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. It was moved to drivers/platform/x86 for
20 kernel 2.6.29 and release 0.22.
22 The driver is named "thinkpad-acpi". In some places, like module
23 names and log messages, "thinkpad_acpi" is used because of userspace
26 "tpacpi" is used as a shorthand where "thinkpad-acpi" would be too
27 long due to length limitations on some Linux kernel versions.
32 The features currently supported are the following (see below for
33 detailed description):
36 - Bluetooth enable and disable
37 - video output switching, expansion control
38 - ThinkLight on and off
39 - limited docking and undocking
45 - Experimental: embedded controller register dump
46 - LCD brightness control
48 - Fan control and monitoring: fan speed, fan enable/disable
49 - WAN enable and disable
50 - UWB enable and disable
52 A compatibility table by model and feature is maintained on the web
53 site, http://ibm-acpi.sf.net/. I appreciate any success or failure
54 reports, especially if they add to or correct the compatibility table.
55 Please include the following information in your report:
58 - a copy of your ACPI tables, using the "acpidump" utility
59 - a copy of the output of dmidecode, with serial numbers
61 - which driver features work and which don't
62 - the observed behavior of non-working features
64 Any other comments or patches are also more than welcome.
70 If you are compiling this driver as included in the Linux kernel
71 sources, look for the CONFIG_THINKPAD_ACPI Kconfig option.
72 It is located on the menu path: "Device Drivers" -> "X86 Platform
73 Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras".
79 The driver exports two different interfaces to userspace, which can be
80 used to access the features it provides. One is a legacy procfs-based
81 interface, which will be removed at some time in the future. The other
82 is a new sysfs-based interface which is not complete yet.
84 The procfs interface creates the /proc/acpi/ibm directory. There is a
85 file under that directory for each feature it supports. The procfs
86 interface is mostly frozen, and will change very little if at all: it
87 will not be extended to add any new functionality in the driver, instead
88 all new functionality will be implemented on the sysfs interface.
90 The sysfs interface tries to blend in the generic Linux sysfs subsystems
91 and classes as much as possible. Since some of these subsystems are not
92 yet ready or stabilized, it is expected that this interface will change,
93 and any and all userspace programs must deal with it.
96 Notes about the sysfs interface:
98 Unlike what was done with the procfs interface, correctness when talking
99 to the sysfs interfaces will be enforced, as will correctness in the
100 thinkpad-acpi's implementation of sysfs interfaces.
102 Also, any bugs in the thinkpad-acpi sysfs driver code or in the
103 thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
104 maximum correctness, even if that means changing an interface in
105 non-compatible ways. As these interfaces mature both in the kernel and
106 in thinkpad-acpi, such changes should become quite rare.
108 Applications interfacing to the thinkpad-acpi sysfs interfaces must
109 follow all sysfs guidelines and correctly process all errors (the sysfs
110 interface makes extensive use of errors). File descriptors and open /
111 close operations to the sysfs inodes must also be properly implemented.
113 The version of thinkpad-acpi's sysfs interface is exported by the driver
114 as a driver attribute (see below).
116 Sysfs driver attributes are on the driver's sysfs attribute space,
117 for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and
118 /sys/bus/platform/drivers/thinkpad_hwmon/
120 Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
121 space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/.
123 Sysfs device attributes for the sensors and fan are on the
124 thinkpad_hwmon device's sysfs attribute space, but you should locate it
125 looking for a hwmon device with the name attribute of "thinkpad", or
126 better yet, through libsensors.
132 procfs: /proc/acpi/ibm/driver
133 sysfs driver attribute: version
135 The driver name and version. No commands can be written to this file.
138 Sysfs interface version
139 -----------------------
141 sysfs driver attribute: interface_version
143 Version of the thinkpad-acpi sysfs interface, as an unsigned long
144 (output in hex format: 0xAAAABBCC), where:
145 AAAA - major revision
149 The sysfs interface version changelog for the driver can be found at the
150 end of this document. Changes to the sysfs interface done by the kernel
151 subsystems are not documented here, nor are they tracked by this
154 Changes to the thinkpad-acpi sysfs interface are only considered
155 non-experimental when they are submitted to Linux mainline, at which
156 point the changes in this interface are documented and interface_version
157 may be updated. If you are using any thinkpad-acpi features not yet
158 sent to mainline for merging, you do so on your own risk: these features
159 may disappear, or be implemented in a different and incompatible way by
160 the time they are merged in Linux mainline.
162 Changes that are backwards-compatible by nature (e.g. the addition of
163 attributes that do not change the way the other attributes work) do not
164 always warrant an update of interface_version. Therefore, one must
165 expect that an attribute might not be there, and deal with it properly
166 (an attribute not being there *is* a valid way to make it clear that a
167 feature is not available in sysfs).
173 procfs: /proc/acpi/ibm/hotkey
174 sysfs device attribute: hotkey_*
176 In a ThinkPad, the ACPI HKEY handler is responsible for communicating
177 some important events and also keyboard hot key presses to the operating
178 system. Enabling the hotkey functionality of thinkpad-acpi signals the
179 firmware that such a driver is present, and modifies how the ThinkPad
180 firmware will behave in many situations.
182 The driver enables the hot key feature automatically when loaded. The
183 feature can later be disabled and enabled back at runtime. The driver
184 will also restore the hot key feature to its previous state and mask
187 When the hotkey feature is enabled and the hot key mask is set (see
188 below), the driver will report HKEY events in the following format:
190 ibm/hotkey HKEY 00000080 0000xxxx
192 Some of these events refer to hot key presses, but not all.
194 The driver will generate events over the input layer for hot keys and
195 radio switches, and over the ACPI netlink layer for other events. The
196 input layer support accepts the standard IOCTLs to remap the keycodes
197 assigned to each hot key.
199 The hot key bit mask allows some control over which hot keys generate
200 events. If a key is "masked" (bit set to 0 in the mask), the firmware
201 will handle it. If it is "unmasked", it signals the firmware that
202 thinkpad-acpi would prefer to handle it, if the firmware would be so
203 kind to allow it (and it often doesn't!).
205 Not all bits in the mask can be modified. Not all bits that can be
206 modified do anything. Not all hot keys can be individually controlled
207 by the mask. Some models do not support the mask at all, and in those
208 models, hot keys cannot be controlled individually. The behaviour of
209 the mask is, therefore, highly dependent on the ThinkPad model.
211 Note that unmasking some keys prevents their default behavior. For
212 example, if Fn+F5 is unmasked, that key will no longer enable/disable
215 Note also that not all Fn key combinations are supported through ACPI.
216 For example, on the X40, the brightness, volume and "Access IBM" buttons
217 do not generate ACPI events even with this driver. They *can* be used
218 through the "ThinkPad Buttons" utility, see http://www.nongnu.org/tpb/
222 The following commands can be written to the /proc/acpi/ibm/hotkey file:
224 echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature
225 echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature
226 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
227 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
228 ... any other 8-hex-digit mask ...
229 echo reset > /proc/acpi/ibm/hotkey -- restore the original mask
231 The procfs interface does not support NVRAM polling control. So as to
232 maintain maximum bug-to-bug compatibility, it does not report any masks,
233 nor does it allow one to manipulate the hot key mask when the firmware
234 does not support masks at all, even if NVRAM polling is in use.
239 Returns the status of the hot keys feature when
240 thinkpad-acpi was loaded. Upon module unload, the hot
241 key feature status will be restored to this value.
243 0: hot keys were disabled
244 1: hot keys were enabled (unusual)
247 Returns the hot keys mask when thinkpad-acpi was loaded.
248 Upon module unload, the hot keys mask will be restored
252 Enables/disables the hot keys feature in the ACPI
253 firmware, and reports current status of the hot keys
254 feature. Has no effect on the NVRAM hot key polling
257 0: disables the hot keys feature / feature disabled
258 1: enables the hot keys feature / feature enabled
261 bit mask to enable driver-handling (and depending on
262 the firmware, ACPI event generation) for each hot key
263 (see above). Returns the current status of the hot keys
264 mask, and allows one to modify it.
266 Note: when NVRAM polling is active, the firmware mask
267 will be different from the value returned by
268 hotkey_mask. The driver will retain enabled bits for
269 hotkeys that are under NVRAM polling even if the
270 firmware refuses them, and will not set these bits on
271 the firmware hot key mask.
274 bit mask that should enable event reporting for all
275 supported hot keys, when echoed to hotkey_mask above.
276 Unless you know which events need to be handled
277 passively (because the firmware *will* handle them
278 anyway), do *not* use hotkey_all_mask. Use
279 hotkey_recommended_mask, instead. You have been warned.
281 hotkey_recommended_mask:
282 bit mask that should enable event reporting for all
283 supported hot keys, except those which are always
284 handled by the firmware anyway. Echo it to
285 hotkey_mask above, to use.
288 bit mask that selects which hot keys will the driver
289 poll the NVRAM for. This is auto-detected by the driver
290 based on the capabilities reported by the ACPI firmware,
291 but it can be overridden at runtime.
293 Hot keys whose bits are set in both hotkey_source_mask
294 and also on hotkey_mask are polled for in NVRAM. Only a
295 few hot keys are available through CMOS NVRAM polling.
297 Warning: when in NVRAM mode, the volume up/down/mute
298 keys are synthesized according to changes in the mixer,
299 so you have to use volume up or volume down to unmute,
300 as per the ThinkPad volume mixer user interface. When
301 in ACPI event mode, volume up/down/mute are reported as
302 separate events, but this behaviour may be corrected in
303 future releases of this driver, in which case the
304 ThinkPad volume mixer user interface semantics will be
308 frequency in Hz for hot key polling. It must be between
309 0 and 25 Hz. Polling is only carried out when strictly
312 Setting hotkey_poll_freq to zero disables polling, and
313 will cause hot key presses that require NVRAM polling
314 to never be reported.
316 Setting hotkey_poll_freq too low will cause repeated
317 pressings of the same hot key to be misreported as a
318 single key press, or to not even be detected at all.
319 The recommended polling frequency is 10Hz.
322 If the ThinkPad has a hardware radio switch, this
323 attribute will read 0 if the switch is in the "radios
324 disabled" position, and 1 if the switch is in the
325 "radios enabled" position.
327 This attribute has poll()/select() support.
330 If the ThinkPad has tablet capabilities, this attribute
331 will read 0 if the ThinkPad is in normal mode, and
332 1 if the ThinkPad is in tablet mode.
334 This attribute has poll()/select() support.
337 Returns the state of the procfs ACPI event report mode
338 filter for hot keys. If it is set to 1 (the default),
339 all hot key presses are reported both through the input
340 layer and also as ACPI events through procfs (but not
341 through netlink). If it is set to 2, hot key presses
342 are reported only through the input layer.
344 This attribute is read-only in kernels 2.6.23 or later,
345 and read-write on earlier kernels.
347 May return -EPERM (write access locked out by module
348 parameter) or -EACCES (read-only).
351 Set to 1 if the system is waking up because the user
352 requested a bay ejection. Set to 2 if the system is
353 waking up because the user requested the system to
354 undock. Set to zero for normal wake-ups or wake-ups
355 due to unknown reasons.
357 This attribute has poll()/select() support.
359 wakeup_hotunplug_complete:
360 Set to 1 if the system was waken up because of an
361 undock or bay ejection request, and that request
362 was successfully completed. At this point, it might
363 be useful to send the system back to sleep, at the
364 user's choice. Refer to HKEY events 0x4003 and
367 This attribute has poll()/select() support.
371 A Hot key is mapped to a single input layer EV_KEY event, possibly
372 followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
373 code. An EV_SYN event will always be generated to mark the end of the
376 Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
377 used as a helper to remap keys, only. They are particularly useful when
378 remapping KEY_UNKNOWN keys.
380 The events are available in an input device, with the following id:
383 vendor: 0x1014 (PCI_VENDOR_ID_IBM) or
384 0x17aa (PCI_VENDOR_ID_LENOVO)
385 product: 0x5054 ("TP")
388 The version will have its LSB incremented if the keymap changes in a
389 backwards-compatible way. The MSB shall always be 0x41 for this input
390 device. If the MSB is not 0x41, do not use the device as described in
391 this section, as it is either something else (e.g. another input device
392 exported by a thinkpad driver, such as HDAPS) or its functionality has
393 been changed in a non-backwards compatible way.
395 Adding other event types for other functionalities shall be considered a
396 backwards-compatible change for this input device.
398 Thinkpad-acpi Hot Key event map (version 0x4101):
404 0x1002 0x01 FN+F2 IBM: battery (rare)
407 0x1003 0x02 FN+F3 Many IBM models always report
408 this hot key, even with hot keys
409 disabled or with Fn+F3 masked
414 0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
415 semantics, i.e. sleep-to-RAM).
416 It is always generate some kind
417 of event, either the hot key
418 event or a ACPI sleep button
419 event. The firmware may
420 refuse to generate further FN+F4
421 key presses until a S3 or S4 ACPI
422 sleep cycle is performed or some
425 0x1005 0x04 FN+F5 Radio. Enables/disables
426 the internal Bluetooth hardware
427 and W-WAN card if left in control
428 of the firmware. Does not affect
430 Should be used to turn on/off all
431 radios (Bluetooth+W-WAN+WLAN),
436 0x1007 0x06 FN+F7 Video output cycle.
437 Do you feel lucky today?
439 0x1008 0x07 FN+F8 IBM: toggle screen expand
440 Lenovo: configure UltraNav
446 0x100C 0x0B FN+F12 Sleep to disk. You are always
447 supposed to handle it yourself,
448 either through the ACPI event,
449 or through a hotkey event.
450 The firmware may refuse to
451 generate further FN+F4 key
452 press events until a S3 or S4
453 ACPI sleep cycle is performed,
456 0x100D 0x0C FN+BACKSPACE -
457 0x100E 0x0D FN+INSERT -
458 0x100F 0x0E FN+DELETE -
460 0x1010 0x0F FN+HOME Brightness up. This key is
461 always handled by the firmware
462 in IBM ThinkPads, even when
463 unmasked. Just leave it alone.
464 For Lenovo ThinkPads with a new
465 BIOS, it has to be handled either
466 by the ACPI OSI, or by userspace.
467 0x1011 0x10 FN+END Brightness down. See brightness
470 0x1012 0x11 FN+PGUP ThinkLight toggle. This key is
471 always handled by the firmware,
474 0x1013 0x12 FN+PGDOWN -
476 0x1014 0x13 FN+SPACE Zoom key
478 0x1015 0x14 VOLUME UP Internal mixer volume up. This
479 key is always handled by the
480 firmware, even when unmasked.
481 NOTE: Lenovo seems to be changing
483 0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
484 key is always handled by the
485 firmware, even when unmasked.
486 NOTE: Lenovo seems to be changing
488 0x1017 0x16 MUTE Mute internal mixer. This
489 key is always handled by the
490 firmware, even when unmasked.
492 0x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key
498 The ThinkPad firmware does not allow one to differentiate when most hot
499 keys are pressed or released (either that, or we don't know how to, yet).
500 For these keys, the driver generates a set of events for a key press and
501 immediately issues the same set of events for a key release. It is
502 unknown by the driver if the ThinkPad firmware triggered these events on
503 hot key press or release, but the firmware will do it for either one, not
506 If a key is mapped to KEY_RESERVED, it generates no input events at all.
507 If a key is mapped to KEY_UNKNOWN, it generates an input event that
508 includes an scan code. If a key is mapped to anything else, it will
509 generate input device EV_KEY events.
511 In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
514 SW_RFKILL_ALL T60 and later hardare rfkill rocker switch
515 SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
517 Non hot-key ACPI HKEY event map:
520 0x5009 Tablet swivel: switched to tablet mode
521 0x500A Tablet swivel: switched to normal mode
522 0x7000 Radio Switch may have changed state
524 The above events are not propagated by the driver, except for legacy
525 compatibility purposes when hotkey_report_mode is set to 1.
527 0x2304 System is waking up from suspend to undock
528 0x2305 System is waking up from suspend to eject bay
529 0x2404 System is waking up from hibernation to undock
530 0x2405 System is waking up from hibernation to eject bay
532 The above events are never propagated by the driver.
534 0x3003 Bay ejection (see 0x2x05) complete, can sleep again
535 0x4003 Undocked (see 0x2x04), can sleep again
536 0x500B Tablet pen inserted into its storage bay
537 0x500C Tablet pen removed from its storage bay
538 0x5010 Brightness level changed (newer Lenovo BIOSes)
540 The above events are propagated by the driver.
544 ibm-acpi and thinkpad-acpi 0.15 (mainline kernels before 2.6.23) never
545 supported the input layer, and sent events over the procfs ACPI event
548 To avoid sending duplicate events over the input layer and the ACPI
549 event interface, thinkpad-acpi 0.16 implements a module parameter
550 (hotkey_report_mode), and also a sysfs device attribute with the same
553 Make no mistake here: userspace is expected to switch to using the input
554 layer interface of thinkpad-acpi, together with the ACPI netlink event
555 interface in kernels 2.6.23 and later, or with the ACPI procfs event
556 interface in kernels 2.6.22 and earlier.
558 If no hotkey_report_mode module parameter is specified (or it is set to
559 zero), the driver defaults to mode 1 (see below), and on kernels 2.6.22
560 and earlier, also allows one to change the hotkey_report_mode through
561 sysfs. In kernels 2.6.23 and later, where the netlink ACPI event
562 interface is available, hotkey_report_mode cannot be changed through
563 sysfs (it is read-only).
565 If the hotkey_report_mode module parameter is set to 1 or 2, it cannot
566 be changed later through sysfs (any writes will return -EPERM to signal
567 that hotkey_report_mode was locked. On 2.6.23 and later, where
568 hotkey_report_mode cannot be changed at all, writes will return -EACCES).
570 hotkey_report_mode set to 1 makes the driver export through the procfs
571 ACPI event interface all hot key presses (which are *also* sent to the
572 input layer). This is a legacy compatibility behaviour, and it is also
573 the default mode of operation for the driver.
575 hotkey_report_mode set to 2 makes the driver filter out the hot key
576 presses from the procfs ACPI event interface, so these events will only
577 be sent through the input layer. Userspace that has been updated to use
578 the thinkpad-acpi input layer interface should set hotkey_report_mode to
581 Hot key press events are never sent to the ACPI netlink event interface.
582 Really up-to-date userspace under kernel 2.6.23 and later is to use the
583 netlink interface and the input layer interface, and don't bother at all
584 with hotkey_report_mode.
587 Brightness hotkey notes:
589 These are the current sane choices for brightness key mapping in
592 For IBM and Lenovo models *without* ACPI backlight control (the ones on
593 which thinkpad-acpi will autoload its backlight interface by default,
594 and on which ACPI video does not export a backlight interface):
596 1. Don't enable or map the brightness hotkeys in thinkpad-acpi, as
597 these older firmware versions unfortunately won't respect the hotkey
598 mask for brightness keys anyway, and always reacts to them. This
599 usually work fine, unless X.org drivers are doing something to block
600 the BIOS. In that case, use (3) below. This is the default mode of
603 2. Enable the hotkeys, but map them to something else that is NOT
604 KEY_BRIGHTNESS_UP/DOWN or any other keycode that would cause
605 userspace to try to change the backlight level, and use that as an
606 on-screen-display hint.
608 3. IF AND ONLY IF X.org drivers find a way to block the firmware from
609 automatically changing the brightness, enable the hotkeys and map
610 them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN, and feed that to
611 something that calls xbacklight. thinkpad-acpi will not be able to
612 change brightness in that case either, so you should disable its
615 For Lenovo models *with* ACPI backlight control:
617 1. Load up ACPI video and use that. ACPI video will report ACPI
618 events for brightness change keys. Do not mess with thinkpad-acpi
619 defaults in this case. thinkpad-acpi should not have anything to do
620 with backlight events in a scenario where ACPI video is loaded:
621 brightness hotkeys must be disabled, and the backlight interface is
622 to be kept disabled as well. This is the default mode of operation.
624 2. Do *NOT* load up ACPI video, enable the hotkeys in thinkpad-acpi,
625 and map them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN. Process
626 these keys on userspace somehow (e.g. by calling xbacklight).
632 procfs: /proc/acpi/ibm/bluetooth
633 sysfs device attribute: bluetooth_enable (deprecated)
634 sysfs rfkill class: switch "tpacpi_bluetooth_sw"
636 This feature shows the presence and current state of a ThinkPad
637 Bluetooth device in the internal ThinkPad CDC slot.
639 If the ThinkPad supports it, the Bluetooth state is stored in NVRAM,
640 so it is kept across reboots and power-off.
644 If Bluetooth is installed, the following commands can be used:
646 echo enable > /proc/acpi/ibm/bluetooth
647 echo disable > /proc/acpi/ibm/bluetooth
651 If the Bluetooth CDC card is installed, it can be enabled /
652 disabled through the "bluetooth_enable" thinkpad-acpi device
653 attribute, and its current status can also be queried.
656 0: disables Bluetooth / Bluetooth is disabled
657 1: enables Bluetooth / Bluetooth is enabled.
659 Note: this interface has been superseded by the generic rfkill
660 class. It has been deprecated, and it will be removed in year
663 rfkill controller switch "tpacpi_bluetooth_sw": refer to
664 Documentation/rfkill.txt for details.
667 Video output control -- /proc/acpi/ibm/video
668 --------------------------------------------
670 This feature allows control over the devices used for video output -
671 LCD, CRT or DVI (if available). The following commands are available:
673 echo lcd_enable > /proc/acpi/ibm/video
674 echo lcd_disable > /proc/acpi/ibm/video
675 echo crt_enable > /proc/acpi/ibm/video
676 echo crt_disable > /proc/acpi/ibm/video
677 echo dvi_enable > /proc/acpi/ibm/video
678 echo dvi_disable > /proc/acpi/ibm/video
679 echo auto_enable > /proc/acpi/ibm/video
680 echo auto_disable > /proc/acpi/ibm/video
681 echo expand_toggle > /proc/acpi/ibm/video
682 echo video_switch > /proc/acpi/ibm/video
684 Each video output device can be enabled or disabled individually.
685 Reading /proc/acpi/ibm/video shows the status of each device.
687 Automatic video switching can be enabled or disabled. When automatic
688 video switching is enabled, certain events (e.g. opening the lid,
689 docking or undocking) cause the video output device to change
690 automatically. While this can be useful, it also causes flickering
691 and, on the X40, video corruption. By disabling automatic switching,
692 the flickering or video corruption can be avoided.
694 The video_switch command cycles through the available video outputs
695 (it simulates the behavior of Fn-F7).
697 Video expansion can be toggled through this feature. This controls
698 whether the display is expanded to fill the entire LCD screen when a
699 mode with less than full resolution is used. Note that the current
700 video expansion status cannot be determined through this feature.
702 Note that on many models (particularly those using Radeon graphics
703 chips) the X driver configures the video card in a way which prevents
704 Fn-F7 from working. This also disables the video output switching
705 features of this driver, as it uses the same ACPI methods as
706 Fn-F7. Video switching on the console should still work.
708 UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000
714 procfs: /proc/acpi/ibm/light
715 sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
719 The ThinkLight status can be read and set through the procfs interface. A
720 few models which do not make the status available will show the ThinkLight
721 status as "unknown". The available commands are:
723 echo on > /proc/acpi/ibm/light
724 echo off > /proc/acpi/ibm/light
728 The ThinkLight sysfs interface is documented by the LED class
729 documentation, in Documentation/leds-class.txt. The ThinkLight LED name
730 is "tpacpi::thinklight".
732 Due to limitations in the sysfs LED class, if the status of the ThinkLight
733 cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
734 It is impossible to know if the status returned through sysfs is valid.
737 Docking / undocking -- /proc/acpi/ibm/dock
738 ------------------------------------------
740 Docking and undocking (e.g. with the X4 UltraBase) requires some
741 actions to be taken by the operating system to safely make or break
742 the electrical connections with the dock.
744 The docking feature of this driver generates the following ACPI events:
746 ibm/dock GDCK 00000003 00000001 -- eject request
747 ibm/dock GDCK 00000003 00000002 -- undocked
748 ibm/dock GDCK 00000000 00000003 -- docked
750 NOTE: These events will only be generated if the laptop was docked
751 when originally booted. This is due to the current lack of support for
752 hot plugging of devices in the Linux ACPI framework. If the laptop was
753 booted while not in the dock, the following message is shown in the
756 Mar 17 01:42:34 aero kernel: thinkpad_acpi: dock device not present
758 In this case, no dock-related events are generated but the dock and
759 undock commands described below still work. They can be executed
760 manually or triggered by Fn key combinations (see the example acpid
761 configuration files included in the driver tarball package available
764 When the eject request button on the dock is pressed, the first event
765 above is generated. The handler for this event should issue the
768 echo undock > /proc/acpi/ibm/dock
770 After the LED on the dock goes off, it is safe to eject the laptop.
771 Note: if you pressed this key by mistake, go ahead and eject the
772 laptop, then dock it back in. Otherwise, the dock may not function as
775 When the laptop is docked, the third event above is generated. The
776 handler for this event should issue the following command to fully
779 echo dock > /proc/acpi/ibm/dock
781 The contents of the /proc/acpi/ibm/dock file shows the current status
782 of the dock, as provided by the ACPI framework.
784 The docking support in this driver does not take care of enabling or
785 disabling any other devices you may have attached to the dock. For
786 example, a CD drive plugged into the UltraBase needs to be disabled or
787 enabled separately. See the provided example acpid configuration files
788 for how this can be accomplished.
790 There is no support yet for PCI devices that may be attached to a
791 docking station, e.g. in the ThinkPad Dock II. The driver currently
792 does not recognize, enable or disable such devices. This means that
793 the only docking stations currently supported are the X-series
794 UltraBase docks and "dumb" port replicators like the Mini Dock (the
795 latter don't need any ACPI support, actually).
798 UltraBay eject -- /proc/acpi/ibm/bay
799 ------------------------------------
801 Inserting or ejecting an UltraBay device requires some actions to be
802 taken by the operating system to safely make or break the electrical
803 connections with the device.
805 This feature generates the following ACPI events:
807 ibm/bay MSTR 00000003 00000000 -- eject request
808 ibm/bay MSTR 00000001 00000000 -- eject lever inserted
810 NOTE: These events will only be generated if the UltraBay was present
811 when the laptop was originally booted (on the X series, the UltraBay
812 is in the dock, so it may not be present if the laptop was undocked).
813 This is due to the current lack of support for hot plugging of devices
814 in the Linux ACPI framework. If the laptop was booted without the
815 UltraBay, the following message is shown in the logs:
817 Mar 17 01:42:34 aero kernel: thinkpad_acpi: bay device not present
819 In this case, no bay-related events are generated but the eject
820 command described below still works. It can be executed manually or
821 triggered by a hot key combination.
823 Sliding the eject lever generates the first event shown above. The
824 handler for this event should take whatever actions are necessary to
825 shut down the device in the UltraBay (e.g. call idectl), then issue
826 the following command:
828 echo eject > /proc/acpi/ibm/bay
830 After the LED on the UltraBay goes off, it is safe to pull out the
833 When the eject lever is inserted, the second event above is
834 generated. The handler for this event should take whatever actions are
835 necessary to enable the UltraBay device (e.g. call idectl).
837 The contents of the /proc/acpi/ibm/bay file shows the current status
838 of the UltraBay, as provided by the ACPI framework.
840 EXPERIMENTAL warm eject support on the 600e/x, A22p and A3x (To use
841 this feature, you need to supply the experimental=1 parameter when
844 These models do not have a button near the UltraBay device to request
845 a hot eject but rather require the laptop to be put to sleep
846 (suspend-to-ram) before the bay device is ejected or inserted).
847 The sequence of steps to eject the device is as follows:
849 echo eject > /proc/acpi/ibm/bay
850 put the ThinkPad to sleep
853 cat /proc/acpi/ibm/bay should show that the drive was removed
855 On the A3x, both the UltraBay 2000 and UltraBay Plus devices are
856 supported. Use "eject2" instead of "eject" for the second bay.
858 Note: the UltraBay eject support on the 600e/x, A22p and A3x is
859 EXPERIMENTAL and may not work as expected. USE WITH CAUTION!
865 procfs: /proc/acpi/ibm/cmos
866 sysfs device attribute: cmos_command
868 This feature is mostly used internally by the ACPI firmware to keep the legacy
869 CMOS NVRAM bits in sync with the current machine state, and to record this
870 state so that the ThinkPad will retain such settings across reboots.
872 Some of these commands actually perform actions in some ThinkPad models, but
873 this is expected to disappear more and more in newer models. As an example, in
874 a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
875 real, but commands 0 to 2 don't control the mixer anymore (they have been
876 phased out) and just update the NVRAM.
878 The range of valid cmos command numbers is 0 to 21, but not all have an
879 effect and the behavior varies from model to model. Here is the behavior
880 on the X40 (tpb is the ThinkPad Buttons utility):
882 0 - Related to "Volume down" key press
883 1 - Related to "Volume up" key press
884 2 - Related to "Mute on" key press
885 3 - Related to "Access IBM" key press
886 4 - Related to "LCD brightness up" key press
887 5 - Related to "LCD brightness down" key press
888 11 - Related to "toggle screen expansion" key press/function
889 12 - Related to "ThinkLight on"
890 13 - Related to "ThinkLight off"
891 14 - Related to "ThinkLight" key press (toggle ThinkLight)
893 The cmos command interface is prone to firmware split-brain problems, as
894 in newer ThinkPads it is just a compatibility layer. Do not use it, it is
895 exported just as a debug tool.
901 procfs: /proc/acpi/ibm/led
902 sysfs attributes: as per LED class, see below for names
904 Some of the LED indicators can be controlled through this feature. On
905 some older ThinkPad models, it is possible to query the status of the
906 LED indicators as well. Newer ThinkPads cannot query the real status
907 of the LED indicators.
911 The available commands are:
913 echo '<LED number> on' >/proc/acpi/ibm/led
914 echo '<LED number> off' >/proc/acpi/ibm/led
915 echo '<LED number> blink' >/proc/acpi/ibm/led
917 The <LED number> range is 0 to 7. The set of LEDs that can be
918 controlled varies from model to model. Here is the common ThinkPad
926 5 - UltraBase battery slot
930 All of the above can be turned on and off and can be made to blink.
934 The ThinkPad LED sysfs interface is described in detail by the LED class
935 documentation, in Documentation/leds-class.txt.
937 The leds are named (in LED ID order, from 0 to 7):
938 "tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
939 "tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
940 "tpacpi::unknown_led", "tpacpi::standby".
942 Due to limitations in the sysfs LED class, if the status of the LED
943 indicators cannot be read due to an error, thinkpad-acpi will report it as
944 a brightness of zero (same as LED off).
946 If the thinkpad firmware doesn't support reading the current status,
947 trying to read the current LED brightness will just return whatever
948 brightness was last written to that attribute.
950 These LEDs can blink using hardware acceleration. To request that a
951 ThinkPad indicator LED should blink in hardware accelerated mode, use the
952 "timer" trigger, and leave the delay_on and delay_off parameters set to
953 zero (to request hardware acceleration autodetection).
956 ACPI sounds -- /proc/acpi/ibm/beep
957 ----------------------------------
959 The BEEP method is used internally by the ACPI firmware to provide
960 audible alerts in various situations. This feature allows the same
961 sounds to be triggered manually.
963 The commands are non-negative integer numbers:
965 echo <number> >/proc/acpi/ibm/beep
967 The valid <number> range is 0 to 17. Not all numbers trigger sounds
968 and the sounds vary from model to model. Here is the behavior on the
971 0 - stop a sound in progress (but use 17 to stop 16)
972 2 - two beeps, pause, third beep ("low battery")
974 4 - high, followed by low-pitched beep ("unable")
976 6 - very high, followed by high-pitched beep ("AC/DC")
977 7 - high-pitched beep
978 9 - three short beeps
980 12 - low-pitched beep
981 15 - three high-pitched beeps repeating constantly, stop with 0
982 16 - one medium-pitched beep repeating constantly, stop with 17
989 procfs: /proc/acpi/ibm/thermal
990 sysfs device attributes: (hwmon "thinkpad") temp*_input
992 Most ThinkPads include six or more separate temperature sensors but only
993 expose the CPU temperature through the standard ACPI methods. This
994 feature shows readings from up to eight different sensors on older
995 ThinkPads, and up to sixteen different sensors on newer ThinkPads.
997 For example, on the X40, a typical output may be:
998 temperatures: 42 42 45 41 36 -128 33 -128
1000 On the T43/p, a typical output may be:
1001 temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
1003 The mapping of thermal sensors to physical locations varies depending on
1004 system-board model (and thus, on ThinkPad model).
1006 http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
1007 tries to track down these locations for various models.
1009 Most (newer?) models seem to follow this pattern:
1012 2: (depends on model)
1013 3: (depends on model)
1015 5: Main battery: main sensor
1016 6: Bay battery: main sensor
1017 7: Main battery: secondary sensor
1018 8: Bay battery: secondary sensor
1019 9-15: (depends on model)
1021 For the R51 (source: Thomas Gruber):
1025 For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
1026 http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
1027 2: System board, left side (near PCMCIA slot), reported as HDAPS temp
1029 9: MCH (northbridge) to DRAM Bus
1030 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
1031 card, under touchpad
1032 11: Power regulator, underside of system board, below F2 key
1034 The A31 has a very atypical layout for the thermal sensors
1035 (source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
1037 2: Main Battery: main sensor
1039 4: Bay Battery: main sensor
1040 5: MCH (northbridge)
1042 7: Main Battery: secondary sensor
1043 8: Bay Battery: secondary sensor
1047 Readings from sensors that are not available return -128.
1048 No commands can be written to this file.
1051 Sensors that are not available return the ENXIO error. This
1052 status may change at runtime, as there are hotplug thermal
1053 sensors, like those inside the batteries and docks.
1055 thinkpad-acpi thermal sensors are reported through the hwmon
1056 subsystem, and follow all of the hwmon guidelines at
1057 Documentation/hwmon.
1060 EXPERIMENTAL: Embedded controller register dump -- /proc/acpi/ibm/ecdump
1061 ------------------------------------------------------------------------
1063 This feature is marked EXPERIMENTAL because the implementation
1064 directly accesses hardware registers and may not work as expected. USE
1065 WITH CAUTION! To use this feature, you need to supply the
1066 experimental=1 parameter when loading the module.
1068 This feature dumps the values of 256 embedded controller
1069 registers. Values which have changed since the last time the registers
1070 were dumped are marked with a star:
1072 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
1073 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
1074 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
1075 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
1076 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
1077 EC 0x30: 01 07 1a 00 30 04 00 00 *85 00 00 10 00 50 00 00
1078 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
1079 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 *bc *02 *bc
1080 EC 0x60: *02 *bc *02 00 00 00 00 00 00 00 00 00 00 00 00 00
1081 EC 0x70: 00 00 00 00 00 12 30 40 *24 *26 *2c *27 *20 80 *1f 80
1082 EC 0x80: 00 00 00 06 *37 *0e 03 00 00 00 0e 07 00 00 00 00
1083 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1084 EC 0xa0: *ff 09 ff 09 ff ff *64 00 *00 *00 *a2 41 *ff *ff *e0 00
1085 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1086 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1087 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1088 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
1089 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
1091 This feature can be used to determine the register holding the fan
1092 speed on some models. To do that, do the following:
1094 - make sure the battery is fully charged
1095 - make sure the fan is running
1096 - run 'cat /proc/acpi/ibm/ecdump' several times, once per second or so
1098 The first step makes sure various charging-related values don't
1099 vary. The second ensures that the fan-related values do vary, since
1100 the fan speed fluctuates a bit. The third will (hopefully) mark the
1101 fan register with a star:
1103 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
1104 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
1105 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
1106 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
1107 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
1108 EC 0x30: 01 07 1a 00 30 04 00 00 85 00 00 10 00 50 00 00
1109 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
1110 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 bc 02 bc
1111 EC 0x60: 02 bc 02 00 00 00 00 00 00 00 00 00 00 00 00 00
1112 EC 0x70: 00 00 00 00 00 12 30 40 24 27 2c 27 21 80 1f 80
1113 EC 0x80: 00 00 00 06 *be 0d 03 00 00 00 0e 07 00 00 00 00
1114 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1115 EC 0xa0: ff 09 ff 09 ff ff 64 00 00 00 a2 41 ff ff e0 00
1116 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1117 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1118 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1119 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
1120 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
1122 Another set of values that varies often is the temperature
1123 readings. Since temperatures don't change vary fast, you can take
1124 several quick dumps to eliminate them.
1126 You can use a similar method to figure out the meaning of other
1127 embedded controller registers - e.g. make sure nothing else changes
1128 except the charging or discharging battery to determine which
1129 registers contain the current battery capacity, etc. If you experiment
1130 with this, do send me your results (including some complete dumps with
1131 a description of the conditions when they were taken.)
1134 LCD brightness control
1135 ----------------------
1137 procfs: /proc/acpi/ibm/brightness
1138 sysfs backlight device "thinkpad_screen"
1140 This feature allows software control of the LCD brightness on ThinkPad
1141 models which don't have a hardware brightness slider.
1143 It has some limitations: the LCD backlight cannot be actually turned
1144 on or off by this interface, it just controls the backlight brightness
1147 On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
1148 has eight brightness levels, ranging from 0 to 7. Some of the levels
1149 may not be distinct. Later Lenovo models that implement the ACPI
1150 display backlight brightness control methods have 16 levels, ranging
1153 There are two interfaces to the firmware for direct brightness control,
1154 EC and CMOS. To select which one should be used, use the
1155 brightness_mode module parameter: brightness_mode=1 selects EC mode,
1156 brightness_mode=2 selects CMOS mode, brightness_mode=3 selects both EC
1157 and CMOS. The driver tries to auto-detect which interface to use.
1159 When display backlight brightness controls are available through the
1160 standard ACPI interface, it is best to use it instead of this direct
1161 ThinkPad-specific interface. The driver will disable its native
1162 backlight brightness control interface if it detects that the standard
1163 ACPI interface is available in the ThinkPad.
1165 The brightness_enable module parameter can be used to control whether
1166 the LCD brightness control feature will be enabled when available.
1167 brightness_enable=0 forces it to be disabled. brightness_enable=1
1168 forces it to be enabled when available, even if the standard ACPI
1169 interface is also available.
1173 The available commands are:
1175 echo up >/proc/acpi/ibm/brightness
1176 echo down >/proc/acpi/ibm/brightness
1177 echo 'level <level>' >/proc/acpi/ibm/brightness
1181 The interface is implemented through the backlight sysfs class, which is
1182 poorly documented at this time.
1184 Locate the thinkpad_screen device under /sys/class/backlight, and inside
1185 it there will be the following attributes:
1188 Reads the maximum brightness the hardware can be set to.
1189 The minimum is always zero.
1192 Reads what brightness the screen is set to at this instant.
1195 Writes request the driver to change brightness to the
1196 given value. Reads will tell you what brightness the
1197 driver is trying to set the display to when "power" is set
1198 to zero and the display has not been dimmed by a kernel
1199 power management event.
1202 power management mode, where 0 is "display on", and 1 to 3
1203 will dim the display backlight to brightness level 0
1204 because thinkpad-acpi cannot really turn the backlight
1205 off. Kernel power management events can temporarily
1206 increase the current power management level, i.e. they can
1212 Whatever you do, do NOT ever call thinkpad-acpi backlight-level change
1213 interface and the ACPI-based backlight level change interface
1214 (available on newer BIOSes, and driven by the Linux ACPI video driver)
1215 at the same time. The two will interact in bad ways, do funny things,
1216 and maybe reduce the life of the backlight lamps by needlessly kicking
1217 its level up and down at every change.
1220 Volume control -- /proc/acpi/ibm/volume
1221 ---------------------------------------
1223 This feature allows volume control on ThinkPad models which don't have
1224 a hardware volume knob. The available commands are:
1226 echo up >/proc/acpi/ibm/volume
1227 echo down >/proc/acpi/ibm/volume
1228 echo mute >/proc/acpi/ibm/volume
1229 echo 'level <level>' >/proc/acpi/ibm/volume
1231 The <level> number range is 0 to 15 although not all of them may be
1232 distinct. The unmute the volume after the mute command, use either the
1233 up or down command (the level command will not unmute the volume).
1234 The current volume level and mute state is shown in the file.
1236 The ALSA mixer interface to this feature is still missing, but patches
1237 to add it exist. That problem should be addressed in the not so
1241 Fan control and monitoring: fan speed, fan enable/disable
1242 ---------------------------------------------------------
1244 procfs: /proc/acpi/ibm/fan
1245 sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
1247 sysfs hwmon driver attributes: fan_watchdog
1249 NOTE NOTE NOTE: fan control operations are disabled by default for
1250 safety reasons. To enable them, the module parameter "fan_control=1"
1251 must be given to thinkpad-acpi.
1253 This feature attempts to show the current fan speed, control mode and
1254 other fan data that might be available. The speed is read directly
1255 from the hardware registers of the embedded controller. This is known
1256 to work on later R, T, X and Z series ThinkPads but may show a bogus
1257 value on other models.
1261 Most ThinkPad fans work in "levels" at the firmware interface. Level 0
1262 stops the fan. The higher the level, the higher the fan speed, although
1263 adjacent levels often map to the same fan speed. 7 is the highest
1264 level, where the fan reaches the maximum recommended speed.
1266 Level "auto" means the EC changes the fan level according to some
1267 internal algorithm, usually based on readings from the thermal sensors.
1269 There is also a "full-speed" level, also known as "disengaged" level.
1270 In this level, the EC disables the speed-locked closed-loop fan control,
1271 and drives the fan as fast as it can go, which might exceed hardware
1272 limits, so use this level with caution.
1274 The fan usually ramps up or down slowly from one speed to another, and
1275 it is normal for the EC to take several seconds to react to fan
1276 commands. The full-speed level may take up to two minutes to ramp up to
1277 maximum speed, and in some ThinkPads, the tachometer readings go stale
1278 while the EC is transitioning to the full-speed level.
1280 WARNING WARNING WARNING: do not leave the fan disabled unless you are
1281 monitoring all of the temperature sensor readings and you are ready to
1282 enable it if necessary to avoid overheating.
1284 An enabled fan in level "auto" may stop spinning if the EC decides the
1285 ThinkPad is cool enough and doesn't need the extra airflow. This is
1286 normal, and the EC will spin the fan up if the various thermal readings
1289 On the X40, this seems to depend on the CPU and HDD temperatures.
1290 Specifically, the fan is turned on when either the CPU temperature
1291 climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
1292 fan is turned off when the CPU temperature drops to 49 degrees and the
1293 HDD temperature drops to 41 degrees. These thresholds cannot
1294 currently be controlled.
1296 The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
1297 certain conditions are met. It will override any fan programming done
1298 through thinkpad-acpi.
1300 The thinkpad-acpi kernel driver can be programmed to revert the fan
1301 level to a safe setting if userspace does not issue one of the procfs
1302 fan commands: "enable", "disable", "level" or "watchdog", or if there
1303 are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
1304 set to 1, manual mode) within a configurable amount of time of up to
1305 120 seconds. This functionality is called fan safety watchdog.
1307 Note that the watchdog timer stops after it enables the fan. It will be
1308 rearmed again automatically (using the same interval) when one of the
1309 above mentioned fan commands is received. The fan watchdog is,
1310 therefore, not suitable to protect against fan mode changes made through
1311 means other than the "enable", "disable", and "level" procfs fan
1312 commands, or the hwmon fan control sysfs interface.
1316 The fan may be enabled or disabled with the following commands:
1318 echo enable >/proc/acpi/ibm/fan
1319 echo disable >/proc/acpi/ibm/fan
1321 Placing a fan on level 0 is the same as disabling it. Enabling a fan
1322 will try to place it in a safe level if it is too slow or disabled.
1324 The fan level can be controlled with the command:
1326 echo 'level <level>' > /proc/acpi/ibm/fan
1328 Where <level> is an integer from 0 to 7, or one of the words "auto" or
1329 "full-speed" (without the quotes). Not all ThinkPads support the "auto"
1330 and "full-speed" levels. The driver accepts "disengaged" as an alias for
1331 "full-speed", and reports it as "disengaged" for backwards
1334 On the X31 and X40 (and ONLY on those models), the fan speed can be
1335 controlled to a certain degree. Once the fan is running, it can be
1336 forced to run faster or slower with the following command:
1338 echo 'speed <speed>' > /proc/acpi/ibm/fan
1340 The sustainable range of fan speeds on the X40 appears to be from about
1341 3700 to about 7350. Values outside this range either do not have any
1342 effect or the fan speed eventually settles somewhere in that range. The
1343 fan cannot be stopped or started with this command. This functionality
1344 is incomplete, and not available through the sysfs interface.
1346 To program the safety watchdog, use the "watchdog" command.
1348 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
1350 If you want to disable the watchdog, use 0 as the interval.
1354 The sysfs interface follows the hwmon subsystem guidelines for the most
1355 part, and the exception is the fan safety watchdog.
1357 Writes to any of the sysfs attributes may return the EINVAL error if
1358 that operation is not supported in a given ThinkPad or if the parameter
1359 is out-of-bounds, and EPERM if it is forbidden. They may also return
1360 EINTR (interrupted system call), and EIO (I/O error while trying to talk
1363 Features not yet implemented by the driver return ENOSYS.
1365 hwmon device attribute pwm1_enable:
1366 0: PWM offline (fan is set to full-speed mode)
1367 1: Manual PWM control (use pwm1 to set fan level)
1368 2: Hardware PWM control (EC "auto" mode)
1369 3: reserved (Software PWM control, not implemented yet)
1371 Modes 0 and 2 are not supported by all ThinkPads, and the
1372 driver is not always able to detect this. If it does know a
1373 mode is unsupported, it will return -EINVAL.
1375 hwmon device attribute pwm1:
1376 Fan level, scaled from the firmware values of 0-7 to the hwmon
1377 scale of 0-255. 0 means fan stopped, 255 means highest normal
1380 This attribute only commands the fan if pmw1_enable is set to 1
1381 (manual PWM control).
1383 hwmon device attribute fan1_input:
1384 Fan tachometer reading, in RPM. May go stale on certain
1385 ThinkPads while the EC transitions the PWM to offline mode,
1386 which can take up to two minutes. May return rubbish on older
1389 hwmon driver attribute fan_watchdog:
1390 Fan safety watchdog timer interval, in seconds. Minimum is
1391 1 second, maximum is 120 seconds. 0 disables the watchdog.
1393 To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
1395 To start the fan in a safe mode: set pwm1_enable to 2. If that fails
1396 with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
1397 would be the safest choice, though).
1403 procfs: /proc/acpi/ibm/wan
1404 sysfs device attribute: wwan_enable (deprecated)
1405 sysfs rfkill class: switch "tpacpi_wwan_sw"
1407 This feature shows the presence and current state of the built-in
1408 Wireless WAN device.
1410 If the ThinkPad supports it, the WWAN state is stored in NVRAM,
1411 so it is kept across reboots and power-off.
1413 It was tested on a Lenovo ThinkPad X60. It should probably work on other
1414 ThinkPad models which come with this module installed.
1418 If the W-WAN card is installed, the following commands can be used:
1420 echo enable > /proc/acpi/ibm/wan
1421 echo disable > /proc/acpi/ibm/wan
1425 If the W-WAN card is installed, it can be enabled /
1426 disabled through the "wwan_enable" thinkpad-acpi device
1427 attribute, and its current status can also be queried.
1430 0: disables WWAN card / WWAN card is disabled
1431 1: enables WWAN card / WWAN card is enabled.
1433 Note: this interface has been superseded by the generic rfkill
1434 class. It has been deprecated, and it will be removed in year
1437 rfkill controller switch "tpacpi_wwan_sw": refer to
1438 Documentation/rfkill.txt for details.
1444 This feature is marked EXPERIMENTAL because it has not been extensively
1445 tested and validated in various ThinkPad models yet. The feature may not
1446 work as expected. USE WITH CAUTION! To use this feature, you need to supply
1447 the experimental=1 parameter when loading the module.
1449 sysfs rfkill class: switch "tpacpi_uwb_sw"
1451 This feature exports an rfkill controller for the UWB device, if one is
1452 present and enabled in the BIOS.
1456 rfkill controller switch "tpacpi_uwb_sw": refer to
1457 Documentation/rfkill.txt for details.
1460 Multiple Commands, Module Parameters
1461 ------------------------------------
1463 Multiple commands can be written to the proc files in one shot by
1464 separating them with commas, for example:
1466 echo enable,0xffff > /proc/acpi/ibm/hotkey
1467 echo lcd_disable,crt_enable > /proc/acpi/ibm/video
1469 Commands can also be specified when loading the thinkpad-acpi module,
1472 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
1475 Enabling debugging output
1476 -------------------------
1478 The module takes a debug parameter which can be used to selectively
1479 enable various classes of debugging output, for example:
1481 modprobe thinkpad_acpi debug=0xffff
1483 will enable all debugging output classes. It takes a bitmask, so
1484 to enable more than one output class, just add their values.
1486 Debug bitmask Description
1487 0x8000 Disclose PID of userspace programs
1488 accessing some functions of the driver
1489 0x0001 Initialization and probing
1492 There is also a kernel build option to enable more debugging
1493 information, which may be necessary to debug driver problems.
1495 The level of debugging information output by the driver can be changed
1496 at runtime through sysfs, using the driver attribute debug_level. The
1497 attribute takes the same bitmask as the debug module parameter above.
1500 Force loading of module
1501 -----------------------
1503 If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
1504 the module parameter force_load=1. Regardless of whether this works or
1505 not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
1508 Sysfs interface changelog:
1510 0x000100: Initial sysfs support, as a single platform driver and
1512 0x000200: Hot key support for 32 hot keys, and radio slider switch
1514 0x010000: Hot keys are now handled by default over the input
1515 layer, the radio switch generates input event EV_RADIO,
1516 and the driver enables hot key handling by default in
1519 0x020000: ABI fix: added a separate hwmon platform device and
1520 driver, which must be located by name (thinkpad)
1521 and the hwmon class for libsensors4 (lm-sensors 3)
1522 compatibility. Moved all hwmon attributes to this
1523 new platform device.
1525 0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
1526 support. If you must, use it to know you should not
1527 start a userspace NVRAM poller (allows to detect when
1528 NVRAM is compiled out by the user because it is
1529 unneeded/undesired in the first place).
1530 0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
1531 and proper hotkey_mask semantics (version 8 of the
1532 NVRAM polling patch). Some development snapshots of
1533 0.18 had an earlier version that did strange things
1536 0x020200: Add poll()/select() support to the following attributes:
1537 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason