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 2024 platforms replaced by 449 0x131f (see below) and on newer 450 platforms (2025 +) keycode is 451 replaced by 0x1401 (see below). 452 4530x1009 0x08 FN+F9 - 454 455... ... ... ... 456 4570x100B 0x0A FN+F11 - 458 4590x100C 0x0B FN+F12 Sleep to disk. You are always 460 supposed to handle it yourself, 461 either through the ACPI event, 462 or through a hotkey event. 463 The firmware may refuse to 464 generate further FN+F12 key 465 press events until a S3 or S4 466 ACPI sleep cycle is performed, 467 or some time passes. 468 4690x100D 0x0C FN+BACKSPACE - 4700x100E 0x0D FN+INSERT - 4710x100F 0x0E FN+DELETE - 472 4730x1010 0x0F FN+HOME Brightness up. This key is 474 always handled by the firmware 475 in IBM ThinkPads, even when 476 unmasked. Just leave it alone. 477 For Lenovo ThinkPads with a new 478 BIOS, it has to be handled either 479 by the ACPI OSI, or by userspace. 480 The driver does the right thing, 481 never mess with this. 4820x1011 0x10 FN+END Brightness down. See brightness 483 up for details. 484 4850x1012 0x11 FN+PGUP ThinkLight toggle. This key is 486 always handled by the firmware, 487 even when unmasked. 488 4890x1013 0x12 FN+PGDOWN - 490 4910x1014 0x13 FN+SPACE Zoom key 492 4930x1015 0x14 VOLUME UP Internal mixer volume up. This 494 key is always handled by the 495 firmware, even when unmasked. 496 NOTE: Lenovo seems to be changing 497 this. 4980x1016 0x15 VOLUME DOWN Internal mixer volume up. This 499 key is always handled by the 500 firmware, even when unmasked. 501 NOTE: Lenovo seems to be changing 502 this. 5030x1017 0x16 MUTE Mute internal mixer. This 504 key is always handled by the 505 firmware, even when unmasked. 506 5070x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key 508 5090x1019 0x18 unknown 510 5110x131f ... FN+F8 Platform Mode change (2024 systems). 512 Implemented in driver. 513 5140x1401 ... FN+F8 Platform Mode change (2025 + systems). 515 Implemented in driver. 516... ... ... 517 5180x1020 0x1F unknown 519======= ======= ============== ============================================== 520 521The ThinkPad firmware does not allow one to differentiate when most hot 522keys are pressed or released (either that, or we don't know how to, yet). 523For these keys, the driver generates a set of events for a key press and 524immediately issues the same set of events for a key release. It is 525unknown by the driver if the ThinkPad firmware triggered these events on 526hot key press or release, but the firmware will do it for either one, not 527both. 528 529If a key is mapped to KEY_RESERVED, it generates no input events at all. 530If a key is mapped to KEY_UNKNOWN, it generates an input event that 531includes an scan code. If a key is mapped to anything else, it will 532generate input device EV_KEY events. 533 534In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW 535events for switches: 536 537============== ============================================== 538SW_RFKILL_ALL T60 and later hardware rfkill rocker switch 539SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A 540============== ============================================== 541 542Non hotkey ACPI HKEY event map 543------------------------------ 544 545Events that are never propagated by the driver: 546 547====== ================================================== 5480x2304 System is waking up from suspend to undock 5490x2305 System is waking up from suspend to eject bay 5500x2404 System is waking up from hibernation to undock 5510x2405 System is waking up from hibernation to eject bay 5520x5001 Lid closed 5530x5002 Lid opened 5540x5009 Tablet swivel: switched to tablet mode 5550x500A Tablet swivel: switched to normal mode 5560x5010 Brightness level changed/control event 5570x6000 KEYBOARD: Numlock key pressed 5580x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED) 5590x7000 Radio Switch may have changed state 560====== ================================================== 561 562 563Events that are propagated by the driver to userspace: 564 565====== ===================================================== 5660x2313 ALARM: System is waking up from suspend because 567 the battery is nearly empty 5680x2413 ALARM: System is waking up from hibernation because 569 the battery is nearly empty 5700x3003 Bay ejection (see 0x2x05) complete, can sleep again 5710x3006 Bay hotplug request (hint to power up SATA link when 572 the optical drive tray is ejected) 5730x4003 Undocked (see 0x2x04), can sleep again 5740x4010 Docked into hotplug port replicator (non-ACPI dock) 5750x4011 Undocked from hotplug port replicator (non-ACPI dock) 5760x500B Tablet pen inserted into its storage bay 5770x500C Tablet pen removed from its storage bay 5780x6011 ALARM: battery is too hot 5790x6012 ALARM: battery is extremely hot 5800x6021 ALARM: a sensor is too hot 5810x6022 ALARM: a sensor is extremely hot 5820x6030 System thermal table changed 5830x6032 Thermal Control command set completion (DYTC, Windows) 5840x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED) 5850x60C0 X1 Yoga 2016, Tablet mode status changed 5860x60F0 Thermal Transformation changed (GMTS, Windows) 587====== ===================================================== 588 589Battery nearly empty alarms are a last resort attempt to get the 590operating system to hibernate or shutdown cleanly (0x2313), or shutdown 591cleanly (0x2413) before power is lost. They must be acted upon, as the 592wake up caused by the firmware will have negated most safety nets... 593 594When any of the "too hot" alarms happen, according to Lenovo the user 595should suspend or hibernate the laptop (and in the case of battery 596alarms, unplug the AC adapter) to let it cool down. These alarms do 597signal that something is wrong, they should never happen on normal 598operating conditions. 599 600The "extremely hot" alarms are emergencies. According to Lenovo, the 601operating system is to force either an immediate suspend or hibernate 602cycle, or a system shutdown. Obviously, something is very wrong if this 603happens. 604 605 606Brightness hotkey notes 607^^^^^^^^^^^^^^^^^^^^^^^ 608 609Don't mess with the brightness hotkeys in a Thinkpad. If you want 610notifications for OSD, use the sysfs backlight class event support. 611 612The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events 613automatically for the cases were userspace has to do something to 614implement brightness changes. When you override these events, you will 615either fail to handle properly the ThinkPads that require explicit 616action to change backlight brightness, or the ThinkPads that require 617that no action be taken to work properly. 618 619 620Bluetooth 621--------- 622 623procfs: /proc/acpi/ibm/bluetooth 624 625sysfs device attribute: bluetooth_enable (deprecated) 626 627sysfs rfkill class: switch "tpacpi_bluetooth_sw" 628 629This feature shows the presence and current state of a ThinkPad 630Bluetooth device in the internal ThinkPad CDC slot. 631 632If the ThinkPad supports it, the Bluetooth state is stored in NVRAM, 633so it is kept across reboots and power-off. 634 635Procfs notes 636^^^^^^^^^^^^ 637 638If Bluetooth is installed, the following commands can be used:: 639 640 echo enable > /proc/acpi/ibm/bluetooth 641 echo disable > /proc/acpi/ibm/bluetooth 642 643Sysfs notes 644^^^^^^^^^^^ 645 646 If the Bluetooth CDC card is installed, it can be enabled / 647 disabled through the "bluetooth_enable" thinkpad-acpi device 648 attribute, and its current status can also be queried. 649 650 enable: 651 652 - 0: disables Bluetooth / Bluetooth is disabled 653 - 1: enables Bluetooth / Bluetooth is enabled. 654 655 Note: this interface has been superseded by the generic rfkill 656 class. It has been deprecated, and it will be removed in year 657 2010. 658 659 rfkill controller switch "tpacpi_bluetooth_sw": refer to 660 Documentation/driver-api/rfkill.rst for details. 661 662 663Video output control -- /proc/acpi/ibm/video 664-------------------------------------------- 665 666This feature allows control over the devices used for video output - 667LCD, CRT or DVI (if available). The following commands are available:: 668 669 echo lcd_enable > /proc/acpi/ibm/video 670 echo lcd_disable > /proc/acpi/ibm/video 671 echo crt_enable > /proc/acpi/ibm/video 672 echo crt_disable > /proc/acpi/ibm/video 673 echo dvi_enable > /proc/acpi/ibm/video 674 echo dvi_disable > /proc/acpi/ibm/video 675 echo auto_enable > /proc/acpi/ibm/video 676 echo auto_disable > /proc/acpi/ibm/video 677 echo expand_toggle > /proc/acpi/ibm/video 678 echo video_switch > /proc/acpi/ibm/video 679 680NOTE: 681 Access to this feature is restricted to processes owning the 682 CAP_SYS_ADMIN capability for safety reasons, as it can interact badly 683 enough with some versions of X.org to crash it. 684 685Each video output device can be enabled or disabled individually. 686Reading /proc/acpi/ibm/video shows the status of each device. 687 688Automatic video switching can be enabled or disabled. When automatic 689video switching is enabled, certain events (e.g. opening the lid, 690docking or undocking) cause the video output device to change 691automatically. While this can be useful, it also causes flickering 692and, on the X40, video corruption. By disabling automatic switching, 693the flickering or video corruption can be avoided. 694 695The video_switch command cycles through the available video outputs 696(it simulates the behavior of Fn-F7). 697 698Video expansion can be toggled through this feature. This controls 699whether the display is expanded to fill the entire LCD screen when a 700mode with less than full resolution is used. Note that the current 701video expansion status cannot be determined through this feature. 702 703Note that on many models (particularly those using Radeon graphics 704chips) the X driver configures the video card in a way which prevents 705Fn-F7 from working. This also disables the video output switching 706features of this driver, as it uses the same ACPI methods as 707Fn-F7. Video switching on the console should still work. 708 709UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000 710 711 712ThinkLight control 713------------------ 714 715procfs: /proc/acpi/ibm/light 716 717sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED 718 719procfs notes 720^^^^^^^^^^^^ 721 722The ThinkLight status can be read and set through the procfs interface. A 723few models which do not make the status available will show the ThinkLight 724status as "unknown". The available commands are:: 725 726 echo on > /proc/acpi/ibm/light 727 echo off > /proc/acpi/ibm/light 728 729sysfs notes 730^^^^^^^^^^^ 731 732The ThinkLight sysfs interface is documented by the LED class 733documentation, in Documentation/leds/leds-class.rst. The ThinkLight LED name 734is "tpacpi::thinklight". 735 736Due to limitations in the sysfs LED class, if the status of the ThinkLight 737cannot be read or if it is unknown, thinkpad-acpi will report it as "off". 738It is impossible to know if the status returned through sysfs is valid. 739 740 741CMOS/UCMS control 742----------------- 743 744procfs: /proc/acpi/ibm/cmos 745 746sysfs device attribute: cmos_command 747 748This feature is mostly used internally by the ACPI firmware to keep the legacy 749CMOS NVRAM bits in sync with the current machine state, and to record this 750state so that the ThinkPad will retain such settings across reboots. 751 752Some of these commands actually perform actions in some ThinkPad models, but 753this is expected to disappear more and more in newer models. As an example, in 754a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for 755real, but commands 0 to 2 don't control the mixer anymore (they have been 756phased out) and just update the NVRAM. 757 758The range of valid cmos command numbers is 0 to 21, but not all have an 759effect and the behavior varies from model to model. Here is the behavior 760on the X40 (tpb is the ThinkPad Buttons utility): 761 762 - 0 - Related to "Volume down" key press 763 - 1 - Related to "Volume up" key press 764 - 2 - Related to "Mute on" key press 765 - 3 - Related to "Access IBM" key press 766 - 4 - Related to "LCD brightness up" key press 767 - 5 - Related to "LCD brightness down" key press 768 - 11 - Related to "toggle screen expansion" key press/function 769 - 12 - Related to "ThinkLight on" 770 - 13 - Related to "ThinkLight off" 771 - 14 - Related to "ThinkLight" key press (toggle ThinkLight) 772 773The cmos command interface is prone to firmware split-brain problems, as 774in newer ThinkPads it is just a compatibility layer. Do not use it, it is 775exported just as a debug tool. 776 777 778LED control 779----------- 780 781procfs: /proc/acpi/ibm/led 782sysfs attributes: as per LED class, see below for names 783 784Some of the LED indicators can be controlled through this feature. On 785some older ThinkPad models, it is possible to query the status of the 786LED indicators as well. Newer ThinkPads cannot query the real status 787of the LED indicators. 788 789Because misuse of the LEDs could induce an unaware user to perform 790dangerous actions (like undocking or ejecting a bay device while the 791buses are still active), or mask an important alarm (such as a nearly 792empty battery, or a broken battery), access to most LEDs is 793restricted. 794 795Unrestricted access to all LEDs requires that thinkpad-acpi be 796compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled. 797Distributions must never enable this option. Individual users that 798are aware of the consequences are welcome to enabling it. 799 800Audio mute and microphone mute LEDs are supported, but currently not 801visible to userspace. They are used by the snd-hda-intel audio driver. 802 803procfs notes 804^^^^^^^^^^^^ 805 806The available commands are:: 807 808 echo '<LED number> on' >/proc/acpi/ibm/led 809 echo '<LED number> off' >/proc/acpi/ibm/led 810 echo '<LED number> blink' >/proc/acpi/ibm/led 811 812The <LED number> range is 0 to 15. The set of LEDs that can be 813controlled varies from model to model. Here is the common ThinkPad 814mapping: 815 816 - 0 - power 817 - 1 - battery (orange) 818 - 2 - battery (green) 819 - 3 - UltraBase/dock 820 - 4 - UltraBay 821 - 5 - UltraBase battery slot 822 - 6 - (unknown) 823 - 7 - standby 824 - 8 - dock status 1 825 - 9 - dock status 2 826 - 10, 11 - (unknown) 827 - 12 - thinkvantage 828 - 13, 14, 15 - (unknown) 829 830All of the above can be turned on and off and can be made to blink. 831 832sysfs notes 833^^^^^^^^^^^ 834 835The ThinkPad LED sysfs interface is described in detail by the LED class 836documentation, in Documentation/leds/leds-class.rst. 837 838The LEDs are named (in LED ID order, from 0 to 12): 839"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt", 840"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt", 841"tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1", 842"tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3", 843"tpacpi::thinkvantage". 844 845Due to limitations in the sysfs LED class, if the status of the LED 846indicators cannot be read due to an error, thinkpad-acpi will report it as 847a brightness of zero (same as LED off). 848 849If the thinkpad firmware doesn't support reading the current status, 850trying to read the current LED brightness will just return whatever 851brightness was last written to that attribute. 852 853These LEDs can blink using hardware acceleration. To request that a 854ThinkPad indicator LED should blink in hardware accelerated mode, use the 855"timer" trigger, and leave the delay_on and delay_off parameters set to 856zero (to request hardware acceleration autodetection). 857 858LEDs that are known not to exist in a given ThinkPad model are not 859made available through the sysfs interface. If you have a dock and you 860notice there are LEDs listed for your ThinkPad that do not exist (and 861are not in the dock), or if you notice that there are missing LEDs, 862a report to ibm-acpi-devel@lists.sourceforge.net is appreciated. 863 864 865ACPI sounds -- /proc/acpi/ibm/beep 866---------------------------------- 867 868The BEEP method is used internally by the ACPI firmware to provide 869audible alerts in various situations. This feature allows the same 870sounds to be triggered manually. 871 872The commands are non-negative integer numbers:: 873 874 echo <number> >/proc/acpi/ibm/beep 875 876The valid <number> range is 0 to 17. Not all numbers trigger sounds 877and the sounds vary from model to model. Here is the behavior on the 878X40: 879 880 - 0 - stop a sound in progress (but use 17 to stop 16) 881 - 2 - two beeps, pause, third beep ("low battery") 882 - 3 - single beep 883 - 4 - high, followed by low-pitched beep ("unable") 884 - 5 - single beep 885 - 6 - very high, followed by high-pitched beep ("AC/DC") 886 - 7 - high-pitched beep 887 - 9 - three short beeps 888 - 10 - very long beep 889 - 12 - low-pitched beep 890 - 15 - three high-pitched beeps repeating constantly, stop with 0 891 - 16 - one medium-pitched beep repeating constantly, stop with 17 892 - 17 - stop 16 893 894 895Temperature sensors 896------------------- 897 898procfs: /proc/acpi/ibm/thermal 899 900sysfs device attributes: (hwmon "thinkpad") temp*_input 901 902Most ThinkPads include six or more separate temperature sensors but only 903expose the CPU temperature through the standard ACPI methods. This 904feature shows readings from up to eight different sensors on older 905ThinkPads, and up to sixteen different sensors on newer ThinkPads. 906 907For example, on the X40, a typical output may be: 908 909temperatures: 910 42 42 45 41 36 -128 33 -128 911 912On the T43/p, a typical output may be: 913 914temperatures: 915 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128 916 917The mapping of thermal sensors to physical locations varies depending on 918system-board model (and thus, on ThinkPad model). 919 920https://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that 921tries to track down these locations for various models. 922 923Most (newer?) models seem to follow this pattern: 924 925- 1: CPU 926- 2: (depends on model) 927- 3: (depends on model) 928- 4: GPU 929- 5: Main battery: main sensor 930- 6: Bay battery: main sensor 931- 7: Main battery: secondary sensor 932- 8: Bay battery: secondary sensor 933- 9-15: (depends on model) 934 935For the R51 (source: Thomas Gruber): 936 937- 2: Mini-PCI 938- 3: Internal HDD 939 940For the T43, T43/p (source: Shmidoax/Thinkwiki.org) 941https://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p 942 943- 2: System board, left side (near PCMCIA slot), reported as HDAPS temp 944- 3: PCMCIA slot 945- 9: MCH (northbridge) to DRAM Bus 946- 10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI 947 card, under touchpad 948- 11: Power regulator, underside of system board, below F2 key 949 950The A31 has a very atypical layout for the thermal sensors 951(source: Milos Popovic, https://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31) 952 953- 1: CPU 954- 2: Main Battery: main sensor 955- 3: Power Converter 956- 4: Bay Battery: main sensor 957- 5: MCH (northbridge) 958- 6: PCMCIA/ambient 959- 7: Main Battery: secondary sensor 960- 8: Bay Battery: secondary sensor 961 962 963Procfs notes 964^^^^^^^^^^^^ 965 966 Readings from sensors that are not available return -128. 967 No commands can be written to this file. 968 969Sysfs notes 970^^^^^^^^^^^ 971 972 Sensors that are not available return the ENXIO error. This 973 status may change at runtime, as there are hotplug thermal 974 sensors, like those inside the batteries and docks. 975 976 thinkpad-acpi thermal sensors are reported through the hwmon 977 subsystem, and follow all of the hwmon guidelines at 978 Documentation/hwmon. 979 980EXPERIMENTAL: Embedded controller register dump 981----------------------------------------------- 982 983This feature is not included in the thinkpad driver anymore. 984Instead the EC can be accessed through /sys/kernel/debug/ec with 985a userspace tool which can be found here: 986ftp://ftp.suse.com/pub/people/trenn/sources/ec 987 988Use it to determine the register holding the fan 989speed on some models. To do that, do the following: 990 991 - make sure the battery is fully charged 992 - make sure the fan is running 993 - use above mentioned tool to read out the EC 994 995Often fan and temperature values vary between 996readings. Since temperatures don't change vary fast, you can take 997several quick dumps to eliminate them. 998 999You can use a similar method to figure out the meaning of other 1000embedded controller registers - e.g. make sure nothing else changes 1001except the charging or discharging battery to determine which 1002registers contain the current battery capacity, etc. If you experiment 1003with this, do send me your results (including some complete dumps with 1004a description of the conditions when they were taken.) 1005 1006 1007LCD brightness control 1008---------------------- 1009 1010procfs: /proc/acpi/ibm/brightness 1011 1012sysfs backlight device "thinkpad_screen" 1013 1014This feature allows software control of the LCD brightness on ThinkPad 1015models which don't have a hardware brightness slider. 1016 1017It has some limitations: the LCD backlight cannot be actually turned 1018on or off by this interface, it just controls the backlight brightness 1019level. 1020 1021On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control 1022has eight brightness levels, ranging from 0 to 7. Some of the levels 1023may not be distinct. Later Lenovo models that implement the ACPI 1024display backlight brightness control methods have 16 levels, ranging 1025from 0 to 15. 1026 1027For IBM ThinkPads, there are two interfaces to the firmware for direct 1028brightness control, EC and UCMS (or CMOS). To select which one should be 1029used, use the brightness_mode module parameter: brightness_mode=1 selects 1030EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC 1031mode with NVRAM backing (so that brightness changes are remembered across 1032shutdown/reboot). 1033 1034The driver tries to select which interface to use from a table of 1035defaults for each ThinkPad model. If it makes a wrong choice, please 1036report this as a bug, so that we can fix it. 1037 1038Lenovo ThinkPads only support brightness_mode=2 (UCMS). 1039 1040When display backlight brightness controls are available through the 1041standard ACPI interface, it is best to use it instead of this direct 1042ThinkPad-specific interface. The driver will disable its native 1043backlight brightness control interface if it detects that the standard 1044ACPI interface is available in the ThinkPad. 1045 1046If you want to use the thinkpad-acpi backlight brightness control 1047instead of the generic ACPI video backlight brightness control for some 1048reason, you should use the acpi_backlight=vendor kernel parameter. 1049 1050The brightness_enable module parameter can be used to control whether 1051the LCD brightness control feature will be enabled when available. 1052brightness_enable=0 forces it to be disabled. brightness_enable=1 1053forces it to be enabled when available, even if the standard ACPI 1054interface is also available. 1055 1056Procfs notes 1057^^^^^^^^^^^^ 1058 1059The available commands are:: 1060 1061 echo up >/proc/acpi/ibm/brightness 1062 echo down >/proc/acpi/ibm/brightness 1063 echo 'level <level>' >/proc/acpi/ibm/brightness 1064 1065Sysfs notes 1066^^^^^^^^^^^ 1067 1068The interface is implemented through the backlight sysfs class, which is 1069poorly documented at this time. 1070 1071Locate the thinkpad_screen device under /sys/class/backlight, and inside 1072it there will be the following attributes: 1073 1074 max_brightness: 1075 Reads the maximum brightness the hardware can be set to. 1076 The minimum is always zero. 1077 1078 actual_brightness: 1079 Reads what brightness the screen is set to at this instant. 1080 1081 brightness: 1082 Writes request the driver to change brightness to the 1083 given value. Reads will tell you what brightness the 1084 driver is trying to set the display to when "power" is set 1085 to zero and the display has not been dimmed by a kernel 1086 power management event. 1087 1088 power: 1089 power management mode, where 0 is "display on", and 1 to 3 1090 will dim the display backlight to brightness level 0 1091 because thinkpad-acpi cannot really turn the backlight 1092 off. Kernel power management events can temporarily 1093 increase the current power management level, i.e. they can 1094 dim the display. 1095 1096 1097WARNING: 1098 1099 Whatever you do, do NOT ever call thinkpad-acpi backlight-level change 1100 interface and the ACPI-based backlight level change interface 1101 (available on newer BIOSes, and driven by the Linux ACPI video driver) 1102 at the same time. The two will interact in bad ways, do funny things, 1103 and maybe reduce the life of the backlight lamps by needlessly kicking 1104 its level up and down at every change. 1105 1106 1107Volume control (Console Audio control) 1108-------------------------------------- 1109 1110procfs: /proc/acpi/ibm/volume 1111 1112ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC" 1113 1114NOTE: by default, the volume control interface operates in read-only 1115mode, as it is supposed to be used for on-screen-display purposes. 1116The read/write mode can be enabled through the use of the 1117"volume_control=1" module parameter. 1118 1119NOTE: distros are urged to not enable volume_control by default, this 1120should be done by the local admin only. The ThinkPad UI is for the 1121console audio control to be done through the volume keys only, and for 1122the desktop environment to just provide on-screen-display feedback. 1123Software volume control should be done only in the main AC97/HDA 1124mixer. 1125 1126 1127About the ThinkPad Console Audio control 1128^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1129 1130ThinkPads have a built-in amplifier and muting circuit that drives the 1131console headphone and speakers. This circuit is after the main AC97 1132or HDA mixer in the audio path, and under exclusive control of the 1133firmware. 1134 1135ThinkPads have three special hotkeys to interact with the console 1136audio control: volume up, volume down and mute. 1137 1138It is worth noting that the normal way the mute function works (on 1139ThinkPads that do not have a "mute LED") is: 1140 11411. Press mute to mute. It will *always* mute, you can press it as 1142 many times as you want, and the sound will remain mute. 1143 11442. Press either volume key to unmute the ThinkPad (it will _not_ 1145 change the volume, it will just unmute). 1146 1147This is a very superior design when compared to the cheap software-only 1148mute-toggle solution found on normal consumer laptops: you can be 1149absolutely sure the ThinkPad will not make noise if you press the mute 1150button, no matter the previous state. 1151 1152The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain 1153amplifiers driving the speakers and headphone output, and the firmware 1154also handles volume control for the headphone and speakers on these 1155ThinkPads without any help from the operating system (this volume 1156control stage exists after the main AC97 or HDA mixer in the audio 1157path). 1158 1159The newer Lenovo models only have firmware mute control, and depend on 1160the main HDA mixer to do volume control (which is done by the operating 1161system). In this case, the volume keys are filtered out for unmute 1162key press (there are some firmware bugs in this area) and delivered as 1163normal key presses to the operating system (thinkpad-acpi is not 1164involved). 1165 1166 1167The ThinkPad-ACPI volume control 1168^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1169 1170The preferred way to interact with the Console Audio control is the 1171ALSA interface. 1172 1173The legacy procfs interface allows one to read the current state, 1174and if volume control is enabled, accepts the following commands:: 1175 1176 echo up >/proc/acpi/ibm/volume 1177 echo down >/proc/acpi/ibm/volume 1178 echo mute >/proc/acpi/ibm/volume 1179 echo unmute >/proc/acpi/ibm/volume 1180 echo 'level <level>' >/proc/acpi/ibm/volume 1181 1182The <level> number range is 0 to 14 although not all of them may be 1183distinct. To unmute the volume after the mute command, use either the 1184up or down command (the level command will not unmute the volume), or 1185the unmute command. 1186 1187You can use the volume_capabilities parameter to tell the driver 1188whether your thinkpad has volume control or mute-only control: 1189volume_capabilities=1 for mixers with mute and volume control, 1190volume_capabilities=2 for mixers with only mute control. 1191 1192If the driver misdetects the capabilities for your ThinkPad model, 1193please report this to ibm-acpi-devel@lists.sourceforge.net, so that we 1194can update the driver. 1195 1196There are two strategies for volume control. To select which one 1197should be used, use the volume_mode module parameter: volume_mode=1 1198selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing 1199(so that volume/mute changes are remembered across shutdown/reboot). 1200 1201The driver will operate in volume_mode=3 by default. If that does not 1202work well on your ThinkPad model, please report this to 1203ibm-acpi-devel@lists.sourceforge.net. 1204 1205The driver supports the standard ALSA module parameters. If the ALSA 1206mixer is disabled, the driver will disable all volume functionality. 1207 1208 1209Fan control and monitoring: fan speed, fan enable/disable 1210--------------------------------------------------------- 1211 1212procfs: /proc/acpi/ibm/fan 1213 1214sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1, pwm1_enable, fan2_input 1215 1216sysfs hwmon driver attributes: fan_watchdog 1217 1218NOTE NOTE NOTE: 1219 fan control operations are disabled by default for 1220 safety reasons. To enable them, the module parameter "fan_control=1" 1221 must be given to thinkpad-acpi. 1222 1223This feature attempts to show the current fan speed, control mode and 1224other fan data that might be available. The speed is read directly 1225from the hardware registers of the embedded controller. This is known 1226to work on later R, T, X and Z series ThinkPads but may show a bogus 1227value on other models. 1228 1229Some Lenovo ThinkPads support a secondary fan. This fan cannot be 1230controlled separately, it shares the main fan control. 1231 1232Fan levels 1233^^^^^^^^^^ 1234 1235Most ThinkPad fans work in "levels" at the firmware interface. Level 0 1236stops the fan. The higher the level, the higher the fan speed, although 1237adjacent levels often map to the same fan speed. 7 is the highest 1238level, where the fan reaches the maximum recommended speed. 1239 1240Level "auto" means the EC changes the fan level according to some 1241internal algorithm, usually based on readings from the thermal sensors. 1242 1243There is also a "full-speed" level, also known as "disengaged" level. 1244In this level, the EC disables the speed-locked closed-loop fan control, 1245and drives the fan as fast as it can go, which might exceed hardware 1246limits, so use this level with caution. 1247 1248The fan usually ramps up or down slowly from one speed to another, and 1249it is normal for the EC to take several seconds to react to fan 1250commands. The full-speed level may take up to two minutes to ramp up to 1251maximum speed, and in some ThinkPads, the tachometer readings go stale 1252while the EC is transitioning to the full-speed level. 1253 1254WARNING WARNING WARNING: do not leave the fan disabled unless you are 1255monitoring all of the temperature sensor readings and you are ready to 1256enable it if necessary to avoid overheating. 1257 1258An enabled fan in level "auto" may stop spinning if the EC decides the 1259ThinkPad is cool enough and doesn't need the extra airflow. This is 1260normal, and the EC will spin the fan up if the various thermal readings 1261rise too much. 1262 1263On the X40, this seems to depend on the CPU and HDD temperatures. 1264Specifically, the fan is turned on when either the CPU temperature 1265climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The 1266fan is turned off when the CPU temperature drops to 49 degrees and the 1267HDD temperature drops to 41 degrees. These thresholds cannot 1268currently be controlled. 1269 1270The ThinkPad's ACPI DSDT code will reprogram the fan on its own when 1271certain conditions are met. It will override any fan programming done 1272through thinkpad-acpi. 1273 1274The thinkpad-acpi kernel driver can be programmed to revert the fan 1275level to a safe setting if userspace does not issue one of the procfs 1276fan commands: "enable", "disable", "level" or "watchdog", or if there 1277are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is 1278set to 1, manual mode) within a configurable amount of time of up to 1279120 seconds. This functionality is called fan safety watchdog. 1280 1281Note that the watchdog timer stops after it enables the fan. It will be 1282rearmed again automatically (using the same interval) when one of the 1283above mentioned fan commands is received. The fan watchdog is, 1284therefore, not suitable to protect against fan mode changes made through 1285means other than the "enable", "disable", and "level" procfs fan 1286commands, or the hwmon fan control sysfs interface. 1287 1288Procfs notes 1289^^^^^^^^^^^^ 1290 1291The fan may be enabled or disabled with the following commands:: 1292 1293 echo enable >/proc/acpi/ibm/fan 1294 echo disable >/proc/acpi/ibm/fan 1295 1296Placing a fan on level 0 is the same as disabling it. Enabling a fan 1297will try to place it in a safe level if it is too slow or disabled. 1298 1299The fan level can be controlled with the command:: 1300 1301 echo 'level <level>' > /proc/acpi/ibm/fan 1302 1303Where <level> is an integer from 0 to 7, or one of the words "auto" or 1304"full-speed" (without the quotes). Not all ThinkPads support the "auto" 1305and "full-speed" levels. The driver accepts "disengaged" as an alias for 1306"full-speed", and reports it as "disengaged" for backwards 1307compatibility. 1308 1309On the X31 and X40 (and ONLY on those models), the fan speed can be 1310controlled to a certain degree. Once the fan is running, it can be 1311forced to run faster or slower with the following command:: 1312 1313 echo 'speed <speed>' > /proc/acpi/ibm/fan 1314 1315The sustainable range of fan speeds on the X40 appears to be from about 13163700 to about 7350. Values outside this range either do not have any 1317effect or the fan speed eventually settles somewhere in that range. The 1318fan cannot be stopped or started with this command. This functionality 1319is incomplete, and not available through the sysfs interface. 1320 1321To program the safety watchdog, use the "watchdog" command:: 1322 1323 echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan 1324 1325If you want to disable the watchdog, use 0 as the interval. 1326 1327Sysfs notes 1328^^^^^^^^^^^ 1329 1330The sysfs interface follows the hwmon subsystem guidelines for the most 1331part, and the exception is the fan safety watchdog. 1332 1333Writes to any of the sysfs attributes may return the EINVAL error if 1334that operation is not supported in a given ThinkPad or if the parameter 1335is out-of-bounds, and EPERM if it is forbidden. They may also return 1336EINTR (interrupted system call), and EIO (I/O error while trying to talk 1337to the firmware). 1338 1339Features not yet implemented by the driver return ENOSYS. 1340 1341hwmon device attribute pwm1_enable: 1342 - 0: PWM offline (fan is set to full-speed mode) 1343 - 1: Manual PWM control (use pwm1 to set fan level) 1344 - 2: Hardware PWM control (EC "auto" mode) 1345 - 3: reserved (Software PWM control, not implemented yet) 1346 1347 Modes 0 and 2 are not supported by all ThinkPads, and the 1348 driver is not always able to detect this. If it does know a 1349 mode is unsupported, it will return -EINVAL. 1350 1351hwmon device attribute pwm1: 1352 Fan level, scaled from the firmware values of 0-7 to the hwmon 1353 scale of 0-255. 0 means fan stopped, 255 means highest normal 1354 speed (level 7). 1355 1356 This attribute only commands the fan if pmw1_enable is set to 1 1357 (manual PWM control). 1358 1359hwmon device attribute fan1_input: 1360 Fan tachometer reading, in RPM. May go stale on certain 1361 ThinkPads while the EC transitions the PWM to offline mode, 1362 which can take up to two minutes. May return rubbish on older 1363 ThinkPads. 1364 1365hwmon device attribute fan2_input: 1366 Fan tachometer reading, in RPM, for the secondary fan. 1367 Available only on some ThinkPads. If the secondary fan is 1368 not installed, will always read 0. 1369 1370hwmon driver attribute fan_watchdog: 1371 Fan safety watchdog timer interval, in seconds. Minimum is 1372 1 second, maximum is 120 seconds. 0 disables the watchdog. 1373 1374To stop the fan: set pwm1 to zero, and pwm1_enable to 1. 1375 1376To start the fan in a safe mode: set pwm1_enable to 2. If that fails 1377with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255 1378would be the safest choice, though). 1379 1380 1381WAN 1382--- 1383 1384procfs: /proc/acpi/ibm/wan 1385 1386sysfs device attribute: wwan_enable (deprecated) 1387 1388sysfs rfkill class: switch "tpacpi_wwan_sw" 1389 1390This feature shows the presence and current state of the built-in 1391Wireless WAN device. 1392 1393If the ThinkPad supports it, the WWAN state is stored in NVRAM, 1394so it is kept across reboots and power-off. 1395 1396It was tested on a Lenovo ThinkPad X60. It should probably work on other 1397ThinkPad models which come with this module installed. 1398 1399Procfs notes 1400^^^^^^^^^^^^ 1401 1402If the W-WAN card is installed, the following commands can be used:: 1403 1404 echo enable > /proc/acpi/ibm/wan 1405 echo disable > /proc/acpi/ibm/wan 1406 1407Sysfs notes 1408^^^^^^^^^^^ 1409 1410 If the W-WAN card is installed, it can be enabled / 1411 disabled through the "wwan_enable" thinkpad-acpi device 1412 attribute, and its current status can also be queried. 1413 1414 enable: 1415 - 0: disables WWAN card / WWAN card is disabled 1416 - 1: enables WWAN card / WWAN card is enabled. 1417 1418 Note: this interface has been superseded by the generic rfkill 1419 class. It has been deprecated, and it will be removed in year 1420 2010. 1421 1422 rfkill controller switch "tpacpi_wwan_sw": refer to 1423 Documentation/driver-api/rfkill.rst for details. 1424 1425 1426LCD Shadow control 1427------------------ 1428 1429procfs: /proc/acpi/ibm/lcdshadow 1430 1431Some newer T480s and T490s ThinkPads provide a feature called 1432PrivacyGuard. By turning this feature on, the usable vertical and 1433horizontal viewing angles of the LCD can be limited (as if some privacy 1434screen was applied manually in front of the display). 1435 1436procfs notes 1437^^^^^^^^^^^^ 1438 1439The available commands are:: 1440 1441 echo '0' >/proc/acpi/ibm/lcdshadow 1442 echo '1' >/proc/acpi/ibm/lcdshadow 1443 1444The first command ensures the best viewing angle and the latter one turns 1445on the feature, restricting the viewing angles. 1446 1447 1448DYTC Lapmode sensor 1449------------------- 1450 1451sysfs: dytc_lapmode 1452 1453Newer thinkpads and mobile workstations have the ability to determine if 1454the device is in deskmode or lapmode. This feature is used by user space 1455to decide if WWAN transmission can be increased to maximum power and is 1456also useful for understanding the different thermal modes available as 1457they differ between desk and lap mode. 1458 1459The property is read-only. If the platform doesn't have support the sysfs 1460class is not created. 1461 1462EXPERIMENTAL: UWB 1463----------------- 1464 1465This feature is considered EXPERIMENTAL because it has not been extensively 1466tested and validated in various ThinkPad models yet. The feature may not 1467work as expected. USE WITH CAUTION! To use this feature, you need to supply 1468the experimental=1 parameter when loading the module. 1469 1470sysfs rfkill class: switch "tpacpi_uwb_sw" 1471 1472This feature exports an rfkill controller for the UWB device, if one is 1473present and enabled in the BIOS. 1474 1475Sysfs notes 1476^^^^^^^^^^^ 1477 1478 rfkill controller switch "tpacpi_uwb_sw": refer to 1479 Documentation/driver-api/rfkill.rst for details. 1480 1481 1482Setting keyboard language 1483------------------------- 1484 1485sysfs: keyboard_lang 1486 1487This feature is used to set keyboard language to ECFW using ASL interface. 1488Fewer thinkpads models like T580 , T590 , T15 Gen 1 etc.. has "=", "(', 1489")" numeric keys, which are not displaying correctly, when keyboard language 1490is other than "english". This is because the default keyboard language in ECFW 1491is set as "english". Hence using this sysfs, user can set the correct keyboard 1492language to ECFW and then these key's will work correctly. 1493 1494Example of command to set keyboard language is mentioned below:: 1495 1496 echo jp > /sys/devices/platform/thinkpad_acpi/keyboard_lang 1497 1498Text corresponding to keyboard layout to be set in sysfs are: be(Belgian), 1499cz(Czech), da(Danish), de(German), en(English), es(Spain), et(Estonian), 1500fr(French), fr-ch(French(Switzerland)), hu(Hungarian), it(Italy), jp (Japan), 1501nl(Dutch), nn(Norway), pl(Polish), pt(portuguese), sl(Slovenian), sv(Sweden), 1502tr(Turkey) 1503 1504WWAN Antenna type 1505----------------- 1506 1507sysfs: wwan_antenna_type 1508 1509On some newer Thinkpads we need to set SAR value based on the antenna 1510type. This interface will be used by userspace to get the antenna type 1511and set the corresponding SAR value, as is required for FCC certification. 1512 1513The available commands are:: 1514 1515 cat /sys/devices/platform/thinkpad_acpi/wwan_antenna_type 1516 1517Currently 2 antenna types are supported as mentioned below: 1518- type a 1519- type b 1520 1521The property is read-only. If the platform doesn't have support the sysfs 1522class is not created. 1523 1524Auxmac 1525------ 1526 1527sysfs: auxmac 1528 1529Some newer Thinkpads have a feature called MAC Address Pass-through. This 1530feature is implemented by the system firmware to provide a system unique MAC, 1531that can override a dock or USB ethernet dongle MAC, when connected to a 1532network. This property enables user-space to easily determine the MAC address 1533if the feature is enabled. 1534 1535The values of this auxiliary MAC are: 1536 1537 cat /sys/devices/platform/thinkpad_acpi/auxmac 1538 1539If the feature is disabled, the value will be 'disabled'. 1540 1541This property is read-only. 1542 1543Adaptive keyboard 1544----------------- 1545 1546sysfs device attribute: adaptive_kbd_mode 1547 1548This sysfs attribute controls the keyboard "face" that will be shown on the 1549Lenovo X1 Carbon 2nd gen (2014)'s adaptive keyboard. The value can be read 1550and set. 1551 1552- 0 = Home mode 1553- 1 = Web-browser mode 1554- 2 = Web-conference mode 1555- 3 = Function mode 1556- 4 = Layflat mode 1557 1558For more details about which buttons will appear depending on the mode, please 1559review the laptop's user guide: 1560https://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles_pdf/x1carbon_2_ug_en.pdf 1561 1562Battery charge control 1563---------------------- 1564 1565sysfs attributes: 1566/sys/class/power_supply/BAT*/charge_control_{start,end}_threshold 1567 1568These two attributes are created for those batteries that are supported by the 1569driver. They enable the user to control the battery charge thresholds of the 1570given battery. Both values may be read and set. `charge_control_start_threshold` 1571accepts an integer between 0 and 99 (inclusive); this value represents a battery 1572percentage level, below which charging will begin. `charge_control_end_threshold` 1573accepts an integer between 1 and 100 (inclusive); this value represents a battery 1574percentage level, above which charging will stop. 1575 1576The exact semantics of the attributes may be found in 1577Documentation/ABI/testing/sysfs-class-power. 1578 1579Multiple Commands, Module Parameters 1580------------------------------------ 1581 1582Multiple commands can be written to the proc files in one shot by 1583separating them with commas, for example:: 1584 1585 echo enable,0xffff > /proc/acpi/ibm/hotkey 1586 echo lcd_disable,crt_enable > /proc/acpi/ibm/video 1587 1588Commands can also be specified when loading the thinkpad-acpi module, 1589for example:: 1590 1591 modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable 1592 1593 1594Enabling debugging output 1595------------------------- 1596 1597The module takes a debug parameter which can be used to selectively 1598enable various classes of debugging output, for example:: 1599 1600 modprobe thinkpad_acpi debug=0xffff 1601 1602will enable all debugging output classes. It takes a bitmask, so 1603to enable more than one output class, just add their values. 1604 1605 ============= ====================================== 1606 Debug bitmask Description 1607 ============= ====================================== 1608 0x8000 Disclose PID of userspace programs 1609 accessing some functions of the driver 1610 0x0001 Initialization and probing 1611 0x0002 Removal 1612 0x0004 RF Transmitter control (RFKILL) 1613 (bluetooth, WWAN, UWB...) 1614 0x0008 HKEY event interface, hotkeys 1615 0x0010 Fan control 1616 0x0020 Backlight brightness 1617 0x0040 Audio mixer/volume control 1618 ============= ====================================== 1619 1620There is also a kernel build option to enable more debugging 1621information, which may be necessary to debug driver problems. 1622 1623The level of debugging information output by the driver can be changed 1624at runtime through sysfs, using the driver attribute debug_level. The 1625attribute takes the same bitmask as the debug module parameter above. 1626 1627 1628Force loading of module 1629----------------------- 1630 1631If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify 1632the module parameter force_load=1. Regardless of whether this works or 1633not, please contact ibm-acpi-devel@lists.sourceforge.net with a report. 1634 1635 1636Sysfs interface changelog 1637^^^^^^^^^^^^^^^^^^^^^^^^^ 1638 1639========= =============================================================== 16400x000100: Initial sysfs support, as a single platform driver and 1641 device. 16420x000200: Hot key support for 32 hot keys, and radio slider switch 1643 support. 16440x010000: Hot keys are now handled by default over the input 1645 layer, the radio switch generates input event EV_RADIO, 1646 and the driver enables hot key handling by default in 1647 the firmware. 1648 16490x020000: ABI fix: added a separate hwmon platform device and 1650 driver, which must be located by name (thinkpad) 1651 and the hwmon class for libsensors4 (lm-sensors 3) 1652 compatibility. Moved all hwmon attributes to this 1653 new platform device. 1654 16550x020100: Marker for thinkpad-acpi with hot key NVRAM polling 1656 support. If you must, use it to know you should not 1657 start a userspace NVRAM poller (allows to detect when 1658 NVRAM is compiled out by the user because it is 1659 unneeded/undesired in the first place). 16600x020101: Marker for thinkpad-acpi with hot key NVRAM polling 1661 and proper hotkey_mask semantics (version 8 of the 1662 NVRAM polling patch). Some development snapshots of 1663 0.18 had an earlier version that did strange things 1664 to hotkey_mask. 1665 16660x020200: Add poll()/select() support to the following attributes: 1667 hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason 1668 16690x020300: hotkey enable/disable support removed, attributes 1670 hotkey_bios_enabled and hotkey_enable deprecated and 1671 marked for removal. 1672 16730x020400: Marker for 16 LEDs support. Also, LEDs that are known 1674 to not exist in a given model are not registered with 1675 the LED sysfs class anymore. 1676 16770x020500: Updated hotkey driver, hotkey_mask is always available 1678 and it is always able to disable hot keys. Very old 1679 thinkpads are properly supported. hotkey_bios_mask 1680 is deprecated and marked for removal. 1681 16820x020600: Marker for backlight change event support. 1683 16840x020700: Support for mute-only mixers. 1685 Volume control in read-only mode by default. 1686 Marker for ALSA mixer support. 1687 16880x030000: Thermal and fan sysfs attributes were moved to the hwmon 1689 device instead of being attached to the backing platform 1690 device. 1691========= =============================================================== 1692