Changes to the thinkpad-acpi sysfs interface are only considered
138 non-experimental when they are submitted to Linux mainline, at which
139 point the changes in this interface are documented and interface_version
140 may be updated. If you are using any thinkpad-acpi features not yet
141 sent to mainline for merging, you do so on your own risk: these features
142 may disappear, or be implemented in a different and incompatible way by
143 the time they are merged in Linux mainline.
145 Changes that are backwards-compatible by nature (e.g. the addition of
146 attributes that do not change the way the other attributes work) do not
147 always warrant an update of interface_version. Therefore, one must
148 expect that an attribute might not be there, and deal with it properly
149 (an attribute not being there *is* a valid way to make it clear that a
150 feature is not available in sysfs).
155 procfs: /proc/acpi/ibm/hotkey
156 sysfs device attribute: hotkey_*
158 In a ThinkPad, the ACPI HKEY handler is responsible for comunicating
159 some important events and also keyboard hot key presses to the operating
160 system. Enabling the hotkey functionality of thinkpad-acpi signals the
161 firmware that such a driver is present, and modifies how the ThinkPad
162 firmware will behave in many situations.
164 When the hotkey feature is enabled and the hot key mask is set (see
165 below), the various hot keys either generate ACPI events in the
168 ibm/hotkey HKEY 00000080 0000xxxx
170 or events over the input layer. The input layer support accepts the
171 standard IOCTLs to remap the keycodes assigned to each hotkey.
173 When the input device is open, the driver will suppress any ACPI hot key
174 events that get translated into a meaningful input layer event, in order
175 to avoid sending duplicate events to userspace. Hot keys that are
176 mapped to KEY_RESERVED in the keymap are not translated, and will always
177 generate an ACPI ibm/hotkey HKEY event, and no input layer events.
179 The hot key bit mask allows some control over which hot keys generate
180 events. If a key is "masked" (bit set to 0 in the mask), the firmware
181 will handle it. If it is "unmasked", it signals the firmware that
182 thinkpad-acpi would prefer to handle it, if the firmware would be so
183 kind to allow it (and it often doesn't!).
185 Not all bits in the mask can be modified. Not all bits that can be
186 modified do anything. Not all hot keys can be individually controlled
187 by the mask. Some models do not support the mask at all, and in those
188 models, hot keys cannot be controlled individually. The behaviour of
189 the mask is, therefore, higly dependent on the ThinkPad model.
191 Note that unmasking some keys prevents their default behavior. For
192 example, if Fn+F5 is unmasked, that key will no longer enable/disable
195 Note also that not all Fn key combinations are supported through ACPI.
196 For example, on the X40, the brightness, volume and "Access IBM" buttons
197 do not generate ACPI events even with this driver. They *can* be used
198 through the "ThinkPad Buttons" utility, see http://www.nongnu.org/tpb/
202 The following commands can be written to the /proc/acpi/ibm/hotkey file:
204 echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature
205 echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature
206 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
207 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
208 ... any other 8-hex-digit mask ...
209 echo reset > /proc/acpi/ibm/hotkey -- restore the original mask
214 Returns the status of the hot keys feature when
215 thinkpad-acpi was loaded. Upon module unload, the hot
216 key feature status will be restored to this value.
218 0: hot keys were disabled
219 1: hot keys were enabled (unusual)
222 Returns the hot keys mask when thinkpad-acpi was loaded.
223 Upon module unload, the hot keys mask will be restored
227 Enables/disables the hot keys feature, and reports
228 current status of the hot keys feature.
230 0: disables the hot keys feature / feature disabled
231 1: enables the hot keys feature / feature enabled
234 bit mask to enable driver-handling and ACPI event
235 generation for each hot key (see above). Returns the
236 current status of the hot keys mask, and allows one to
240 bit mask that should enable event reporting for all
241 supported hot keys, when echoed to hotkey_mask above.
242 Unless you know which events need to be handled
243 passively (because the firmware *will* handle them
244 anyway), do *not* use hotkey_all_mask. Use
245 hotkey_recommended_mask, instead. You have been warned.
247 hotkey_recommended_mask:
248 bit mask that should enable event reporting for all
249 supported hot keys, except those which are always
250 handled by the firmware anyway. Echo it to
251 hotkey_mask above, to use.
254 if the ThinkPad has a hardware radio switch, this
255 attribute will read 0 if the switch is in the "radios
256 disabled" postition, and 1 if the switch is in the
257 "radios enabled" position.
261 A Hot key is mapped to a single input layer EV_KEY event, possibly
262 followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
263 code. An EV_SYN event will always be generated to mark the end of the
266 Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
267 used as a helper to remap keys, only. They are particularly useful when
268 remapping KEY_UNKNOWN keys.
270 The events are available in an input device, with the following id:
273 vendor: 0x1014 (PCI_VENDOR_ID_IBM)
274 product: 0x5054 ("TP")
277 The version will have its LSB incremented if the keymap changes in a
278 backwards-compatible way. The MSB shall always be 0x41 for this input
279 device. If the MSB is not 0x41, do not use the device as described in
280 this section, as it is either something else (e.g. another input device
281 exported by a thinkpad driver, such as HDAPS) or its functionality has
282 been changed in a non-backwards compatible way.
284 Adding other event types for other functionalities shall be considered a
285 backwards-compatible change for this input device.
287 Thinkpad-acpi Hot Key event map (version 0x4101):
295 0x1003 0x02 FN+F3 Many models always report this
296 hot key, even with hot keys
297 disabled or with Fn+F3 masked
300 0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
301 semanthics, i.e. sleep-to-RAM).
302 It is always generate some kind
303 of event, either the hot key
304 event or a ACPI sleep button
305 event. The firmware may
306 refuse to generate further FN+F4
307 key presses until a S3 or S4 ACPI
308 sleep cycle is performed or some
311 0x1005 0x04 FN+F5 Radio. Enables/disables
312 the internal BlueTooth hardware
313 and W-WAN card if left in control
314 of the firmware. Does not affect
319 0x1007 0x06 FN+F7 Video output cycle.
320 Do you feel lucky today?
326 0x100C 0x0B FN+F12 Sleep to disk. You are always
327 supposed to handle it yourself,
328 either through the ACPI event,
329 or through a hotkey event.
330 The firmware may refuse to
331 generate further FN+F4 key
332 press events until a S3 or S4
333 ACPI sleep cycle is performed,
336 0x100D 0x0C FN+BACKSPACE -
337 0x100E 0x0D FN+INSERT -
338 0x100F 0x0E FN+DELETE -
340 0x1010 0x0F FN+HOME Brightness up. This key is
341 always handled by the firmware,
342 even when unmasked. Just leave
344 0x1011 0x10 FN+END Brightness down. This key is
345 always handled by the firmware,
346 even when unmasked. Just leave
348 0x1012 0x11 FN+PGUP Thinklight toggle. This key is
349 always handled by the firmware,
352 0x1013 0x12 FN+PGDOWN -
354 0x1014 0x13 FN+SPACE Zoom key
356 0x1015 0x14 VOLUME UP Internal mixer volume up. This
357 key is always handled by the
358 firmware, even when unmasked.
359 0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
360 key is always handled by the
361 firmware, even when unmasked.
362 0x1017 0x16 MUTE Mute internal mixer. This
363 key is always handled by the
364 firmware, even when unmasked.
366 0x1018 0x17 THINKPAD Thinkpad/Access IBM/Lenovo key
372 The ThinkPad firmware does not allow one to differentiate when most hot
373 keys are pressed or released (either that, or we don't know how to, yet).
374 For these keys, the driver generates a set of events for a key press and
375 immediately issues the same set of events for a key release. It is
376 unknown by the driver if the ThinkPad firmware triggered these events on
377 hot key press or release, but the firmware will do it for either one, not
380 If a key is mapped to KEY_RESERVED, it generates no input events at all,
381 and it may generate a legacy thinkpad-acpi ACPI hotkey event.
383 If a key is mapped to KEY_UNKNOWN, it generates an input event that
384 includes an scan code, and it may also generate a legacy thinkpad-acpi
387 If a key is mapped to anything else, it will only generate legacy
388 thinkpad-acpi ACPI hotkey events if nobody has opened the input device.
390 Non hot-key ACPI HKEY event map:
393 0x7000 Radio Switch may have changed state
399 procfs: /proc/acpi/ibm/bluetooth
400 sysfs device attribute: bluetooth_enable
402 This feature shows the presence and current state of a ThinkPad
403 Bluetooth device in the internal ThinkPad CDC slot.
407 If Bluetooth is installed, the following commands can be used:
409 echo enable > /proc/acpi/ibm/bluetooth
410 echo disable > /proc/acpi/ibm/bluetooth
414 If the Bluetooth CDC card is installed, it can be enabled /
415 disabled through the "bluetooth_enable" thinkpad-acpi device
416 attribute, and its current status can also be queried.
419 0: disables Bluetooth / Bluetooth is disabled
420 1: enables Bluetooth / Bluetooth is enabled.
422 Note: this interface will be probably be superseeded by the
423 generic rfkill class, so it is NOT to be considered stable yet.
425 Video output control -- /proc/acpi/ibm/video
426 --------------------------------------------
428 This feature allows control over the devices used for video output -
429 LCD, CRT or DVI (if available). The following commands are available:
431 echo lcd_enable > /proc/acpi/ibm/video
432 echo lcd_disable > /proc/acpi/ibm/video
433 echo crt_enable > /proc/acpi/ibm/video
434 echo crt_disable > /proc/acpi/ibm/video
435 echo dvi_enable > /proc/acpi/ibm/video
436 echo dvi_disable > /proc/acpi/ibm/video
437 echo auto_enable > /proc/acpi/ibm/video
438 echo auto_disable > /proc/acpi/ibm/video
439 echo expand_toggle > /proc/acpi/ibm/video
440 echo video_switch > /proc/acpi/ibm/video
442 Each video output device can be enabled or disabled individually.
443 Reading /proc/acpi/ibm/video shows the status of each device.
445 Automatic video switching can be enabled or disabled. When automatic
446 video switching is enabled, certain events (e.g. opening the lid,
447 docking or undocking) cause the video output device to change
448 automatically. While this can be useful, it also causes flickering
449 and, on the X40, video corruption. By disabling automatic switching,
450 the flickering or video corruption can be avoided.
452 The video_switch command cycles through the available video outputs
453 (it simulates the behavior of Fn-F7).
455 Video expansion can be toggled through this feature. This controls
456 whether the display is expanded to fill the entire LCD screen when a
457 mode with less than full resolution is used. Note that the current
458 video expansion status cannot be determined through this feature.
460 Note that on many models (particularly those using Radeon graphics
461 chips) the X driver configures the video card in a way which prevents
462 Fn-F7 from working. This also disables the video output switching
463 features of this driver, as it uses the same ACPI methods as
464 Fn-F7. Video switching on the console should still work.
466 UPDATE: There's now a patch for the X.org Radeon driver which
467 addresses this issue. Some people are reporting success with the patch
468 while others are still having problems. For more information:
470 https://bugs.freedesktop.org/show_bug.cgi?id=2000
472 ThinkLight control -- /proc/acpi/ibm/light
473 ------------------------------------------
475 The current status of the ThinkLight can be found in this file. A few
476 models which do not make the status available will show it as
477 "unknown". The available commands are:
479 echo on > /proc/acpi/ibm/light
480 echo off > /proc/acpi/ibm/light
482 Docking / undocking -- /proc/acpi/ibm/dock
483 ------------------------------------------
485 Docking and undocking (e.g. with the X4 UltraBase) requires some
486 actions to be taken by the operating system to safely make or break
487 the electrical connections with the dock.
489 The docking feature of this driver generates the following ACPI events:
491 ibm/dock GDCK 00000003 00000001 -- eject request
492 ibm/dock GDCK 00000003 00000002 -- undocked
493 ibm/dock GDCK 00000000 00000003 -- docked
495 NOTE: These events will only be generated if the laptop was docked
496 when originally booted. This is due to the current lack of support for
497 hot plugging of devices in the Linux ACPI framework. If the laptop was
498 booted while not in the dock, the following message is shown in the
501 Mar 17 01:42:34 aero kernel: thinkpad_acpi: dock device not present
503 In this case, no dock-related events are generated but the dock and
504 undock commands described below still work. They can be executed
505 manually or triggered by Fn key combinations (see the example acpid
506 configuration files included in the driver tarball package available
509 When the eject request button on the dock is pressed, the first event
510 above is generated. The handler for this event should issue the
513 echo undock > /proc/acpi/ibm/dock
515 After the LED on the dock goes off, it is safe to eject the laptop.
516 Note: if you pressed this key by mistake, go ahead and eject the
517 laptop, then dock it back in. Otherwise, the dock may not function as
520 When the laptop is docked, the third event above is generated. The
521 handler for this event should issue the following command to fully
524 echo dock > /proc/acpi/ibm/dock
526 The contents of the /proc/acpi/ibm/dock file shows the current status
527 of the dock, as provided by the ACPI framework.
529 The docking support in this driver does not take care of enabling or
530 disabling any other devices you may have attached to the dock. For
531 example, a CD drive plugged into the UltraBase needs to be disabled or
532 enabled separately. See the provided example acpid configuration files
533 for how this can be accomplished.
535 There is no support yet for PCI devices that may be attached to a
536 docking station, e.g. in the ThinkPad Dock II. The driver currently
537 does not recognize, enable or disable such devices. This means that
538 the only docking stations currently supported are the X-series
539 UltraBase docks and "dumb" port replicators like the Mini Dock (the
540 latter don't need any ACPI support, actually).
542 UltraBay eject -- /proc/acpi/ibm/bay
543 ------------------------------------
545 Inserting or ejecting an UltraBay device requires some actions to be
546 taken by the operating system to safely make or break the electrical
547 connections with the device.
549 This feature generates the following ACPI events:
551 ibm/bay MSTR 00000003 00000000 -- eject request
552 ibm/bay MSTR 00000001 00000000 -- eject lever inserted
554 NOTE: These events will only be generated if the UltraBay was present
555 when the laptop was originally booted (on the X series, the UltraBay
556 is in the dock, so it may not be present if the laptop was undocked).
557 This is due to the current lack of support for hot plugging of devices
558 in the Linux ACPI framework. If the laptop was booted without the
559 UltraBay, the following message is shown in the logs:
561 Mar 17 01:42:34 aero kernel: thinkpad_acpi: bay device not present
563 In this case, no bay-related events are generated but the eject
564 command described below still works. It can be executed manually or
565 triggered by a hot key combination.
567 Sliding the eject lever generates the first event shown above. The
568 handler for this event should take whatever actions are necessary to
569 shut down the device in the UltraBay (e.g. call idectl), then issue
570 the following command:
572 echo eject > /proc/acpi/ibm/bay
574 After the LED on the UltraBay goes off, it is safe to pull out the
577 When the eject lever is inserted, the second event above is
578 generated. The handler for this event should take whatever actions are
579 necessary to enable the UltraBay device (e.g. call idectl).
581 The contents of the /proc/acpi/ibm/bay file shows the current status
582 of the UltraBay, as provided by the ACPI framework.
584 EXPERIMENTAL warm eject support on the 600e/x, A22p and A3x (To use
585 this feature, you need to supply the experimental=1 parameter when
588 These models do not have a button near the UltraBay device to request
589 a hot eject but rather require the laptop to be put to sleep
590 (suspend-to-ram) before the bay device is ejected or inserted).
591 The sequence of steps to eject the device is as follows:
593 echo eject > /proc/acpi/ibm/bay
594 put the ThinkPad to sleep
597 cat /proc/acpi/ibm/bay should show that the drive was removed
599 On the A3x, both the UltraBay 2000 and UltraBay Plus devices are
600 supported. Use "eject2" instead of "eject" for the second bay.
602 Note: the UltraBay eject support on the 600e/x, A22p and A3x is
603 EXPERIMENTAL and may not work as expected. USE WITH CAUTION!
608 procfs: /proc/acpi/ibm/cmos
609 sysfs device attribute: cmos_command
611 This feature is mostly used internally by the ACPI firmware to keep the legacy
612 CMOS NVRAM bits in sync with the current machine state, and to record this
613 state so that the ThinkPad will retain such settings across reboots.
615 Some of these commands actually perform actions in some ThinkPad models, but
616 this is expected to disappear more and more in newer models. As an example, in
617 a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
618 real, but commands 0 to 2 don't control the mixer anymore (they have been
619 phased out) and just update the NVRAM.
621 The range of valid cmos command numbers is 0 to 21, but not all have an
622 effect and the behavior varies from model to model. Here is the behavior
623 on the X40 (tpb is the ThinkPad Buttons utility):
625 0 - Related to "Volume down" key press
626 1 - Related to "Volume up" key press
627 2 - Related to "Mute on" key press
628 3 - Related to "Access IBM" key press
629 4 - Related to "LCD brightness up" key pess
630 5 - Related to "LCD brightness down" key press
631 11 - Related to "toggle screen expansion" key press/function
632 12 - Related to "ThinkLight on"
633 13 - Related to "ThinkLight off"
634 14 - Related to "ThinkLight" key press (toggle thinklight)
636 The cmos command interface is prone to firmware split-brain problems, as
637 in newer ThinkPads it is just a compatibility layer. Do not use it, it is
638 exported just as a debug tool.
640 LED control -- /proc/acpi/ibm/led
641 ---------------------------------
643 Some of the LED indicators can be controlled through this feature. The
644 available commands are:
646 echo '<led number> on' >/proc/acpi/ibm/led
647 echo '<led number> off' >/proc/acpi/ibm/led
648 echo '<led number> blink' >/proc/acpi/ibm/led
650 The <led number> range is 0 to 7. The set of LEDs that can be
651 controlled varies from model to model. Here is the mapping on the X40:
660 All of the above can be turned on and off and can be made to blink.
662 ACPI sounds -- /proc/acpi/ibm/beep
663 ----------------------------------
665 The BEEP method is used internally by the ACPI firmware to provide
666 audible alerts in various situations. This feature allows the same
667 sounds to be triggered manually.
669 The commands are non-negative integer numbers:
671 echo <number> >/proc/acpi/ibm/beep
673 The valid <number> range is 0 to 17. Not all numbers trigger sounds
674 and the sounds vary from model to model. Here is the behavior on the
677 0 - stop a sound in progress (but use 17 to stop 16)
678 2 - two beeps, pause, third beep ("low battery")
680 4 - high, followed by low-pitched beep ("unable")
682 6 - very high, followed by high-pitched beep ("AC/DC")
683 7 - high-pitched beep
684 9 - three short beeps
686 12 - low-pitched beep
687 15 - three high-pitched beeps repeating constantly, stop with 0
688 16 - one medium-pitched beep repeating constantly, stop with 17
694 procfs: /proc/acpi/ibm/thermal
695 sysfs device attributes: (hwmon) temp*_input
697 Most ThinkPads include six or more separate temperature sensors but
698 only expose the CPU temperature through the standard ACPI methods.
699 This feature shows readings from up to eight different sensors on older
700 ThinkPads, and it has experimental support for up to sixteen different
701 sensors on newer ThinkPads.
703 EXPERIMENTAL: The 16-sensors feature is marked EXPERIMENTAL because the
704 implementation directly accesses hardware registers and may not work as
705 expected. USE WITH CAUTION! To use this feature, you need to supply the
706 experimental=1 parameter when loading the module. When EXPERIMENTAL
707 mode is enabled, reading the first 8 sensors on newer ThinkPads will
708 also use an new experimental thermal sensor access mode.
710 For example, on the X40, a typical output may be:
711 temperatures: 42 42 45 41 36 -128 33 -128
713 EXPERIMENTAL: On the T43/p, a typical output may be:
714 temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
716 The mapping of thermal sensors to physical locations varies depending on
717 system-board model (and thus, on ThinkPad model).
719 http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
720 tries to track down these locations for various models.
722 Most (newer?) models seem to follow this pattern:
725 2: (depends on model)
726 3: (depends on model)
728 5: Main battery: main sensor
729 6: Bay battery: main sensor
730 7: Main battery: secondary sensor
731 8: Bay battery: secondary sensor
732 9-15: (depends on model)
734 For the R51 (source: Thomas Gruber):
738 For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
739 http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
740 2: System board, left side (near PCMCIA slot), reported as HDAPS temp
742 9: MCH (northbridge) to DRAM Bus
743 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
745 11: Power regulator, underside of system board, below F2 key
747 The A31 has a very atypical layout for the thermal sensors
748 (source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
750 2: Main Battery: main sensor
752 4: Bay Battery: main sensor
755 7: Main Battery: secondary sensor
756 8: Bay Battery: secondary sensor
760 Readings from sensors that are not available return -128.
761 No commands can be written to this file.
764 Sensors that are not available return the ENXIO error. This
765 status may change at runtime, as there are hotplug thermal
766 sensors, like those inside the batteries and docks.
768 thinkpad-acpi thermal sensors are reported through the hwmon
769 subsystem, and follow all of the hwmon guidelines at
773 EXPERIMENTAL: Embedded controller register dump -- /proc/acpi/ibm/ecdump
774 ------------------------------------------------------------------------
776 This feature is marked EXPERIMENTAL because the implementation
777 directly accesses hardware registers and may not work as expected. USE
778 WITH CAUTION! To use this feature, you need to supply the
779 experimental=1 parameter when loading the module.
781 This feature dumps the values of 256 embedded controller
782 registers. Values which have changed since the last time the registers
783 were dumped are marked with a star:
785 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
786 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
787 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
788 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
789 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
790 EC 0x30: 01 07 1a 00 30 04 00 00 *85 00 00 10 00 50 00 00
791 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
792 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 *bc *02 *bc
793 EC 0x60: *02 *bc *02 00 00 00 00 00 00 00 00 00 00 00 00 00
794 EC 0x70: 00 00 00 00 00 12 30 40 *24 *26 *2c *27 *20 80 *1f 80
795 EC 0x80: 00 00 00 06 *37 *0e 03 00 00 00 0e 07 00 00 00 00
796 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
797 EC 0xa0: *ff 09 ff 09 ff ff *64 00 *00 *00 *a2 41 *ff *ff *e0 00
798 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
799 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
800 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
801 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
802 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
804 This feature can be used to determine the register holding the fan
805 speed on some models. To do that, do the following:
807 - make sure the battery is fully charged
808 - make sure the fan is running
809 - run 'cat /proc/acpi/ibm/ecdump' several times, once per second or so
811 The first step makes sure various charging-related values don't
812 vary. The second ensures that the fan-related values do vary, since
813 the fan speed fluctuates a bit. The third will (hopefully) mark the
814 fan register with a star:
816 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
817 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
818 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
819 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
820 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
821 EC 0x30: 01 07 1a 00 30 04 00 00 85 00 00 10 00 50 00 00
822 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
823 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 bc 02 bc
824 EC 0x60: 02 bc 02 00 00 00 00 00 00 00 00 00 00 00 00 00
825 EC 0x70: 00 00 00 00 00 12 30 40 24 27 2c 27 21 80 1f 80
826 EC 0x80: 00 00 00 06 *be 0d 03 00 00 00 0e 07 00 00 00 00
827 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
828 EC 0xa0: ff 09 ff 09 ff ff 64 00 00 00 a2 41 ff ff e0 00
829 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
830 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
831 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
832 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
833 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
835 Another set of values that varies often is the temperature
836 readings. Since temperatures don't change vary fast, you can take
837 several quick dumps to eliminate them.
839 You can use a similar method to figure out the meaning of other
840 embedded controller registers - e.g. make sure nothing else changes
841 except the charging or discharging battery to determine which
842 registers contain the current battery capacity, etc. If you experiment
843 with this, do send me your results (including some complete dumps with
844 a description of the conditions when they were taken.)
846 LCD brightness control
847 ----------------------
849 procfs: /proc/acpi/ibm/brightness
850 sysfs backlight device "thinkpad_screen"
852 This feature allows software control of the LCD brightness on ThinkPad
853 models which don't have a hardware brightness slider.
855 It has some limitations: the LCD backlight cannot be actually turned on or off
856 by this interface, and in many ThinkPad models, the "dim while on battery"
857 functionality will be enabled by the BIOS when this interface is used, and
858 cannot be controlled.
860 The backlight control has eight levels, ranging from 0 to 7. Some of the
861 levels may not be distinct.
865 The available commands are:
867 echo up >/proc/acpi/ibm/brightness
868 echo down >/proc/acpi/ibm/brightness
869 echo 'level <level>' >/proc/acpi/ibm/brightness
873 The interface is implemented through the backlight sysfs class, which is poorly
874 documented at this time.
876 Locate the thinkpad_screen device under /sys/class/backlight, and inside it
877 there will be the following attributes:
880 Reads the maximum brightness the hardware can be set to.
881 The minimum is always zero.
884 Reads what brightness the screen is set to at this instant.
887 Writes request the driver to change brightness to the given
888 value. Reads will tell you what brightness the driver is trying
889 to set the display to when "power" is set to zero and the display
890 has not been dimmed by a kernel power management event.
893 power management mode, where 0 is "display on", and 1 to 3 will
894 dim the display backlight to brightness level 0 because
895 thinkpad-acpi cannot really turn the backlight off. Kernel
896 power management events can temporarily increase the current
897 power management level, i.e. they can dim the display.
900 Volume control -- /proc/acpi/ibm/volume
901 ---------------------------------------
903 This feature allows volume control on ThinkPad models which don't have
904 a hardware volume knob. The available commands are:
906 echo up >/proc/acpi/ibm/volume
907 echo down >/proc/acpi/ibm/volume
908 echo mute >/proc/acpi/ibm/volume
909 echo 'level <level>' >/proc/acpi/ibm/volume
911 The <level> number range is 0 to 15 although not all of them may be
912 distinct. The unmute the volume after the mute command, use either the
913 up or down command (the level command will not unmute the volume).
914 The current volume level and mute state is shown in the file.
916 Fan control and monitoring: fan speed, fan enable/disable
917 ---------------------------------------------------------
919 procfs: /proc/acpi/ibm/fan
920 sysfs device attributes: (hwmon) fan_input, pwm1, pwm1_enable
922 NOTE NOTE NOTE: fan control operations are disabled by default for
923 safety reasons. To enable them, the module parameter "fan_control=1"
924 must be given to thinkpad-acpi.
926 This feature attempts to show the current fan speed, control mode and
927 other fan data that might be available. The speed is read directly
928 from the hardware registers of the embedded controller. This is known
929 to work on later R, T, X and Z series ThinkPads but may show a bogus
930 value on other models.
934 Most ThinkPad fans work in "levels" at the firmware interface. Level 0
935 stops the fan. The higher the level, the higher the fan speed, although
936 adjacent levels often map to the same fan speed. 7 is the highest
937 level, where the fan reaches the maximum recommended speed.
939 Level "auto" means the EC changes the fan level according to some
940 internal algorithm, usually based on readings from the thermal sensors.
942 There is also a "full-speed" level, also known as "disengaged" level.
943 In this level, the EC disables the speed-locked closed-loop fan control,
944 and drives the fan as fast as it can go, which might exceed hardware
945 limits, so use this level with caution.
947 The fan usually ramps up or down slowly from one speed to another, and
948 it is normal for the EC to take several seconds to react to fan
949 commands. The full-speed level may take up to two minutes to ramp up to
950 maximum speed, and in some ThinkPads, the tachometer readings go stale
951 while the EC is transitioning to the full-speed level.
953 WARNING WARNING WARNING: do not leave the fan disabled unless you are
954 monitoring all of the temperature sensor readings and you are ready to
955 enable it if necessary to avoid overheating.
957 An enabled fan in level "auto" may stop spinning if the EC decides the
958 ThinkPad is cool enough and doesn't need the extra airflow. This is
959 normal, and the EC will spin the fan up if the varios thermal readings
962 On the X40, this seems to depend on the CPU and HDD temperatures.
963 Specifically, the fan is turned on when either the CPU temperature
964 climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
965 fan is turned off when the CPU temperature drops to 49 degrees and the
966 HDD temperature drops to 41 degrees. These thresholds cannot
967 currently be controlled.
969 The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
970 certain conditions are met. It will override any fan programming done
971 through thinkpad-acpi.
973 The thinkpad-acpi kernel driver can be programmed to revert the fan
974 level to a safe setting if userspace does not issue one of the procfs
975 fan commands: "enable", "disable", "level" or "watchdog", or if there
976 are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
977 set to 1, manual mode) within a configurable amount of time of up to
978 120 seconds. This functionality is called fan safety watchdog.
980 Note that the watchdog timer stops after it enables the fan. It will be
981 rearmed again automatically (using the same interval) when one of the
982 above mentioned fan commands is received. The fan watchdog is,
983 therefore, not suitable to protect against fan mode changes made through
984 means other than the "enable", "disable", and "level" procfs fan
985 commands, or the hwmon fan control sysfs interface.
989 The fan may be enabled or disabled with the following commands:
991 echo enable >/proc/acpi/ibm/fan
992 echo disable >/proc/acpi/ibm/fan
994 Placing a fan on level 0 is the same as disabling it. Enabling a fan
995 will try to place it in a safe level if it is too slow or disabled.
997 The fan level can be controlled with the command:
999 echo 'level <level>' > /proc/acpi/ibm/fan
1001 Where <level> is an integer from 0 to 7, or one of the words "auto" or
1002 "full-speed" (without the quotes). Not all ThinkPads support the "auto"
1003 and "full-speed" levels. The driver accepts "disengaged" as an alias for
1004 "full-speed", and reports it as "disengaged" for backwards
1007 On the X31 and X40 (and ONLY on those models), the fan speed can be
1008 controlled to a certain degree. Once the fan is running, it can be
1009 forced to run faster or slower with the following command:
1011 echo 'speed <speed>' > /proc/acpi/ibm/fan
1013 The sustainable range of fan speeds on the X40 appears to be from about
1014 3700 to about 7350. Values outside this range either do not have any
1015 effect or the fan speed eventually settles somewhere in that range. The
1016 fan cannot be stopped or started with this command. This functionality
1017 is incomplete, and not available through the sysfs interface.
1019 To program the safety watchdog, use the "watchdog" command.
1021 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
1023 If you want to disable the watchdog, use 0 as the interval.
1027 The sysfs interface follows the hwmon subsystem guidelines for the most
1028 part, and the exception is the fan safety watchdog.
1030 Writes to any of the sysfs attributes may return the EINVAL error if
1031 that operation is not supported in a given ThinkPad or if the parameter
1032 is out-of-bounds, and EPERM if it is forbidden. They may also return
1033 EINTR (interrupted system call), and EIO (I/O error while trying to talk
1036 Features not yet implemented by the driver return ENOSYS.
1038 hwmon device attribute pwm1_enable:
1039 0: PWM offline (fan is set to full-speed mode)
1040 1: Manual PWM control (use pwm1 to set fan level)
1041 2: Hardware PWM control (EC "auto" mode)
1042 3: reserved (Software PWM control, not implemented yet)
1044 Modes 0 and 2 are not supported by all ThinkPads, and the
1045 driver is not always able to detect this. If it does know a
1046 mode is unsupported, it will return -EINVAL.
1048 hwmon device attribute pwm1:
1049 Fan level, scaled from the firmware values of 0-7 to the hwmon
1050 scale of 0-255. 0 means fan stopped, 255 means highest normal
1053 This attribute only commands the fan if pmw1_enable is set to 1
1054 (manual PWM control).
1056 hwmon device attribute fan1_input:
1057 Fan tachometer reading, in RPM. May go stale on certain
1058 ThinkPads while the EC transitions the PWM to offline mode,
1059 which can take up to two minutes. May return rubbish on older
1062 driver attribute fan_watchdog:
1063 Fan safety watchdog timer interval, in seconds. Minimum is
1064 1 second, maximum is 120 seconds. 0 disables the watchdog.
1066 To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
1068 To start the fan in a safe mode: set pwm1_enable to 2. If that fails
1069 with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
1070 would be the safest choice, though).
1076 procfs: /proc/acpi/ibm/wan
1077 sysfs device attribute: wwan_enable
1079 This feature is marked EXPERIMENTAL because the implementation
1080 directly accesses hardware registers and may not work as expected. USE
1081 WITH CAUTION! To use this feature, you need to supply the
1082 experimental=1 parameter when loading the module.
1084 This feature shows the presence and current state of a W-WAN (Sierra
1085 Wireless EV-DO) device.
1087 It was tested on a Lenovo Thinkpad X60. It should probably work on other
1088 Thinkpad models which come with this module installed.
1092 If the W-WAN card is installed, the following commands can be used:
1094 echo enable > /proc/acpi/ibm/wan
1095 echo disable > /proc/acpi/ibm/wan
1099 If the W-WAN card is installed, it can be enabled /
1100 disabled through the "wwan_enable" thinkpad-acpi device
1101 attribute, and its current status can also be queried.
1104 0: disables WWAN card / WWAN card is disabled
1105 1: enables WWAN card / WWAN card is enabled.
1107 Note: this interface will be probably be superseeded by the
1108 generic rfkill class, so it is NOT to be considered stable yet.
1110 Multiple Commands, Module Parameters
1111 ------------------------------------
1113 Multiple commands can be written to the proc files in one shot by
1114 separating them with commas, for example:
1116 echo enable,0xffff > /proc/acpi/ibm/hotkey
1117 echo lcd_disable,crt_enable > /proc/acpi/ibm/video
1119 Commands can also be specified when loading the thinkpad-acpi module,
1122 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
1124 Enabling debugging output
1125 -------------------------
1127 The module takes a debug paramater which can be used to selectively
1128 enable various classes of debugging output, for example:
1130 modprobe ibm_acpi debug=0xffff
1132 will enable all debugging output classes. It takes a bitmask, so
1133 to enable more than one output class, just add their values.
1135 Debug bitmask Description
1136 0x0001 Initialization and probing
1139 There is also a kernel build option to enable more debugging
1140 information, which may be necessary to debug driver problems.
1142 The level of debugging information output by the driver can be changed
1143 at runtime through sysfs, using the driver attribute debug_level. The
1144 attribute takes the same bitmask as the debug module parameter above.
1146 Force loading of module
1147 -----------------------
1149 If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
1150 the module parameter force_load=1. Regardless of whether this works or
1151 not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
1154 Sysfs interface changelog:
1156 0x000100: Initial sysfs support, as a single platform driver and
1158 0x000200: Hot key support for 32 hot keys, and radio slider switch
1160 0x010000: Hot keys are now handled by default over the input
1161 layer, the radio switch generates input event EV_RADIO,
1162 and the driver enables hot key handling by default in