1=========================== 2ThinkPad ACPI Extras Driver 3=========================== 4 5Version 0.25 6 7October 16th, 2013 8 9- Borislav Deianov <borislav@users.sf.net> 10- Henrique de Moraes Holschuh <hmh@hmh.eng.br> 11 12http://ibm-acpi.sf.net/ 13 14This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It 15supports various features of these laptops which are accessible 16through the ACPI and ACPI EC framework, but not otherwise fully 17supported by the generic Linux ACPI drivers. 18 19This driver used to be named ibm-acpi until kernel 2.6.21 and release 200.13-20070314. It used to be in the drivers/acpi tree, but it was 21moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel 222.6.22, and release 0.14. It was moved to drivers/platform/x86 for 23kernel 2.6.29 and release 0.22. 24 25The driver is named "thinkpad-acpi". In some places, like module 26names and log messages, "thinkpad_acpi" is used because of userspace 27issues. 28 29"tpacpi" is used as a shorthand where "thinkpad-acpi" would be too 30long due to length limitations on some Linux kernel versions. 31 32Status 33------ 34 35The features currently supported are the following (see below for 36detailed description): 37 38 - Fn key combinations 39 - Bluetooth enable and disable 40 - video output switching, expansion control 41 - ThinkLight on and off 42 - CMOS/UCMS control 43 - LED control 44 - ACPI sounds 45 - temperature sensors 46 - Experimental: embedded controller register dump 47 - LCD brightness control 48 - Volume control 49 - Fan control and monitoring: fan speed, fan enable/disable 50 - WAN enable and disable 51 - UWB enable and disable 52 - LCD Shadow (PrivacyGuard) enable and disable 53 - Lap mode sensor 54 - Setting keyboard language 55 - WWAN Antenna type 56 - Auxmac 57 58A compatibility table by model and feature is maintained on the web 59site, http://ibm-acpi.sf.net/. I appreciate any success or failure 60reports, especially if they add to or correct the compatibility table. 61Please include the following information in your report: 62 63 - ThinkPad model name 64 - a copy of your ACPI tables, using the "acpidump" utility 65 - a copy of the output of dmidecode, with serial numbers 66 and UUIDs masked off 67 - which driver features work and which don't 68 - the observed behavior of non-working features 69 70Any other comments or patches are also more than welcome. 71 72 73Installation 74------------ 75 76If you are compiling this driver as included in the Linux kernel 77sources, look for the CONFIG_THINKPAD_ACPI Kconfig option. 78It is located on the menu path: "Device Drivers" -> "X86 Platform 79Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras". 80 81 82Features 83-------- 84 85The driver exports two different interfaces to userspace, which can be 86used to access the features it provides. One is a legacy procfs-based 87interface, which will be removed at some time in the future. The other 88is a new sysfs-based interface which is not complete yet. 89 90The procfs interface creates the /proc/acpi/ibm directory. There is a 91file under that directory for each feature it supports. The procfs 92interface is mostly frozen, and will change very little if at all: it 93will not be extended to add any new functionality in the driver, instead 94all new functionality will be implemented on the sysfs interface. 95 96The sysfs interface tries to blend in the generic Linux sysfs subsystems 97and classes as much as possible. Since some of these subsystems are not 98yet ready or stabilized, it is expected that this interface will change, 99and any and all userspace programs must deal with it. 100 101 102Notes about the sysfs interface 103^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 104 105Unlike what was done with the procfs interface, correctness when talking 106to the sysfs interfaces will be enforced, as will correctness in the 107thinkpad-acpi's implementation of sysfs interfaces. 108 109Also, any bugs in the thinkpad-acpi sysfs driver code or in the 110thinkpad-acpi's implementation of the sysfs interfaces will be fixed for 111maximum correctness, even if that means changing an interface in 112non-compatible ways. As these interfaces mature both in the kernel and 113in thinkpad-acpi, such changes should become quite rare. 114 115Applications interfacing to the thinkpad-acpi sysfs interfaces must 116follow all sysfs guidelines and correctly process all errors (the sysfs 117interface makes extensive use of errors). File descriptors and open / 118close operations to the sysfs inodes must also be properly implemented. 119 120The version of thinkpad-acpi's sysfs interface is exported by the driver 121as a driver attribute (see below). 122 123Sysfs driver attributes are on the driver's sysfs attribute space, 124for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and 125/sys/bus/platform/drivers/thinkpad_hwmon/ 126 127Sysfs device attributes are on the thinkpad_acpi device sysfs attribute 128space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/. 129 130Sysfs device attributes for the sensors and fan are on the 131thinkpad_hwmon device's sysfs attribute space, but you should locate it 132looking for a hwmon device with the name attribute of "thinkpad", or 133better yet, through libsensors. For 4.14+ sysfs attributes were moved to the 134hwmon device (/sys/bus/platform/devices/thinkpad_hwmon/hwmon/hwmon? or 135/sys/class/hwmon/hwmon?). 136 137Driver version 138-------------- 139 140procfs: /proc/acpi/ibm/driver 141 142sysfs driver attribute: version 143 144The driver name and version. No commands can be written to this file. 145 146 147Sysfs interface version 148----------------------- 149 150sysfs driver attribute: interface_version 151 152Version of the thinkpad-acpi sysfs interface, as an unsigned long 153(output in hex format: 0xAAAABBCC), where: 154 155 AAAA 156 - major revision 157 BB 158 - minor revision 159 CC 160 - bugfix revision 161 162The sysfs interface version changelog for the driver can be found at the 163end of this document. Changes to the sysfs interface done by the kernel 164subsystems are not documented here, nor are they tracked by this 165attribute. 166 167Changes to the thinkpad-acpi sysfs interface are only considered 168non-experimental when they are submitted to Linux mainline, at which 169point the changes in this interface are documented and interface_version 170may be updated. If you are using any thinkpad-acpi features not yet 171sent to mainline for merging, you do so on your own risk: these features 172may disappear, or be implemented in a different and incompatible way by 173the time they are merged in Linux mainline. 174 175Changes that are backwards-compatible by nature (e.g. the addition of 176attributes that do not change the way the other attributes work) do not 177always warrant an update of interface_version. Therefore, one must 178expect that an attribute might not be there, and deal with it properly 179(an attribute not being there *is* a valid way to make it clear that a 180feature is not available in sysfs). 181 182 183Hot keys 184-------- 185 186procfs: /proc/acpi/ibm/hotkey 187 188sysfs device attribute: hotkey_* 189 190In a ThinkPad, the ACPI HKEY handler is responsible for communicating 191some important events and also keyboard hot key presses to the operating 192system. Enabling the hotkey functionality of thinkpad-acpi signals the 193firmware that such a driver is present, and modifies how the ThinkPad 194firmware will behave in many situations. 195 196The driver enables the HKEY ("hot key") event reporting automatically 197when loaded, and disables it when it is removed. 198 199The driver will report HKEY events in the following format:: 200 201 ibm/hotkey HKEY 00000080 0000xxxx 202 203Some of these events refer to hot key presses, but not all of them. 204 205The driver will generate events over the input layer for hot keys and 206radio switches, and over the ACPI netlink layer for other events. The 207input layer support accepts the standard IOCTLs to remap the keycodes 208assigned to each hot key. 209 210The hot key bit mask allows some control over which hot keys generate 211events. If a key is "masked" (bit set to 0 in the mask), the firmware 212will handle it. If it is "unmasked", it signals the firmware that 213thinkpad-acpi would prefer to handle it, if the firmware would be so 214kind to allow it (and it often doesn't!). 215 216Not all bits in the mask can be modified. Not all bits that can be 217modified do anything. Not all hot keys can be individually controlled 218by the mask. Some models do not support the mask at all. The behaviour 219of the mask is, therefore, highly dependent on the ThinkPad model. 220 221The driver will filter out any unmasked hotkeys, so even if the firmware 222doesn't allow disabling an specific hotkey, the driver will not report 223events for unmasked hotkeys. 224 225Note that unmasking some keys prevents their default behavior. For 226example, if Fn+F5 is unmasked, that key will no longer enable/disable 227Bluetooth by itself in firmware. 228 229Note also that not all Fn key combinations are supported through ACPI 230depending on the ThinkPad model and firmware version. On those 231ThinkPads, it is still possible to support some extra hotkeys by 232polling the "CMOS NVRAM" at least 10 times per second. The driver 233attempts to enables this functionality automatically when required. 234 235procfs notes 236^^^^^^^^^^^^ 237 238The following commands can be written to the /proc/acpi/ibm/hotkey file:: 239 240 echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys 241 echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys 242 ... any other 8-hex-digit mask ... 243 echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask 244 245The following commands have been deprecated and will cause the kernel 246to log a warning:: 247 248 echo enable > /proc/acpi/ibm/hotkey -- does nothing 249 echo disable > /proc/acpi/ibm/hotkey -- returns an error 250 251The procfs interface does not support NVRAM polling control. So as to 252maintain maximum bug-to-bug compatibility, it does not report any masks, 253nor does it allow one to manipulate the hot key mask when the firmware 254does not support masks at all, even if NVRAM polling is in use. 255 256sysfs notes 257^^^^^^^^^^^ 258 259 hotkey_bios_enabled: 260 DEPRECATED, WILL BE REMOVED SOON. 261 262 Returns 0. 263 264 hotkey_bios_mask: 265 DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE. 266 267 Returns the hot keys mask when thinkpad-acpi was loaded. 268 Upon module unload, the hot keys mask will be restored 269 to this value. This is always 0x80c, because those are 270 the hotkeys that were supported by ancient firmware 271 without mask support. 272 273 hotkey_enable: 274 DEPRECATED, WILL BE REMOVED SOON. 275 276 0: returns -EPERM 277 1: does nothing 278 279 hotkey_mask: 280 bit mask to enable reporting (and depending on 281 the firmware, ACPI event generation) for each hot key 282 (see above). Returns the current status of the hot keys 283 mask, and allows one to modify it. 284 285 hotkey_all_mask: 286 bit mask that should enable event reporting for all 287 supported hot keys, when echoed to hotkey_mask above. 288 Unless you know which events need to be handled 289 passively (because the firmware *will* handle them 290 anyway), do *not* use hotkey_all_mask. Use 291 hotkey_recommended_mask, instead. You have been warned. 292 293 hotkey_recommended_mask: 294 bit mask that should enable event reporting for all 295 supported hot keys, except those which are always 296 handled by the firmware anyway. Echo it to 297 hotkey_mask above, to use. This is the default mask 298 used by the driver. 299 300 hotkey_source_mask: 301 bit mask that selects which hot keys will the driver 302 poll the NVRAM for. This is auto-detected by the driver 303 based on the capabilities reported by the ACPI firmware, 304 but it can be overridden at runtime. 305 306 Hot keys whose bits are set in hotkey_source_mask are 307 polled for in NVRAM, and reported as hotkey events if 308 enabled in hotkey_mask. Only a few hot keys are 309 available through CMOS NVRAM polling. 310 311 Warning: when in NVRAM mode, the volume up/down/mute 312 keys are synthesized according to changes in the mixer, 313 which uses a single volume up or volume down hotkey 314 press to unmute, as per the ThinkPad volume mixer user 315 interface. When in ACPI event mode, volume up/down/mute 316 events are reported by the firmware and can behave 317 differently (and that behaviour changes with firmware 318 version -- not just with firmware models -- as well as 319 OSI(Linux) state). 320 321 hotkey_poll_freq: 322 frequency in Hz for hot key polling. It must be between 323 0 and 25 Hz. Polling is only carried out when strictly 324 needed. 325 326 Setting hotkey_poll_freq to zero disables polling, and 327 will cause hot key presses that require NVRAM polling 328 to never be reported. 329 330 Setting hotkey_poll_freq too low may cause repeated 331 pressings of the same hot key to be misreported as a 332 single key press, or to not even be detected at all. 333 The recommended polling frequency is 10Hz. 334 335 hotkey_radio_sw: 336 If the ThinkPad has a hardware radio switch, this 337 attribute will read 0 if the switch is in the "radios 338 disabled" position, and 1 if the switch is in the 339 "radios enabled" position. 340 341 This attribute has poll()/select() support. 342 343 hotkey_tablet_mode: 344 If the ThinkPad has tablet capabilities, this attribute 345 will read 0 if the ThinkPad is in normal mode, and 346 1 if the ThinkPad is in tablet mode. 347 348 This attribute has poll()/select() support. 349 350 wakeup_reason: 351 Set to 1 if the system is waking up because the user 352 requested a bay ejection. Set to 2 if the system is 353 waking up because the user requested the system to 354 undock. Set to zero for normal wake-ups or wake-ups 355 due to unknown reasons. 356 357 This attribute has poll()/select() support. 358 359 wakeup_hotunplug_complete: 360 Set to 1 if the system was waken up because of an 361 undock or bay ejection request, and that request 362 was successfully completed. At this point, it might 363 be useful to send the system back to sleep, at the 364 user's choice. Refer to HKEY events 0x4003 and 365 0x3003, below. 366 367 This attribute has poll()/select() support. 368 369input layer notes 370^^^^^^^^^^^^^^^^^ 371 372A Hot key is mapped to a single input layer EV_KEY event, possibly 373followed by an EV_MSC MSC_SCAN event that shall contain that key's scan 374code. An EV_SYN event will always be generated to mark the end of the 375event block. 376 377Do not use the EV_MSC MSC_SCAN events to process keys. They are to be 378used as a helper to remap keys, only. They are particularly useful when 379remapping KEY_UNKNOWN keys. 380 381The events are available in an input device, with the following id: 382 383 ============== ============================== 384 Bus BUS_HOST 385 vendor 0x1014 (PCI_VENDOR_ID_IBM) or 386 0x17aa (PCI_VENDOR_ID_LENOVO) 387 product 0x5054 ("TP") 388 version 0x4101 389 ============== ============================== 390 391The version will have its LSB incremented if the keymap changes in a 392backwards-compatible way. The MSB shall always be 0x41 for this input 393device. If the MSB is not 0x41, do not use the device as described in 394this section, as it is either something else (e.g. another input device 395exported by a thinkpad driver, such as HDAPS) or its functionality has 396been changed in a non-backwards compatible way. 397 398Adding other event types for other functionalities shall be considered a 399backwards-compatible change for this input device. 400 401Thinkpad-acpi Hot Key event map (version 0x4101): 402 403======= ======= ============== ============================================== 404ACPI Scan 405event code Key Notes 406======= ======= ============== ============================================== 4070x1001 0x00 FN+F1 - 408 4090x1002 0x01 FN+F2 IBM: battery (rare) 410 Lenovo: Screen lock 411 4120x1003 0x02 FN+F3 Many IBM models always report 413 this hot key, even with hot keys 414 disabled or with Fn+F3 masked 415 off 416 IBM: screen lock, often turns 417 off the ThinkLight as side-effect 418 Lenovo: battery 419 4200x1004 0x03 FN+F4 Sleep button (ACPI sleep button 421 semantics, i.e. sleep-to-RAM). 422 It always generates some kind 423 of event, either the hot key 424 event or an ACPI sleep button 425 event. The firmware may 426 refuse to generate further FN+F4 427 key presses until a S3 or S4 ACPI 428 sleep cycle is performed or some 429 time passes. 430 4310x1005 0x04 FN+F5 Radio. Enables/disables 432 the internal Bluetooth hardware 433 and W-WAN card if left in control 434 of the firmware. Does not affect 435 the WLAN card. 436 Should be used to turn on/off all 437 radios (Bluetooth+W-WAN+WLAN), 438 really. 439 4400x1006 0x05 FN+F6 - 441 4420x1007 0x06 FN+F7 Video output cycle. 443 Do you feel lucky today? 444 4450x1008 0x07 FN+F8 IBM: toggle screen expand 446 Lenovo: configure UltraNav, 447 or toggle screen expand. 448 On newer platforms (2024+) 449 replaced by 0x131f (see below) 450 4510x1009 0x08 FN+F9 - 452 453... ... ... ... 454 4550x100B 0x0A FN+F11 - 456 4570x100C 0x0B FN+F12 Sleep to disk. You are always 458 supposed to handle it yourself, 459 either through the ACPI event, 460 or through a hotkey event. 461 The firmware may refuse to 462 generate further FN+F12 key 463 press events until a S3 or S4 464 ACPI sleep cycle is performed, 465 or some time passes. 466 4670x100D 0x0C FN+BACKSPACE - 4680x100E 0x0D FN+INSERT - 4690x100F 0x0E FN+DELETE - 470 4710x1010 0x0F FN+HOME Brightness up. This key is 472 always handled by the firmware 473 in IBM ThinkPads, even when 474 unmasked. Just leave it alone. 475 For Lenovo ThinkPads with a new 476 BIOS, it has to be handled either 477 by the ACPI OSI, or by userspace. 478 The driver does the right thing, 479 never mess with this. 4800x1011 0x10 FN+END Brightness down. See brightness 481 up for details. 482 4830x1012 0x11 FN+PGUP ThinkLight toggle. This key is 484 always handled by the firmware, 485 even when unmasked. 486 4870x1013 0x12 FN+PGDOWN - 488 4890x1014 0x13 FN+SPACE Zoom key 490 4910x1015 0x14 VOLUME UP Internal mixer volume up. This 492 key is always handled by the 493 firmware, even when unmasked. 494 NOTE: Lenovo seems to be changing 495 this. 4960x1016 0x15 VOLUME DOWN Internal mixer volume up. This 497 key is always handled by the 498 firmware, even when unmasked. 499 NOTE: Lenovo seems to be changing 500 this. 5010x1017 0x16 MUTE Mute internal mixer. This 502 key is always handled by the 503 firmware, even when unmasked. 504 5050x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key 506 5070x1019 0x18 unknown 508 5090x131f ... FN+F8 Platform Mode change. 510 Implemented in driver. 511 512... ... ... 513 5140x1020 0x1F unknown 515======= ======= ============== ============================================== 516 517The ThinkPad firmware does not allow one to differentiate when most hot 518keys are pressed or released (either that, or we don't know how to, yet). 519For these keys, the driver generates a set of events for a key press and 520immediately issues the same set of events for a key release. It is 521unknown by the driver if the ThinkPad firmware triggered these events on 522hot key press or release, but the firmware will do it for either one, not 523both. 524 525If a key is mapped to KEY_RESERVED, it generates no input events at all. 526If a key is mapped to KEY_UNKNOWN, it generates an input event that 527includes an scan code. If a key is mapped to anything else, it will 528generate input device EV_KEY events. 529 530In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW 531events for switches: 532 533============== ============================================== 534SW_RFKILL_ALL T60 and later hardware rfkill rocker switch 535SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A 536============== ============================================== 537 538Non hotkey ACPI HKEY event map 539------------------------------ 540 541Events that are never propagated by the driver: 542 543====== ================================================== 5440x2304 System is waking up from suspend to undock 5450x2305 System is waking up from suspend to eject bay 5460x2404 System is waking up from hibernation to undock 5470x2405 System is waking up from hibernation to eject bay 5480x5001 Lid closed 5490x5002 Lid opened 5500x5009 Tablet swivel: switched to tablet mode 5510x500A Tablet swivel: switched to normal mode 5520x5010 Brightness level changed/control event 5530x6000 KEYBOARD: Numlock key pressed 5540x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED) 5550x7000 Radio Switch may have changed state 556====== ================================================== 557 558 559Events that are propagated by the driver to userspace: 560 561====== ===================================================== 5620x2313 ALARM: System is waking up from suspend because 563 the battery is nearly empty 5640x2413 ALARM: System is waking up from hibernation because 565 the battery is nearly empty 5660x3003 Bay ejection (see 0x2x05) complete, can sleep again 5670x3006 Bay hotplug request (hint to power up SATA link when 568 the optical drive tray is ejected) 5690x4003 Undocked (see 0x2x04), can sleep again 5700x4010 Docked into hotplug port replicator (non-ACPI dock) 5710x4011 Undocked from hotplug port replicator (non-ACPI dock) 5720x500B Tablet pen inserted into its storage bay 5730x500C Tablet pen removed from its storage bay 5740x6011 ALARM: battery is too hot 5750x6012 ALARM: battery is extremely hot 5760x6021 ALARM: a sensor is too hot 5770x6022 ALARM: a sensor is extremely hot 5780x6030 System thermal table changed 5790x6032 Thermal Control command set completion (DYTC, Windows) 5800x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED) 5810x60C0 X1 Yoga 2016, Tablet mode status changed 5820x60F0 Thermal Transformation changed (GMTS, Windows) 583====== ===================================================== 584 585Battery nearly empty alarms are a last resort attempt to get the 586operating system to hibernate or shutdown cleanly (0x2313), or shutdown 587cleanly (0x2413) before power is lost. They must be acted upon, as the 588wake up caused by the firmware will have negated most safety nets... 589 590When any of the "too hot" alarms happen, according to Lenovo the user 591should suspend or hibernate the laptop (and in the case of battery 592alarms, unplug the AC adapter) to let it cool down. These alarms do 593signal that something is wrong, they should never happen on normal 594operating conditions. 595 596The "extremely hot" alarms are emergencies. According to Lenovo, the 597operating system is to force either an immediate suspend or hibernate 598cycle, or a system shutdown. Obviously, something is very wrong if this 599happens. 600 601 602Brightness hotkey notes 603^^^^^^^^^^^^^^^^^^^^^^^ 604 605Don't mess with the brightness hotkeys in a Thinkpad. If you want 606notifications for OSD, use the sysfs backlight class event support. 607 608The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events 609automatically for the cases were userspace has to do something to 610implement brightness changes. When you override these events, you will 611either fail to handle properly the ThinkPads that require explicit 612action to change backlight brightness, or the ThinkPads that require 613that no action be taken to work properly. 614 615 616Bluetooth 617--------- 618 619procfs: /proc/acpi/ibm/bluetooth 620 621sysfs device attribute: bluetooth_enable (deprecated) 622 623sysfs rfkill class: switch "tpacpi_bluetooth_sw" 624 625This feature shows the presence and current state of a ThinkPad 626Bluetooth device in the internal ThinkPad CDC slot. 627 628If the ThinkPad supports it, the Bluetooth state is stored in NVRAM, 629so it is kept across reboots and power-off. 630 631Procfs notes 632^^^^^^^^^^^^ 633 634If Bluetooth is installed, the following commands can be used:: 635 636 echo enable > /proc/acpi/ibm/bluetooth 637 echo disable > /proc/acpi/ibm/bluetooth 638 639Sysfs notes 640^^^^^^^^^^^ 641 642 If the Bluetooth CDC card is installed, it can be enabled / 643 disabled through the "bluetooth_enable" thinkpad-acpi device 644 attribute, and its current status can also be queried. 645 646 enable: 647 648 - 0: disables Bluetooth / Bluetooth is disabled 649 - 1: enables Bluetooth / Bluetooth is enabled. 650 651 Note: this interface has been superseded by the generic rfkill 652 class. It has been deprecated, and it will be removed in year 653 2010. 654 655 rfkill controller switch "tpacpi_bluetooth_sw": refer to 656 Documentation/driver-api/rfkill.rst for details. 657 658 659Video output control -- /proc/acpi/ibm/video 660-------------------------------------------- 661 662This feature allows control over the devices used for video output - 663LCD, CRT or DVI (if available). The following commands are available:: 664 665 echo lcd_enable > /proc/acpi/ibm/video 666 echo lcd_disable > /proc/acpi/ibm/video 667 echo crt_enable > /proc/acpi/ibm/video 668 echo crt_disable > /proc/acpi/ibm/video 669 echo dvi_enable > /proc/acpi/ibm/video 670 echo dvi_disable > /proc/acpi/ibm/video 671 echo auto_enable > /proc/acpi/ibm/video 672 echo auto_disable > /proc/acpi/ibm/video 673 echo expand_toggle > /proc/acpi/ibm/video 674 echo video_switch > /proc/acpi/ibm/video 675 676NOTE: 677 Access to this feature is restricted to processes owning the 678 CAP_SYS_ADMIN capability for safety reasons, as it can interact badly 679 enough with some versions of X.org to crash it. 680 681Each video output device can be enabled or disabled individually. 682Reading /proc/acpi/ibm/video shows the status of each device. 683 684Automatic video switching can be enabled or disabled. When automatic 685video switching is enabled, certain events (e.g. opening the lid, 686docking or undocking) cause the video output device to change 687automatically. While this can be useful, it also causes flickering 688and, on the X40, video corruption. By disabling automatic switching, 689the flickering or video corruption can be avoided. 690 691The video_switch command cycles through the available video outputs 692(it simulates the behavior of Fn-F7). 693 694Video expansion can be toggled through this feature. This controls 695whether the display is expanded to fill the entire LCD screen when a 696mode with less than full resolution is used. Note that the current 697video expansion status cannot be determined through this feature. 698 699Note that on many models (particularly those using Radeon graphics 700chips) the X driver configures the video card in a way which prevents 701Fn-F7 from working. This also disables the video output switching 702features of this driver, as it uses the same ACPI methods as 703Fn-F7. Video switching on the console should still work. 704 705UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000 706 707 708ThinkLight control 709------------------ 710 711procfs: /proc/acpi/ibm/light 712 713sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED 714 715procfs notes 716^^^^^^^^^^^^ 717 718The ThinkLight status can be read and set through the procfs interface. A 719few models which do not make the status available will show the ThinkLight 720status as "unknown". The available commands are:: 721 722 echo on > /proc/acpi/ibm/light 723 echo off > /proc/acpi/ibm/light 724 725sysfs notes 726^^^^^^^^^^^ 727 728The ThinkLight sysfs interface is documented by the LED class 729documentation, in Documentation/leds/leds-class.rst. The ThinkLight LED name 730is "tpacpi::thinklight". 731 732Due to limitations in the sysfs LED class, if the status of the ThinkLight 733cannot be read or if it is unknown, thinkpad-acpi will report it as "off". 734It is impossible to know if the status returned through sysfs is valid. 735 736 737CMOS/UCMS control 738----------------- 739 740procfs: /proc/acpi/ibm/cmos 741 742sysfs device attribute: cmos_command 743 744This feature is mostly used internally by the ACPI firmware to keep the legacy 745CMOS NVRAM bits in sync with the current machine state, and to record this 746state so that the ThinkPad will retain such settings across reboots. 747 748Some of these commands actually perform actions in some ThinkPad models, but 749this is expected to disappear more and more in newer models. As an example, in 750a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for 751real, but commands 0 to 2 don't control the mixer anymore (they have been 752phased out) and just update the NVRAM. 753 754The range of valid cmos command numbers is 0 to 21, but not all have an 755effect and the behavior varies from model to model. Here is the behavior 756on the X40 (tpb is the ThinkPad Buttons utility): 757 758 - 0 - Related to "Volume down" key press 759 - 1 - Related to "Volume up" key press 760 - 2 - Related to "Mute on" key press 761 - 3 - Related to "Access IBM" key press 762 - 4 - Related to "LCD brightness up" key press 763 - 5 - Related to "LCD brightness down" key press 764 - 11 - Related to "toggle screen expansion" key press/function 765 - 12 - Related to "ThinkLight on" 766 - 13 - Related to "ThinkLight off" 767 - 14 - Related to "ThinkLight" key press (toggle ThinkLight) 768 769The cmos command interface is prone to firmware split-brain problems, as 770in newer ThinkPads it is just a compatibility layer. Do not use it, it is 771exported just as a debug tool. 772 773 774LED control 775----------- 776 777procfs: /proc/acpi/ibm/led 778sysfs attributes: as per LED class, see below for names 779 780Some of the LED indicators can be controlled through this feature. On 781some older ThinkPad models, it is possible to query the status of the 782LED indicators as well. Newer ThinkPads cannot query the real status 783of the LED indicators. 784 785Because misuse of the LEDs could induce an unaware user to perform 786dangerous actions (like undocking or ejecting a bay device while the 787buses are still active), or mask an important alarm (such as a nearly 788empty battery, or a broken battery), access to most LEDs is 789restricted. 790 791Unrestricted access to all LEDs requires that thinkpad-acpi be 792compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled. 793Distributions must never enable this option. Individual users that 794are aware of the consequences are welcome to enabling it. 795 796Audio mute and microphone mute LEDs are supported, but currently not 797visible to userspace. They are used by the snd-hda-intel audio driver. 798 799procfs notes 800^^^^^^^^^^^^ 801 802The available commands are:: 803 804 echo '<LED number> on' >/proc/acpi/ibm/led 805 echo '<LED number> off' >/proc/acpi/ibm/led 806 echo '<LED number> blink' >/proc/acpi/ibm/led 807 808The <LED number> range is 0 to 15. The set of LEDs that can be 809controlled varies from model to model. Here is the common ThinkPad 810mapping: 811 812 - 0 - power 813 - 1 - battery (orange) 814 - 2 - battery (green) 815 - 3 - UltraBase/dock 816 - 4 - UltraBay 817 - 5 - UltraBase battery slot 818 - 6 - (unknown) 819 - 7 - standby 820 - 8 - dock status 1 821 - 9 - dock status 2 822 - 10, 11 - (unknown) 823 - 12 - thinkvantage 824 - 13, 14, 15 - (unknown) 825 826All of the above can be turned on and off and can be made to blink. 827 828sysfs notes 829^^^^^^^^^^^ 830 831The ThinkPad LED sysfs interface is described in detail by the LED class 832documentation, in Documentation/leds/leds-class.rst. 833 834The LEDs are named (in LED ID order, from 0 to 12): 835"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt", 836"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt", 837"tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1", 838"tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3", 839"tpacpi::thinkvantage". 840 841Due to limitations in the sysfs LED class, if the status of the LED 842indicators cannot be read due to an error, thinkpad-acpi will report it as 843a brightness of zero (same as LED off). 844 845If the thinkpad firmware doesn't support reading the current status, 846trying to read the current LED brightness will just return whatever 847brightness was last written to that attribute. 848 849These LEDs can blink using hardware acceleration. To request that a 850ThinkPad indicator LED should blink in hardware accelerated mode, use the 851"timer" trigger, and leave the delay_on and delay_off parameters set to 852zero (to request hardware acceleration autodetection). 853 854LEDs that are known not to exist in a given ThinkPad model are not 855made available through the sysfs interface. If you have a dock and you 856notice there are LEDs listed for your ThinkPad that do not exist (and 857are not in the dock), or if you notice that there are missing LEDs, 858a report to ibm-acpi-devel@lists.sourceforge.net is appreciated. 859 860 861ACPI sounds -- /proc/acpi/ibm/beep 862---------------------------------- 863 864The BEEP method is used internally by the ACPI firmware to provide 865audible alerts in various situations. This feature allows the same 866sounds to be triggered manually. 867 868The commands are non-negative integer numbers:: 869 870 echo <number> >/proc/acpi/ibm/beep 871 872The valid <number> range is 0 to 17. Not all numbers trigger sounds 873and the sounds vary from model to model. Here is the behavior on the 874X40: 875 876 - 0 - stop a sound in progress (but use 17 to stop 16) 877 - 2 - two beeps, pause, third beep ("low battery") 878 - 3 - single beep 879 - 4 - high, followed by low-pitched beep ("unable") 880 - 5 - single beep 881 - 6 - very high, followed by high-pitched beep ("AC/DC") 882 - 7 - high-pitched beep 883 - 9 - three short beeps 884 - 10 - very long beep 885 - 12 - low-pitched beep 886 - 15 - three high-pitched beeps repeating constantly, stop with 0 887 - 16 - one medium-pitched beep repeating constantly, stop with 17 888 - 17 - stop 16 889 890 891Temperature sensors 892------------------- 893 894procfs: /proc/acpi/ibm/thermal 895 896sysfs device attributes: (hwmon "thinkpad") temp*_input 897 898Most ThinkPads include six or more separate temperature sensors but only 899expose the CPU temperature through the standard ACPI methods. This 900feature shows readings from up to eight different sensors on older 901ThinkPads, and up to sixteen different sensors on newer ThinkPads. 902 903For example, on the X40, a typical output may be: 904 905temperatures: 906 42 42 45 41 36 -128 33 -128 907 908On the T43/p, a typical output may be: 909 910temperatures: 911 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128 912 913The mapping of thermal sensors to physical locations varies depending on 914system-board model (and thus, on ThinkPad model). 915 916https://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that 917tries to track down these locations for various models. 918 919Most (newer?) models seem to follow this pattern: 920 921- 1: CPU 922- 2: (depends on model) 923- 3: (depends on model) 924- 4: GPU 925- 5: Main battery: main sensor 926- 6: Bay battery: main sensor 927- 7: Main battery: secondary sensor 928- 8: Bay battery: secondary sensor 929- 9-15: (depends on model) 930 931For the R51 (source: Thomas Gruber): 932 933- 2: Mini-PCI 934- 3: Internal HDD 935 936For the T43, T43/p (source: Shmidoax/Thinkwiki.org) 937https://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p 938 939- 2: System board, left side (near PCMCIA slot), reported as HDAPS temp 940- 3: PCMCIA slot 941- 9: MCH (northbridge) to DRAM Bus 942- 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI 943 card, under touchpad 944- 11: Power regulator, underside of system board, below F2 key 945 946The A31 has a very atypical layout for the thermal sensors 947(source: Milos Popovic, https://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31) 948 949- 1: CPU 950- 2: Main Battery: main sensor 951- 3: Power Converter 952- 4: Bay Battery: main sensor 953- 5: MCH (northbridge) 954- 6: PCMCIA/ambient 955- 7: Main Battery: secondary sensor 956- 8: Bay Battery: secondary sensor 957 958 959Procfs notes 960^^^^^^^^^^^^ 961 962 Readings from sensors that are not available return -128. 963 No commands can be written to this file. 964 965Sysfs notes 966^^^^^^^^^^^ 967 968 Sensors that are not available return the ENXIO error. This 969 status may change at runtime, as there are hotplug thermal 970 sensors, like those inside the batteries and docks. 971 972 thinkpad-acpi thermal sensors are reported through the hwmon 973 subsystem, and follow all of the hwmon guidelines at 974 Documentation/hwmon. 975 976EXPERIMENTAL: Embedded controller register dump 977----------------------------------------------- 978 979This feature is not included in the thinkpad driver anymore. 980Instead the EC can be accessed through /sys/kernel/debug/ec with 981a userspace tool which can be found here: 982ftp://ftp.suse.com/pub/people/trenn/sources/ec 983 984Use it to determine the register holding the fan 985speed on some models. To do that, do the following: 986 987 - make sure the battery is fully charged 988 - make sure the fan is running 989 - use above mentioned tool to read out the EC 990 991Often fan and temperature values vary between 992readings. Since temperatures don't change vary fast, you can take 993several quick dumps to eliminate them. 994 995You can use a similar method to figure out the meaning of other 996embedded controller registers - e.g. make sure nothing else changes 997except the charging or discharging battery to determine which 998registers contain the current battery capacity, etc. If you experiment 999with this, do send me your results (including some complete dumps with 1000a description of the conditions when they were taken.) 1001 1002 1003LCD brightness control 1004---------------------- 1005 1006procfs: /proc/acpi/ibm/brightness 1007 1008sysfs backlight device "thinkpad_screen" 1009 1010This feature allows software control of the LCD brightness on ThinkPad 1011models which don't have a hardware brightness slider. 1012 1013It has some limitations: the LCD backlight cannot be actually turned 1014on or off by this interface, it just controls the backlight brightness 1015level. 1016 1017On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control 1018has eight brightness levels, ranging from 0 to 7. Some of the levels 1019may not be distinct. Later Lenovo models that implement the ACPI 1020display backlight brightness control methods have 16 levels, ranging 1021from 0 to 15. 1022 1023For IBM ThinkPads, there are two interfaces to the firmware for direct 1024brightness control, EC and UCMS (or CMOS). To select which one should be 1025used, use the brightness_mode module parameter: brightness_mode=1 selects 1026EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC 1027mode with NVRAM backing (so that brightness changes are remembered across 1028shutdown/reboot). 1029 1030The driver tries to select which interface to use from a table of 1031defaults for each ThinkPad model. If it makes a wrong choice, please 1032report this as a bug, so that we can fix it. 1033 1034Lenovo ThinkPads only support brightness_mode=2 (UCMS). 1035 1036When display backlight brightness controls are available through the 1037standard ACPI interface, it is best to use it instead of this direct 1038ThinkPad-specific interface. The driver will disable its native 1039backlight brightness control interface if it detects that the standard 1040ACPI interface is available in the ThinkPad. 1041 1042If you want to use the thinkpad-acpi backlight brightness control 1043instead of the generic ACPI video backlight brightness control for some 1044reason, you should use the acpi_backlight=vendor kernel parameter. 1045 1046The brightness_enable module parameter can be used to control whether 1047the LCD brightness control feature will be enabled when available. 1048brightness_enable=0 forces it to be disabled. brightness_enable=1 1049forces it to be enabled when available, even if the standard ACPI 1050interface is also available. 1051 1052Procfs notes 1053^^^^^^^^^^^^ 1054 1055The available commands are:: 1056 1057 echo up >/proc/acpi/ibm/brightness 1058 echo down >/proc/acpi/ibm/brightness 1059 echo 'level <level>' >/proc/acpi/ibm/brightness 1060 1061Sysfs notes 1062^^^^^^^^^^^ 1063 1064The interface is implemented through the backlight sysfs class, which is 1065poorly documented at this time. 1066 1067Locate the thinkpad_screen device under /sys/class/backlight, and inside 1068it there will be the following attributes: 1069 1070 max_brightness: 1071 Reads the maximum brightness the hardware can be set to. 1072 The minimum is always zero. 1073 1074 actual_brightness: 1075 Reads what brightness the screen is set to at this instant. 1076 1077 brightness: 1078 Writes request the driver to change brightness to the 1079 given value. Reads will tell you what brightness the 1080 driver is trying to set the display to when "power" is set 1081 to zero and the display has not been dimmed by a kernel 1082 power management event. 1083 1084 power: 1085 power management mode, where 0 is "display on", and 1 to 3 1086 will dim the display backlight to brightness level 0 1087 because thinkpad-acpi cannot really turn the backlight 1088 off. Kernel power management events can temporarily 1089 increase the current power management level, i.e. they can 1090 dim the display. 1091 1092 1093WARNING: 1094 1095 Whatever you do, do NOT ever call thinkpad-acpi backlight-level change 1096 interface and the ACPI-based backlight level change interface 1097 (available on newer BIOSes, and driven by the Linux ACPI video driver) 1098 at the same time. The two will interact in bad ways, do funny things, 1099 and maybe reduce the life of the backlight lamps by needlessly kicking 1100 its level up and down at every change. 1101 1102 1103Volume control (Console Audio control) 1104-------------------------------------- 1105 1106procfs: /proc/acpi/ibm/volume 1107 1108ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC" 1109 1110NOTE: by default, the volume control interface operates in read-only 1111mode, as it is supposed to be used for on-screen-display purposes. 1112The read/write mode can be enabled through the use of the 1113"volume_control=1" module parameter. 1114 1115NOTE: distros are urged to not enable volume_control by default, this 1116should be done by the local admin only. The ThinkPad UI is for the 1117console audio control to be done through the volume keys only, and for 1118the desktop environment to just provide on-screen-display feedback. 1119Software volume control should be done only in the main AC97/HDA 1120mixer. 1121 1122 1123About the ThinkPad Console Audio control 1124^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1125 1126ThinkPads have a built-in amplifier and muting circuit that drives the 1127console headphone and speakers. This circuit is after the main AC97 1128or HDA mixer in the audio path, and under exclusive control of the 1129firmware. 1130 1131ThinkPads have three special hotkeys to interact with the console 1132audio control: volume up, volume down and mute. 1133 1134It is worth noting that the normal way the mute function works (on 1135ThinkPads that do not have a "mute LED") is: 1136 11371. Press mute to mute. It will *always* mute, you can press it as 1138 many times as you want, and the sound will remain mute. 1139 11402. Press either volume key to unmute the ThinkPad (it will _not_ 1141 change the volume, it will just unmute). 1142 1143This is a very superior design when compared to the cheap software-only 1144mute-toggle solution found on normal consumer laptops: you can be 1145absolutely sure the ThinkPad will not make noise if you press the mute 1146button, no matter the previous state. 1147 1148The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain 1149amplifiers driving the speakers and headphone output, and the firmware 1150also handles volume control for the headphone and speakers on these 1151ThinkPads without any help from the operating system (this volume 1152control stage exists after the main AC97 or HDA mixer in the audio 1153path). 1154 1155The newer Lenovo models only have firmware mute control, and depend on 1156the main HDA mixer to do volume control (which is done by the operating 1157system). In this case, the volume keys are filtered out for unmute 1158key press (there are some firmware bugs in this area) and delivered as 1159normal key presses to the operating system (thinkpad-acpi is not 1160involved). 1161 1162 1163The ThinkPad-ACPI volume control 1164^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1165 1166The preferred way to interact with the Console Audio control is the 1167ALSA interface. 1168 1169The legacy procfs interface allows one to read the current state, 1170and if volume control is enabled, accepts the following commands:: 1171 1172 echo up >/proc/acpi/ibm/volume 1173 echo down >/proc/acpi/ibm/volume 1174 echo mute >/proc/acpi/ibm/volume 1175 echo unmute >/proc/acpi/ibm/volume 1176 echo 'level <level>' >/proc/acpi/ibm/volume 1177 1178The <level> number range is 0 to 14 although not all of them may be 1179distinct. To unmute the volume after the mute command, use either the 1180up or down command (the level command will not unmute the volume), or 1181the unmute command. 1182 1183You can use the volume_capabilities parameter to tell the driver 1184whether your thinkpad has volume control or mute-only control: 1185volume_capabilities=1 for mixers with mute and volume control, 1186volume_capabilities=2 for mixers with only mute control. 1187 1188If the driver misdetects the capabilities for your ThinkPad model, 1189please report this to ibm-acpi-devel@lists.sourceforge.net, so that we 1190can update the driver. 1191 1192There are two strategies for volume control. To select which one 1193should be used, use the volume_mode module parameter: volume_mode=1 1194selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing 1195(so that volume/mute changes are remembered across shutdown/reboot). 1196 1197The driver will operate in volume_mode=3 by default. If that does not 1198work well on your ThinkPad model, please report this to 1199ibm-acpi-devel@lists.sourceforge.net. 1200 1201The driver supports the standard ALSA module parameters. If the ALSA 1202mixer is disabled, the driver will disable all volume functionality. 1203 1204 1205Fan control and monitoring: fan speed, fan enable/disable 1206--------------------------------------------------------- 1207 1208procfs: /proc/acpi/ibm/fan 1209 1210sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1, pwm1_enable, fan2_input 1211 1212sysfs hwmon driver attributes: fan_watchdog 1213 1214NOTE NOTE NOTE: 1215 fan control operations are disabled by default for 1216 safety reasons. To enable them, the module parameter "fan_control=1" 1217 must be given to thinkpad-acpi. 1218 1219This feature attempts to show the current fan speed, control mode and 1220other fan data that might be available. The speed is read directly 1221from the hardware registers of the embedded controller. This is known 1222to work on later R, T, X and Z series ThinkPads but may show a bogus 1223value on other models. 1224 1225Some Lenovo ThinkPads support a secondary fan. This fan cannot be 1226controlled separately, it shares the main fan control. 1227 1228Fan levels 1229^^^^^^^^^^ 1230 1231Most ThinkPad fans work in "levels" at the firmware interface. Level 0 1232stops the fan. The higher the level, the higher the fan speed, although 1233adjacent levels often map to the same fan speed. 7 is the highest 1234level, where the fan reaches the maximum recommended speed. 1235 1236Level "auto" means the EC changes the fan level according to some 1237internal algorithm, usually based on readings from the thermal sensors. 1238 1239There is also a "full-speed" level, also known as "disengaged" level. 1240In this level, the EC disables the speed-locked closed-loop fan control, 1241and drives the fan as fast as it can go, which might exceed hardware 1242limits, so use this level with caution. 1243 1244The fan usually ramps up or down slowly from one speed to another, and 1245it is normal for the EC to take several seconds to react to fan 1246commands. The full-speed level may take up to two minutes to ramp up to 1247maximum speed, and in some ThinkPads, the tachometer readings go stale 1248while the EC is transitioning to the full-speed level. 1249 1250WARNING WARNING WARNING: do not leave the fan disabled unless you are 1251monitoring all of the temperature sensor readings and you are ready to 1252enable it if necessary to avoid overheating. 1253 1254An enabled fan in level "auto" may stop spinning if the EC decides the 1255ThinkPad is cool enough and doesn't need the extra airflow. This is 1256normal, and the EC will spin the fan up if the various thermal readings 1257rise too much. 1258 1259On the X40, this seems to depend on the CPU and HDD temperatures. 1260Specifically, the fan is turned on when either the CPU temperature 1261climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The 1262fan is turned off when the CPU temperature drops to 49 degrees and the 1263HDD temperature drops to 41 degrees. These thresholds cannot 1264currently be controlled. 1265 1266The ThinkPad's ACPI DSDT code will reprogram the fan on its own when 1267certain conditions are met. It will override any fan programming done 1268through thinkpad-acpi. 1269 1270The thinkpad-acpi kernel driver can be programmed to revert the fan 1271level to a safe setting if userspace does not issue one of the procfs 1272fan commands: "enable", "disable", "level" or "watchdog", or if there 1273are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is 1274set to 1, manual mode) within a configurable amount of time of up to 1275120 seconds. This functionality is called fan safety watchdog. 1276 1277Note that the watchdog timer stops after it enables the fan. It will be 1278rearmed again automatically (using the same interval) when one of the 1279above mentioned fan commands is received. The fan watchdog is, 1280therefore, not suitable to protect against fan mode changes made through 1281means other than the "enable", "disable", and "level" procfs fan 1282commands, or the hwmon fan control sysfs interface. 1283 1284Procfs notes 1285^^^^^^^^^^^^ 1286 1287The fan may be enabled or disabled with the following commands:: 1288 1289 echo enable >/proc/acpi/ibm/fan 1290 echo disable >/proc/acpi/ibm/fan 1291 1292Placing a fan on level 0 is the same as disabling it. Enabling a fan 1293will try to place it in a safe level if it is too slow or disabled. 1294 1295The fan level can be controlled with the command:: 1296 1297 echo 'level <level>' > /proc/acpi/ibm/fan 1298 1299Where <level> is an integer from 0 to 7, or one of the words "auto" or 1300"full-speed" (without the quotes). Not all ThinkPads support the "auto" 1301and "full-speed" levels. The driver accepts "disengaged" as an alias for 1302"full-speed", and reports it as "disengaged" for backwards 1303compatibility. 1304 1305On the X31 and X40 (and ONLY on those models), the fan speed can be 1306controlled to a certain degree. Once the fan is running, it can be 1307forced to run faster or slower with the following command:: 1308 1309 echo 'speed <speed>' > /proc/acpi/ibm/fan 1310 1311The sustainable range of fan speeds on the X40 appears to be from about 13123700 to about 7350. Values outside this range either do not have any 1313effect or the fan speed eventually settles somewhere in that range. The 1314fan cannot be stopped or started with this command. This functionality 1315is incomplete, and not available through the sysfs interface. 1316 1317To program the safety watchdog, use the "watchdog" command:: 1318 1319 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan 1320 1321If you want to disable the watchdog, use 0 as the interval. 1322 1323Sysfs notes 1324^^^^^^^^^^^ 1325 1326The sysfs interface follows the hwmon subsystem guidelines for the most 1327part, and the exception is the fan safety watchdog. 1328 1329Writes to any of the sysfs attributes may return the EINVAL error if 1330that operation is not supported in a given ThinkPad or if the parameter 1331is out-of-bounds, and EPERM if it is forbidden. They may also return 1332EINTR (interrupted system call), and EIO (I/O error while trying to talk 1333to the firmware). 1334 1335Features not yet implemented by the driver return ENOSYS. 1336 1337hwmon device attribute pwm1_enable: 1338 - 0: PWM offline (fan is set to full-speed mode) 1339 - 1: Manual PWM control (use pwm1 to set fan level) 1340 - 2: Hardware PWM control (EC "auto" mode) 1341 - 3: reserved (Software PWM control, not implemented yet) 1342 1343 Modes 0 and 2 are not supported by all ThinkPads, and the 1344 driver is not always able to detect this. If it does know a 1345 mode is unsupported, it will return -EINVAL. 1346 1347hwmon device attribute pwm1: 1348 Fan level, scaled from the firmware values of 0-7 to the hwmon 1349 scale of 0-255. 0 means fan stopped, 255 means highest normal 1350 speed (level 7). 1351 1352 This attribute only commands the fan if pmw1_enable is set to 1 1353 (manual PWM control). 1354 1355hwmon device attribute fan1_input: 1356 Fan tachometer reading, in RPM. May go stale on certain 1357 ThinkPads while the EC transitions the PWM to offline mode, 1358 which can take up to two minutes. May return rubbish on older 1359 ThinkPads. 1360 1361hwmon device attribute fan2_input: 1362 Fan tachometer reading, in RPM, for the secondary fan. 1363 Available only on some ThinkPads. If the secondary fan is 1364 not installed, will always read 0. 1365 1366hwmon driver attribute fan_watchdog: 1367 Fan safety watchdog timer interval, in seconds. Minimum is 1368 1 second, maximum is 120 seconds. 0 disables the watchdog. 1369 1370To stop the fan: set pwm1 to zero, and pwm1_enable to 1. 1371 1372To start the fan in a safe mode: set pwm1_enable to 2. If that fails 1373with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255 1374would be the safest choice, though). 1375 1376 1377WAN 1378--- 1379 1380procfs: /proc/acpi/ibm/wan 1381 1382sysfs device attribute: wwan_enable (deprecated) 1383 1384sysfs rfkill class: switch "tpacpi_wwan_sw" 1385 1386This feature shows the presence and current state of the built-in 1387Wireless WAN device. 1388 1389If the ThinkPad supports it, the WWAN state is stored in NVRAM, 1390so it is kept across reboots and power-off. 1391 1392It was tested on a Lenovo ThinkPad X60. It should probably work on other 1393ThinkPad models which come with this module installed. 1394 1395Procfs notes 1396^^^^^^^^^^^^ 1397 1398If the W-WAN card is installed, the following commands can be used:: 1399 1400 echo enable > /proc/acpi/ibm/wan 1401 echo disable > /proc/acpi/ibm/wan 1402 1403Sysfs notes 1404^^^^^^^^^^^ 1405 1406 If the W-WAN card is installed, it can be enabled / 1407 disabled through the "wwan_enable" thinkpad-acpi device 1408 attribute, and its current status can also be queried. 1409 1410 enable: 1411 - 0: disables WWAN card / WWAN card is disabled 1412 - 1: enables WWAN card / WWAN card is enabled. 1413 1414 Note: this interface has been superseded by the generic rfkill 1415 class. It has been deprecated, and it will be removed in year 1416 2010. 1417 1418 rfkill controller switch "tpacpi_wwan_sw": refer to 1419 Documentation/driver-api/rfkill.rst for details. 1420 1421 1422LCD Shadow control 1423------------------ 1424 1425procfs: /proc/acpi/ibm/lcdshadow 1426 1427Some newer T480s and T490s ThinkPads provide a feature called 1428PrivacyGuard. By turning this feature on, the usable vertical and 1429horizontal viewing angles of the LCD can be limited (as if some privacy 1430screen was applied manually in front of the display). 1431 1432procfs notes 1433^^^^^^^^^^^^ 1434 1435The available commands are:: 1436 1437 echo '0' >/proc/acpi/ibm/lcdshadow 1438 echo '1' >/proc/acpi/ibm/lcdshadow 1439 1440The first command ensures the best viewing angle and the latter one turns 1441on the feature, restricting the viewing angles. 1442 1443 1444DYTC Lapmode sensor 1445------------------- 1446 1447sysfs: dytc_lapmode 1448 1449Newer thinkpads and mobile workstations have the ability to determine if 1450the device is in deskmode or lapmode. This feature is used by user space 1451to decide if WWAN transmission can be increased to maximum power and is 1452also useful for understanding the different thermal modes available as 1453they differ between desk and lap mode. 1454 1455The property is read-only. If the platform doesn't have support the sysfs 1456class is not created. 1457 1458EXPERIMENTAL: UWB 1459----------------- 1460 1461This feature is considered EXPERIMENTAL because it has not been extensively 1462tested and validated in various ThinkPad models yet. The feature may not 1463work as expected. USE WITH CAUTION! To use this feature, you need to supply 1464the experimental=1 parameter when loading the module. 1465 1466sysfs rfkill class: switch "tpacpi_uwb_sw" 1467 1468This feature exports an rfkill controller for the UWB device, if one is 1469present and enabled in the BIOS. 1470 1471Sysfs notes 1472^^^^^^^^^^^ 1473 1474 rfkill controller switch "tpacpi_uwb_sw": refer to 1475 Documentation/driver-api/rfkill.rst for details. 1476 1477 1478Setting keyboard language 1479------------------------- 1480 1481sysfs: keyboard_lang 1482 1483This feature is used to set keyboard language to ECFW using ASL interface. 1484Fewer thinkpads models like T580 , T590 , T15 Gen 1 etc.. has "=", "(', 1485")" numeric keys, which are not displaying correctly, when keyboard language 1486is other than "english". This is because the default keyboard language in ECFW 1487is set as "english". Hence using this sysfs, user can set the correct keyboard 1488language to ECFW and then these key's will work correctly. 1489 1490Example of command to set keyboard language is mentioned below:: 1491 1492 echo jp > /sys/devices/platform/thinkpad_acpi/keyboard_lang 1493 1494Text corresponding to keyboard layout to be set in sysfs are: be(Belgian), 1495cz(Czech), da(Danish), de(German), en(English), es(Spain), et(Estonian), 1496fr(French), fr-ch(French(Switzerland)), hu(Hungarian), it(Italy), jp (Japan), 1497nl(Dutch), nn(Norway), pl(Polish), pt(portuguese), sl(Slovenian), sv(Sweden), 1498tr(Turkey) 1499 1500WWAN Antenna type 1501----------------- 1502 1503sysfs: wwan_antenna_type 1504 1505On some newer Thinkpads we need to set SAR value based on the antenna 1506type. This interface will be used by userspace to get the antenna type 1507and set the corresponding SAR value, as is required for FCC certification. 1508 1509The available commands are:: 1510 1511 cat /sys/devices/platform/thinkpad_acpi/wwan_antenna_type 1512 1513Currently 2 antenna types are supported as mentioned below: 1514- type a 1515- type b 1516 1517The property is read-only. If the platform doesn't have support the sysfs 1518class is not created. 1519 1520Auxmac 1521------ 1522 1523sysfs: auxmac 1524 1525Some newer Thinkpads have a feature called MAC Address Pass-through. This 1526feature is implemented by the system firmware to provide a system unique MAC, 1527that can override a dock or USB ethernet dongle MAC, when connected to a 1528network. This property enables user-space to easily determine the MAC address 1529if the feature is enabled. 1530 1531The values of this auxiliary MAC are: 1532 1533 cat /sys/devices/platform/thinkpad_acpi/auxmac 1534 1535If the feature is disabled, the value will be 'disabled'. 1536 1537This property is read-only. 1538 1539Adaptive keyboard 1540----------------- 1541 1542sysfs device attribute: adaptive_kbd_mode 1543 1544This sysfs attribute controls the keyboard "face" that will be shown on the 1545Lenovo X1 Carbon 2nd gen (2014)'s adaptive keyboard. The value can be read 1546and set. 1547 1548- 0 = Home mode 1549- 1 = Web-browser mode 1550- 2 = Web-conference mode 1551- 3 = Function mode 1552- 4 = Layflat mode 1553 1554For more details about which buttons will appear depending on the mode, please 1555review the laptop's user guide: 1556https://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles_pdf/x1carbon_2_ug_en.pdf 1557 1558Battery charge control 1559---------------------- 1560 1561sysfs attributes: 1562/sys/class/power_supply/BAT*/charge_control_{start,end}_threshold 1563 1564These two attributes are created for those batteries that are supported by the 1565driver. They enable the user to control the battery charge thresholds of the 1566given battery. Both values may be read and set. `charge_control_start_threshold` 1567accepts an integer between 0 and 99 (inclusive); this value represents a battery 1568percentage level, below which charging will begin. `charge_control_end_threshold` 1569accepts an integer between 1 and 100 (inclusive); this value represents a battery 1570percentage level, above which charging will stop. 1571 1572The exact semantics of the attributes may be found in 1573Documentation/ABI/testing/sysfs-class-power. 1574 1575Multiple Commands, Module Parameters 1576------------------------------------ 1577 1578Multiple commands can be written to the proc files in one shot by 1579separating them with commas, for example:: 1580 1581 echo enable,0xffff > /proc/acpi/ibm/hotkey 1582 echo lcd_disable,crt_enable > /proc/acpi/ibm/video 1583 1584Commands can also be specified when loading the thinkpad-acpi module, 1585for example:: 1586 1587 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable 1588 1589 1590Enabling debugging output 1591------------------------- 1592 1593The module takes a debug parameter which can be used to selectively 1594enable various classes of debugging output, for example:: 1595 1596 modprobe thinkpad_acpi debug=0xffff 1597 1598will enable all debugging output classes. It takes a bitmask, so 1599to enable more than one output class, just add their values. 1600 1601 ============= ====================================== 1602 Debug bitmask Description 1603 ============= ====================================== 1604 0x8000 Disclose PID of userspace programs 1605 accessing some functions of the driver 1606 0x0001 Initialization and probing 1607 0x0002 Removal 1608 0x0004 RF Transmitter control (RFKILL) 1609 (bluetooth, WWAN, UWB...) 1610 0x0008 HKEY event interface, hotkeys 1611 0x0010 Fan control 1612 0x0020 Backlight brightness 1613 0x0040 Audio mixer/volume control 1614 ============= ====================================== 1615 1616There is also a kernel build option to enable more debugging 1617information, which may be necessary to debug driver problems. 1618 1619The level of debugging information output by the driver can be changed 1620at runtime through sysfs, using the driver attribute debug_level. The 1621attribute takes the same bitmask as the debug module parameter above. 1622 1623 1624Force loading of module 1625----------------------- 1626 1627If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify 1628the module parameter force_load=1. Regardless of whether this works or 1629not, please contact ibm-acpi-devel@lists.sourceforge.net with a report. 1630 1631 1632Sysfs interface changelog 1633^^^^^^^^^^^^^^^^^^^^^^^^^ 1634 1635========= =============================================================== 16360x000100: Initial sysfs support, as a single platform driver and 1637 device. 16380x000200: Hot key support for 32 hot keys, and radio slider switch 1639 support. 16400x010000: Hot keys are now handled by default over the input 1641 layer, the radio switch generates input event EV_RADIO, 1642 and the driver enables hot key handling by default in 1643 the firmware. 1644 16450x020000: ABI fix: added a separate hwmon platform device and 1646 driver, which must be located by name (thinkpad) 1647 and the hwmon class for libsensors4 (lm-sensors 3) 1648 compatibility. Moved all hwmon attributes to this 1649 new platform device. 1650 16510x020100: Marker for thinkpad-acpi with hot key NVRAM polling 1652 support. If you must, use it to know you should not 1653 start a userspace NVRAM poller (allows to detect when 1654 NVRAM is compiled out by the user because it is 1655 unneeded/undesired in the first place). 16560x020101: Marker for thinkpad-acpi with hot key NVRAM polling 1657 and proper hotkey_mask semantics (version 8 of the 1658 NVRAM polling patch). Some development snapshots of 1659 0.18 had an earlier version that did strange things 1660 to hotkey_mask. 1661 16620x020200: Add poll()/select() support to the following attributes: 1663 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason 1664 16650x020300: hotkey enable/disable support removed, attributes 1666 hotkey_bios_enabled and hotkey_enable deprecated and 1667 marked for removal. 1668 16690x020400: Marker for 16 LEDs support. Also, LEDs that are known 1670 to not exist in a given model are not registered with 1671 the LED sysfs class anymore. 1672 16730x020500: Updated hotkey driver, hotkey_mask is always available 1674 and it is always able to disable hot keys. Very old 1675 thinkpads are properly supported. hotkey_bios_mask 1676 is deprecated and marked for removal. 1677 16780x020600: Marker for backlight change event support. 1679 16800x020700: Support for mute-only mixers. 1681 Volume control in read-only mode by default. 1682 Marker for ALSA mixer support. 1683 16840x030000: Thermal and fan sysfs attributes were moved to the hwmon 1685 device instead of being attached to the backing platform 1686 device. 1687========= =============================================================== 1688