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1 ThinkPad ACPI Extras Driver
3 Version 0.18
4 October 08th, 2007
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.
22 Status
23 ------
25 The features currently supported are the following (see below for
26 detailed description):
28 - Fn key combinations
29 - Bluetooth enable and disable
30 - video output switching, expansion control
31 - ThinkLight on and off
32 - limited docking and undocking
33 - UltraBay eject
34 - CMOS control
35 - LED control
36 - ACPI sounds
37 - temperature sensors
38 - Experimental: embedded controller register dump
39 - LCD brightness control
40 - Volume control
41 - Fan control and monitoring: fan speed, fan enable/disable
42 - Experimental: WAN enable and disable
44 A compatibility table by model and feature is maintained on the web
45 site, http://ibm-acpi.sf.net/. I appreciate any success or failure
46 reports, especially if they add to or correct the compatibility table.
47 Please include the following information in your report:
49 - ThinkPad model name
50 - a copy of your DSDT, from /proc/acpi/dsdt
51 - a copy of the output of dmidecode, with serial numbers
52 and UUIDs masked off
53 - which driver features work and which don't
54 - the observed behavior of non-working features
56 Any other comments or patches are also more than welcome.
59 Installation
60 ------------
62 If you are compiling this driver as included in the Linux kernel
63 sources, simply enable the CONFIG_THINKPAD_ACPI option, and optionally
64 enable the CONFIG_THINKPAD_ACPI_BAY option if you want the
65 thinkpad-specific bay functionality.
67 Features
68 --------
70 The driver exports two different interfaces to userspace, which can be
71 used to access the features it provides. One is a legacy procfs-based
72 interface, which will be removed at some time in the distant future.
73 The other is a new sysfs-based interface which is not complete yet.
75 The procfs interface creates the /proc/acpi/ibm directory. There is a
76 file under that directory for each feature it supports. The procfs
77 interface is mostly frozen, and will change very little if at all: it
78 will not be extended to add any new functionality in the driver, instead
79 all new functionality will be implemented on the sysfs interface.
81 The sysfs interface tries to blend in the generic Linux sysfs subsystems
82 and classes as much as possible. Since some of these subsystems are not
83 yet ready or stabilized, it is expected that this interface will change,
84 and any and all userspace programs must deal with it.
87 Notes about the sysfs interface:
89 Unlike what was done with the procfs interface, correctness when talking
90 to the sysfs interfaces will be enforced, as will correctness in the
91 thinkpad-acpi's implementation of sysfs interfaces.
93 Also, any bugs in the thinkpad-acpi sysfs driver code or in the
94 thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
95 maximum correctness, even if that means changing an interface in
96 non-compatible ways. As these interfaces mature both in the kernel and
97 in thinkpad-acpi, such changes should become quite rare.
99 Applications interfacing to the thinkpad-acpi sysfs interfaces must
100 follow all sysfs guidelines and correctly process all errors (the sysfs
101 interface makes extensive use of errors). File descriptors and open /
102 close operations to the sysfs inodes must also be properly implemented.
104 The version of thinkpad-acpi's sysfs interface is exported by the driver
105 as a driver attribute (see below).
107 Sysfs driver attributes are on the driver's sysfs attribute space,
108 for 2.6.23 this is /sys/bus/platform/drivers/thinkpad_acpi/ and
109 /sys/bus/platform/drivers/thinkpad_hwmon/
111 Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
112 space, for 2.6.23 this is /sys/devices/platform/thinkpad_acpi/.
114 Sysfs device attributes for the sensors and fan are on the
115 thinkpad_hwmon device's sysfs attribute space, but you should locate it
116 looking for a hwmon device with the name attribute of "thinkpad".
118 Driver version
119 --------------
121 procfs: /proc/acpi/ibm/driver
122 sysfs driver attribute: version
124 The driver name and version. No commands can be written to this file.
126 Sysfs interface version
127 -----------------------
129 sysfs driver attribute: interface_version
131 Version of the thinkpad-acpi sysfs interface, as an unsigned long
132 (output in hex format: 0xAAAABBCC), where:
133 AAAA - major revision
134 BB - minor revision
135 CC - bugfix revision
137 The sysfs interface version changelog for the driver can be found at the
138 end of this document. Changes to the sysfs interface done by the kernel
139 subsystems are not documented here, nor are they tracked by this
140 attribute.
142 Changes to the thinkpad-acpi sysfs interface are only considered
143 non-experimental when they are submitted to Linux mainline, at which
144 point the changes in this interface are documented and interface_version
145 may be updated. If you are using any thinkpad-acpi features not yet
146 sent to mainline for merging, you do so on your own risk: these features
147 may disappear, or be implemented in a different and incompatible way by
148 the time they are merged in Linux mainline.
150 Changes that are backwards-compatible by nature (e.g. the addition of
151 attributes that do not change the way the other attributes work) do not
152 always warrant an update of interface_version. Therefore, one must
153 expect that an attribute might not be there, and deal with it properly
154 (an attribute not being there *is* a valid way to make it clear that a
155 feature is not available in sysfs).
157 Hot keys
158 --------
160 procfs: /proc/acpi/ibm/hotkey
161 sysfs device attribute: hotkey_*
163 In a ThinkPad, the ACPI HKEY handler is responsible for comunicating
164 some important events and also keyboard hot key presses to the operating
165 system. Enabling the hotkey functionality of thinkpad-acpi signals the
166 firmware that such a driver is present, and modifies how the ThinkPad
167 firmware will behave in many situations.
169 The driver enables the hot key feature automatically when loaded. The
170 feature can later be disabled and enabled back at runtime. The driver
171 will also restore the hot key feature to its previous state and mask
172 when it is unloaded.
174 When the hotkey feature is enabled and the hot key mask is set (see
175 below), the driver will report HKEY events in the following format:
177 ibm/hotkey HKEY 00000080 0000xxxx
179 Some of these events refer to hot key presses, but not all.
181 The driver will generate events over the input layer for hot keys and
182 radio switches, and over the ACPI netlink layer for other events. The
183 input layer support accepts the standard IOCTLs to remap the keycodes
184 assigned to each hot key.
186 The hot key bit mask allows some control over which hot keys generate
187 events. If a key is "masked" (bit set to 0 in the mask), the firmware
188 will handle it. If it is "unmasked", it signals the firmware that
189 thinkpad-acpi would prefer to handle it, if the firmware would be so
190 kind to allow it (and it often doesn't!).
192 Not all bits in the mask can be modified. Not all bits that can be
193 modified do anything. Not all hot keys can be individually controlled
194 by the mask. Some models do not support the mask at all, and in those
195 models, hot keys cannot be controlled individually. The behaviour of
196 the mask is, therefore, higly dependent on the ThinkPad model.
198 Note that unmasking some keys prevents their default behavior. For
199 example, if Fn+F5 is unmasked, that key will no longer enable/disable
200 Bluetooth by itself.
202 Note also that not all Fn key combinations are supported through ACPI.
203 For example, on the X40, the brightness, volume and "Access IBM" buttons
204 do not generate ACPI events even with this driver. They *can* be used
205 through the "ThinkPad Buttons" utility, see http://www.nongnu.org/tpb/
207 procfs notes:
209 The following commands can be written to the /proc/acpi/ibm/hotkey file:
211 echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature
212 echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature
213 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
214 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
215 ... any other 8-hex-digit mask ...
216 echo reset > /proc/acpi/ibm/hotkey -- restore the original mask
218 The procfs interface does not support NVRAM polling control. So as to
219 maintain maximum bug-to-bug compatibility, it does not report any masks,
220 nor does it allow one to manipulate the hot key mask when the firmware
221 does not support masks at all, even if NVRAM polling is in use.
223 sysfs notes:
225 hotkey_bios_enabled:
226 Returns the status of the hot keys feature when
227 thinkpad-acpi was loaded. Upon module unload, the hot
228 key feature status will be restored to this value.
230 0: hot keys were disabled
231 1: hot keys were enabled (unusual)
233 hotkey_bios_mask:
234 Returns the hot keys mask when thinkpad-acpi was loaded.
235 Upon module unload, the hot keys mask will be restored
236 to this value.
238 hotkey_enable:
239 Enables/disables the hot keys feature in the ACPI
240 firmware, and reports current status of the hot keys
241 feature. Has no effect on the NVRAM hot key polling
242 functionality.
244 0: disables the hot keys feature / feature disabled
245 1: enables the hot keys feature / feature enabled
247 hotkey_mask:
248 bit mask to enable driver-handling (and depending on
249 the firmware, ACPI event generation) for each hot key
250 (see above). Returns the current status of the hot keys
251 mask, and allows one to modify it.
253 Note: when NVRAM polling is active, the firmware mask
254 will be different from the value returned by
255 hotkey_mask. The driver will retain enabled bits for
256 hotkeys that are under NVRAM polling even if the
257 firmware refuses them, and will not set these bits on
258 the firmware hot key mask.
260 hotkey_all_mask:
261 bit mask that should enable event reporting for all
262 supported hot keys, when echoed to hotkey_mask above.
263 Unless you know which events need to be handled
264 passively (because the firmware *will* handle them
265 anyway), do *not* use hotkey_all_mask. Use
266 hotkey_recommended_mask, instead. You have been warned.
268 hotkey_recommended_mask:
269 bit mask that should enable event reporting for all
270 supported hot keys, except those which are always
271 handled by the firmware anyway. Echo it to
272 hotkey_mask above, to use.
274 hotkey_source_mask:
275 bit mask that selects which hot keys will the driver
276 poll the NVRAM for. This is auto-detected by the driver
277 based on the capabilities reported by the ACPI firmware,
278 but it can be overridden at runtime.
280 Hot keys whose bits are set in both hotkey_source_mask
281 and also on hotkey_mask are polled for in NVRAM. Only a
282 few hot keys are available through CMOS NVRAM polling.
284 Warning: when in NVRAM mode, the volume up/down/mute
285 keys are synthesized according to changes in the mixer,
286 so you have to use volume up or volume down to unmute,
287 as per the ThinkPad volume mixer user interface. When
288 in ACPI event mode, volume up/down/mute are reported as
289 separate events, but this behaviour may be corrected in
290 future releases of this driver, in which case the
291 ThinkPad volume mixer user interface semanthics will be
292 enforced.
294 hotkey_poll_freq:
295 frequency in Hz for hot key polling. It must be between
296 0 and 25 Hz. Polling is only carried out when strictly
297 needed.
299 Setting hotkey_poll_freq to zero disables polling, and
300 will cause hot key presses that require NVRAM polling
301 to never be reported.
303 Setting hotkey_poll_freq too low will cause repeated
304 pressings of the same hot key to be misreported as a
305 single key press, or to not even be detected at all.
306 The recommended polling frequency is 10Hz.
308 hotkey_radio_sw:
309 if the ThinkPad has a hardware radio switch, this
310 attribute will read 0 if the switch is in the "radios
311 disabled" postition, and 1 if the switch is in the
312 "radios enabled" position.
314 hotkey_report_mode:
315 Returns the state of the procfs ACPI event report mode
316 filter for hot keys. If it is set to 1 (the default),
317 all hot key presses are reported both through the input
318 layer and also as ACPI events through procfs (but not
319 through netlink). If it is set to 2, hot key presses
320 are reported only through the input layer.
322 This attribute is read-only in kernels 2.6.23 or later,
323 and read-write on earlier kernels.
325 May return -EPERM (write access locked out by module
326 parameter) or -EACCES (read-only).
328 wakeup_reason:
329 Set to 1 if the system is waking up because the user
330 requested a bay ejection. Set to 2 if the system is
331 waking up because the user requested the system to
332 undock. Set to zero for normal wake-ups or wake-ups
333 due to unknown reasons.
335 wakeup_hotunplug_complete:
336 Set to 1 if the system was waken up because of an
337 undock or bay ejection request, and that request
338 was sucessfully completed. At this point, it might
339 be useful to send the system back to sleep, at the
340 user's choice. Refer to HKEY events 0x4003 and
341 0x3003, below.
343 input layer notes:
345 A Hot key is mapped to a single input layer EV_KEY event, possibly
346 followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
347 code. An EV_SYN event will always be generated to mark the end of the
348 event block.
350 Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
351 used as a helper to remap keys, only. They are particularly useful when
352 remapping KEY_UNKNOWN keys.
354 The events are available in an input device, with the following id:
356 Bus: BUS_HOST
357 vendor: 0x1014 (PCI_VENDOR_ID_IBM) or
358 0x17aa (PCI_VENDOR_ID_LENOVO)
359 product: 0x5054 ("TP")
360 version: 0x4101
362 The version will have its LSB incremented if the keymap changes in a
363 backwards-compatible way. The MSB shall always be 0x41 for this input
364 device. If the MSB is not 0x41, do not use the device as described in
365 this section, as it is either something else (e.g. another input device
366 exported by a thinkpad driver, such as HDAPS) or its functionality has
367 been changed in a non-backwards compatible way.
369 Adding other event types for other functionalities shall be considered a
370 backwards-compatible change for this input device.
372 Thinkpad-acpi Hot Key event map (version 0x4101):
374 ACPI Scan
375 event code Key Notes
377 0x1001 0x00 FN+F1 -
378 0x1002 0x01 FN+F2 IBM: battery (rare)
379 Lenovo: Screen lock
381 0x1003 0x02 FN+F3 Many IBM models always report
382 this hot key, even with hot keys
383 disabled or with Fn+F3 masked
384 off
385 IBM: screen lock
386 Lenovo: battery
388 0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
389 semanthics, i.e. sleep-to-RAM).
390 It is always generate some kind
391 of event, either the hot key
392 event or a ACPI sleep button
393 event. The firmware may
394 refuse to generate further FN+F4
395 key presses until a S3 or S4 ACPI
396 sleep cycle is performed or some
397 time passes.
399 0x1005 0x04 FN+F5 Radio. Enables/disables
400 the internal BlueTooth hardware
401 and W-WAN card if left in control
402 of the firmware. Does not affect
403 the WLAN card.
404 Should be used to turn on/off all
405 radios (bluetooth+W-WAN+WLAN),
406 really.
408 0x1006 0x05 FN+F6 -
410 0x1007 0x06 FN+F7 Video output cycle.
411 Do you feel lucky today?
413 0x1008 0x07 FN+F8 IBM: toggle screen expand
414 Lenovo: configure ultranav
416 0x1009 0x08 FN+F9 -
417 .. .. ..
418 0x100B 0x0A FN+F11 -
420 0x100C 0x0B FN+F12 Sleep to disk. You are always
421 supposed to handle it yourself,
422 either through the ACPI event,
423 or through a hotkey event.
424 The firmware may refuse to
425 generate further FN+F4 key
426 press events until a S3 or S4
427 ACPI sleep cycle is performed,
428 or some time passes.
430 0x100D 0x0C FN+BACKSPACE -
431 0x100E 0x0D FN+INSERT -
432 0x100F 0x0E FN+DELETE -
434 0x1010 0x0F FN+HOME Brightness up. This key is
435 always handled by the firmware
436 in IBM ThinkPads, even when
437 unmasked. Just leave it alone.
438 For Lenovo ThinkPads with a new
439 BIOS, it has to be handled either
440 by the ACPI OSI, or by userspace.
441 0x1011 0x10 FN+END Brightness down. See brightness
442 up for details.
444 0x1012 0x11 FN+PGUP Thinklight toggle. This key is
445 always handled by the firmware,
446 even when unmasked.
448 0x1013 0x12 FN+PGDOWN -
450 0x1014 0x13 FN+SPACE Zoom key
452 0x1015 0x14 VOLUME UP Internal mixer volume up. This
453 key is always handled by the
454 firmware, even when unmasked.
455 NOTE: Lenovo seems to be changing
456 this.
457 0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
458 key is always handled by the
459 firmware, even when unmasked.
460 NOTE: Lenovo seems to be changing
461 this.
462 0x1017 0x16 MUTE Mute internal mixer. This
463 key is always handled by the
464 firmware, even when unmasked.
466 0x1018 0x17 THINKPAD Thinkpad/Access IBM/Lenovo key
468 0x1019 0x18 unknown
469 .. .. ..
470 0x1020 0x1F unknown
472 The ThinkPad firmware does not allow one to differentiate when most hot
473 keys are pressed or released (either that, or we don't know how to, yet).
474 For these keys, the driver generates a set of events for a key press and
475 immediately issues the same set of events for a key release. It is
476 unknown by the driver if the ThinkPad firmware triggered these events on
477 hot key press or release, but the firmware will do it for either one, not
478 both.
480 If a key is mapped to KEY_RESERVED, it generates no input events at all.
481 If a key is mapped to KEY_UNKNOWN, it generates an input event that
482 includes an scan code. If a key is mapped to anything else, it will
483 generate input device EV_KEY events.
485 Non hot-key ACPI HKEY event map:
486 0x5001 Lid closed
487 0x5002 Lid opened
488 0x7000 Radio Switch may have changed state
490 The above events are not propagated by the driver, except for legacy
491 compatibility purposes when hotkey_report_mode is set to 1.
493 0x2304 System is waking up from suspend to undock
494 0x2305 System is waking up from suspend to eject bay
495 0x2404 System is waking up from hibernation to undock
496 0x2405 System is waking up from hibernation to eject bay
498 The above events are never propagated by the driver.
500 0x3003 Bay ejection (see 0x2x05) complete, can sleep again
501 0x4003 Undocked (see 0x2x04), can sleep again
502 0x5009 Tablet swivel: switched to tablet mode
503 0x500A Tablet swivel: switched to normal mode
504 0x500B Tablet pen insterted into its storage bay
505 0x500C Tablet pen removed from its storage bay
506 0x5010 Brightness level changed (newer Lenovo BIOSes)
508 The above events are propagated by the driver.
510 Compatibility notes:
512 ibm-acpi and thinkpad-acpi 0.15 (mainline kernels before 2.6.23) never
513 supported the input layer, and sent events over the procfs ACPI event
514 interface.
516 To avoid sending duplicate events over the input layer and the ACPI
517 event interface, thinkpad-acpi 0.16 implements a module parameter
518 (hotkey_report_mode), and also a sysfs device attribute with the same
519 name.
521 Make no mistake here: userspace is expected to switch to using the input
522 layer interface of thinkpad-acpi, together with the ACPI netlink event
523 interface in kernels 2.6.23 and later, or with the ACPI procfs event
524 interface in kernels 2.6.22 and earlier.
526 If no hotkey_report_mode module parameter is specified (or it is set to
527 zero), the driver defaults to mode 1 (see below), and on kernels 2.6.22
528 and earlier, also allows one to change the hotkey_report_mode through
529 sysfs. In kernels 2.6.23 and later, where the netlink ACPI event
530 interface is available, hotkey_report_mode cannot be changed through
531 sysfs (it is read-only).
533 If the hotkey_report_mode module parameter is set to 1 or 2, it cannot
534 be changed later through sysfs (any writes will return -EPERM to signal
535 that hotkey_report_mode was locked. On 2.6.23 and later, where
536 hotkey_report_mode cannot be changed at all, writes will return -EACES).
538 hotkey_report_mode set to 1 makes the driver export through the procfs
539 ACPI event interface all hot key presses (which are *also* sent to the
540 input layer). This is a legacy compatibility behaviour, and it is also
541 the default mode of operation for the driver.
543 hotkey_report_mode set to 2 makes the driver filter out the hot key
544 presses from the procfs ACPI event interface, so these events will only
545 be sent through the input layer. Userspace that has been updated to use
546 the thinkpad-acpi input layer interface should set hotkey_report_mode to
547 2.
549 Hot key press events are never sent to the ACPI netlink event interface.
550 Really up-to-date userspace under kernel 2.6.23 and later is to use the
551 netlink interface and the input layer interface, and don't bother at all
552 with hotkey_report_mode.
555 Bluetooth
556 ---------
558 procfs: /proc/acpi/ibm/bluetooth
559 sysfs device attribute: bluetooth_enable
561 This feature shows the presence and current state of a ThinkPad
562 Bluetooth device in the internal ThinkPad CDC slot.
564 Procfs notes:
566 If Bluetooth is installed, the following commands can be used:
568 echo enable > /proc/acpi/ibm/bluetooth
569 echo disable > /proc/acpi/ibm/bluetooth
571 Sysfs notes:
573 If the Bluetooth CDC card is installed, it can be enabled /
574 disabled through the "bluetooth_enable" thinkpad-acpi device
575 attribute, and its current status can also be queried.
577 enable:
578 0: disables Bluetooth / Bluetooth is disabled
579 1: enables Bluetooth / Bluetooth is enabled.
581 Note: this interface will be probably be superseeded by the
582 generic rfkill class, so it is NOT to be considered stable yet.
584 Video output control -- /proc/acpi/ibm/video
585 --------------------------------------------
587 This feature allows control over the devices used for video output -
588 LCD, CRT or DVI (if available). The following commands are available:
590 echo lcd_enable > /proc/acpi/ibm/video
591 echo lcd_disable > /proc/acpi/ibm/video
592 echo crt_enable > /proc/acpi/ibm/video
593 echo crt_disable > /proc/acpi/ibm/video
594 echo dvi_enable > /proc/acpi/ibm/video
595 echo dvi_disable > /proc/acpi/ibm/video
596 echo auto_enable > /proc/acpi/ibm/video
597 echo auto_disable > /proc/acpi/ibm/video
598 echo expand_toggle > /proc/acpi/ibm/video
599 echo video_switch > /proc/acpi/ibm/video
601 Each video output device can be enabled or disabled individually.
602 Reading /proc/acpi/ibm/video shows the status of each device.
604 Automatic video switching can be enabled or disabled. When automatic
605 video switching is enabled, certain events (e.g. opening the lid,
606 docking or undocking) cause the video output device to change
607 automatically. While this can be useful, it also causes flickering
608 and, on the X40, video corruption. By disabling automatic switching,
609 the flickering or video corruption can be avoided.
611 The video_switch command cycles through the available video outputs
612 (it simulates the behavior of Fn-F7).
614 Video expansion can be toggled through this feature. This controls
615 whether the display is expanded to fill the entire LCD screen when a
616 mode with less than full resolution is used. Note that the current
617 video expansion status cannot be determined through this feature.
619 Note that on many models (particularly those using Radeon graphics
620 chips) the X driver configures the video card in a way which prevents
621 Fn-F7 from working. This also disables the video output switching
622 features of this driver, as it uses the same ACPI methods as
623 Fn-F7. Video switching on the console should still work.
625 UPDATE: There's now a patch for the X.org Radeon driver which
626 addresses this issue. Some people are reporting success with the patch
627 while others are still having problems. For more information:
629 https://bugs.freedesktop.org/show_bug.cgi?id=2000
631 ThinkLight control -- /proc/acpi/ibm/light
632 ------------------------------------------
634 The current status of the ThinkLight can be found in this file. A few
635 models which do not make the status available will show it as
636 "unknown". The available commands are:
638 echo on > /proc/acpi/ibm/light
639 echo off > /proc/acpi/ibm/light
641 Docking / undocking -- /proc/acpi/ibm/dock
642 ------------------------------------------
644 Docking and undocking (e.g. with the X4 UltraBase) requires some
645 actions to be taken by the operating system to safely make or break
646 the electrical connections with the dock.
648 The docking feature of this driver generates the following ACPI events:
650 ibm/dock GDCK 00000003 00000001 -- eject request
651 ibm/dock GDCK 00000003 00000002 -- undocked
652 ibm/dock GDCK 00000000 00000003 -- docked
654 NOTE: These events will only be generated if the laptop was docked
655 when originally booted. This is due to the current lack of support for
656 hot plugging of devices in the Linux ACPI framework. If the laptop was
657 booted while not in the dock, the following message is shown in the
658 logs:
660 Mar 17 01:42:34 aero kernel: thinkpad_acpi: dock device not present
662 In this case, no dock-related events are generated but the dock and
663 undock commands described below still work. They can be executed
664 manually or triggered by Fn key combinations (see the example acpid
665 configuration files included in the driver tarball package available
666 on the web site).
668 When the eject request button on the dock is pressed, the first event
669 above is generated. The handler for this event should issue the
670 following command:
672 echo undock > /proc/acpi/ibm/dock
674 After the LED on the dock goes off, it is safe to eject the laptop.
675 Note: if you pressed this key by mistake, go ahead and eject the
676 laptop, then dock it back in. Otherwise, the dock may not function as
677 expected.
679 When the laptop is docked, the third event above is generated. The
680 handler for this event should issue the following command to fully
681 enable the dock:
683 echo dock > /proc/acpi/ibm/dock
685 The contents of the /proc/acpi/ibm/dock file shows the current status
686 of the dock, as provided by the ACPI framework.
688 The docking support in this driver does not take care of enabling or
689 disabling any other devices you may have attached to the dock. For
690 example, a CD drive plugged into the UltraBase needs to be disabled or
691 enabled separately. See the provided example acpid configuration files
692 for how this can be accomplished.
694 There is no support yet for PCI devices that may be attached to a
695 docking station, e.g. in the ThinkPad Dock II. The driver currently
696 does not recognize, enable or disable such devices. This means that
697 the only docking stations currently supported are the X-series
698 UltraBase docks and "dumb" port replicators like the Mini Dock (the
699 latter don't need any ACPI support, actually).
701 UltraBay eject -- /proc/acpi/ibm/bay
702 ------------------------------------
704 Inserting or ejecting an UltraBay device requires some actions to be
705 taken by the operating system to safely make or break the electrical
706 connections with the device.
708 This feature generates the following ACPI events:
710 ibm/bay MSTR 00000003 00000000 -- eject request
711 ibm/bay MSTR 00000001 00000000 -- eject lever inserted
713 NOTE: These events will only be generated if the UltraBay was present
714 when the laptop was originally booted (on the X series, the UltraBay
715 is in the dock, so it may not be present if the laptop was undocked).
716 This is due to the current lack of support for hot plugging of devices
717 in the Linux ACPI framework. If the laptop was booted without the
718 UltraBay, the following message is shown in the logs:
720 Mar 17 01:42:34 aero kernel: thinkpad_acpi: bay device not present
722 In this case, no bay-related events are generated but the eject
723 command described below still works. It can be executed manually or
724 triggered by a hot key combination.
726 Sliding the eject lever generates the first event shown above. The
727 handler for this event should take whatever actions are necessary to
728 shut down the device in the UltraBay (e.g. call idectl), then issue
729 the following command:
731 echo eject > /proc/acpi/ibm/bay
733 After the LED on the UltraBay goes off, it is safe to pull out the
734 device.
736 When the eject lever is inserted, the second event above is
737 generated. The handler for this event should take whatever actions are
738 necessary to enable the UltraBay device (e.g. call idectl).
740 The contents of the /proc/acpi/ibm/bay file shows the current status
741 of the UltraBay, as provided by the ACPI framework.
743 EXPERIMENTAL warm eject support on the 600e/x, A22p and A3x (To use
744 this feature, you need to supply the experimental=1 parameter when
745 loading the module):
747 These models do not have a button near the UltraBay device to request
748 a hot eject but rather require the laptop to be put to sleep
749 (suspend-to-ram) before the bay device is ejected or inserted).
750 The sequence of steps to eject the device is as follows:
752 echo eject > /proc/acpi/ibm/bay
753 put the ThinkPad to sleep
754 remove the drive
755 resume from sleep
756 cat /proc/acpi/ibm/bay should show that the drive was removed
758 On the A3x, both the UltraBay 2000 and UltraBay Plus devices are
759 supported. Use "eject2" instead of "eject" for the second bay.
761 Note: the UltraBay eject support on the 600e/x, A22p and A3x is
762 EXPERIMENTAL and may not work as expected. USE WITH CAUTION!
764 CMOS control
765 ------------
767 procfs: /proc/acpi/ibm/cmos
768 sysfs device attribute: cmos_command
770 This feature is mostly used internally by the ACPI firmware to keep the legacy
771 CMOS NVRAM bits in sync with the current machine state, and to record this
772 state so that the ThinkPad will retain such settings across reboots.
774 Some of these commands actually perform actions in some ThinkPad models, but
775 this is expected to disappear more and more in newer models. As an example, in
776 a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
777 real, but commands 0 to 2 don't control the mixer anymore (they have been
778 phased out) and just update the NVRAM.
780 The range of valid cmos command numbers is 0 to 21, but not all have an
781 effect and the behavior varies from model to model. Here is the behavior
782 on the X40 (tpb is the ThinkPad Buttons utility):
784 0 - Related to "Volume down" key press
785 1 - Related to "Volume up" key press
786 2 - Related to "Mute on" key press
787 3 - Related to "Access IBM" key press
788 4 - Related to "LCD brightness up" key pess
789 5 - Related to "LCD brightness down" key press
790 11 - Related to "toggle screen expansion" key press/function
791 12 - Related to "ThinkLight on"
792 13 - Related to "ThinkLight off"
793 14 - Related to "ThinkLight" key press (toggle thinklight)
795 The cmos command interface is prone to firmware split-brain problems, as
796 in newer ThinkPads it is just a compatibility layer. Do not use it, it is
797 exported just as a debug tool.
799 LED control -- /proc/acpi/ibm/led
800 ---------------------------------
802 Some of the LED indicators can be controlled through this feature. The
803 available commands are:
805 echo '<led number> on' >/proc/acpi/ibm/led
806 echo '<led number> off' >/proc/acpi/ibm/led
807 echo '<led number> blink' >/proc/acpi/ibm/led
809 The <led number> range is 0 to 7. The set of LEDs that can be
810 controlled varies from model to model. Here is the mapping on the X40:
812 0 - power
813 1 - battery (orange)
814 2 - battery (green)
815 3 - UltraBase
816 4 - UltraBay
817 7 - standby
819 All of the above can be turned on and off and can be made to blink.
821 ACPI sounds -- /proc/acpi/ibm/beep
822 ----------------------------------
824 The BEEP method is used internally by the ACPI firmware to provide
825 audible alerts in various situations. This feature allows the same
826 sounds to be triggered manually.
828 The commands are non-negative integer numbers:
830 echo <number> >/proc/acpi/ibm/beep
832 The valid <number> range is 0 to 17. Not all numbers trigger sounds
833 and the sounds vary from model to model. Here is the behavior on the
834 X40:
836 0 - stop a sound in progress (but use 17 to stop 16)
837 2 - two beeps, pause, third beep ("low battery")
838 3 - single beep
839 4 - high, followed by low-pitched beep ("unable")
840 5 - single beep
841 6 - very high, followed by high-pitched beep ("AC/DC")
842 7 - high-pitched beep
843 9 - three short beeps
844 10 - very long beep
845 12 - low-pitched beep
846 15 - three high-pitched beeps repeating constantly, stop with 0
847 16 - one medium-pitched beep repeating constantly, stop with 17
848 17 - stop 16
850 Temperature sensors
851 -------------------
853 procfs: /proc/acpi/ibm/thermal
854 sysfs device attributes: (hwmon "thinkpad") temp*_input
856 Most ThinkPads include six or more separate temperature sensors but only
857 expose the CPU temperature through the standard ACPI methods. This
858 feature shows readings from up to eight different sensors on older
859 ThinkPads, and up to sixteen different sensors on newer ThinkPads.
861 For example, on the X40, a typical output may be:
862 temperatures: 42 42 45 41 36 -128 33 -128
864 On the T43/p, a typical output may be:
865 temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
867 The mapping of thermal sensors to physical locations varies depending on
868 system-board model (and thus, on ThinkPad model).
870 http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
871 tries to track down these locations for various models.
873 Most (newer?) models seem to follow this pattern:
875 1: CPU
876 2: (depends on model)
877 3: (depends on model)
878 4: GPU
879 5: Main battery: main sensor
880 6: Bay battery: main sensor
881 7: Main battery: secondary sensor
882 8: Bay battery: secondary sensor
883 9-15: (depends on model)
885 For the R51 (source: Thomas Gruber):
886 2: Mini-PCI
887 3: Internal HDD
889 For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
890 http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
891 2: System board, left side (near PCMCIA slot), reported as HDAPS temp
892 3: PCMCIA slot
893 9: MCH (northbridge) to DRAM Bus
894 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
895 card, under touchpad
896 11: Power regulator, underside of system board, below F2 key
898 The A31 has a very atypical layout for the thermal sensors
899 (source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
900 1: CPU
901 2: Main Battery: main sensor
902 3: Power Converter
903 4: Bay Battery: main sensor
904 5: MCH (northbridge)
905 6: PCMCIA/ambient
906 7: Main Battery: secondary sensor
907 8: Bay Battery: secondary sensor
910 Procfs notes:
911 Readings from sensors that are not available return -128.
912 No commands can be written to this file.
914 Sysfs notes:
915 Sensors that are not available return the ENXIO error. This
916 status may change at runtime, as there are hotplug thermal
917 sensors, like those inside the batteries and docks.
919 thinkpad-acpi thermal sensors are reported through the hwmon
920 subsystem, and follow all of the hwmon guidelines at
921 Documentation/hwmon.
924 EXPERIMENTAL: Embedded controller register dump -- /proc/acpi/ibm/ecdump
925 ------------------------------------------------------------------------
927 This feature is marked EXPERIMENTAL because the implementation
928 directly accesses hardware registers and may not work as expected. USE
929 WITH CAUTION! To use this feature, you need to supply the
930 experimental=1 parameter when loading the module.
932 This feature dumps the values of 256 embedded controller
933 registers. Values which have changed since the last time the registers
934 were dumped are marked with a star:
936 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
937 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
938 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
939 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
940 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
941 EC 0x30: 01 07 1a 00 30 04 00 00 *85 00 00 10 00 50 00 00
942 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
943 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 *bc *02 *bc
944 EC 0x60: *02 *bc *02 00 00 00 00 00 00 00 00 00 00 00 00 00
945 EC 0x70: 00 00 00 00 00 12 30 40 *24 *26 *2c *27 *20 80 *1f 80
946 EC 0x80: 00 00 00 06 *37 *0e 03 00 00 00 0e 07 00 00 00 00
947 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
948 EC 0xa0: *ff 09 ff 09 ff ff *64 00 *00 *00 *a2 41 *ff *ff *e0 00
949 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
950 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
951 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
952 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
953 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
955 This feature can be used to determine the register holding the fan
956 speed on some models. To do that, do the following:
958 - make sure the battery is fully charged
959 - make sure the fan is running
960 - run 'cat /proc/acpi/ibm/ecdump' several times, once per second or so
962 The first step makes sure various charging-related values don't
963 vary. The second ensures that the fan-related values do vary, since
964 the fan speed fluctuates a bit. The third will (hopefully) mark the
965 fan register with a star:
967 [root@x40 ibm-acpi]# cat /proc/acpi/ibm/ecdump
968 EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f
969 EC 0x00: a7 47 87 01 fe 96 00 08 01 00 cb 00 00 00 40 00
970 EC 0x10: 00 00 ff ff f4 3c 87 09 01 ff 42 01 ff ff 0d 00
971 EC 0x20: 00 00 00 00 00 00 00 00 00 00 00 03 43 00 00 80
972 EC 0x30: 01 07 1a 00 30 04 00 00 85 00 00 10 00 50 00 00
973 EC 0x40: 00 00 00 00 00 00 14 01 00 04 00 00 00 00 00 00
974 EC 0x50: 00 c0 02 0d 00 01 01 02 02 03 03 03 03 bc 02 bc
975 EC 0x60: 02 bc 02 00 00 00 00 00 00 00 00 00 00 00 00 00
976 EC 0x70: 00 00 00 00 00 12 30 40 24 27 2c 27 21 80 1f 80
977 EC 0x80: 00 00 00 06 *be 0d 03 00 00 00 0e 07 00 00 00 00
978 EC 0x90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
979 EC 0xa0: ff 09 ff 09 ff ff 64 00 00 00 a2 41 ff ff e0 00
980 EC 0xb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
981 EC 0xc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
982 EC 0xd0: 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
983 EC 0xe0: 00 00 00 00 00 00 00 00 11 20 49 04 24 06 55 03
984 EC 0xf0: 31 55 48 54 35 38 57 57 08 2f 45 73 07 65 6c 1a
986 Another set of values that varies often is the temperature
987 readings. Since temperatures don't change vary fast, you can take
988 several quick dumps to eliminate them.
990 You can use a similar method to figure out the meaning of other
991 embedded controller registers - e.g. make sure nothing else changes
992 except the charging or discharging battery to determine which
993 registers contain the current battery capacity, etc. If you experiment
994 with this, do send me your results (including some complete dumps with
995 a description of the conditions when they were taken.)
997 LCD brightness control
998 ----------------------
1000 procfs: /proc/acpi/ibm/brightness
1001 sysfs backlight device "thinkpad_screen"
1003 This feature allows software control of the LCD brightness on ThinkPad
1004 models which don't have a hardware brightness slider.
1006 It has some limitations: the LCD backlight cannot be actually turned on or
1007 off by this interface, and in many ThinkPad models, the "dim while on
1008 battery" functionality will be enabled by the BIOS when this interface is
1009 used, and cannot be controlled.
1011 On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
1012 has eight brightness levels, ranging from 0 to 7. Some of the levels
1013 may not be distinct. Later Lenovo models that implement the ACPI
1014 display backlight brightness control methods have 16 levels, ranging
1015 from 0 to 15.
1017 There are two interfaces to the firmware for direct brightness control,
1018 EC and CMOS. To select which one should be used, use the
1019 brightness_mode module parameter: brightness_mode=1 selects EC mode,
1020 brightness_mode=2 selects CMOS mode, brightness_mode=3 selects both EC
1021 and CMOS. The driver tries to autodetect which interface to use.
1023 When display backlight brightness controls are available through the
1024 standard ACPI interface, it is best to use it instead of this direct
1025 ThinkPad-specific interface. The driver will disable its native
1026 backlight brightness control interface if it detects that the standard
1027 ACPI interface is available in the ThinkPad.
1029 The brightness_enable module parameter can be used to control whether
1030 the LCD brightness control feature will be enabled when available.
1031 brightness_enable=0 forces it to be disabled. brightness_enable=1
1032 forces it to be enabled when available, even if the standard ACPI
1033 interface is also available.
1035 Procfs notes:
1037 The available commands are:
1039 echo up >/proc/acpi/ibm/brightness
1040 echo down >/proc/acpi/ibm/brightness
1041 echo 'level <level>' >/proc/acpi/ibm/brightness
1043 Sysfs notes:
1045 The interface is implemented through the backlight sysfs class, which is
1046 poorly documented at this time.
1048 Locate the thinkpad_screen device under /sys/class/backlight, and inside
1049 it there will be the following attributes:
1051 max_brightness:
1052 Reads the maximum brightness the hardware can be set to.
1053 The minimum is always zero.
1055 actual_brightness:
1056 Reads what brightness the screen is set to at this instant.
1058 brightness:
1059 Writes request the driver to change brightness to the
1060 given value. Reads will tell you what brightness the
1061 driver is trying to set the display to when "power" is set
1062 to zero and the display has not been dimmed by a kernel
1063 power management event.
1065 power:
1066 power management mode, where 0 is "display on", and 1 to 3
1067 will dim the display backlight to brightness level 0
1068 because thinkpad-acpi cannot really turn the backlight
1069 off. Kernel power management events can temporarily
1070 increase the current power management level, i.e. they can
1071 dim the display.
1074 Volume control -- /proc/acpi/ibm/volume
1075 ---------------------------------------
1077 This feature allows volume control on ThinkPad models which don't have
1078 a hardware volume knob. The available commands are:
1080 echo up >/proc/acpi/ibm/volume
1081 echo down >/proc/acpi/ibm/volume
1082 echo mute >/proc/acpi/ibm/volume
1083 echo 'level <level>' >/proc/acpi/ibm/volume
1085 The <level> number range is 0 to 15 although not all of them may be
1086 distinct. The unmute the volume after the mute command, use either the
1087 up or down command (the level command will not unmute the volume).
1088 The current volume level and mute state is shown in the file.
1090 Fan control and monitoring: fan speed, fan enable/disable
1091 ---------------------------------------------------------
1093 procfs: /proc/acpi/ibm/fan
1094 sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
1095 pwm1_enable
1096 sysfs hwmon driver attributes: fan_watchdog
1098 NOTE NOTE NOTE: fan control operations are disabled by default for
1099 safety reasons. To enable them, the module parameter "fan_control=1"
1100 must be given to thinkpad-acpi.
1102 This feature attempts to show the current fan speed, control mode and
1103 other fan data that might be available. The speed is read directly
1104 from the hardware registers of the embedded controller. This is known
1105 to work on later R, T, X and Z series ThinkPads but may show a bogus
1106 value on other models.
1108 Fan levels:
1110 Most ThinkPad fans work in "levels" at the firmware interface. Level 0
1111 stops the fan. The higher the level, the higher the fan speed, although
1112 adjacent levels often map to the same fan speed. 7 is the highest
1113 level, where the fan reaches the maximum recommended speed.
1115 Level "auto" means the EC changes the fan level according to some
1116 internal algorithm, usually based on readings from the thermal sensors.
1118 There is also a "full-speed" level, also known as "disengaged" level.
1119 In this level, the EC disables the speed-locked closed-loop fan control,
1120 and drives the fan as fast as it can go, which might exceed hardware
1121 limits, so use this level with caution.
1123 The fan usually ramps up or down slowly from one speed to another, and
1124 it is normal for the EC to take several seconds to react to fan
1125 commands. The full-speed level may take up to two minutes to ramp up to
1126 maximum speed, and in some ThinkPads, the tachometer readings go stale
1127 while the EC is transitioning to the full-speed level.
1129 WARNING WARNING WARNING: do not leave the fan disabled unless you are
1130 monitoring all of the temperature sensor readings and you are ready to
1131 enable it if necessary to avoid overheating.
1133 An enabled fan in level "auto" may stop spinning if the EC decides the
1134 ThinkPad is cool enough and doesn't need the extra airflow. This is
1135 normal, and the EC will spin the fan up if the various thermal readings
1136 rise too much.
1138 On the X40, this seems to depend on the CPU and HDD temperatures.
1139 Specifically, the fan is turned on when either the CPU temperature
1140 climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
1141 fan is turned off when the CPU temperature drops to 49 degrees and the
1142 HDD temperature drops to 41 degrees. These thresholds cannot
1143 currently be controlled.
1145 The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
1146 certain conditions are met. It will override any fan programming done
1147 through thinkpad-acpi.
1149 The thinkpad-acpi kernel driver can be programmed to revert the fan
1150 level to a safe setting if userspace does not issue one of the procfs
1151 fan commands: "enable", "disable", "level" or "watchdog", or if there
1152 are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
1153 set to 1, manual mode) within a configurable amount of time of up to
1154 120 seconds. This functionality is called fan safety watchdog.
1156 Note that the watchdog timer stops after it enables the fan. It will be
1157 rearmed again automatically (using the same interval) when one of the
1158 above mentioned fan commands is received. The fan watchdog is,
1159 therefore, not suitable to protect against fan mode changes made through
1160 means other than the "enable", "disable", and "level" procfs fan
1161 commands, or the hwmon fan control sysfs interface.
1163 Procfs notes:
1165 The fan may be enabled or disabled with the following commands:
1167 echo enable >/proc/acpi/ibm/fan
1168 echo disable >/proc/acpi/ibm/fan
1170 Placing a fan on level 0 is the same as disabling it. Enabling a fan
1171 will try to place it in a safe level if it is too slow or disabled.
1173 The fan level can be controlled with the command:
1175 echo 'level <level>' > /proc/acpi/ibm/fan
1177 Where <level> is an integer from 0 to 7, or one of the words "auto" or
1178 "full-speed" (without the quotes). Not all ThinkPads support the "auto"
1179 and "full-speed" levels. The driver accepts "disengaged" as an alias for
1180 "full-speed", and reports it as "disengaged" for backwards
1181 compatibility.
1183 On the X31 and X40 (and ONLY on those models), the fan speed can be
1184 controlled to a certain degree. Once the fan is running, it can be
1185 forced to run faster or slower with the following command:
1187 echo 'speed <speed>' > /proc/acpi/ibm/fan
1189 The sustainable range of fan speeds on the X40 appears to be from about
1190 3700 to about 7350. Values outside this range either do not have any
1191 effect or the fan speed eventually settles somewhere in that range. The
1192 fan cannot be stopped or started with this command. This functionality
1193 is incomplete, and not available through the sysfs interface.
1195 To program the safety watchdog, use the "watchdog" command.
1197 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
1199 If you want to disable the watchdog, use 0 as the interval.
1201 Sysfs notes:
1203 The sysfs interface follows the hwmon subsystem guidelines for the most
1204 part, and the exception is the fan safety watchdog.
1206 Writes to any of the sysfs attributes may return the EINVAL error if
1207 that operation is not supported in a given ThinkPad or if the parameter
1208 is out-of-bounds, and EPERM if it is forbidden. They may also return
1209 EINTR (interrupted system call), and EIO (I/O error while trying to talk
1210 to the firmware).
1212 Features not yet implemented by the driver return ENOSYS.
1214 hwmon device attribute pwm1_enable:
1215 0: PWM offline (fan is set to full-speed mode)
1216 1: Manual PWM control (use pwm1 to set fan level)
1217 2: Hardware PWM control (EC "auto" mode)
1218 3: reserved (Software PWM control, not implemented yet)
1220 Modes 0 and 2 are not supported by all ThinkPads, and the
1221 driver is not always able to detect this. If it does know a
1222 mode is unsupported, it will return -EINVAL.
1224 hwmon device attribute pwm1:
1225 Fan level, scaled from the firmware values of 0-7 to the hwmon
1226 scale of 0-255. 0 means fan stopped, 255 means highest normal
1227 speed (level 7).
1229 This attribute only commands the fan if pmw1_enable is set to 1
1230 (manual PWM control).
1232 hwmon device attribute fan1_input:
1233 Fan tachometer reading, in RPM. May go stale on certain
1234 ThinkPads while the EC transitions the PWM to offline mode,
1235 which can take up to two minutes. May return rubbish on older
1236 ThinkPads.
1238 hwmon driver attribute fan_watchdog:
1239 Fan safety watchdog timer interval, in seconds. Minimum is
1240 1 second, maximum is 120 seconds. 0 disables the watchdog.
1242 To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
1244 To start the fan in a safe mode: set pwm1_enable to 2. If that fails
1245 with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
1246 would be the safest choice, though).
1249 EXPERIMENTAL: WAN
1250 -----------------
1252 procfs: /proc/acpi/ibm/wan
1253 sysfs device attribute: wwan_enable
1255 This feature is marked EXPERIMENTAL because the implementation
1256 directly accesses hardware registers and may not work as expected. USE
1257 WITH CAUTION! To use this feature, you need to supply the
1258 experimental=1 parameter when loading the module.
1260 This feature shows the presence and current state of a W-WAN (Sierra
1261 Wireless EV-DO) device.
1263 It was tested on a Lenovo Thinkpad X60. It should probably work on other
1264 Thinkpad models which come with this module installed.
1266 Procfs notes:
1268 If the W-WAN card is installed, the following commands can be used:
1270 echo enable > /proc/acpi/ibm/wan
1271 echo disable > /proc/acpi/ibm/wan
1273 Sysfs notes:
1275 If the W-WAN card is installed, it can be enabled /
1276 disabled through the "wwan_enable" thinkpad-acpi device
1277 attribute, and its current status can also be queried.
1279 enable:
1280 0: disables WWAN card / WWAN card is disabled
1281 1: enables WWAN card / WWAN card is enabled.
1283 Note: this interface will be probably be superseeded by the
1284 generic rfkill class, so it is NOT to be considered stable yet.
1286 Multiple Commands, Module Parameters
1287 ------------------------------------
1289 Multiple commands can be written to the proc files in one shot by
1290 separating them with commas, for example:
1292 echo enable,0xffff > /proc/acpi/ibm/hotkey
1293 echo lcd_disable,crt_enable > /proc/acpi/ibm/video
1295 Commands can also be specified when loading the thinkpad-acpi module,
1296 for example:
1298 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
1300 Enabling debugging output
1301 -------------------------
1303 The module takes a debug parameter which can be used to selectively
1304 enable various classes of debugging output, for example:
1306 modprobe ibm_acpi debug=0xffff
1308 will enable all debugging output classes. It takes a bitmask, so
1309 to enable more than one output class, just add their values.
1311 Debug bitmask Description
1312 0x0001 Initialization and probing
1313 0x0002 Removal
1315 There is also a kernel build option to enable more debugging
1316 information, which may be necessary to debug driver problems.
1318 The level of debugging information output by the driver can be changed
1319 at runtime through sysfs, using the driver attribute debug_level. The
1320 attribute takes the same bitmask as the debug module parameter above.
1322 Force loading of module
1323 -----------------------
1325 If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
1326 the module parameter force_load=1. Regardless of whether this works or
1327 not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
1330 Sysfs interface changelog:
1332 0x000100: Initial sysfs support, as a single platform driver and
1333 device.
1334 0x000200: Hot key support for 32 hot keys, and radio slider switch
1335 support.
1336 0x010000: Hot keys are now handled by default over the input
1337 layer, the radio switch generates input event EV_RADIO,
1338 and the driver enables hot key handling by default in
1339 the firmware.
1341 0x020000: ABI fix: added a separate hwmon platform device and
1342 driver, which must be located by name (thinkpad)
1343 and the hwmon class for libsensors4 (lm-sensors 3)
1344 compatibility. Moved all hwmon attributes to this
1345 new platform device.
1347 0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
1348 support. If you must, use it to know you should not
1349 start an userspace NVRAM poller (allows to detect when
1350 NVRAM is compiled out by the user because it is
1351 unneeded/undesired in the first place).
1352 0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
1353 and proper hotkey_mask semanthics (version 8 of the
1354 NVRAM polling patch). Some development snapshots of
1355 0.18 had an earlier version that did strange things
1356 to hotkey_mask.