1 ThinkPad ACPI Extras Driver 2 3 Version 0.25 4 October 16th, 2013 5 6 Borislav Deianov <borislav@users.sf.net> 7 Henrique de Moraes Holschuh <hmh@hmh.eng.br> 8 http://ibm-acpi.sf.net/ 9 10 11This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It 12supports various features of these laptops which are accessible 13through the ACPI and ACPI EC framework, but not otherwise fully 14supported by the generic Linux ACPI drivers. 15 16This driver used to be named ibm-acpi until kernel 2.6.21 and release 170.13-20070314. It used to be in the drivers/acpi tree, but it was 18moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel 192.6.22, and release 0.14. It was moved to drivers/platform/x86 for 20kernel 2.6.29 and release 0.22. 21 22The driver is named "thinkpad-acpi". In some places, like module 23names and log messages, "thinkpad_acpi" is used because of userspace 24issues. 25 26"tpacpi" is used as a shorthand where "thinkpad-acpi" would be too 27long due to length limitations on some Linux kernel versions. 28 29Status 30------ 31 32The features currently supported are the following (see below for 33detailed description): 34 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 49 50A compatibility table by model and feature is maintained on the web 51site, http://ibm-acpi.sf.net/. I appreciate any success or failure 52reports, especially if they add to or correct the compatibility table. 53Please include the following information in your report: 54 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 61 62Any other comments or patches are also more than welcome. 63 64 65Installation 66------------ 67 68If you are compiling this driver as included in the Linux kernel 69sources, look for the CONFIG_THINKPAD_ACPI Kconfig option. 70It is located on the menu path: "Device Drivers" -> "X86 Platform 71Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras". 72 73 74Features 75-------- 76 77The driver exports two different interfaces to userspace, which can be 78used to access the features it provides. One is a legacy procfs-based 79interface, which will be removed at some time in the future. The other 80is a new sysfs-based interface which is not complete yet. 81 82The procfs interface creates the /proc/acpi/ibm directory. There is a 83file under that directory for each feature it supports. The procfs 84interface is mostly frozen, and will change very little if at all: it 85will not be extended to add any new functionality in the driver, instead 86all new functionality will be implemented on the sysfs interface. 87 88The sysfs interface tries to blend in the generic Linux sysfs subsystems 89and classes as much as possible. Since some of these subsystems are not 90yet ready or stabilized, it is expected that this interface will change, 91and any and all userspace programs must deal with it. 92 93 94Notes about the sysfs interface: 95 96Unlike what was done with the procfs interface, correctness when talking 97to the sysfs interfaces will be enforced, as will correctness in the 98thinkpad-acpi's implementation of sysfs interfaces. 99 100Also, any bugs in the thinkpad-acpi sysfs driver code or in the 101thinkpad-acpi's implementation of the sysfs interfaces will be fixed for 102maximum correctness, even if that means changing an interface in 103non-compatible ways. As these interfaces mature both in the kernel and 104in thinkpad-acpi, such changes should become quite rare. 105 106Applications interfacing to the thinkpad-acpi sysfs interfaces must 107follow all sysfs guidelines and correctly process all errors (the sysfs 108interface makes extensive use of errors). File descriptors and open / 109close operations to the sysfs inodes must also be properly implemented. 110 111The version of thinkpad-acpi's sysfs interface is exported by the driver 112as a driver attribute (see below). 113 114Sysfs driver attributes are on the driver's sysfs attribute space, 115for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and 116/sys/bus/platform/drivers/thinkpad_hwmon/ 117 118Sysfs device attributes are on the thinkpad_acpi device sysfs attribute 119space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/. 120 121Sysfs device attributes for the sensors and fan are on the 122thinkpad_hwmon device's sysfs attribute space, but you should locate it 123looking for a hwmon device with the name attribute of "thinkpad", or 124better yet, through libsensors. For 4.14+ sysfs attributes were moved to the 125hwmon device (/sys/bus/platform/devices/thinkpad_hwmon/hwmon/hwmon? or 126/sys/class/hwmon/hwmon?). 127 128Driver version 129-------------- 130 131procfs: /proc/acpi/ibm/driver 132sysfs driver attribute: version 133 134The driver name and version. No commands can be written to this file. 135 136 137Sysfs interface version 138----------------------- 139 140sysfs driver attribute: interface_version 141 142Version 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 147 148The sysfs interface version changelog for the driver can be found at the 149end of this document. Changes to the sysfs interface done by the kernel 150subsystems are not documented here, nor are they tracked by this 151attribute. 152 153Changes to the thinkpad-acpi sysfs interface are only considered 154non-experimental when they are submitted to Linux mainline, at which 155point the changes in this interface are documented and interface_version 156may be updated. If you are using any thinkpad-acpi features not yet 157sent to mainline for merging, you do so on your own risk: these features 158may disappear, or be implemented in a different and incompatible way by 159the time they are merged in Linux mainline. 160 161Changes that are backwards-compatible by nature (e.g. the addition of 162attributes that do not change the way the other attributes work) do not 163always warrant an update of interface_version. Therefore, one must 164expect 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 166feature is not available in sysfs). 167 168 169Hot keys 170-------- 171 172procfs: /proc/acpi/ibm/hotkey 173sysfs device attribute: hotkey_* 174 175In a ThinkPad, the ACPI HKEY handler is responsible for communicating 176some important events and also keyboard hot key presses to the operating 177system. Enabling the hotkey functionality of thinkpad-acpi signals the 178firmware that such a driver is present, and modifies how the ThinkPad 179firmware will behave in many situations. 180 181The driver enables the HKEY ("hot key") event reporting automatically 182when loaded, and disables it when it is removed. 183 184The driver will report HKEY events in the following format: 185 186 ibm/hotkey HKEY 00000080 0000xxxx 187 188Some of these events refer to hot key presses, but not all of them. 189 190The driver will generate events over the input layer for hot keys and 191radio switches, and over the ACPI netlink layer for other events. The 192input layer support accepts the standard IOCTLs to remap the keycodes 193assigned to each hot key. 194 195The hot key bit mask allows some control over which hot keys generate 196events. If a key is "masked" (bit set to 0 in the mask), the firmware 197will handle it. If it is "unmasked", it signals the firmware that 198thinkpad-acpi would prefer to handle it, if the firmware would be so 199kind to allow it (and it often doesn't!). 200 201Not all bits in the mask can be modified. Not all bits that can be 202modified do anything. Not all hot keys can be individually controlled 203by the mask. Some models do not support the mask at all. The behaviour 204of the mask is, therefore, highly dependent on the ThinkPad model. 205 206The driver will filter out any unmasked hotkeys, so even if the firmware 207doesn't allow disabling an specific hotkey, the driver will not report 208events for unmasked hotkeys. 209 210Note that unmasking some keys prevents their default behavior. For 211example, if Fn+F5 is unmasked, that key will no longer enable/disable 212Bluetooth by itself in firmware. 213 214Note also that not all Fn key combinations are supported through ACPI 215depending on the ThinkPad model and firmware version. On those 216ThinkPads, it is still possible to support some extra hotkeys by 217polling the "CMOS NVRAM" at least 10 times per second. The driver 218attempts to enables this functionality automatically when required. 219 220procfs notes: 221 222The following commands can be written to the /proc/acpi/ibm/hotkey file: 223 224 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 228 229The following commands have been deprecated and will cause the kernel 230to log a warning: 231 232 echo enable > /proc/acpi/ibm/hotkey -- does nothing 233 echo disable > /proc/acpi/ibm/hotkey -- returns an error 234 235The procfs interface does not support NVRAM polling control. So as to 236maintain maximum bug-to-bug compatibility, it does not report any masks, 237nor does it allow one to manipulate the hot key mask when the firmware 238does not support masks at all, even if NVRAM polling is in use. 239 240sysfs notes: 241 242 hotkey_bios_enabled: 243 DEPRECATED, WILL BE REMOVED SOON. 244 245 Returns 0. 246 247 hotkey_bios_mask: 248 DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE. 249 250 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. 255 256 hotkey_enable: 257 DEPRECATED, WILL BE REMOVED SOON. 258 259 0: returns -EPERM 260 1: does nothing 261 262 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. 267 268 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. 275 276 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. 282 283 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. 288 289 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. 293 294 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). 303 304 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. 308 309 Setting hotkey_poll_freq to zero disables polling, and 310 will cause hot key presses that require NVRAM polling 311 to never be reported. 312 313 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. 317 318 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. 323 324 This attribute has poll()/select() support. 325 326 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. 330 331 This attribute has poll()/select() support. 332 333 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. 339 340 This attribute has poll()/select() support. 341 342 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. 349 350 This attribute has poll()/select() support. 351 352input layer notes: 353 354A Hot key is mapped to a single input layer EV_KEY event, possibly 355followed by an EV_MSC MSC_SCAN event that shall contain that key's scan 356code. An EV_SYN event will always be generated to mark the end of the 357event block. 358 359Do not use the EV_MSC MSC_SCAN events to process keys. They are to be 360used as a helper to remap keys, only. They are particularly useful when 361remapping KEY_UNKNOWN keys. 362 363The events are available in an input device, with the following id: 364 365 Bus: BUS_HOST 366 vendor: 0x1014 (PCI_VENDOR_ID_IBM) or 367 0x17aa (PCI_VENDOR_ID_LENOVO) 368 product: 0x5054 ("TP") 369 version: 0x4101 370 371The version will have its LSB incremented if the keymap changes in a 372backwards-compatible way. The MSB shall always be 0x41 for this input 373device. If the MSB is not 0x41, do not use the device as described in 374this section, as it is either something else (e.g. another input device 375exported by a thinkpad driver, such as HDAPS) or its functionality has 376been changed in a non-backwards compatible way. 377 378Adding other event types for other functionalities shall be considered a 379backwards-compatible change for this input device. 380 381Thinkpad-acpi Hot Key event map (version 0x4101): 382 383ACPI Scan 384event code Key Notes 385 3860x1001 0x00 FN+F1 - 387 3880x1002 0x01 FN+F2 IBM: battery (rare) 389 Lenovo: Screen lock 390 3910x1003 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 398 3990x1004 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. 409 4100x1005 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. 418 4190x1006 0x05 FN+F6 - 420 4210x1007 0x06 FN+F7 Video output cycle. 422 Do you feel lucky today? 423 4240x1008 0x07 FN+F8 IBM: toggle screen expand 425 Lenovo: configure UltraNav, 426 or toggle screen expand 427 4280x1009 0x08 FN+F9 - 429 .. .. .. 4300x100B 0x0A FN+F11 - 431 4320x100C 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. 441 4420x100D 0x0C FN+BACKSPACE - 4430x100E 0x0D FN+INSERT - 4440x100F 0x0E FN+DELETE - 445 4460x1010 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. 4550x1011 0x10 FN+END Brightness down. See brightness 456 up for details. 457 4580x1012 0x11 FN+PGUP ThinkLight toggle. This key is 459 always handled by the firmware, 460 even when unmasked. 461 4620x1013 0x12 FN+PGDOWN - 463 4640x1014 0x13 FN+SPACE Zoom key 465 4660x1015 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. 4710x1016 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. 4760x1017 0x16 MUTE Mute internal mixer. This 477 key is always handled by the 478 firmware, even when unmasked. 479 4800x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key 481 4820x1019 0x18 unknown 483.. .. .. 4840x1020 0x1F unknown 485 486The ThinkPad firmware does not allow one to differentiate when most hot 487keys are pressed or released (either that, or we don't know how to, yet). 488For these keys, the driver generates a set of events for a key press and 489immediately issues the same set of events for a key release. It is 490unknown by the driver if the ThinkPad firmware triggered these events on 491hot key press or release, but the firmware will do it for either one, not 492both. 493 494If a key is mapped to KEY_RESERVED, it generates no input events at all. 495If a key is mapped to KEY_UNKNOWN, it generates an input event that 496includes an scan code. If a key is mapped to anything else, it will 497generate input device EV_KEY events. 498 499In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW 500events for switches: 501 502SW_RFKILL_ALL T60 and later hardware rfkill rocker switch 503SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A 504 505Non hotkey ACPI HKEY event map: 506------------------------------- 507 508Events that are never propagated by the driver: 509 5100x2304 System is waking up from suspend to undock 5110x2305 System is waking up from suspend to eject bay 5120x2404 System is waking up from hibernation to undock 5130x2405 System is waking up from hibernation to eject bay 5140x5001 Lid closed 5150x5002 Lid opened 5160x5009 Tablet swivel: switched to tablet mode 5170x500A Tablet swivel: switched to normal mode 5180x5010 Brightness level changed/control event 5190x6000 KEYBOARD: Numlock key pressed 5200x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED) 5210x7000 Radio Switch may have changed state 522 523 524Events that are propagated by the driver to userspace: 525 5260x2313 ALARM: System is waking up from suspend because 527 the battery is nearly empty 5280x2413 ALARM: System is waking up from hibernation because 529 the battery is nearly empty 5300x3003 Bay ejection (see 0x2x05) complete, can sleep again 5310x3006 Bay hotplug request (hint to power up SATA link when 532 the optical drive tray is ejected) 5330x4003 Undocked (see 0x2x04), can sleep again 5340x4010 Docked into hotplug port replicator (non-ACPI dock) 5350x4011 Undocked from hotplug port replicator (non-ACPI dock) 5360x500B Tablet pen inserted into its storage bay 5370x500C Tablet pen removed from its storage bay 5380x6011 ALARM: battery is too hot 5390x6012 ALARM: battery is extremely hot 5400x6021 ALARM: a sensor is too hot 5410x6022 ALARM: a sensor is extremely hot 5420x6030 System thermal table changed 5430x6032 Thermal Control command set completion (DYTC, Windows) 5440x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED) 5450x60C0 X1 Yoga 2016, Tablet mode status changed 5460x60F0 Thermal Transformation changed (GMTS, Windows) 547 548Battery nearly empty alarms are a last resort attempt to get the 549operating system to hibernate or shutdown cleanly (0x2313), or shutdown 550cleanly (0x2413) before power is lost. They must be acted upon, as the 551wake up caused by the firmware will have negated most safety nets... 552 553When any of the "too hot" alarms happen, according to Lenovo the user 554should suspend or hibernate the laptop (and in the case of battery 555alarms, unplug the AC adapter) to let it cool down. These alarms do 556signal that something is wrong, they should never happen on normal 557operating conditions. 558 559The "extremely hot" alarms are emergencies. According to Lenovo, the 560operating system is to force either an immediate suspend or hibernate 561cycle, or a system shutdown. Obviously, something is very wrong if this 562happens. 563 564 565Brightness hotkey notes: 566 567Don't mess with the brightness hotkeys in a Thinkpad. If you want 568notifications for OSD, use the sysfs backlight class event support. 569 570The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events 571automatically for the cases were userspace has to do something to 572implement brightness changes. When you override these events, you will 573either fail to handle properly the ThinkPads that require explicit 574action to change backlight brightness, or the ThinkPads that require 575that no action be taken to work properly. 576 577 578Bluetooth 579--------- 580 581procfs: /proc/acpi/ibm/bluetooth 582sysfs device attribute: bluetooth_enable (deprecated) 583sysfs rfkill class: switch "tpacpi_bluetooth_sw" 584 585This feature shows the presence and current state of a ThinkPad 586Bluetooth device in the internal ThinkPad CDC slot. 587 588If the ThinkPad supports it, the Bluetooth state is stored in NVRAM, 589so it is kept across reboots and power-off. 590 591Procfs notes: 592 593If Bluetooth is installed, the following commands can be used: 594 595 echo enable > /proc/acpi/ibm/bluetooth 596 echo disable > /proc/acpi/ibm/bluetooth 597 598Sysfs notes: 599 600 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. 603 604 enable: 605 0: disables Bluetooth / Bluetooth is disabled 606 1: enables Bluetooth / Bluetooth is enabled. 607 608 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. 611 612 rfkill controller switch "tpacpi_bluetooth_sw": refer to 613 Documentation/rfkill.txt for details. 614 615 616Video output control -- /proc/acpi/ibm/video 617-------------------------------------------- 618 619This feature allows control over the devices used for video output - 620LCD, CRT or DVI (if available). The following commands are available: 621 622 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 632 633NOTE: Access to this feature is restricted to processes owning the 634CAP_SYS_ADMIN capability for safety reasons, as it can interact badly 635enough with some versions of X.org to crash it. 636 637Each video output device can be enabled or disabled individually. 638Reading /proc/acpi/ibm/video shows the status of each device. 639 640Automatic video switching can be enabled or disabled. When automatic 641video switching is enabled, certain events (e.g. opening the lid, 642docking or undocking) cause the video output device to change 643automatically. While this can be useful, it also causes flickering 644and, on the X40, video corruption. By disabling automatic switching, 645the flickering or video corruption can be avoided. 646 647The video_switch command cycles through the available video outputs 648(it simulates the behavior of Fn-F7). 649 650Video expansion can be toggled through this feature. This controls 651whether the display is expanded to fill the entire LCD screen when a 652mode with less than full resolution is used. Note that the current 653video expansion status cannot be determined through this feature. 654 655Note that on many models (particularly those using Radeon graphics 656chips) the X driver configures the video card in a way which prevents 657Fn-F7 from working. This also disables the video output switching 658features of this driver, as it uses the same ACPI methods as 659Fn-F7. Video switching on the console should still work. 660 661UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000 662 663 664ThinkLight control 665------------------ 666 667procfs: /proc/acpi/ibm/light 668sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED 669 670procfs notes: 671 672The ThinkLight status can be read and set through the procfs interface. A 673few models which do not make the status available will show the ThinkLight 674status as "unknown". The available commands are: 675 676 echo on > /proc/acpi/ibm/light 677 echo off > /proc/acpi/ibm/light 678 679sysfs notes: 680 681The ThinkLight sysfs interface is documented by the LED class 682documentation, in Documentation/leds/leds-class.txt. The ThinkLight LED name 683is "tpacpi::thinklight". 684 685Due to limitations in the sysfs LED class, if the status of the ThinkLight 686cannot be read or if it is unknown, thinkpad-acpi will report it as "off". 687It is impossible to know if the status returned through sysfs is valid. 688 689 690CMOS/UCMS control 691----------------- 692 693procfs: /proc/acpi/ibm/cmos 694sysfs device attribute: cmos_command 695 696This feature is mostly used internally by the ACPI firmware to keep the legacy 697CMOS NVRAM bits in sync with the current machine state, and to record this 698state so that the ThinkPad will retain such settings across reboots. 699 700Some of these commands actually perform actions in some ThinkPad models, but 701this is expected to disappear more and more in newer models. As an example, in 702a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for 703real, but commands 0 to 2 don't control the mixer anymore (they have been 704phased out) and just update the NVRAM. 705 706The range of valid cmos command numbers is 0 to 21, but not all have an 707effect and the behavior varies from model to model. Here is the behavior 708on the X40 (tpb is the ThinkPad Buttons utility): 709 710 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) 720 721The cmos command interface is prone to firmware split-brain problems, as 722in newer ThinkPads it is just a compatibility layer. Do not use it, it is 723exported just as a debug tool. 724 725 726LED control 727----------- 728 729procfs: /proc/acpi/ibm/led 730sysfs attributes: as per LED class, see below for names 731 732Some of the LED indicators can be controlled through this feature. On 733some older ThinkPad models, it is possible to query the status of the 734LED indicators as well. Newer ThinkPads cannot query the real status 735of the LED indicators. 736 737Because misuse of the LEDs could induce an unaware user to perform 738dangerous actions (like undocking or ejecting a bay device while the 739buses are still active), or mask an important alarm (such as a nearly 740empty battery, or a broken battery), access to most LEDs is 741restricted. 742 743Unrestricted access to all LEDs requires that thinkpad-acpi be 744compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled. 745Distributions must never enable this option. Individual users that 746are aware of the consequences are welcome to enabling it. 747 748Audio mute and microphone mute LEDs are supported, but currently not 749visible to userspace. They are used by the snd-hda-intel audio driver. 750 751procfs notes: 752 753The available commands are: 754 755 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 758 759The <LED number> range is 0 to 15. The set of LEDs that can be 760controlled varies from model to model. Here is the common ThinkPad 761mapping: 762 763 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) 776 777All of the above can be turned on and off and can be made to blink. 778 779sysfs notes: 780 781The ThinkPad LED sysfs interface is described in detail by the LED class 782documentation, in Documentation/leds/leds-class.txt. 783 784The 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". 790 791Due to limitations in the sysfs LED class, if the status of the LED 792indicators cannot be read due to an error, thinkpad-acpi will report it as 793a brightness of zero (same as LED off). 794 795If the thinkpad firmware doesn't support reading the current status, 796trying to read the current LED brightness will just return whatever 797brightness was last written to that attribute. 798 799These LEDs can blink using hardware acceleration. To request that a 800ThinkPad indicator LED should blink in hardware accelerated mode, use the 801"timer" trigger, and leave the delay_on and delay_off parameters set to 802zero (to request hardware acceleration autodetection). 803 804LEDs that are known not to exist in a given ThinkPad model are not 805made available through the sysfs interface. If you have a dock and you 806notice there are LEDs listed for your ThinkPad that do not exist (and 807are not in the dock), or if you notice that there are missing LEDs, 808a report to ibm-acpi-devel@lists.sourceforge.net is appreciated. 809 810 811ACPI sounds -- /proc/acpi/ibm/beep 812---------------------------------- 813 814The BEEP method is used internally by the ACPI firmware to provide 815audible alerts in various situations. This feature allows the same 816sounds to be triggered manually. 817 818The commands are non-negative integer numbers: 819 820 echo <number> >/proc/acpi/ibm/beep 821 822The valid <number> range is 0 to 17. Not all numbers trigger sounds 823and the sounds vary from model to model. Here is the behavior on the 824X40: 825 826 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 16 839 840 841Temperature sensors 842------------------- 843 844procfs: /proc/acpi/ibm/thermal 845sysfs device attributes: (hwmon "thinkpad") temp*_input 846 847Most ThinkPads include six or more separate temperature sensors but only 848expose the CPU temperature through the standard ACPI methods. This 849feature shows readings from up to eight different sensors on older 850ThinkPads, and up to sixteen different sensors on newer ThinkPads. 851 852For example, on the X40, a typical output may be: 853temperatures: 42 42 45 41 36 -128 33 -128 854 855On the T43/p, a typical output may be: 856temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128 857 858The mapping of thermal sensors to physical locations varies depending on 859system-board model (and thus, on ThinkPad model). 860 861http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that 862tries to track down these locations for various models. 863 864Most (newer?) models seem to follow this pattern: 865 8661: CPU 8672: (depends on model) 8683: (depends on model) 8694: GPU 8705: Main battery: main sensor 8716: Bay battery: main sensor 8727: Main battery: secondary sensor 8738: Bay battery: secondary sensor 8749-15: (depends on model) 875 876For the R51 (source: Thomas Gruber): 8772: Mini-PCI 8783: Internal HDD 879 880For the T43, T43/p (source: Shmidoax/Thinkwiki.org) 881http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p 8822: System board, left side (near PCMCIA slot), reported as HDAPS temp 8833: PCMCIA slot 8849: MCH (northbridge) to DRAM Bus 88510: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI 886 card, under touchpad 88711: Power regulator, underside of system board, below F2 key 888 889The A31 has a very atypical layout for the thermal sensors 890(source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31) 8911: CPU 8922: Main Battery: main sensor 8933: Power Converter 8944: Bay Battery: main sensor 8955: MCH (northbridge) 8966: PCMCIA/ambient 8977: Main Battery: secondary sensor 8988: Bay Battery: secondary sensor 899 900 901Procfs notes: 902 Readings from sensors that are not available return -128. 903 No commands can be written to this file. 904 905Sysfs 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. 909 910 thinkpad-acpi thermal sensors are reported through the hwmon 911 subsystem, and follow all of the hwmon guidelines at 912 Documentation/hwmon. 913 914EXPERIMENTAL: Embedded controller register dump 915----------------------------------------------- 916 917This feature is not included in the thinkpad driver anymore. 918Instead the EC can be accessed through /sys/kernel/debug/ec with 919a userspace tool which can be found here: 920ftp://ftp.suse.com/pub/people/trenn/sources/ec 921 922Use it to determine the register holding the fan 923speed 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 927 928Often fan and temperature values vary between 929readings. Since temperatures don't change vary fast, you can take 930several quick dumps to eliminate them. 931 932You can use a similar method to figure out the meaning of other 933embedded controller registers - e.g. make sure nothing else changes 934except the charging or discharging battery to determine which 935registers contain the current battery capacity, etc. If you experiment 936with this, do send me your results (including some complete dumps with 937a description of the conditions when they were taken.) 938 939 940LCD brightness control 941---------------------- 942 943procfs: /proc/acpi/ibm/brightness 944sysfs backlight device "thinkpad_screen" 945 946This feature allows software control of the LCD brightness on ThinkPad 947models which don't have a hardware brightness slider. 948 949It has some limitations: the LCD backlight cannot be actually turned 950on or off by this interface, it just controls the backlight brightness 951level. 952 953On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control 954has eight brightness levels, ranging from 0 to 7. Some of the levels 955may not be distinct. Later Lenovo models that implement the ACPI 956display backlight brightness control methods have 16 levels, ranging 957from 0 to 15. 958 959For IBM ThinkPads, there are two interfaces to the firmware for direct 960brightness control, EC and UCMS (or CMOS). To select which one should be 961used, use the brightness_mode module parameter: brightness_mode=1 selects 962EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC 963mode with NVRAM backing (so that brightness changes are remembered across 964shutdown/reboot). 965 966The driver tries to select which interface to use from a table of 967defaults for each ThinkPad model. If it makes a wrong choice, please 968report this as a bug, so that we can fix it. 969 970Lenovo ThinkPads only support brightness_mode=2 (UCMS). 971 972When display backlight brightness controls are available through the 973standard ACPI interface, it is best to use it instead of this direct 974ThinkPad-specific interface. The driver will disable its native 975backlight brightness control interface if it detects that the standard 976ACPI interface is available in the ThinkPad. 977 978If you want to use the thinkpad-acpi backlight brightness control 979instead of the generic ACPI video backlight brightness control for some 980reason, you should use the acpi_backlight=vendor kernel parameter. 981 982The brightness_enable module parameter can be used to control whether 983the LCD brightness control feature will be enabled when available. 984brightness_enable=0 forces it to be disabled. brightness_enable=1 985forces it to be enabled when available, even if the standard ACPI 986interface is also available. 987 988Procfs notes: 989 990 The available commands are: 991 992 echo up >/proc/acpi/ibm/brightness 993 echo down >/proc/acpi/ibm/brightness 994 echo 'level <level>' >/proc/acpi/ibm/brightness 995 996Sysfs notes: 997 998The interface is implemented through the backlight sysfs class, which is 999poorly documented at this time. 1000 1001Locate the thinkpad_screen device under /sys/class/backlight, and inside 1002it there will be the following attributes: 1003 1004 max_brightness: 1005 Reads the maximum brightness the hardware can be set to. 1006 The minimum is always zero. 1007 1008 actual_brightness: 1009 Reads what brightness the screen is set to at this instant. 1010 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. 1017 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. 1025 1026 1027WARNING: 1028 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. 1035 1036 1037Volume control (Console Audio control) 1038-------------------------------------- 1039 1040procfs: /proc/acpi/ibm/volume 1041ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC" 1042 1043NOTE: by default, the volume control interface operates in read-only 1044mode, as it is supposed to be used for on-screen-display purposes. 1045The read/write mode can be enabled through the use of the 1046"volume_control=1" module parameter. 1047 1048NOTE: distros are urged to not enable volume_control by default, this 1049should be done by the local admin only. The ThinkPad UI is for the 1050console audio control to be done through the volume keys only, and for 1051the desktop environment to just provide on-screen-display feedback. 1052Software volume control should be done only in the main AC97/HDA 1053mixer. 1054 1055 1056About the ThinkPad Console Audio control: 1057 1058ThinkPads have a built-in amplifier and muting circuit that drives the 1059console headphone and speakers. This circuit is after the main AC97 1060or HDA mixer in the audio path, and under exclusive control of the 1061firmware. 1062 1063ThinkPads have three special hotkeys to interact with the console 1064audio control: volume up, volume down and mute. 1065 1066It is worth noting that the normal way the mute function works (on 1067ThinkPads that do not have a "mute LED") is: 1068 10691. 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. 1071 10722. Press either volume key to unmute the ThinkPad (it will _not_ 1073 change the volume, it will just unmute). 1074 1075This is a very superior design when compared to the cheap software-only 1076mute-toggle solution found on normal consumer laptops: you can be 1077absolutely sure the ThinkPad will not make noise if you press the mute 1078button, no matter the previous state. 1079 1080The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain 1081amplifiers driving the speakers and headphone output, and the firmware 1082also handles volume control for the headphone and speakers on these 1083ThinkPads without any help from the operating system (this volume 1084control stage exists after the main AC97 or HDA mixer in the audio 1085path). 1086 1087The newer Lenovo models only have firmware mute control, and depend on 1088the main HDA mixer to do volume control (which is done by the operating 1089system). In this case, the volume keys are filtered out for unmute 1090key press (there are some firmware bugs in this area) and delivered as 1091normal key presses to the operating system (thinkpad-acpi is not 1092involved). 1093 1094 1095The ThinkPad-ACPI volume control: 1096 1097The preferred way to interact with the Console Audio control is the 1098ALSA interface. 1099 1100The legacy procfs interface allows one to read the current state, 1101and if volume control is enabled, accepts the following commands: 1102 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 1108 1109The <level> number range is 0 to 14 although not all of them may be 1110distinct. To unmute the volume after the mute command, use either the 1111up or down command (the level command will not unmute the volume), or 1112the unmute command. 1113 1114You can use the volume_capabilities parameter to tell the driver 1115whether your thinkpad has volume control or mute-only control: 1116volume_capabilities=1 for mixers with mute and volume control, 1117volume_capabilities=2 for mixers with only mute control. 1118 1119If the driver misdetects the capabilities for your ThinkPad model, 1120please report this to ibm-acpi-devel@lists.sourceforge.net, so that we 1121can update the driver. 1122 1123There are two strategies for volume control. To select which one 1124should be used, use the volume_mode module parameter: volume_mode=1 1125selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing 1126(so that volume/mute changes are remembered across shutdown/reboot). 1127 1128The driver will operate in volume_mode=3 by default. If that does not 1129work well on your ThinkPad model, please report this to 1130ibm-acpi-devel@lists.sourceforge.net. 1131 1132The driver supports the standard ALSA module parameters. If the ALSA 1133mixer is disabled, the driver will disable all volume functionality. 1134 1135 1136Fan control and monitoring: fan speed, fan enable/disable 1137--------------------------------------------------------- 1138 1139procfs: /proc/acpi/ibm/fan 1140sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1, 1141 pwm1_enable, fan2_input 1142sysfs hwmon driver attributes: fan_watchdog 1143 1144NOTE NOTE NOTE: fan control operations are disabled by default for 1145safety reasons. To enable them, the module parameter "fan_control=1" 1146must be given to thinkpad-acpi. 1147 1148This feature attempts to show the current fan speed, control mode and 1149other fan data that might be available. The speed is read directly 1150from the hardware registers of the embedded controller. This is known 1151to work on later R, T, X and Z series ThinkPads but may show a bogus 1152value on other models. 1153 1154Some Lenovo ThinkPads support a secondary fan. This fan cannot be 1155controlled separately, it shares the main fan control. 1156 1157Fan levels: 1158 1159Most ThinkPad fans work in "levels" at the firmware interface. Level 0 1160stops the fan. The higher the level, the higher the fan speed, although 1161adjacent levels often map to the same fan speed. 7 is the highest 1162level, where the fan reaches the maximum recommended speed. 1163 1164Level "auto" means the EC changes the fan level according to some 1165internal algorithm, usually based on readings from the thermal sensors. 1166 1167There is also a "full-speed" level, also known as "disengaged" level. 1168In this level, the EC disables the speed-locked closed-loop fan control, 1169and drives the fan as fast as it can go, which might exceed hardware 1170limits, so use this level with caution. 1171 1172The fan usually ramps up or down slowly from one speed to another, and 1173it is normal for the EC to take several seconds to react to fan 1174commands. The full-speed level may take up to two minutes to ramp up to 1175maximum speed, and in some ThinkPads, the tachometer readings go stale 1176while the EC is transitioning to the full-speed level. 1177 1178WARNING WARNING WARNING: do not leave the fan disabled unless you are 1179monitoring all of the temperature sensor readings and you are ready to 1180enable it if necessary to avoid overheating. 1181 1182An enabled fan in level "auto" may stop spinning if the EC decides the 1183ThinkPad is cool enough and doesn't need the extra airflow. This is 1184normal, and the EC will spin the fan up if the various thermal readings 1185rise too much. 1186 1187On the X40, this seems to depend on the CPU and HDD temperatures. 1188Specifically, the fan is turned on when either the CPU temperature 1189climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The 1190fan is turned off when the CPU temperature drops to 49 degrees and the 1191HDD temperature drops to 41 degrees. These thresholds cannot 1192currently be controlled. 1193 1194The ThinkPad's ACPI DSDT code will reprogram the fan on its own when 1195certain conditions are met. It will override any fan programming done 1196through thinkpad-acpi. 1197 1198The thinkpad-acpi kernel driver can be programmed to revert the fan 1199level to a safe setting if userspace does not issue one of the procfs 1200fan commands: "enable", "disable", "level" or "watchdog", or if there 1201are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is 1202set to 1, manual mode) within a configurable amount of time of up to 1203120 seconds. This functionality is called fan safety watchdog. 1204 1205Note that the watchdog timer stops after it enables the fan. It will be 1206rearmed again automatically (using the same interval) when one of the 1207above mentioned fan commands is received. The fan watchdog is, 1208therefore, not suitable to protect against fan mode changes made through 1209means other than the "enable", "disable", and "level" procfs fan 1210commands, or the hwmon fan control sysfs interface. 1211 1212Procfs notes: 1213 1214The fan may be enabled or disabled with the following commands: 1215 1216 echo enable >/proc/acpi/ibm/fan 1217 echo disable >/proc/acpi/ibm/fan 1218 1219Placing a fan on level 0 is the same as disabling it. Enabling a fan 1220will try to place it in a safe level if it is too slow or disabled. 1221 1222The fan level can be controlled with the command: 1223 1224 echo 'level <level>' > /proc/acpi/ibm/fan 1225 1226Where <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" 1228and "full-speed" levels. The driver accepts "disengaged" as an alias for 1229"full-speed", and reports it as "disengaged" for backwards 1230compatibility. 1231 1232On the X31 and X40 (and ONLY on those models), the fan speed can be 1233controlled to a certain degree. Once the fan is running, it can be 1234forced to run faster or slower with the following command: 1235 1236 echo 'speed <speed>' > /proc/acpi/ibm/fan 1237 1238The sustainable range of fan speeds on the X40 appears to be from about 12393700 to about 7350. Values outside this range either do not have any 1240effect or the fan speed eventually settles somewhere in that range. The 1241fan cannot be stopped or started with this command. This functionality 1242is incomplete, and not available through the sysfs interface. 1243 1244To program the safety watchdog, use the "watchdog" command. 1245 1246 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan 1247 1248If you want to disable the watchdog, use 0 as the interval. 1249 1250Sysfs notes: 1251 1252The sysfs interface follows the hwmon subsystem guidelines for the most 1253part, and the exception is the fan safety watchdog. 1254 1255Writes to any of the sysfs attributes may return the EINVAL error if 1256that operation is not supported in a given ThinkPad or if the parameter 1257is out-of-bounds, and EPERM if it is forbidden. They may also return 1258EINTR (interrupted system call), and EIO (I/O error while trying to talk 1259to the firmware). 1260 1261Features not yet implemented by the driver return ENOSYS. 1262 1263hwmon 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) 1268 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. 1272 1273hwmon 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). 1277 1278 This attribute only commands the fan if pmw1_enable is set to 1 1279 (manual PWM control). 1280 1281hwmon 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. 1286 1287hwmon 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. 1291 1292hwmon 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. 1295 1296To stop the fan: set pwm1 to zero, and pwm1_enable to 1. 1297 1298To start the fan in a safe mode: set pwm1_enable to 2. If that fails 1299with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255 1300would be the safest choice, though). 1301 1302 1303WAN 1304--- 1305 1306procfs: /proc/acpi/ibm/wan 1307sysfs device attribute: wwan_enable (deprecated) 1308sysfs rfkill class: switch "tpacpi_wwan_sw" 1309 1310This feature shows the presence and current state of the built-in 1311Wireless WAN device. 1312 1313If the ThinkPad supports it, the WWAN state is stored in NVRAM, 1314so it is kept across reboots and power-off. 1315 1316It was tested on a Lenovo ThinkPad X60. It should probably work on other 1317ThinkPad models which come with this module installed. 1318 1319Procfs notes: 1320 1321If the W-WAN card is installed, the following commands can be used: 1322 1323 echo enable > /proc/acpi/ibm/wan 1324 echo disable > /proc/acpi/ibm/wan 1325 1326Sysfs notes: 1327 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. 1331 1332 enable: 1333 0: disables WWAN card / WWAN card is disabled 1334 1: enables WWAN card / WWAN card is enabled. 1335 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. 1339 1340 rfkill controller switch "tpacpi_wwan_sw": refer to 1341 Documentation/rfkill.txt for details. 1342 1343 1344EXPERIMENTAL: UWB 1345----------------- 1346 1347This feature is considered EXPERIMENTAL because it has not been extensively 1348tested and validated in various ThinkPad models yet. The feature may not 1349work as expected. USE WITH CAUTION! To use this feature, you need to supply 1350the experimental=1 parameter when loading the module. 1351 1352sysfs rfkill class: switch "tpacpi_uwb_sw" 1353 1354This feature exports an rfkill controller for the UWB device, if one is 1355present and enabled in the BIOS. 1356 1357Sysfs notes: 1358 1359 rfkill controller switch "tpacpi_uwb_sw": refer to 1360 Documentation/rfkill.txt for details. 1361 1362Adaptive keyboard 1363----------------- 1364 1365sysfs device attribute: adaptive_kbd_mode 1366 1367This sysfs attribute controls the keyboard "face" that will be shown on the 1368Lenovo X1 Carbon 2nd gen (2014)'s adaptive keyboard. The value can be read 1369and set. 1370 13711 = Home mode 13722 = Web-browser mode 13733 = Web-conference mode 13744 = Function mode 13755 = Layflat mode 1376 1377For more details about which buttons will appear depending on the mode, please 1378review the laptop's user guide: 1379http://www.lenovo.com/shop/americas/content/user_guides/x1carbon_2_ug_en.pdf 1380 1381Multiple Commands, Module Parameters 1382------------------------------------ 1383 1384Multiple commands can be written to the proc files in one shot by 1385separating them with commas, for example: 1386 1387 echo enable,0xffff > /proc/acpi/ibm/hotkey 1388 echo lcd_disable,crt_enable > /proc/acpi/ibm/video 1389 1390Commands can also be specified when loading the thinkpad-acpi module, 1391for example: 1392 1393 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable 1394 1395 1396Enabling debugging output 1397------------------------- 1398 1399The module takes a debug parameter which can be used to selectively 1400enable various classes of debugging output, for example: 1401 1402 modprobe thinkpad_acpi debug=0xffff 1403 1404will enable all debugging output classes. It takes a bitmask, so 1405to enable more than one output class, just add their values. 1406 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 1418 1419There is also a kernel build option to enable more debugging 1420information, which may be necessary to debug driver problems. 1421 1422The level of debugging information output by the driver can be changed 1423at runtime through sysfs, using the driver attribute debug_level. The 1424attribute takes the same bitmask as the debug module parameter above. 1425 1426 1427Force loading of module 1428----------------------- 1429 1430If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify 1431the module parameter force_load=1. Regardless of whether this works or 1432not, please contact ibm-acpi-devel@lists.sourceforge.net with a report. 1433 1434 1435Sysfs interface changelog: 1436 14370x000100: Initial sysfs support, as a single platform driver and 1438 device. 14390x000200: Hot key support for 32 hot keys, and radio slider switch 1440 support. 14410x010000: 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. 1445 14460x020000: 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. 1451 14520x020100: 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). 14570x020101: 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. 1462 14630x020200: Add poll()/select() support to the following attributes: 1464 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason 1465 14660x020300: hotkey enable/disable support removed, attributes 1467 hotkey_bios_enabled and hotkey_enable deprecated and 1468 marked for removal. 1469 14700x020400: 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. 1473 14740x020500: 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. 1478 14790x020600: Marker for backlight change event support. 1480 14810x020700: Support for mute-only mixers. 1482 Volume control in read-only mode by default. 1483 Marker for ALSA mixer support. 1484 14850x030000: Thermal and fan sysfs attributes were moved to the hwmon 1486 device instead of being attached to the backing platform 1487 device. 1488
