1 ===========================
2 ThinkPad ACPI Extras Driver
3 ===========================
9 - Borislav Deianov <borislav@users.sf.net>
10 - Henrique de Moraes Holschuh <hmh@hmh.eng.br>
12 http://ibm-acpi.sf.net/
14 This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It
15 supports various features of these laptops which are accessible
16 through the ACPI and ACPI EC framework, but not otherwise fully
17 supported by the generic Linux ACPI drivers.
19 This driver used to be named ibm-acpi until kernel 2.6.21 and release
20 0.13-20070314. It used to be in the drivers/acpi tree, but it was
21 moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel
22 2.6.22, and release 0.14. It was moved to drivers/platform/x86 for
23 kernel 2.6.29 and release 0.22.
25 The driver is named "thinkpad-acpi". In some places, like module
26 names and log messages, "thinkpad_acpi" is used because of userspace
29 "tpacpi" is used as a shorthand where "thinkpad-acpi" would be too
30 long due to length limitations on some Linux kernel versions.
35 The features currently supported are the following (see below for
36 detailed description):
39 - Bluetooth enable and disable
40 - video output switching, expansion control
41 - ThinkLight on and off
46 - Experimental: embedded controller register dump
47 - LCD brightness control
49 - Fan control and monitoring: fan speed, fan enable/disable
50 - WAN enable and disable
51 - UWB enable and disable
53 A compatibility table by model and feature is maintained on the web
54 site, http://ibm-acpi.sf.net/. I appreciate any success or failure
55 reports, especially if they add to or correct the compatibility table.
56 Please include the following information in your report:
59 - a copy of your ACPI tables, using the "acpidump" utility
60 - a copy of the output of dmidecode, with serial numbers
62 - which driver features work and which don't
63 - the observed behavior of non-working features
65 Any other comments or patches are also more than welcome.
71 If you are compiling this driver as included in the Linux kernel
72 sources, look for the CONFIG_THINKPAD_ACPI Kconfig option.
73 It is located on the menu path: "Device Drivers" -> "X86 Platform
74 Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras".
80 The driver exports two different interfaces to userspace, which can be
81 used to access the features it provides. One is a legacy procfs-based
82 interface, which will be removed at some time in the future. The other
83 is a new sysfs-based interface which is not complete yet.
85 The procfs interface creates the /proc/acpi/ibm directory. There is a
86 file under that directory for each feature it supports. The procfs
87 interface is mostly frozen, and will change very little if at all: it
88 will not be extended to add any new functionality in the driver, instead
89 all new functionality will be implemented on the sysfs interface.
91 The sysfs interface tries to blend in the generic Linux sysfs subsystems
92 and classes as much as possible. Since some of these subsystems are not
93 yet ready or stabilized, it is expected that this interface will change,
94 and any and all userspace programs must deal with it.
97 Notes about the sysfs interface
98 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
100 Unlike what was done with the procfs interface, correctness when talking
101 to the sysfs interfaces will be enforced, as will correctness in the
102 thinkpad-acpi's implementation of sysfs interfaces.
104 Also, any bugs in the thinkpad-acpi sysfs driver code or in the
105 thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
106 maximum correctness, even if that means changing an interface in
107 non-compatible ways. As these interfaces mature both in the kernel and
108 in thinkpad-acpi, such changes should become quite rare.
110 Applications interfacing to the thinkpad-acpi sysfs interfaces must
111 follow all sysfs guidelines and correctly process all errors (the sysfs
112 interface makes extensive use of errors). File descriptors and open /
113 close operations to the sysfs inodes must also be properly implemented.
115 The version of thinkpad-acpi's sysfs interface is exported by the driver
116 as a driver attribute (see below).
118 Sysfs driver attributes are on the driver's sysfs attribute space,
119 for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and
120 /sys/bus/platform/drivers/thinkpad_hwmon/
122 Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
123 space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/.
125 Sysfs device attributes for the sensors and fan are on the
126 thinkpad_hwmon device's sysfs attribute space, but you should locate it
127 looking for a hwmon device with the name attribute of "thinkpad", or
128 better yet, through libsensors. For 4.14+ sysfs attributes were moved to the
129 hwmon device (/sys/bus/platform/devices/thinkpad_hwmon/hwmon/hwmon? or
130 /sys/class/hwmon/hwmon?).
135 procfs: /proc/acpi/ibm/driver
137 sysfs driver attribute: version
139 The driver name and version. No commands can be written to this file.
142 Sysfs interface version
143 -----------------------
145 sysfs driver attribute: interface_version
147 Version of the thinkpad-acpi sysfs interface, as an unsigned long
148 (output in hex format: 0xAAAABBCC), where:
157 The sysfs interface version changelog for the driver can be found at the
158 end of this document. Changes to the sysfs interface done by the kernel
159 subsystems are not documented here, nor are they tracked by this
162 Changes to the thinkpad-acpi sysfs interface are only considered
163 non-experimental when they are submitted to Linux mainline, at which
164 point the changes in this interface are documented and interface_version
165 may be updated. If you are using any thinkpad-acpi features not yet
166 sent to mainline for merging, you do so on your own risk: these features
167 may disappear, or be implemented in a different and incompatible way by
168 the time they are merged in Linux mainline.
170 Changes that are backwards-compatible by nature (e.g. the addition of
171 attributes that do not change the way the other attributes work) do not
172 always warrant an update of interface_version. Therefore, one must
173 expect that an attribute might not be there, and deal with it properly
174 (an attribute not being there *is* a valid way to make it clear that a
175 feature is not available in sysfs).
181 procfs: /proc/acpi/ibm/hotkey
183 sysfs device attribute: hotkey_*
185 In a ThinkPad, the ACPI HKEY handler is responsible for communicating
186 some important events and also keyboard hot key presses to the operating
187 system. Enabling the hotkey functionality of thinkpad-acpi signals the
188 firmware that such a driver is present, and modifies how the ThinkPad
189 firmware will behave in many situations.
191 The driver enables the HKEY ("hot key") event reporting automatically
192 when loaded, and disables it when it is removed.
194 The driver will report HKEY events in the following format::
196 ibm/hotkey HKEY 00000080 0000xxxx
198 Some of these events refer to hot key presses, but not all of them.
200 The driver will generate events over the input layer for hot keys and
201 radio switches, and over the ACPI netlink layer for other events. The
202 input layer support accepts the standard IOCTLs to remap the keycodes
203 assigned to each hot key.
205 The hot key bit mask allows some control over which hot keys generate
206 events. If a key is "masked" (bit set to 0 in the mask), the firmware
207 will handle it. If it is "unmasked", it signals the firmware that
208 thinkpad-acpi would prefer to handle it, if the firmware would be so
209 kind to allow it (and it often doesn't!).
211 Not all bits in the mask can be modified. Not all bits that can be
212 modified do anything. Not all hot keys can be individually controlled
213 by the mask. Some models do not support the mask at all. The behaviour
214 of the mask is, therefore, highly dependent on the ThinkPad model.
216 The driver will filter out any unmasked hotkeys, so even if the firmware
217 doesn't allow disabling an specific hotkey, the driver will not report
218 events for unmasked hotkeys.
220 Note that unmasking some keys prevents their default behavior. For
221 example, if Fn+F5 is unmasked, that key will no longer enable/disable
222 Bluetooth by itself in firmware.
224 Note also that not all Fn key combinations are supported through ACPI
225 depending on the ThinkPad model and firmware version. On those
226 ThinkPads, it is still possible to support some extra hotkeys by
227 polling the "CMOS NVRAM" at least 10 times per second. The driver
228 attempts to enables this functionality automatically when required.
233 The following commands can be written to the /proc/acpi/ibm/hotkey file::
235 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
236 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
237 ... any other 8-hex-digit mask ...
238 echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask
240 The following commands have been deprecated and will cause the kernel
243 echo enable > /proc/acpi/ibm/hotkey -- does nothing
244 echo disable > /proc/acpi/ibm/hotkey -- returns an error
246 The procfs interface does not support NVRAM polling control. So as to
247 maintain maximum bug-to-bug compatibility, it does not report any masks,
248 nor does it allow one to manipulate the hot key mask when the firmware
249 does not support masks at all, even if NVRAM polling is in use.
255 DEPRECATED, WILL BE REMOVED SOON.
260 DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE.
262 Returns the hot keys mask when thinkpad-acpi was loaded.
263 Upon module unload, the hot keys mask will be restored
264 to this value. This is always 0x80c, because those are
265 the hotkeys that were supported by ancient firmware
266 without mask support.
269 DEPRECATED, WILL BE REMOVED SOON.
275 bit mask to enable reporting (and depending on
276 the firmware, ACPI event generation) for each hot key
277 (see above). Returns the current status of the hot keys
278 mask, and allows one to modify it.
281 bit mask that should enable event reporting for all
282 supported hot keys, when echoed to hotkey_mask above.
283 Unless you know which events need to be handled
284 passively (because the firmware *will* handle them
285 anyway), do *not* use hotkey_all_mask. Use
286 hotkey_recommended_mask, instead. You have been warned.
288 hotkey_recommended_mask:
289 bit mask that should enable event reporting for all
290 supported hot keys, except those which are always
291 handled by the firmware anyway. Echo it to
292 hotkey_mask above, to use. This is the default mask
296 bit mask that selects which hot keys will the driver
297 poll the NVRAM for. This is auto-detected by the driver
298 based on the capabilities reported by the ACPI firmware,
299 but it can be overridden at runtime.
301 Hot keys whose bits are set in hotkey_source_mask are
302 polled for in NVRAM, and reported as hotkey events if
303 enabled in hotkey_mask. Only a few hot keys are
304 available through CMOS NVRAM polling.
306 Warning: when in NVRAM mode, the volume up/down/mute
307 keys are synthesized according to changes in the mixer,
308 which uses a single volume up or volume down hotkey
309 press to unmute, as per the ThinkPad volume mixer user
310 interface. When in ACPI event mode, volume up/down/mute
311 events are reported by the firmware and can behave
312 differently (and that behaviour changes with firmware
313 version -- not just with firmware models -- as well as
317 frequency in Hz for hot key polling. It must be between
318 0 and 25 Hz. Polling is only carried out when strictly
321 Setting hotkey_poll_freq to zero disables polling, and
322 will cause hot key presses that require NVRAM polling
323 to never be reported.
325 Setting hotkey_poll_freq too low may cause repeated
326 pressings of the same hot key to be misreported as a
327 single key press, or to not even be detected at all.
328 The recommended polling frequency is 10Hz.
331 If the ThinkPad has a hardware radio switch, this
332 attribute will read 0 if the switch is in the "radios
333 disabled" position, and 1 if the switch is in the
334 "radios enabled" position.
336 This attribute has poll()/select() support.
339 If the ThinkPad has tablet capabilities, this attribute
340 will read 0 if the ThinkPad is in normal mode, and
341 1 if the ThinkPad is in tablet mode.
343 This attribute has poll()/select() support.
346 Set to 1 if the system is waking up because the user
347 requested a bay ejection. Set to 2 if the system is
348 waking up because the user requested the system to
349 undock. Set to zero for normal wake-ups or wake-ups
350 due to unknown reasons.
352 This attribute has poll()/select() support.
354 wakeup_hotunplug_complete:
355 Set to 1 if the system was waken up because of an
356 undock or bay ejection request, and that request
357 was successfully completed. At this point, it might
358 be useful to send the system back to sleep, at the
359 user's choice. Refer to HKEY events 0x4003 and
362 This attribute has poll()/select() support.
367 A Hot key is mapped to a single input layer EV_KEY event, possibly
368 followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
369 code. An EV_SYN event will always be generated to mark the end of the
372 Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
373 used as a helper to remap keys, only. They are particularly useful when
374 remapping KEY_UNKNOWN keys.
376 The events are available in an input device, with the following id:
378 ============== ==============================
380 vendor 0x1014 (PCI_VENDOR_ID_IBM) or
381 0x17aa (PCI_VENDOR_ID_LENOVO)
382 product 0x5054 ("TP")
384 ============== ==============================
386 The version will have its LSB incremented if the keymap changes in a
387 backwards-compatible way. The MSB shall always be 0x41 for this input
388 device. If the MSB is not 0x41, do not use the device as described in
389 this section, as it is either something else (e.g. another input device
390 exported by a thinkpad driver, such as HDAPS) or its functionality has
391 been changed in a non-backwards compatible way.
393 Adding other event types for other functionalities shall be considered a
394 backwards-compatible change for this input device.
396 Thinkpad-acpi Hot Key event map (version 0x4101):
398 ======= ======= ============== ==============================================
401 ======= ======= ============== ==============================================
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
411 IBM: screen lock, often turns
412 off the ThinkLight as side-effect
415 0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
416 semantics, i.e. sleep-to-RAM).
417 It always generates some kind
418 of event, either the hot key
419 event or an ACPI sleep button
420 event. The firmware may
421 refuse to generate further FN+F4
422 key presses until a S3 or S4 ACPI
423 sleep cycle is performed or some
426 0x1005 0x04 FN+F5 Radio. Enables/disables
427 the internal Bluetooth hardware
428 and W-WAN card if left in control
429 of the firmware. Does not affect
431 Should be used to turn on/off all
432 radios (Bluetooth+W-WAN+WLAN),
437 0x1007 0x06 FN+F7 Video output cycle.
438 Do you feel lucky today?
440 0x1008 0x07 FN+F8 IBM: toggle screen expand
441 Lenovo: configure UltraNav,
442 or toggle screen expand
450 0x100C 0x0B FN+F12 Sleep to disk. You are always
451 supposed to handle it yourself,
452 either through the ACPI event,
453 or through a hotkey event.
454 The firmware may refuse to
455 generate further FN+F12 key
456 press events until a S3 or S4
457 ACPI sleep cycle is performed,
460 0x100D 0x0C FN+BACKSPACE -
461 0x100E 0x0D FN+INSERT -
462 0x100F 0x0E FN+DELETE -
464 0x1010 0x0F FN+HOME Brightness up. This key is
465 always handled by the firmware
466 in IBM ThinkPads, even when
467 unmasked. Just leave it alone.
468 For Lenovo ThinkPads with a new
469 BIOS, it has to be handled either
470 by the ACPI OSI, or by userspace.
471 The driver does the right thing,
472 never mess with this.
473 0x1011 0x10 FN+END Brightness down. See brightness
476 0x1012 0x11 FN+PGUP ThinkLight toggle. This key is
477 always handled by the firmware,
480 0x1013 0x12 FN+PGDOWN -
482 0x1014 0x13 FN+SPACE Zoom key
484 0x1015 0x14 VOLUME UP Internal mixer volume up. This
485 key is always handled by the
486 firmware, even when unmasked.
487 NOTE: Lenovo seems to be changing
489 0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
490 key is always handled by the
491 firmware, even when unmasked.
492 NOTE: Lenovo seems to be changing
494 0x1017 0x16 MUTE Mute internal mixer. This
495 key is always handled by the
496 firmware, even when unmasked.
498 0x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key
505 ======= ======= ============== ==============================================
507 The ThinkPad firmware does not allow one to differentiate when most hot
508 keys are pressed or released (either that, or we don't know how to, yet).
509 For these keys, the driver generates a set of events for a key press and
510 immediately issues the same set of events for a key release. It is
511 unknown by the driver if the ThinkPad firmware triggered these events on
512 hot key press or release, but the firmware will do it for either one, not
515 If a key is mapped to KEY_RESERVED, it generates no input events at all.
516 If a key is mapped to KEY_UNKNOWN, it generates an input event that
517 includes an scan code. If a key is mapped to anything else, it will
518 generate input device EV_KEY events.
520 In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
523 ============== ==============================================
524 SW_RFKILL_ALL T60 and later hardware rfkill rocker switch
525 SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
526 ============== ==============================================
528 Non hotkey ACPI HKEY event map
529 ------------------------------
531 Events that are never propagated by the driver:
533 ====== ==================================================
534 0x2304 System is waking up from suspend to undock
535 0x2305 System is waking up from suspend to eject bay
536 0x2404 System is waking up from hibernation to undock
537 0x2405 System is waking up from hibernation to eject bay
540 0x5009 Tablet swivel: switched to tablet mode
541 0x500A Tablet swivel: switched to normal mode
542 0x5010 Brightness level changed/control event
543 0x6000 KEYBOARD: Numlock key pressed
544 0x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED)
545 0x7000 Radio Switch may have changed state
546 ====== ==================================================
549 Events that are propagated by the driver to userspace:
551 ====== =====================================================
552 0x2313 ALARM: System is waking up from suspend because
553 the battery is nearly empty
554 0x2413 ALARM: System is waking up from hibernation because
555 the battery is nearly empty
556 0x3003 Bay ejection (see 0x2x05) complete, can sleep again
557 0x3006 Bay hotplug request (hint to power up SATA link when
558 the optical drive tray is ejected)
559 0x4003 Undocked (see 0x2x04), can sleep again
560 0x4010 Docked into hotplug port replicator (non-ACPI dock)
561 0x4011 Undocked from hotplug port replicator (non-ACPI dock)
562 0x500B Tablet pen inserted into its storage bay
563 0x500C Tablet pen removed from its storage bay
564 0x6011 ALARM: battery is too hot
565 0x6012 ALARM: battery is extremely hot
566 0x6021 ALARM: a sensor is too hot
567 0x6022 ALARM: a sensor is extremely hot
568 0x6030 System thermal table changed
569 0x6032 Thermal Control command set completion (DYTC, Windows)
570 0x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED)
571 0x60C0 X1 Yoga 2016, Tablet mode status changed
572 0x60F0 Thermal Transformation changed (GMTS, Windows)
573 ====== =====================================================
575 Battery nearly empty alarms are a last resort attempt to get the
576 operating system to hibernate or shutdown cleanly (0x2313), or shutdown
577 cleanly (0x2413) before power is lost. They must be acted upon, as the
578 wake up caused by the firmware will have negated most safety nets...
580 When any of the "too hot" alarms happen, according to Lenovo the user
581 should suspend or hibernate the laptop (and in the case of battery
582 alarms, unplug the AC adapter) to let it cool down. These alarms do
583 signal that something is wrong, they should never happen on normal
584 operating conditions.
586 The "extremely hot" alarms are emergencies. According to Lenovo, the
587 operating system is to force either an immediate suspend or hibernate
588 cycle, or a system shutdown. Obviously, something is very wrong if this
592 Brightness hotkey notes
593 ^^^^^^^^^^^^^^^^^^^^^^^
595 Don't mess with the brightness hotkeys in a Thinkpad. If you want
596 notifications for OSD, use the sysfs backlight class event support.
598 The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
599 automatically for the cases were userspace has to do something to
600 implement brightness changes. When you override these events, you will
601 either fail to handle properly the ThinkPads that require explicit
602 action to change backlight brightness, or the ThinkPads that require
603 that no action be taken to work properly.
609 procfs: /proc/acpi/ibm/bluetooth
611 sysfs device attribute: bluetooth_enable (deprecated)
613 sysfs rfkill class: switch "tpacpi_bluetooth_sw"
615 This feature shows the presence and current state of a ThinkPad
616 Bluetooth device in the internal ThinkPad CDC slot.
618 If the ThinkPad supports it, the Bluetooth state is stored in NVRAM,
619 so it is kept across reboots and power-off.
624 If Bluetooth is installed, the following commands can be used::
626 echo enable > /proc/acpi/ibm/bluetooth
627 echo disable > /proc/acpi/ibm/bluetooth
632 If the Bluetooth CDC card is installed, it can be enabled /
633 disabled through the "bluetooth_enable" thinkpad-acpi device
634 attribute, and its current status can also be queried.
638 - 0: disables Bluetooth / Bluetooth is disabled
639 - 1: enables Bluetooth / Bluetooth is enabled.
641 Note: this interface has been superseded by the generic rfkill
642 class. It has been deprecated, and it will be removed in year
645 rfkill controller switch "tpacpi_bluetooth_sw": refer to
646 Documentation/driver-api/rfkill.rst for details.
649 Video output control -- /proc/acpi/ibm/video
650 --------------------------------------------
652 This feature allows control over the devices used for video output -
653 LCD, CRT or DVI (if available). The following commands are available::
655 echo lcd_enable > /proc/acpi/ibm/video
656 echo lcd_disable > /proc/acpi/ibm/video
657 echo crt_enable > /proc/acpi/ibm/video
658 echo crt_disable > /proc/acpi/ibm/video
659 echo dvi_enable > /proc/acpi/ibm/video
660 echo dvi_disable > /proc/acpi/ibm/video
661 echo auto_enable > /proc/acpi/ibm/video
662 echo auto_disable > /proc/acpi/ibm/video
663 echo expand_toggle > /proc/acpi/ibm/video
664 echo video_switch > /proc/acpi/ibm/video
667 Access to this feature is restricted to processes owning the
668 CAP_SYS_ADMIN capability for safety reasons, as it can interact badly
669 enough with some versions of X.org to crash it.
671 Each video output device can be enabled or disabled individually.
672 Reading /proc/acpi/ibm/video shows the status of each device.
674 Automatic video switching can be enabled or disabled. When automatic
675 video switching is enabled, certain events (e.g. opening the lid,
676 docking or undocking) cause the video output device to change
677 automatically. While this can be useful, it also causes flickering
678 and, on the X40, video corruption. By disabling automatic switching,
679 the flickering or video corruption can be avoided.
681 The video_switch command cycles through the available video outputs
682 (it simulates the behavior of Fn-F7).
684 Video expansion can be toggled through this feature. This controls
685 whether the display is expanded to fill the entire LCD screen when a
686 mode with less than full resolution is used. Note that the current
687 video expansion status cannot be determined through this feature.
689 Note that on many models (particularly those using Radeon graphics
690 chips) the X driver configures the video card in a way which prevents
691 Fn-F7 from working. This also disables the video output switching
692 features of this driver, as it uses the same ACPI methods as
693 Fn-F7. Video switching on the console should still work.
695 UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000
701 procfs: /proc/acpi/ibm/light
703 sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
708 The ThinkLight status can be read and set through the procfs interface. A
709 few models which do not make the status available will show the ThinkLight
710 status as "unknown". The available commands are::
712 echo on > /proc/acpi/ibm/light
713 echo off > /proc/acpi/ibm/light
718 The ThinkLight sysfs interface is documented by the LED class
719 documentation, in Documentation/leds/leds-class.rst. The ThinkLight LED name
720 is "tpacpi::thinklight".
722 Due to limitations in the sysfs LED class, if the status of the ThinkLight
723 cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
724 It is impossible to know if the status returned through sysfs is valid.
730 procfs: /proc/acpi/ibm/cmos
732 sysfs device attribute: cmos_command
734 This feature is mostly used internally by the ACPI firmware to keep the legacy
735 CMOS NVRAM bits in sync with the current machine state, and to record this
736 state so that the ThinkPad will retain such settings across reboots.
738 Some of these commands actually perform actions in some ThinkPad models, but
739 this is expected to disappear more and more in newer models. As an example, in
740 a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
741 real, but commands 0 to 2 don't control the mixer anymore (they have been
742 phased out) and just update the NVRAM.
744 The range of valid cmos command numbers is 0 to 21, but not all have an
745 effect and the behavior varies from model to model. Here is the behavior
746 on the X40 (tpb is the ThinkPad Buttons utility):
748 - 0 - Related to "Volume down" key press
749 - 1 - Related to "Volume up" key press
750 - 2 - Related to "Mute on" key press
751 - 3 - Related to "Access IBM" key press
752 - 4 - Related to "LCD brightness up" key press
753 - 5 - Related to "LCD brightness down" key press
754 - 11 - Related to "toggle screen expansion" key press/function
755 - 12 - Related to "ThinkLight on"
756 - 13 - Related to "ThinkLight off"
757 - 14 - Related to "ThinkLight" key press (toggle ThinkLight)
759 The cmos command interface is prone to firmware split-brain problems, as
760 in newer ThinkPads it is just a compatibility layer. Do not use it, it is
761 exported just as a debug tool.
767 procfs: /proc/acpi/ibm/led
768 sysfs attributes: as per LED class, see below for names
770 Some of the LED indicators can be controlled through this feature. On
771 some older ThinkPad models, it is possible to query the status of the
772 LED indicators as well. Newer ThinkPads cannot query the real status
773 of the LED indicators.
775 Because misuse of the LEDs could induce an unaware user to perform
776 dangerous actions (like undocking or ejecting a bay device while the
777 buses are still active), or mask an important alarm (such as a nearly
778 empty battery, or a broken battery), access to most LEDs is
781 Unrestricted access to all LEDs requires that thinkpad-acpi be
782 compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled.
783 Distributions must never enable this option. Individual users that
784 are aware of the consequences are welcome to enabling it.
786 Audio mute and microphone mute LEDs are supported, but currently not
787 visible to userspace. They are used by the snd-hda-intel audio driver.
792 The available commands are::
794 echo '<LED number> on' >/proc/acpi/ibm/led
795 echo '<LED number> off' >/proc/acpi/ibm/led
796 echo '<LED number> blink' >/proc/acpi/ibm/led
798 The <LED number> range is 0 to 15. The set of LEDs that can be
799 controlled varies from model to model. Here is the common ThinkPad
803 - 1 - battery (orange)
804 - 2 - battery (green)
807 - 5 - UltraBase battery slot
814 - 13, 14, 15 - (unknown)
816 All of the above can be turned on and off and can be made to blink.
821 The ThinkPad LED sysfs interface is described in detail by the LED class
822 documentation, in Documentation/leds/leds-class.rst.
824 The LEDs are named (in LED ID order, from 0 to 12):
825 "tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
826 "tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
827 "tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1",
828 "tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3",
829 "tpacpi::thinkvantage".
831 Due to limitations in the sysfs LED class, if the status of the LED
832 indicators cannot be read due to an error, thinkpad-acpi will report it as
833 a brightness of zero (same as LED off).
835 If the thinkpad firmware doesn't support reading the current status,
836 trying to read the current LED brightness will just return whatever
837 brightness was last written to that attribute.
839 These LEDs can blink using hardware acceleration. To request that a
840 ThinkPad indicator LED should blink in hardware accelerated mode, use the
841 "timer" trigger, and leave the delay_on and delay_off parameters set to
842 zero (to request hardware acceleration autodetection).
844 LEDs that are known not to exist in a given ThinkPad model are not
845 made available through the sysfs interface. If you have a dock and you
846 notice there are LEDs listed for your ThinkPad that do not exist (and
847 are not in the dock), or if you notice that there are missing LEDs,
848 a report to ibm-acpi-devel@lists.sourceforge.net is appreciated.
851 ACPI sounds -- /proc/acpi/ibm/beep
852 ----------------------------------
854 The BEEP method is used internally by the ACPI firmware to provide
855 audible alerts in various situations. This feature allows the same
856 sounds to be triggered manually.
858 The commands are non-negative integer numbers::
860 echo <number> >/proc/acpi/ibm/beep
862 The valid <number> range is 0 to 17. Not all numbers trigger sounds
863 and the sounds vary from model to model. Here is the behavior on the
866 - 0 - stop a sound in progress (but use 17 to stop 16)
867 - 2 - two beeps, pause, third beep ("low battery")
869 - 4 - high, followed by low-pitched beep ("unable")
871 - 6 - very high, followed by high-pitched beep ("AC/DC")
872 - 7 - high-pitched beep
873 - 9 - three short beeps
874 - 10 - very long beep
875 - 12 - low-pitched beep
876 - 15 - three high-pitched beeps repeating constantly, stop with 0
877 - 16 - one medium-pitched beep repeating constantly, stop with 17
884 procfs: /proc/acpi/ibm/thermal
886 sysfs device attributes: (hwmon "thinkpad") temp*_input
888 Most ThinkPads include six or more separate temperature sensors but only
889 expose the CPU temperature through the standard ACPI methods. This
890 feature shows readings from up to eight different sensors on older
891 ThinkPads, and up to sixteen different sensors on newer ThinkPads.
893 For example, on the X40, a typical output may be:
896 42 42 45 41 36 -128 33 -128
898 On the T43/p, a typical output may be:
901 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
903 The mapping of thermal sensors to physical locations varies depending on
904 system-board model (and thus, on ThinkPad model).
906 http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
907 tries to track down these locations for various models.
909 Most (newer?) models seem to follow this pattern:
912 - 2: (depends on model)
913 - 3: (depends on model)
915 - 5: Main battery: main sensor
916 - 6: Bay battery: main sensor
917 - 7: Main battery: secondary sensor
918 - 8: Bay battery: secondary sensor
919 - 9-15: (depends on model)
921 For the R51 (source: Thomas Gruber):
926 For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
927 http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
929 - 2: System board, left side (near PCMCIA slot), reported as HDAPS temp
931 - 9: MCH (northbridge) to DRAM Bus
932 - 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
934 - 11: Power regulator, underside of system board, below F2 key
936 The A31 has a very atypical layout for the thermal sensors
937 (source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
940 - 2: Main Battery: main sensor
942 - 4: Bay Battery: main sensor
943 - 5: MCH (northbridge)
945 - 7: Main Battery: secondary sensor
946 - 8: Bay Battery: secondary sensor
952 Readings from sensors that are not available return -128.
953 No commands can be written to this file.
958 Sensors that are not available return the ENXIO error. This
959 status may change at runtime, as there are hotplug thermal
960 sensors, like those inside the batteries and docks.
962 thinkpad-acpi thermal sensors are reported through the hwmon
963 subsystem, and follow all of the hwmon guidelines at
966 EXPERIMENTAL: Embedded controller register dump
967 -----------------------------------------------
969 This feature is not included in the thinkpad driver anymore.
970 Instead the EC can be accessed through /sys/kernel/debug/ec with
971 a userspace tool which can be found here:
972 ftp://ftp.suse.com/pub/people/trenn/sources/ec
974 Use it to determine the register holding the fan
975 speed on some models. To do that, do the following:
977 - make sure the battery is fully charged
978 - make sure the fan is running
979 - use above mentioned tool to read out the EC
981 Often fan and temperature values vary between
982 readings. Since temperatures don't change vary fast, you can take
983 several quick dumps to eliminate them.
985 You can use a similar method to figure out the meaning of other
986 embedded controller registers - e.g. make sure nothing else changes
987 except the charging or discharging battery to determine which
988 registers contain the current battery capacity, etc. If you experiment
989 with this, do send me your results (including some complete dumps with
990 a description of the conditions when they were taken.)
993 LCD brightness control
994 ----------------------
996 procfs: /proc/acpi/ibm/brightness
998 sysfs backlight device "thinkpad_screen"
1000 This feature allows software control of the LCD brightness on ThinkPad
1001 models which don't have a hardware brightness slider.
1003 It has some limitations: the LCD backlight cannot be actually turned
1004 on or off by this interface, it just controls the backlight brightness
1007 On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
1008 has eight brightness levels, ranging from 0 to 7. Some of the levels
1009 may not be distinct. Later Lenovo models that implement the ACPI
1010 display backlight brightness control methods have 16 levels, ranging
1013 For IBM ThinkPads, there are two interfaces to the firmware for direct
1014 brightness control, EC and UCMS (or CMOS). To select which one should be
1015 used, use the brightness_mode module parameter: brightness_mode=1 selects
1016 EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC
1017 mode with NVRAM backing (so that brightness changes are remembered across
1020 The driver tries to select which interface to use from a table of
1021 defaults for each ThinkPad model. If it makes a wrong choice, please
1022 report this as a bug, so that we can fix it.
1024 Lenovo ThinkPads only support brightness_mode=2 (UCMS).
1026 When display backlight brightness controls are available through the
1027 standard ACPI interface, it is best to use it instead of this direct
1028 ThinkPad-specific interface. The driver will disable its native
1029 backlight brightness control interface if it detects that the standard
1030 ACPI interface is available in the ThinkPad.
1032 If you want to use the thinkpad-acpi backlight brightness control
1033 instead of the generic ACPI video backlight brightness control for some
1034 reason, you should use the acpi_backlight=vendor kernel parameter.
1036 The brightness_enable module parameter can be used to control whether
1037 the LCD brightness control feature will be enabled when available.
1038 brightness_enable=0 forces it to be disabled. brightness_enable=1
1039 forces it to be enabled when available, even if the standard ACPI
1040 interface is also available.
1045 The available commands are::
1047 echo up >/proc/acpi/ibm/brightness
1048 echo down >/proc/acpi/ibm/brightness
1049 echo 'level <level>' >/proc/acpi/ibm/brightness
1054 The interface is implemented through the backlight sysfs class, which is
1055 poorly documented at this time.
1057 Locate the thinkpad_screen device under /sys/class/backlight, and inside
1058 it there will be the following attributes:
1061 Reads the maximum brightness the hardware can be set to.
1062 The minimum is always zero.
1065 Reads what brightness the screen is set to at this instant.
1068 Writes request the driver to change brightness to the
1069 given value. Reads will tell you what brightness the
1070 driver is trying to set the display to when "power" is set
1071 to zero and the display has not been dimmed by a kernel
1072 power management event.
1075 power management mode, where 0 is "display on", and 1 to 3
1076 will dim the display backlight to brightness level 0
1077 because thinkpad-acpi cannot really turn the backlight
1078 off. Kernel power management events can temporarily
1079 increase the current power management level, i.e. they can
1085 Whatever you do, do NOT ever call thinkpad-acpi backlight-level change
1086 interface and the ACPI-based backlight level change interface
1087 (available on newer BIOSes, and driven by the Linux ACPI video driver)
1088 at the same time. The two will interact in bad ways, do funny things,
1089 and maybe reduce the life of the backlight lamps by needlessly kicking
1090 its level up and down at every change.
1093 Volume control (Console Audio control)
1094 --------------------------------------
1096 procfs: /proc/acpi/ibm/volume
1098 ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC"
1100 NOTE: by default, the volume control interface operates in read-only
1101 mode, as it is supposed to be used for on-screen-display purposes.
1102 The read/write mode can be enabled through the use of the
1103 "volume_control=1" module parameter.
1105 NOTE: distros are urged to not enable volume_control by default, this
1106 should be done by the local admin only. The ThinkPad UI is for the
1107 console audio control to be done through the volume keys only, and for
1108 the desktop environment to just provide on-screen-display feedback.
1109 Software volume control should be done only in the main AC97/HDA
1113 About the ThinkPad Console Audio control
1114 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1116 ThinkPads have a built-in amplifier and muting circuit that drives the
1117 console headphone and speakers. This circuit is after the main AC97
1118 or HDA mixer in the audio path, and under exclusive control of the
1121 ThinkPads have three special hotkeys to interact with the console
1122 audio control: volume up, volume down and mute.
1124 It is worth noting that the normal way the mute function works (on
1125 ThinkPads that do not have a "mute LED") is:
1127 1. Press mute to mute. It will *always* mute, you can press it as
1128 many times as you want, and the sound will remain mute.
1130 2. Press either volume key to unmute the ThinkPad (it will _not_
1131 change the volume, it will just unmute).
1133 This is a very superior design when compared to the cheap software-only
1134 mute-toggle solution found on normal consumer laptops: you can be
1135 absolutely sure the ThinkPad will not make noise if you press the mute
1136 button, no matter the previous state.
1138 The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain
1139 amplifiers driving the speakers and headphone output, and the firmware
1140 also handles volume control for the headphone and speakers on these
1141 ThinkPads without any help from the operating system (this volume
1142 control stage exists after the main AC97 or HDA mixer in the audio
1145 The newer Lenovo models only have firmware mute control, and depend on
1146 the main HDA mixer to do volume control (which is done by the operating
1147 system). In this case, the volume keys are filtered out for unmute
1148 key press (there are some firmware bugs in this area) and delivered as
1149 normal key presses to the operating system (thinkpad-acpi is not
1153 The ThinkPad-ACPI volume control
1154 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1156 The preferred way to interact with the Console Audio control is the
1159 The legacy procfs interface allows one to read the current state,
1160 and if volume control is enabled, accepts the following commands::
1162 echo up >/proc/acpi/ibm/volume
1163 echo down >/proc/acpi/ibm/volume
1164 echo mute >/proc/acpi/ibm/volume
1165 echo unmute >/proc/acpi/ibm/volume
1166 echo 'level <level>' >/proc/acpi/ibm/volume
1168 The <level> number range is 0 to 14 although not all of them may be
1169 distinct. To unmute the volume after the mute command, use either the
1170 up or down command (the level command will not unmute the volume), or
1173 You can use the volume_capabilities parameter to tell the driver
1174 whether your thinkpad has volume control or mute-only control:
1175 volume_capabilities=1 for mixers with mute and volume control,
1176 volume_capabilities=2 for mixers with only mute control.
1178 If the driver misdetects the capabilities for your ThinkPad model,
1179 please report this to ibm-acpi-devel@lists.sourceforge.net, so that we
1180 can update the driver.
1182 There are two strategies for volume control. To select which one
1183 should be used, use the volume_mode module parameter: volume_mode=1
1184 selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing
1185 (so that volume/mute changes are remembered across shutdown/reboot).
1187 The driver will operate in volume_mode=3 by default. If that does not
1188 work well on your ThinkPad model, please report this to
1189 ibm-acpi-devel@lists.sourceforge.net.
1191 The driver supports the standard ALSA module parameters. If the ALSA
1192 mixer is disabled, the driver will disable all volume functionality.
1195 Fan control and monitoring: fan speed, fan enable/disable
1196 ---------------------------------------------------------
1198 procfs: /proc/acpi/ibm/fan
1200 sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1, pwm1_enable, fan2_input
1202 sysfs hwmon driver attributes: fan_watchdog
1205 fan control operations are disabled by default for
1206 safety reasons. To enable them, the module parameter "fan_control=1"
1207 must be given to thinkpad-acpi.
1209 This feature attempts to show the current fan speed, control mode and
1210 other fan data that might be available. The speed is read directly
1211 from the hardware registers of the embedded controller. This is known
1212 to work on later R, T, X and Z series ThinkPads but may show a bogus
1213 value on other models.
1215 Some Lenovo ThinkPads support a secondary fan. This fan cannot be
1216 controlled separately, it shares the main fan control.
1221 Most ThinkPad fans work in "levels" at the firmware interface. Level 0
1222 stops the fan. The higher the level, the higher the fan speed, although
1223 adjacent levels often map to the same fan speed. 7 is the highest
1224 level, where the fan reaches the maximum recommended speed.
1226 Level "auto" means the EC changes the fan level according to some
1227 internal algorithm, usually based on readings from the thermal sensors.
1229 There is also a "full-speed" level, also known as "disengaged" level.
1230 In this level, the EC disables the speed-locked closed-loop fan control,
1231 and drives the fan as fast as it can go, which might exceed hardware
1232 limits, so use this level with caution.
1234 The fan usually ramps up or down slowly from one speed to another, and
1235 it is normal for the EC to take several seconds to react to fan
1236 commands. The full-speed level may take up to two minutes to ramp up to
1237 maximum speed, and in some ThinkPads, the tachometer readings go stale
1238 while the EC is transitioning to the full-speed level.
1240 WARNING WARNING WARNING: do not leave the fan disabled unless you are
1241 monitoring all of the temperature sensor readings and you are ready to
1242 enable it if necessary to avoid overheating.
1244 An enabled fan in level "auto" may stop spinning if the EC decides the
1245 ThinkPad is cool enough and doesn't need the extra airflow. This is
1246 normal, and the EC will spin the fan up if the various thermal readings
1249 On the X40, this seems to depend on the CPU and HDD temperatures.
1250 Specifically, the fan is turned on when either the CPU temperature
1251 climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
1252 fan is turned off when the CPU temperature drops to 49 degrees and the
1253 HDD temperature drops to 41 degrees. These thresholds cannot
1254 currently be controlled.
1256 The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
1257 certain conditions are met. It will override any fan programming done
1258 through thinkpad-acpi.
1260 The thinkpad-acpi kernel driver can be programmed to revert the fan
1261 level to a safe setting if userspace does not issue one of the procfs
1262 fan commands: "enable", "disable", "level" or "watchdog", or if there
1263 are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
1264 set to 1, manual mode) within a configurable amount of time of up to
1265 120 seconds. This functionality is called fan safety watchdog.
1267 Note that the watchdog timer stops after it enables the fan. It will be
1268 rearmed again automatically (using the same interval) when one of the
1269 above mentioned fan commands is received. The fan watchdog is,
1270 therefore, not suitable to protect against fan mode changes made through
1271 means other than the "enable", "disable", and "level" procfs fan
1272 commands, or the hwmon fan control sysfs interface.
1277 The fan may be enabled or disabled with the following commands::
1279 echo enable >/proc/acpi/ibm/fan
1280 echo disable >/proc/acpi/ibm/fan
1282 Placing a fan on level 0 is the same as disabling it. Enabling a fan
1283 will try to place it in a safe level if it is too slow or disabled.
1285 The fan level can be controlled with the command::
1287 echo 'level <level>' > /proc/acpi/ibm/fan
1289 Where <level> is an integer from 0 to 7, or one of the words "auto" or
1290 "full-speed" (without the quotes). Not all ThinkPads support the "auto"
1291 and "full-speed" levels. The driver accepts "disengaged" as an alias for
1292 "full-speed", and reports it as "disengaged" for backwards
1295 On the X31 and X40 (and ONLY on those models), the fan speed can be
1296 controlled to a certain degree. Once the fan is running, it can be
1297 forced to run faster or slower with the following command::
1299 echo 'speed <speed>' > /proc/acpi/ibm/fan
1301 The sustainable range of fan speeds on the X40 appears to be from about
1302 3700 to about 7350. Values outside this range either do not have any
1303 effect or the fan speed eventually settles somewhere in that range. The
1304 fan cannot be stopped or started with this command. This functionality
1305 is incomplete, and not available through the sysfs interface.
1307 To program the safety watchdog, use the "watchdog" command::
1309 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
1311 If you want to disable the watchdog, use 0 as the interval.
1316 The sysfs interface follows the hwmon subsystem guidelines for the most
1317 part, and the exception is the fan safety watchdog.
1319 Writes to any of the sysfs attributes may return the EINVAL error if
1320 that operation is not supported in a given ThinkPad or if the parameter
1321 is out-of-bounds, and EPERM if it is forbidden. They may also return
1322 EINTR (interrupted system call), and EIO (I/O error while trying to talk
1325 Features not yet implemented by the driver return ENOSYS.
1327 hwmon device attribute pwm1_enable:
1328 - 0: PWM offline (fan is set to full-speed mode)
1329 - 1: Manual PWM control (use pwm1 to set fan level)
1330 - 2: Hardware PWM control (EC "auto" mode)
1331 - 3: reserved (Software PWM control, not implemented yet)
1333 Modes 0 and 2 are not supported by all ThinkPads, and the
1334 driver is not always able to detect this. If it does know a
1335 mode is unsupported, it will return -EINVAL.
1337 hwmon device attribute pwm1:
1338 Fan level, scaled from the firmware values of 0-7 to the hwmon
1339 scale of 0-255. 0 means fan stopped, 255 means highest normal
1342 This attribute only commands the fan if pmw1_enable is set to 1
1343 (manual PWM control).
1345 hwmon device attribute fan1_input:
1346 Fan tachometer reading, in RPM. May go stale on certain
1347 ThinkPads while the EC transitions the PWM to offline mode,
1348 which can take up to two minutes. May return rubbish on older
1351 hwmon device attribute fan2_input:
1352 Fan tachometer reading, in RPM, for the secondary fan.
1353 Available only on some ThinkPads. If the secondary fan is
1354 not installed, will always read 0.
1356 hwmon driver attribute fan_watchdog:
1357 Fan safety watchdog timer interval, in seconds. Minimum is
1358 1 second, maximum is 120 seconds. 0 disables the watchdog.
1360 To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
1362 To start the fan in a safe mode: set pwm1_enable to 2. If that fails
1363 with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
1364 would be the safest choice, though).
1370 procfs: /proc/acpi/ibm/wan
1372 sysfs device attribute: wwan_enable (deprecated)
1374 sysfs rfkill class: switch "tpacpi_wwan_sw"
1376 This feature shows the presence and current state of the built-in
1377 Wireless WAN device.
1379 If the ThinkPad supports it, the WWAN state is stored in NVRAM,
1380 so it is kept across reboots and power-off.
1382 It was tested on a Lenovo ThinkPad X60. It should probably work on other
1383 ThinkPad models which come with this module installed.
1388 If the W-WAN card is installed, the following commands can be used::
1390 echo enable > /proc/acpi/ibm/wan
1391 echo disable > /proc/acpi/ibm/wan
1396 If the W-WAN card is installed, it can be enabled /
1397 disabled through the "wwan_enable" thinkpad-acpi device
1398 attribute, and its current status can also be queried.
1401 - 0: disables WWAN card / WWAN card is disabled
1402 - 1: enables WWAN card / WWAN card is enabled.
1404 Note: this interface has been superseded by the generic rfkill
1405 class. It has been deprecated, and it will be removed in year
1408 rfkill controller switch "tpacpi_wwan_sw": refer to
1409 Documentation/driver-api/rfkill.rst for details.
1415 This feature is considered EXPERIMENTAL because it has not been extensively
1416 tested and validated in various ThinkPad models yet. The feature may not
1417 work as expected. USE WITH CAUTION! To use this feature, you need to supply
1418 the experimental=1 parameter when loading the module.
1420 sysfs rfkill class: switch "tpacpi_uwb_sw"
1422 This feature exports an rfkill controller for the UWB device, if one is
1423 present and enabled in the BIOS.
1428 rfkill controller switch "tpacpi_uwb_sw": refer to
1429 Documentation/driver-api/rfkill.rst for details.
1434 sysfs device attribute: adaptive_kbd_mode
1436 This sysfs attribute controls the keyboard "face" that will be shown on the
1437 Lenovo X1 Carbon 2nd gen (2014)'s adaptive keyboard. The value can be read
1441 - 2 = Web-browser mode
1442 - 3 = Web-conference mode
1446 For more details about which buttons will appear depending on the mode, please
1447 review the laptop's user guide:
1448 http://www.lenovo.com/shop/americas/content/user_guides/x1carbon_2_ug_en.pdf
1450 Multiple Commands, Module Parameters
1451 ------------------------------------
1453 Multiple commands can be written to the proc files in one shot by
1454 separating them with commas, for example::
1456 echo enable,0xffff > /proc/acpi/ibm/hotkey
1457 echo lcd_disable,crt_enable > /proc/acpi/ibm/video
1459 Commands can also be specified when loading the thinkpad-acpi module,
1462 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
1465 Enabling debugging output
1466 -------------------------
1468 The module takes a debug parameter which can be used to selectively
1469 enable various classes of debugging output, for example::
1471 modprobe thinkpad_acpi debug=0xffff
1473 will enable all debugging output classes. It takes a bitmask, so
1474 to enable more than one output class, just add their values.
1476 ============= ======================================
1477 Debug bitmask Description
1478 ============= ======================================
1479 0x8000 Disclose PID of userspace programs
1480 accessing some functions of the driver
1481 0x0001 Initialization and probing
1483 0x0004 RF Transmitter control (RFKILL)
1484 (bluetooth, WWAN, UWB...)
1485 0x0008 HKEY event interface, hotkeys
1487 0x0020 Backlight brightness
1488 0x0040 Audio mixer/volume control
1489 ============= ======================================
1491 There is also a kernel build option to enable more debugging
1492 information, which may be necessary to debug driver problems.
1494 The level of debugging information output by the driver can be changed
1495 at runtime through sysfs, using the driver attribute debug_level. The
1496 attribute takes the same bitmask as the debug module parameter above.
1499 Force loading of module
1500 -----------------------
1502 If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
1503 the module parameter force_load=1. Regardless of whether this works or
1504 not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
1507 Sysfs interface changelog
1508 ^^^^^^^^^^^^^^^^^^^^^^^^^
1510 ========= ===============================================================
1511 0x000100: Initial sysfs support, as a single platform driver and
1513 0x000200: Hot key support for 32 hot keys, and radio slider switch
1515 0x010000: Hot keys are now handled by default over the input
1516 layer, the radio switch generates input event EV_RADIO,
1517 and the driver enables hot key handling by default in
1520 0x020000: ABI fix: added a separate hwmon platform device and
1521 driver, which must be located by name (thinkpad)
1522 and the hwmon class for libsensors4 (lm-sensors 3)
1523 compatibility. Moved all hwmon attributes to this
1524 new platform device.
1526 0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
1527 support. If you must, use it to know you should not
1528 start a userspace NVRAM poller (allows to detect when
1529 NVRAM is compiled out by the user because it is
1530 unneeded/undesired in the first place).
1531 0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
1532 and proper hotkey_mask semantics (version 8 of the
1533 NVRAM polling patch). Some development snapshots of
1534 0.18 had an earlier version that did strange things
1537 0x020200: Add poll()/select() support to the following attributes:
1538 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason
1540 0x020300: hotkey enable/disable support removed, attributes
1541 hotkey_bios_enabled and hotkey_enable deprecated and
1544 0x020400: Marker for 16 LEDs support. Also, LEDs that are known
1545 to not exist in a given model are not registered with
1546 the LED sysfs class anymore.
1548 0x020500: Updated hotkey driver, hotkey_mask is always available
1549 and it is always able to disable hot keys. Very old
1550 thinkpads are properly supported. hotkey_bios_mask
1551 is deprecated and marked for removal.
1553 0x020600: Marker for backlight change event support.
1555 0x020700: Support for mute-only mixers.
1556 Volume control in read-only mode by default.
1557 Marker for ALSA mixer support.
1559 0x030000: Thermal and fan sysfs attributes were moved to the hwmon
1560 device instead of being attached to the backing platform
1562 ========= ===============================================================
git.samba.org / sfrench / cifs-2.6.git / blob