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1 ThinkPad ACPI Extras Driver
3 Version 0.25
4 October 16th, 2013
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
24 issues.
26 "tpacpi" is used as a shorthand where "thinkpad-acpi" would be too
27 long due to length limitations on some Linux kernel versions.
29 Status
30 ------
32 The features currently supported are the following (see below for
33 detailed description):
35 - Fn key combinations
36 - Bluetooth enable and disable
37 - video output switching, expansion control
38 - ThinkLight on and off
39 - CMOS/UCMS control
40 - LED control
41 - ACPI sounds
42 - temperature sensors
43 - Experimental: embedded controller register dump
44 - LCD brightness control
45 - Volume control
46 - Fan control and monitoring: fan speed, fan enable/disable
47 - WAN enable and disable
48 - UWB enable and disable
50 A compatibility table by model and feature is maintained on the web
51 site, http://ibm-acpi.sf.net/. I appreciate any success or failure
52 reports, especially if they add to or correct the compatibility table.
53 Please include the following information in your report:
55 - ThinkPad model name
56 - a copy of your ACPI tables, using the "acpidump" utility
57 - a copy of the output of dmidecode, with serial numbers
58 and UUIDs masked off
59 - which driver features work and which don't
60 - the observed behavior of non-working features
62 Any other comments or patches are also more than welcome.
65 Installation
66 ------------
68 If you are compiling this driver as included in the Linux kernel
69 sources, look for the CONFIG_THINKPAD_ACPI Kconfig option.
70 It is located on the menu path: "Device Drivers" -> "X86 Platform
71 Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras".
74 Features
75 --------
77 The driver exports two different interfaces to userspace, which can be
78 used to access the features it provides. One is a legacy procfs-based
79 interface, which will be removed at some time in the future. The other
80 is a new sysfs-based interface which is not complete yet.
82 The procfs interface creates the /proc/acpi/ibm directory. There is a
83 file under that directory for each feature it supports. The procfs
84 interface is mostly frozen, and will change very little if at all: it
85 will not be extended to add any new functionality in the driver, instead
86 all new functionality will be implemented on the sysfs interface.
88 The sysfs interface tries to blend in the generic Linux sysfs subsystems
89 and classes as much as possible. Since some of these subsystems are not
90 yet ready or stabilized, it is expected that this interface will change,
91 and any and all userspace programs must deal with it.
94 Notes about the sysfs interface:
96 Unlike what was done with the procfs interface, correctness when talking
97 to the sysfs interfaces will be enforced, as will correctness in the
98 thinkpad-acpi's implementation of sysfs interfaces.
100 Also, any bugs in the thinkpad-acpi sysfs driver code or in the
101 thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
102 maximum correctness, even if that means changing an interface in
103 non-compatible ways. As these interfaces mature both in the kernel and
104 in thinkpad-acpi, such changes should become quite rare.
106 Applications interfacing to the thinkpad-acpi sysfs interfaces must
107 follow all sysfs guidelines and correctly process all errors (the sysfs
108 interface makes extensive use of errors). File descriptors and open /
109 close operations to the sysfs inodes must also be properly implemented.
111 The version of thinkpad-acpi's sysfs interface is exported by the driver
112 as a driver attribute (see below).
114 Sysfs driver attributes are on the driver's sysfs attribute space,
115 for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and
116 /sys/bus/platform/drivers/thinkpad_hwmon/
118 Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
119 space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/.
121 Sysfs device attributes for the sensors and fan are on the
122 thinkpad_hwmon device's sysfs attribute space, but you should locate it
123 looking for a hwmon device with the name attribute of "thinkpad", or
124 better yet, through libsensors. For 4.14+ sysfs attributes were moved to the
125 hwmon device (/sys/bus/platform/devices/thinkpad_hwmon/hwmon/hwmon? or
126 /sys/class/hwmon/hwmon?).
128 Driver version
129 --------------
131 procfs: /proc/acpi/ibm/driver
132 sysfs driver attribute: version
134 The driver name and version. No commands can be written to this file.
137 Sysfs interface version
138 -----------------------
140 sysfs driver attribute: interface_version
142 Version of the thinkpad-acpi sysfs interface, as an unsigned long
143 (output in hex format: 0xAAAABBCC), where:
144 AAAA - major revision
145 BB - minor revision
146 CC - bugfix revision
148 The sysfs interface version changelog for the driver can be found at the
149 end of this document. Changes to the sysfs interface done by the kernel
150 subsystems are not documented here, nor are they tracked by this
151 attribute.
153 Changes to the thinkpad-acpi sysfs interface are only considered
154 non-experimental when they are submitted to Linux mainline, at which
155 point the changes in this interface are documented and interface_version
156 may be updated. If you are using any thinkpad-acpi features not yet
157 sent to mainline for merging, you do so on your own risk: these features
158 may disappear, or be implemented in a different and incompatible way by
159 the time they are merged in Linux mainline.
161 Changes that are backwards-compatible by nature (e.g. the addition of
162 attributes that do not change the way the other attributes work) do not
163 always warrant an update of interface_version. Therefore, one must
164 expect that an attribute might not be there, and deal with it properly
165 (an attribute not being there *is* a valid way to make it clear that a
166 feature is not available in sysfs).
169 Hot keys
170 --------
172 procfs: /proc/acpi/ibm/hotkey
173 sysfs device attribute: hotkey_*
175 In a ThinkPad, the ACPI HKEY handler is responsible for communicating
176 some important events and also keyboard hot key presses to the operating
177 system. Enabling the hotkey functionality of thinkpad-acpi signals the
178 firmware that such a driver is present, and modifies how the ThinkPad
179 firmware will behave in many situations.
181 The driver enables the HKEY ("hot key") event reporting automatically
182 when loaded, and disables it when it is removed.
184 The driver will report HKEY events in the following format:
186 ibm/hotkey HKEY 00000080 0000xxxx
188 Some of these events refer to hot key presses, but not all of them.
190 The driver will generate events over the input layer for hot keys and
191 radio switches, and over the ACPI netlink layer for other events. The
192 input layer support accepts the standard IOCTLs to remap the keycodes
193 assigned to each hot key.
195 The hot key bit mask allows some control over which hot keys generate
196 events. If a key is "masked" (bit set to 0 in the mask), the firmware
197 will handle it. If it is "unmasked", it signals the firmware that
198 thinkpad-acpi would prefer to handle it, if the firmware would be so
199 kind to allow it (and it often doesn't!).
201 Not all bits in the mask can be modified. Not all bits that can be
202 modified do anything. Not all hot keys can be individually controlled
203 by the mask. Some models do not support the mask at all. The behaviour
204 of the mask is, therefore, highly dependent on the ThinkPad model.
206 The driver will filter out any unmasked hotkeys, so even if the firmware
207 doesn't allow disabling an specific hotkey, the driver will not report
208 events for unmasked hotkeys.
210 Note that unmasking some keys prevents their default behavior. For
211 example, if Fn+F5 is unmasked, that key will no longer enable/disable
212 Bluetooth by itself in firmware.
214 Note also that not all Fn key combinations are supported through ACPI
215 depending on the ThinkPad model and firmware version. On those
216 ThinkPads, it is still possible to support some extra hotkeys by
217 polling the "CMOS NVRAM" at least 10 times per second. The driver
218 attempts to enables this functionality automatically when required.
220 procfs notes:
222 The following commands can be written to the /proc/acpi/ibm/hotkey file:
224 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
225 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
226 ... any other 8-hex-digit mask ...
227 echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask
229 The following commands have been deprecated and will cause the kernel
230 to log a warning:
232 echo enable > /proc/acpi/ibm/hotkey -- does nothing
233 echo disable > /proc/acpi/ibm/hotkey -- returns an error
235 The procfs interface does not support NVRAM polling control. So as to
236 maintain maximum bug-to-bug compatibility, it does not report any masks,
237 nor does it allow one to manipulate the hot key mask when the firmware
238 does not support masks at all, even if NVRAM polling is in use.
240 sysfs notes:
242 hotkey_bios_enabled:
243 DEPRECATED, WILL BE REMOVED SOON.
245 Returns 0.
247 hotkey_bios_mask:
248 DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE.
250 Returns the hot keys mask when thinkpad-acpi was loaded.
251 Upon module unload, the hot keys mask will be restored
252 to this value. This is always 0x80c, because those are
253 the hotkeys that were supported by ancient firmware
254 without mask support.
256 hotkey_enable:
257 DEPRECATED, WILL BE REMOVED SOON.
259 0: returns -EPERM
260 1: does nothing
262 hotkey_mask:
263 bit mask to enable reporting (and depending on
264 the firmware, ACPI event generation) for each hot key
265 (see above). Returns the current status of the hot keys
266 mask, and allows one to modify it.
268 hotkey_all_mask:
269 bit mask that should enable event reporting for all
270 supported hot keys, when echoed to hotkey_mask above.
271 Unless you know which events need to be handled
272 passively (because the firmware *will* handle them
273 anyway), do *not* use hotkey_all_mask. Use
274 hotkey_recommended_mask, instead. You have been warned.
276 hotkey_recommended_mask:
277 bit mask that should enable event reporting for all
278 supported hot keys, except those which are always
279 handled by the firmware anyway. Echo it to
280 hotkey_mask above, to use. This is the default mask
281 used by the driver.
283 hotkey_source_mask:
284 bit mask that selects which hot keys will the driver
285 poll the NVRAM for. This is auto-detected by the driver
286 based on the capabilities reported by the ACPI firmware,
287 but it can be overridden at runtime.
289 Hot keys whose bits are set in hotkey_source_mask are
290 polled for in NVRAM, and reported as hotkey events if
291 enabled in hotkey_mask. Only a few hot keys are
292 available through CMOS NVRAM polling.
294 Warning: when in NVRAM mode, the volume up/down/mute
295 keys are synthesized according to changes in the mixer,
296 which uses a single volume up or volume down hotkey
297 press to unmute, as per the ThinkPad volume mixer user
298 interface. When in ACPI event mode, volume up/down/mute
299 events are reported by the firmware and can behave
300 differently (and that behaviour changes with firmware
301 version -- not just with firmware models -- as well as
302 OSI(Linux) state).
304 hotkey_poll_freq:
305 frequency in Hz for hot key polling. It must be between
306 0 and 25 Hz. Polling is only carried out when strictly
307 needed.
309 Setting hotkey_poll_freq to zero disables polling, and
310 will cause hot key presses that require NVRAM polling
311 to never be reported.
313 Setting hotkey_poll_freq too low may cause repeated
314 pressings of the same hot key to be misreported as a
315 single key press, or to not even be detected at all.
316 The recommended polling frequency is 10Hz.
318 hotkey_radio_sw:
319 If the ThinkPad has a hardware radio switch, this
320 attribute will read 0 if the switch is in the "radios
321 disabled" position, and 1 if the switch is in the
322 "radios enabled" position.
324 This attribute has poll()/select() support.
326 hotkey_tablet_mode:
327 If the ThinkPad has tablet capabilities, this attribute
328 will read 0 if the ThinkPad is in normal mode, and
329 1 if the ThinkPad is in tablet mode.
331 This attribute has poll()/select() support.
333 wakeup_reason:
334 Set to 1 if the system is waking up because the user
335 requested a bay ejection. Set to 2 if the system is
336 waking up because the user requested the system to
337 undock. Set to zero for normal wake-ups or wake-ups
338 due to unknown reasons.
340 This attribute has poll()/select() support.
342 wakeup_hotunplug_complete:
343 Set to 1 if the system was waken up because of an
344 undock or bay ejection request, and that request
345 was successfully completed. At this point, it might
346 be useful to send the system back to sleep, at the
347 user's choice. Refer to HKEY events 0x4003 and
348 0x3003, below.
350 This attribute has poll()/select() support.
352 input layer notes:
354 A Hot key is mapped to a single input layer EV_KEY event, possibly
355 followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
356 code. An EV_SYN event will always be generated to mark the end of the
357 event block.
359 Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
360 used as a helper to remap keys, only. They are particularly useful when
361 remapping KEY_UNKNOWN keys.
363 The events are available in an input device, with the following id:
365 Bus: BUS_HOST
366 vendor: 0x1014 (PCI_VENDOR_ID_IBM) or
367 0x17aa (PCI_VENDOR_ID_LENOVO)
368 product: 0x5054 ("TP")
369 version: 0x4101
371 The version will have its LSB incremented if the keymap changes in a
372 backwards-compatible way. The MSB shall always be 0x41 for this input
373 device. If the MSB is not 0x41, do not use the device as described in
374 this section, as it is either something else (e.g. another input device
375 exported by a thinkpad driver, such as HDAPS) or its functionality has
376 been changed in a non-backwards compatible way.
378 Adding other event types for other functionalities shall be considered a
379 backwards-compatible change for this input device.
381 Thinkpad-acpi Hot Key event map (version 0x4101):
383 ACPI Scan
384 event code Key Notes
386 0x1001 0x00 FN+F1 -
388 0x1002 0x01 FN+F2 IBM: battery (rare)
389 Lenovo: Screen lock
391 0x1003 0x02 FN+F3 Many IBM models always report
392 this hot key, even with hot keys
393 disabled or with Fn+F3 masked
394 off
395 IBM: screen lock, often turns
396 off the ThinkLight as side-effect
397 Lenovo: battery
399 0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
400 semantics, i.e. sleep-to-RAM).
401 It always generates some kind
402 of event, either the hot key
403 event or an ACPI sleep button
404 event. The firmware may
405 refuse to generate further FN+F4
406 key presses until a S3 or S4 ACPI
407 sleep cycle is performed or some
408 time passes.
410 0x1005 0x04 FN+F5 Radio. Enables/disables
411 the internal Bluetooth hardware
412 and W-WAN card if left in control
413 of the firmware. Does not affect
414 the WLAN card.
415 Should be used to turn on/off all
416 radios (Bluetooth+W-WAN+WLAN),
417 really.
419 0x1006 0x05 FN+F6 -
421 0x1007 0x06 FN+F7 Video output cycle.
422 Do you feel lucky today?
424 0x1008 0x07 FN+F8 IBM: toggle screen expand
425 Lenovo: configure UltraNav,
426 or toggle screen expand
428 0x1009 0x08 FN+F9 -
429 .. .. ..
430 0x100B 0x0A FN+F11 -
432 0x100C 0x0B FN+F12 Sleep to disk. You are always
433 supposed to handle it yourself,
434 either through the ACPI event,
435 or through a hotkey event.
436 The firmware may refuse to
437 generate further FN+F12 key
438 press events until a S3 or S4
439 ACPI sleep cycle is performed,
440 or some time passes.
442 0x100D 0x0C FN+BACKSPACE -
443 0x100E 0x0D FN+INSERT -
444 0x100F 0x0E FN+DELETE -
446 0x1010 0x0F FN+HOME Brightness up. This key is
447 always handled by the firmware
448 in IBM ThinkPads, even when
449 unmasked. Just leave it alone.
450 For Lenovo ThinkPads with a new
451 BIOS, it has to be handled either
452 by the ACPI OSI, or by userspace.
453 The driver does the right thing,
454 never mess with this.
455 0x1011 0x10 FN+END Brightness down. See brightness
456 up for details.
458 0x1012 0x11 FN+PGUP ThinkLight toggle. This key is
459 always handled by the firmware,
460 even when unmasked.
462 0x1013 0x12 FN+PGDOWN -
464 0x1014 0x13 FN+SPACE Zoom key
466 0x1015 0x14 VOLUME UP Internal mixer volume up. This
467 key is always handled by the
468 firmware, even when unmasked.
469 NOTE: Lenovo seems to be changing
470 this.
471 0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
472 key is always handled by the
473 firmware, even when unmasked.
474 NOTE: Lenovo seems to be changing
475 this.
476 0x1017 0x16 MUTE Mute internal mixer. This
477 key is always handled by the
478 firmware, even when unmasked.
480 0x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key
482 0x1019 0x18 unknown
483 .. .. ..
484 0x1020 0x1F unknown
486 The ThinkPad firmware does not allow one to differentiate when most hot
487 keys are pressed or released (either that, or we don't know how to, yet).
488 For these keys, the driver generates a set of events for a key press and
489 immediately issues the same set of events for a key release. It is
490 unknown by the driver if the ThinkPad firmware triggered these events on
491 hot key press or release, but the firmware will do it for either one, not
492 both.
494 If a key is mapped to KEY_RESERVED, it generates no input events at all.
495 If a key is mapped to KEY_UNKNOWN, it generates an input event that
496 includes an scan code. If a key is mapped to anything else, it will
497 generate input device EV_KEY events.
499 In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
500 events for switches:
502 SW_RFKILL_ALL T60 and later hardware rfkill rocker switch
503 SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
505 Non hotkey ACPI HKEY event map:
506 -------------------------------
508 Events that are never propagated by the driver:
510 0x2304 System is waking up from suspend to undock
511 0x2305 System is waking up from suspend to eject bay
512 0x2404 System is waking up from hibernation to undock
513 0x2405 System is waking up from hibernation to eject bay
514 0x5001 Lid closed
515 0x5002 Lid opened
516 0x5009 Tablet swivel: switched to tablet mode
517 0x500A Tablet swivel: switched to normal mode
518 0x5010 Brightness level changed/control event
519 0x6000 KEYBOARD: Numlock key pressed
520 0x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED)
521 0x7000 Radio Switch may have changed state
524 Events that are propagated by the driver to userspace:
526 0x2313 ALARM: System is waking up from suspend because
527 the battery is nearly empty
528 0x2413 ALARM: System is waking up from hibernation because
529 the battery is nearly empty
530 0x3003 Bay ejection (see 0x2x05) complete, can sleep again
531 0x3006 Bay hotplug request (hint to power up SATA link when
532 the optical drive tray is ejected)
533 0x4003 Undocked (see 0x2x04), can sleep again
534 0x4010 Docked into hotplug port replicator (non-ACPI dock)
535 0x4011 Undocked from hotplug port replicator (non-ACPI dock)
536 0x500B Tablet pen inserted into its storage bay
537 0x500C Tablet pen removed from its storage bay
538 0x6011 ALARM: battery is too hot
539 0x6012 ALARM: battery is extremely hot
540 0x6021 ALARM: a sensor is too hot
541 0x6022 ALARM: a sensor is extremely hot
542 0x6030 System thermal table changed
543 0x6032 Thermal Control command set completion (DYTC, Windows)
544 0x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED)
545 0x60C0 X1 Yoga 2016, Tablet mode status changed
546 0x60F0 Thermal Transformation changed (GMTS, Windows)
548 Battery nearly empty alarms are a last resort attempt to get the
549 operating system to hibernate or shutdown cleanly (0x2313), or shutdown
550 cleanly (0x2413) before power is lost. They must be acted upon, as the
551 wake up caused by the firmware will have negated most safety nets...
553 When any of the "too hot" alarms happen, according to Lenovo the user
554 should suspend or hibernate the laptop (and in the case of battery
555 alarms, unplug the AC adapter) to let it cool down. These alarms do
556 signal that something is wrong, they should never happen on normal
557 operating conditions.
559 The "extremely hot" alarms are emergencies. According to Lenovo, the
560 operating system is to force either an immediate suspend or hibernate
561 cycle, or a system shutdown. Obviously, something is very wrong if this
562 happens.
565 Brightness hotkey notes:
567 Don't mess with the brightness hotkeys in a Thinkpad. If you want
568 notifications for OSD, use the sysfs backlight class event support.
570 The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
571 automatically for the cases were userspace has to do something to
572 implement brightness changes. When you override these events, you will
573 either fail to handle properly the ThinkPads that require explicit
574 action to change backlight brightness, or the ThinkPads that require
575 that no action be taken to work properly.
578 Bluetooth
579 ---------
581 procfs: /proc/acpi/ibm/bluetooth
582 sysfs device attribute: bluetooth_enable (deprecated)
583 sysfs rfkill class: switch "tpacpi_bluetooth_sw"
585 This feature shows the presence and current state of a ThinkPad
586 Bluetooth device in the internal ThinkPad CDC slot.
588 If the ThinkPad supports it, the Bluetooth state is stored in NVRAM,
589 so it is kept across reboots and power-off.
591 Procfs notes:
593 If Bluetooth is installed, the following commands can be used:
595 echo enable > /proc/acpi/ibm/bluetooth
596 echo disable > /proc/acpi/ibm/bluetooth
598 Sysfs notes:
600 If the Bluetooth CDC card is installed, it can be enabled /
601 disabled through the "bluetooth_enable" thinkpad-acpi device
602 attribute, and its current status can also be queried.
604 enable:
605 0: disables Bluetooth / Bluetooth is disabled
606 1: enables Bluetooth / Bluetooth is enabled.
608 Note: this interface has been superseded by the generic rfkill
609 class. It has been deprecated, and it will be removed in year
610 2010.
612 rfkill controller switch "tpacpi_bluetooth_sw": refer to
613 Documentation/rfkill.txt for details.
616 Video output control -- /proc/acpi/ibm/video
617 --------------------------------------------
619 This feature allows control over the devices used for video output -
620 LCD, CRT or DVI (if available). The following commands are available:
622 echo lcd_enable > /proc/acpi/ibm/video
623 echo lcd_disable > /proc/acpi/ibm/video
624 echo crt_enable > /proc/acpi/ibm/video
625 echo crt_disable > /proc/acpi/ibm/video
626 echo dvi_enable > /proc/acpi/ibm/video
627 echo dvi_disable > /proc/acpi/ibm/video
628 echo auto_enable > /proc/acpi/ibm/video
629 echo auto_disable > /proc/acpi/ibm/video
630 echo expand_toggle > /proc/acpi/ibm/video
631 echo video_switch > /proc/acpi/ibm/video
633 NOTE: Access to this feature is restricted to processes owning the
634 CAP_SYS_ADMIN capability for safety reasons, as it can interact badly
635 enough with some versions of X.org to crash it.
637 Each video output device can be enabled or disabled individually.
638 Reading /proc/acpi/ibm/video shows the status of each device.
640 Automatic video switching can be enabled or disabled. When automatic
641 video switching is enabled, certain events (e.g. opening the lid,
642 docking or undocking) cause the video output device to change
643 automatically. While this can be useful, it also causes flickering
644 and, on the X40, video corruption. By disabling automatic switching,
645 the flickering or video corruption can be avoided.
647 The video_switch command cycles through the available video outputs
648 (it simulates the behavior of Fn-F7).
650 Video expansion can be toggled through this feature. This controls
651 whether the display is expanded to fill the entire LCD screen when a
652 mode with less than full resolution is used. Note that the current
653 video expansion status cannot be determined through this feature.
655 Note that on many models (particularly those using Radeon graphics
656 chips) the X driver configures the video card in a way which prevents
657 Fn-F7 from working. This also disables the video output switching
658 features of this driver, as it uses the same ACPI methods as
659 Fn-F7. Video switching on the console should still work.
661 UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000
664 ThinkLight control
665 ------------------
667 procfs: /proc/acpi/ibm/light
668 sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
670 procfs notes:
672 The ThinkLight status can be read and set through the procfs interface. A
673 few models which do not make the status available will show the ThinkLight
674 status as "unknown". The available commands are:
676 echo on > /proc/acpi/ibm/light
677 echo off > /proc/acpi/ibm/light
679 sysfs notes:
681 The ThinkLight sysfs interface is documented by the LED class
682 documentation, in Documentation/leds/leds-class.txt. The ThinkLight LED name
683 is "tpacpi::thinklight".
685 Due to limitations in the sysfs LED class, if the status of the ThinkLight
686 cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
687 It is impossible to know if the status returned through sysfs is valid.
690 CMOS/UCMS control
691 -----------------
693 procfs: /proc/acpi/ibm/cmos
694 sysfs device attribute: cmos_command
696 This feature is mostly used internally by the ACPI firmware to keep the legacy
697 CMOS NVRAM bits in sync with the current machine state, and to record this
698 state so that the ThinkPad will retain such settings across reboots.
700 Some of these commands actually perform actions in some ThinkPad models, but
701 this is expected to disappear more and more in newer models. As an example, in
702 a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
703 real, but commands 0 to 2 don't control the mixer anymore (they have been
704 phased out) and just update the NVRAM.
706 The range of valid cmos command numbers is 0 to 21, but not all have an
707 effect and the behavior varies from model to model. Here is the behavior
708 on the X40 (tpb is the ThinkPad Buttons utility):
710 0 - Related to "Volume down" key press
711 1 - Related to "Volume up" key press
712 2 - Related to "Mute on" key press
713 3 - Related to "Access IBM" key press
714 4 - Related to "LCD brightness up" key press
715 5 - Related to "LCD brightness down" key press
716 11 - Related to "toggle screen expansion" key press/function
717 12 - Related to "ThinkLight on"
718 13 - Related to "ThinkLight off"
719 14 - Related to "ThinkLight" key press (toggle ThinkLight)
721 The cmos command interface is prone to firmware split-brain problems, as
722 in newer ThinkPads it is just a compatibility layer. Do not use it, it is
723 exported just as a debug tool.
726 LED control
727 -----------
729 procfs: /proc/acpi/ibm/led
730 sysfs attributes: as per LED class, see below for names
732 Some of the LED indicators can be controlled through this feature. On
733 some older ThinkPad models, it is possible to query the status of the
734 LED indicators as well. Newer ThinkPads cannot query the real status
735 of the LED indicators.
737 Because misuse of the LEDs could induce an unaware user to perform
738 dangerous actions (like undocking or ejecting a bay device while the
739 buses are still active), or mask an important alarm (such as a nearly
740 empty battery, or a broken battery), access to most LEDs is
741 restricted.
743 Unrestricted access to all LEDs requires that thinkpad-acpi be
744 compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled.
745 Distributions must never enable this option. Individual users that
746 are aware of the consequences are welcome to enabling it.
748 Audio mute and microphone mute LEDs are supported, but currently not
749 visible to userspace. They are used by the snd-hda-intel audio driver.
751 procfs notes:
753 The available commands are:
755 echo '<LED number> on' >/proc/acpi/ibm/led
756 echo '<LED number> off' >/proc/acpi/ibm/led
757 echo '<LED number> blink' >/proc/acpi/ibm/led
759 The <LED number> range is 0 to 15. The set of LEDs that can be
760 controlled varies from model to model. Here is the common ThinkPad
761 mapping:
763 0 - power
764 1 - battery (orange)
765 2 - battery (green)
766 3 - UltraBase/dock
767 4 - UltraBay
768 5 - UltraBase battery slot
769 6 - (unknown)
770 7 - standby
771 8 - dock status 1
772 9 - dock status 2
773 10, 11 - (unknown)
774 12 - thinkvantage
775 13, 14, 15 - (unknown)
777 All of the above can be turned on and off and can be made to blink.
779 sysfs notes:
781 The ThinkPad LED sysfs interface is described in detail by the LED class
782 documentation, in Documentation/leds/leds-class.txt.
784 The LEDs are named (in LED ID order, from 0 to 12):
785 "tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
786 "tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
787 "tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1",
788 "tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3",
789 "tpacpi::thinkvantage".
791 Due to limitations in the sysfs LED class, if the status of the LED
792 indicators cannot be read due to an error, thinkpad-acpi will report it as
793 a brightness of zero (same as LED off).
795 If the thinkpad firmware doesn't support reading the current status,
796 trying to read the current LED brightness will just return whatever
797 brightness was last written to that attribute.
799 These LEDs can blink using hardware acceleration. To request that a
800 ThinkPad indicator LED should blink in hardware accelerated mode, use the
801 "timer" trigger, and leave the delay_on and delay_off parameters set to
802 zero (to request hardware acceleration autodetection).
804 LEDs that are known not to exist in a given ThinkPad model are not
805 made available through the sysfs interface. If you have a dock and you
806 notice there are LEDs listed for your ThinkPad that do not exist (and
807 are not in the dock), or if you notice that there are missing LEDs,
808 a report to ibm-acpi-devel@lists.sourceforge.net is appreciated.
811 ACPI sounds -- /proc/acpi/ibm/beep
812 ----------------------------------
814 The BEEP method is used internally by the ACPI firmware to provide
815 audible alerts in various situations. This feature allows the same
816 sounds to be triggered manually.
818 The commands are non-negative integer numbers:
820 echo <number> >/proc/acpi/ibm/beep
822 The valid <number> range is 0 to 17. Not all numbers trigger sounds
823 and the sounds vary from model to model. Here is the behavior on the
824 X40:
826 0 - stop a sound in progress (but use 17 to stop 16)
827 2 - two beeps, pause, third beep ("low battery")
828 3 - single beep
829 4 - high, followed by low-pitched beep ("unable")
830 5 - single beep
831 6 - very high, followed by high-pitched beep ("AC/DC")
832 7 - high-pitched beep
833 9 - three short beeps
834 10 - very long beep
835 12 - low-pitched beep
836 15 - three high-pitched beeps repeating constantly, stop with 0
837 16 - one medium-pitched beep repeating constantly, stop with 17
838 17 - stop 16
841 Temperature sensors
842 -------------------
844 procfs: /proc/acpi/ibm/thermal
845 sysfs device attributes: (hwmon "thinkpad") temp*_input
847 Most ThinkPads include six or more separate temperature sensors but only
848 expose the CPU temperature through the standard ACPI methods. This
849 feature shows readings from up to eight different sensors on older
850 ThinkPads, and up to sixteen different sensors on newer ThinkPads.
852 For example, on the X40, a typical output may be:
853 temperatures: 42 42 45 41 36 -128 33 -128
855 On the T43/p, a typical output may be:
856 temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
858 The mapping of thermal sensors to physical locations varies depending on
859 system-board model (and thus, on ThinkPad model).
861 http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
862 tries to track down these locations for various models.
864 Most (newer?) models seem to follow this pattern:
866 1: CPU
867 2: (depends on model)
868 3: (depends on model)
869 4: GPU
870 5: Main battery: main sensor
871 6: Bay battery: main sensor
872 7: Main battery: secondary sensor
873 8: Bay battery: secondary sensor
874 9-15: (depends on model)
876 For the R51 (source: Thomas Gruber):
877 2: Mini-PCI
878 3: Internal HDD
880 For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
881 http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
882 2: System board, left side (near PCMCIA slot), reported as HDAPS temp
883 3: PCMCIA slot
884 9: MCH (northbridge) to DRAM Bus
885 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
886 card, under touchpad
887 11: Power regulator, underside of system board, below F2 key
889 The A31 has a very atypical layout for the thermal sensors
890 (source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
891 1: CPU
892 2: Main Battery: main sensor
893 3: Power Converter
894 4: Bay Battery: main sensor
895 5: MCH (northbridge)
896 6: PCMCIA/ambient
897 7: Main Battery: secondary sensor
898 8: Bay Battery: secondary sensor
901 Procfs notes:
902 Readings from sensors that are not available return -128.
903 No commands can be written to this file.
905 Sysfs notes:
906 Sensors that are not available return the ENXIO error. This
907 status may change at runtime, as there are hotplug thermal
908 sensors, like those inside the batteries and docks.
910 thinkpad-acpi thermal sensors are reported through the hwmon
911 subsystem, and follow all of the hwmon guidelines at
912 Documentation/hwmon.
914 EXPERIMENTAL: Embedded controller register dump
915 -----------------------------------------------
917 This feature is not included in the thinkpad driver anymore.
918 Instead the EC can be accessed through /sys/kernel/debug/ec with
919 a userspace tool which can be found here:
920 ftp://ftp.suse.com/pub/people/trenn/sources/ec
922 Use it to determine the register holding the fan
923 speed on some models. To do that, do the following:
924 - make sure the battery is fully charged
925 - make sure the fan is running
926 - use above mentioned tool to read out the EC
928 Often fan and temperature values vary between
929 readings. Since temperatures don't change vary fast, you can take
930 several quick dumps to eliminate them.
932 You can use a similar method to figure out the meaning of other
933 embedded controller registers - e.g. make sure nothing else changes
934 except the charging or discharging battery to determine which
935 registers contain the current battery capacity, etc. If you experiment
936 with this, do send me your results (including some complete dumps with
937 a description of the conditions when they were taken.)
940 LCD brightness control
941 ----------------------
943 procfs: /proc/acpi/ibm/brightness
944 sysfs backlight device "thinkpad_screen"
946 This feature allows software control of the LCD brightness on ThinkPad
947 models which don't have a hardware brightness slider.
949 It has some limitations: the LCD backlight cannot be actually turned
950 on or off by this interface, it just controls the backlight brightness
951 level.
953 On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
954 has eight brightness levels, ranging from 0 to 7. Some of the levels
955 may not be distinct. Later Lenovo models that implement the ACPI
956 display backlight brightness control methods have 16 levels, ranging
957 from 0 to 15.
959 For IBM ThinkPads, there are two interfaces to the firmware for direct
960 brightness control, EC and UCMS (or CMOS). To select which one should be
961 used, use the brightness_mode module parameter: brightness_mode=1 selects
962 EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC
963 mode with NVRAM backing (so that brightness changes are remembered across
964 shutdown/reboot).
966 The driver tries to select which interface to use from a table of
967 defaults for each ThinkPad model. If it makes a wrong choice, please
968 report this as a bug, so that we can fix it.
970 Lenovo ThinkPads only support brightness_mode=2 (UCMS).
972 When display backlight brightness controls are available through the
973 standard ACPI interface, it is best to use it instead of this direct
974 ThinkPad-specific interface. The driver will disable its native
975 backlight brightness control interface if it detects that the standard
976 ACPI interface is available in the ThinkPad.
978 If you want to use the thinkpad-acpi backlight brightness control
979 instead of the generic ACPI video backlight brightness control for some
980 reason, you should use the acpi_backlight=vendor kernel parameter.
982 The brightness_enable module parameter can be used to control whether
983 the LCD brightness control feature will be enabled when available.
984 brightness_enable=0 forces it to be disabled. brightness_enable=1
985 forces it to be enabled when available, even if the standard ACPI
986 interface is also available.
988 Procfs notes:
990 The available commands are:
992 echo up >/proc/acpi/ibm/brightness
993 echo down >/proc/acpi/ibm/brightness
994 echo 'level <level>' >/proc/acpi/ibm/brightness
996 Sysfs notes:
998 The interface is implemented through the backlight sysfs class, which is
999 poorly documented at this time.
1001 Locate the thinkpad_screen device under /sys/class/backlight, and inside
1002 it there will be the following attributes:
1004 max_brightness:
1005 Reads the maximum brightness the hardware can be set to.
1006 The minimum is always zero.
1008 actual_brightness:
1009 Reads what brightness the screen is set to at this instant.
1011 brightness:
1012 Writes request the driver to change brightness to the
1013 given value. Reads will tell you what brightness the
1014 driver is trying to set the display to when "power" is set
1015 to zero and the display has not been dimmed by a kernel
1016 power management event.
1018 power:
1019 power management mode, where 0 is "display on", and 1 to 3
1020 will dim the display backlight to brightness level 0
1021 because thinkpad-acpi cannot really turn the backlight
1022 off. Kernel power management events can temporarily
1023 increase the current power management level, i.e. they can
1024 dim the display.
1027 WARNING:
1029 Whatever you do, do NOT ever call thinkpad-acpi backlight-level change
1030 interface and the ACPI-based backlight level change interface
1031 (available on newer BIOSes, and driven by the Linux ACPI video driver)
1032 at the same time. The two will interact in bad ways, do funny things,
1033 and maybe reduce the life of the backlight lamps by needlessly kicking
1034 its level up and down at every change.
1037 Volume control (Console Audio control)
1038 --------------------------------------
1040 procfs: /proc/acpi/ibm/volume
1041 ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC"
1043 NOTE: by default, the volume control interface operates in read-only
1044 mode, as it is supposed to be used for on-screen-display purposes.
1045 The read/write mode can be enabled through the use of the
1046 "volume_control=1" module parameter.
1048 NOTE: distros are urged to not enable volume_control by default, this
1049 should be done by the local admin only. The ThinkPad UI is for the
1050 console audio control to be done through the volume keys only, and for
1051 the desktop environment to just provide on-screen-display feedback.
1052 Software volume control should be done only in the main AC97/HDA
1053 mixer.
1056 About the ThinkPad Console Audio control:
1058 ThinkPads have a built-in amplifier and muting circuit that drives the
1059 console headphone and speakers. This circuit is after the main AC97
1060 or HDA mixer in the audio path, and under exclusive control of the
1061 firmware.
1063 ThinkPads have three special hotkeys to interact with the console
1064 audio control: volume up, volume down and mute.
1066 It is worth noting that the normal way the mute function works (on
1067 ThinkPads that do not have a "mute LED") is:
1069 1. Press mute to mute. It will *always* mute, you can press it as
1070 many times as you want, and the sound will remain mute.
1072 2. Press either volume key to unmute the ThinkPad (it will _not_
1073 change the volume, it will just unmute).
1075 This is a very superior design when compared to the cheap software-only
1076 mute-toggle solution found on normal consumer laptops: you can be
1077 absolutely sure the ThinkPad will not make noise if you press the mute
1078 button, no matter the previous state.
1080 The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain
1081 amplifiers driving the speakers and headphone output, and the firmware
1082 also handles volume control for the headphone and speakers on these
1083 ThinkPads without any help from the operating system (this volume
1084 control stage exists after the main AC97 or HDA mixer in the audio
1085 path).
1087 The newer Lenovo models only have firmware mute control, and depend on
1088 the main HDA mixer to do volume control (which is done by the operating
1089 system). In this case, the volume keys are filtered out for unmute
1090 key press (there are some firmware bugs in this area) and delivered as
1091 normal key presses to the operating system (thinkpad-acpi is not
1092 involved).
1095 The ThinkPad-ACPI volume control:
1097 The preferred way to interact with the Console Audio control is the
1098 ALSA interface.
1100 The legacy procfs interface allows one to read the current state,
1101 and if volume control is enabled, accepts the following commands:
1103 echo up >/proc/acpi/ibm/volume
1104 echo down >/proc/acpi/ibm/volume
1105 echo mute >/proc/acpi/ibm/volume
1106 echo unmute >/proc/acpi/ibm/volume
1107 echo 'level <level>' >/proc/acpi/ibm/volume
1109 The <level> number range is 0 to 14 although not all of them may be
1110 distinct. To unmute the volume after the mute command, use either the
1111 up or down command (the level command will not unmute the volume), or
1112 the unmute command.
1114 You can use the volume_capabilities parameter to tell the driver
1115 whether your thinkpad has volume control or mute-only control:
1116 volume_capabilities=1 for mixers with mute and volume control,
1117 volume_capabilities=2 for mixers with only mute control.
1119 If the driver misdetects the capabilities for your ThinkPad model,
1120 please report this to ibm-acpi-devel@lists.sourceforge.net, so that we
1121 can update the driver.
1123 There are two strategies for volume control. To select which one
1124 should be used, use the volume_mode module parameter: volume_mode=1
1125 selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing
1126 (so that volume/mute changes are remembered across shutdown/reboot).
1128 The driver will operate in volume_mode=3 by default. If that does not
1129 work well on your ThinkPad model, please report this to
1130 ibm-acpi-devel@lists.sourceforge.net.
1132 The driver supports the standard ALSA module parameters. If the ALSA
1133 mixer is disabled, the driver will disable all volume functionality.
1136 Fan control and monitoring: fan speed, fan enable/disable
1137 ---------------------------------------------------------
1139 procfs: /proc/acpi/ibm/fan
1140 sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
1141 pwm1_enable, fan2_input
1142 sysfs hwmon driver attributes: fan_watchdog
1144 NOTE NOTE NOTE: fan control operations are disabled by default for
1145 safety reasons. To enable them, the module parameter "fan_control=1"
1146 must be given to thinkpad-acpi.
1148 This feature attempts to show the current fan speed, control mode and
1149 other fan data that might be available. The speed is read directly
1150 from the hardware registers of the embedded controller. This is known
1151 to work on later R, T, X and Z series ThinkPads but may show a bogus
1152 value on other models.
1154 Some Lenovo ThinkPads support a secondary fan. This fan cannot be
1155 controlled separately, it shares the main fan control.
1157 Fan levels:
1159 Most ThinkPad fans work in "levels" at the firmware interface. Level 0
1160 stops the fan. The higher the level, the higher the fan speed, although
1161 adjacent levels often map to the same fan speed. 7 is the highest
1162 level, where the fan reaches the maximum recommended speed.
1164 Level "auto" means the EC changes the fan level according to some
1165 internal algorithm, usually based on readings from the thermal sensors.
1167 There is also a "full-speed" level, also known as "disengaged" level.
1168 In this level, the EC disables the speed-locked closed-loop fan control,
1169 and drives the fan as fast as it can go, which might exceed hardware
1170 limits, so use this level with caution.
1172 The fan usually ramps up or down slowly from one speed to another, and
1173 it is normal for the EC to take several seconds to react to fan
1174 commands. The full-speed level may take up to two minutes to ramp up to
1175 maximum speed, and in some ThinkPads, the tachometer readings go stale
1176 while the EC is transitioning to the full-speed level.
1178 WARNING WARNING WARNING: do not leave the fan disabled unless you are
1179 monitoring all of the temperature sensor readings and you are ready to
1180 enable it if necessary to avoid overheating.
1182 An enabled fan in level "auto" may stop spinning if the EC decides the
1183 ThinkPad is cool enough and doesn't need the extra airflow. This is
1184 normal, and the EC will spin the fan up if the various thermal readings
1185 rise too much.
1187 On the X40, this seems to depend on the CPU and HDD temperatures.
1188 Specifically, the fan is turned on when either the CPU temperature
1189 climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
1190 fan is turned off when the CPU temperature drops to 49 degrees and the
1191 HDD temperature drops to 41 degrees. These thresholds cannot
1192 currently be controlled.
1194 The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
1195 certain conditions are met. It will override any fan programming done
1196 through thinkpad-acpi.
1198 The thinkpad-acpi kernel driver can be programmed to revert the fan
1199 level to a safe setting if userspace does not issue one of the procfs
1200 fan commands: "enable", "disable", "level" or "watchdog", or if there
1201 are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
1202 set to 1, manual mode) within a configurable amount of time of up to
1203 120 seconds. This functionality is called fan safety watchdog.
1205 Note that the watchdog timer stops after it enables the fan. It will be
1206 rearmed again automatically (using the same interval) when one of the
1207 above mentioned fan commands is received. The fan watchdog is,
1208 therefore, not suitable to protect against fan mode changes made through
1209 means other than the "enable", "disable", and "level" procfs fan
1210 commands, or the hwmon fan control sysfs interface.
1212 Procfs notes:
1214 The fan may be enabled or disabled with the following commands:
1216 echo enable >/proc/acpi/ibm/fan
1217 echo disable >/proc/acpi/ibm/fan
1219 Placing a fan on level 0 is the same as disabling it. Enabling a fan
1220 will try to place it in a safe level if it is too slow or disabled.
1222 The fan level can be controlled with the command:
1224 echo 'level <level>' > /proc/acpi/ibm/fan
1226 Where <level> is an integer from 0 to 7, or one of the words "auto" or
1227 "full-speed" (without the quotes). Not all ThinkPads support the "auto"
1228 and "full-speed" levels. The driver accepts "disengaged" as an alias for
1229 "full-speed", and reports it as "disengaged" for backwards
1230 compatibility.
1232 On the X31 and X40 (and ONLY on those models), the fan speed can be
1233 controlled to a certain degree. Once the fan is running, it can be
1234 forced to run faster or slower with the following command:
1236 echo 'speed <speed>' > /proc/acpi/ibm/fan
1238 The sustainable range of fan speeds on the X40 appears to be from about
1239 3700 to about 7350. Values outside this range either do not have any
1240 effect or the fan speed eventually settles somewhere in that range. The
1241 fan cannot be stopped or started with this command. This functionality
1242 is incomplete, and not available through the sysfs interface.
1244 To program the safety watchdog, use the "watchdog" command.
1246 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
1248 If you want to disable the watchdog, use 0 as the interval.
1250 Sysfs notes:
1252 The sysfs interface follows the hwmon subsystem guidelines for the most
1253 part, and the exception is the fan safety watchdog.
1255 Writes to any of the sysfs attributes may return the EINVAL error if
1256 that operation is not supported in a given ThinkPad or if the parameter
1257 is out-of-bounds, and EPERM if it is forbidden. They may also return
1258 EINTR (interrupted system call), and EIO (I/O error while trying to talk
1259 to the firmware).
1261 Features not yet implemented by the driver return ENOSYS.
1263 hwmon device attribute pwm1_enable:
1264 0: PWM offline (fan is set to full-speed mode)
1265 1: Manual PWM control (use pwm1 to set fan level)
1266 2: Hardware PWM control (EC "auto" mode)
1267 3: reserved (Software PWM control, not implemented yet)
1269 Modes 0 and 2 are not supported by all ThinkPads, and the
1270 driver is not always able to detect this. If it does know a
1271 mode is unsupported, it will return -EINVAL.
1273 hwmon device attribute pwm1:
1274 Fan level, scaled from the firmware values of 0-7 to the hwmon
1275 scale of 0-255. 0 means fan stopped, 255 means highest normal
1276 speed (level 7).
1278 This attribute only commands the fan if pmw1_enable is set to 1
1279 (manual PWM control).
1281 hwmon device attribute fan1_input:
1282 Fan tachometer reading, in RPM. May go stale on certain
1283 ThinkPads while the EC transitions the PWM to offline mode,
1284 which can take up to two minutes. May return rubbish on older
1285 ThinkPads.
1287 hwmon device attribute fan2_input:
1288 Fan tachometer reading, in RPM, for the secondary fan.
1289 Available only on some ThinkPads. If the secondary fan is
1290 not installed, will always read 0.
1292 hwmon driver attribute fan_watchdog:
1293 Fan safety watchdog timer interval, in seconds. Minimum is
1294 1 second, maximum is 120 seconds. 0 disables the watchdog.
1296 To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
1298 To start the fan in a safe mode: set pwm1_enable to 2. If that fails
1299 with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
1300 would be the safest choice, though).
1303 WAN
1304 ---
1306 procfs: /proc/acpi/ibm/wan
1307 sysfs device attribute: wwan_enable (deprecated)
1308 sysfs rfkill class: switch "tpacpi_wwan_sw"
1310 This feature shows the presence and current state of the built-in
1311 Wireless WAN device.
1313 If the ThinkPad supports it, the WWAN state is stored in NVRAM,
1314 so it is kept across reboots and power-off.
1316 It was tested on a Lenovo ThinkPad X60. It should probably work on other
1317 ThinkPad models which come with this module installed.
1319 Procfs notes:
1321 If the W-WAN card is installed, the following commands can be used:
1323 echo enable > /proc/acpi/ibm/wan
1324 echo disable > /proc/acpi/ibm/wan
1326 Sysfs notes:
1328 If the W-WAN card is installed, it can be enabled /
1329 disabled through the "wwan_enable" thinkpad-acpi device
1330 attribute, and its current status can also be queried.
1332 enable:
1333 0: disables WWAN card / WWAN card is disabled
1334 1: enables WWAN card / WWAN card is enabled.
1336 Note: this interface has been superseded by the generic rfkill
1337 class. It has been deprecated, and it will be removed in year
1338 2010.
1340 rfkill controller switch "tpacpi_wwan_sw": refer to
1341 Documentation/rfkill.txt for details.
1344 EXPERIMENTAL: UWB
1345 -----------------
1347 This feature is considered EXPERIMENTAL because it has not been extensively
1348 tested and validated in various ThinkPad models yet. The feature may not
1349 work as expected. USE WITH CAUTION! To use this feature, you need to supply
1350 the experimental=1 parameter when loading the module.
1352 sysfs rfkill class: switch "tpacpi_uwb_sw"
1354 This feature exports an rfkill controller for the UWB device, if one is
1355 present and enabled in the BIOS.
1357 Sysfs notes:
1359 rfkill controller switch "tpacpi_uwb_sw": refer to
1360 Documentation/rfkill.txt for details.
1362 Adaptive keyboard
1363 -----------------
1365 sysfs device attribute: adaptive_kbd_mode
1367 This sysfs attribute controls the keyboard "face" that will be shown on the
1368 Lenovo X1 Carbon 2nd gen (2014)'s adaptive keyboard. The value can be read
1369 and set.
1371 1 = Home mode
1372 2 = Web-browser mode
1373 3 = Web-conference mode
1374 4 = Function mode
1375 5 = Layflat mode
1377 For more details about which buttons will appear depending on the mode, please
1378 review the laptop's user guide:
1379 http://www.lenovo.com/shop/americas/content/user_guides/x1carbon_2_ug_en.pdf
1381 Multiple Commands, Module Parameters
1382 ------------------------------------
1384 Multiple commands can be written to the proc files in one shot by
1385 separating them with commas, for example:
1387 echo enable,0xffff > /proc/acpi/ibm/hotkey
1388 echo lcd_disable,crt_enable > /proc/acpi/ibm/video
1390 Commands can also be specified when loading the thinkpad-acpi module,
1391 for example:
1393 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
1396 Enabling debugging output
1397 -------------------------
1399 The module takes a debug parameter which can be used to selectively
1400 enable various classes of debugging output, for example:
1402 modprobe thinkpad_acpi debug=0xffff
1404 will enable all debugging output classes. It takes a bitmask, so
1405 to enable more than one output class, just add their values.
1407 Debug bitmask Description
1408 0x8000 Disclose PID of userspace programs
1409 accessing some functions of the driver
1410 0x0001 Initialization and probing
1411 0x0002 Removal
1412 0x0004 RF Transmitter control (RFKILL)
1413 (bluetooth, WWAN, UWB...)
1414 0x0008 HKEY event interface, hotkeys
1415 0x0010 Fan control
1416 0x0020 Backlight brightness
1417 0x0040 Audio mixer/volume control
1419 There is also a kernel build option to enable more debugging
1420 information, which may be necessary to debug driver problems.
1422 The level of debugging information output by the driver can be changed
1423 at runtime through sysfs, using the driver attribute debug_level. The
1424 attribute takes the same bitmask as the debug module parameter above.
1427 Force loading of module
1428 -----------------------
1430 If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
1431 the module parameter force_load=1. Regardless of whether this works or
1432 not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
1435 Sysfs interface changelog:
1437 0x000100: Initial sysfs support, as a single platform driver and
1438 device.
1439 0x000200: Hot key support for 32 hot keys, and radio slider switch
1440 support.
1441 0x010000: Hot keys are now handled by default over the input
1442 layer, the radio switch generates input event EV_RADIO,
1443 and the driver enables hot key handling by default in
1444 the firmware.
1446 0x020000: ABI fix: added a separate hwmon platform device and
1447 driver, which must be located by name (thinkpad)
1448 and the hwmon class for libsensors4 (lm-sensors 3)
1449 compatibility. Moved all hwmon attributes to this
1450 new platform device.
1452 0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
1453 support. If you must, use it to know you should not
1454 start a userspace NVRAM poller (allows to detect when
1455 NVRAM is compiled out by the user because it is
1456 unneeded/undesired in the first place).
1457 0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
1458 and proper hotkey_mask semantics (version 8 of the
1459 NVRAM polling patch). Some development snapshots of
1460 0.18 had an earlier version that did strange things
1461 to hotkey_mask.
1463 0x020200: Add poll()/select() support to the following attributes:
1464 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason
1466 0x020300: hotkey enable/disable support removed, attributes
1467 hotkey_bios_enabled and hotkey_enable deprecated and
1468 marked for removal.
1470 0x020400: Marker for 16 LEDs support. Also, LEDs that are known
1471 to not exist in a given model are not registered with
1472 the LED sysfs class anymore.
1474 0x020500: Updated hotkey driver, hotkey_mask is always available
1475 and it is always able to disable hot keys. Very old
1476 thinkpads are properly supported. hotkey_bios_mask
1477 is deprecated and marked for removal.
1479 0x020600: Marker for backlight change event support.
1481 0x020700: Support for mute-only mixers.
1482 Volume control in read-only mode by default.
1483 Marker for ALSA mixer support.
1485 0x030000: Thermal and fan sysfs attributes were moved to the hwmon
1486 device instead of being attached to the backing platform
1487 device.