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- ThinkPad ACPI Extras Driver
-
- Version 0.24
- December 11th, 2009
-
- Borislav Deianov <borislav@users.sf.net>
- Henrique de Moraes Holschuh <hmh@hmh.eng.br>
- http://ibm-acpi.sf.net/
-
-
-This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It
-supports various features of these laptops which are accessible
-through the ACPI and ACPI EC framework, but not otherwise fully
-supported by the generic Linux ACPI drivers.
-
-This driver used to be named ibm-acpi until kernel 2.6.21 and release
-0.13-20070314. It used to be in the drivers/acpi tree, but it was
-moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel
-2.6.22, and release 0.14. It was moved to drivers/platform/x86 for
-kernel 2.6.29 and release 0.22.
-
-The driver is named "thinkpad-acpi". In some places, like module
-names and log messages, "thinkpad_acpi" is used because of userspace
-issues.
-
-"tpacpi" is used as a shorthand where "thinkpad-acpi" would be too
-long due to length limitations on some Linux kernel versions.
-
-Status
-------
-
-The features currently supported are the following (see below for
-detailed description):
-
- - Fn key combinations
- - Bluetooth enable and disable
- - video output switching, expansion control
- - ThinkLight on and off
- - CMOS/UCMS control
- - LED control
- - ACPI sounds
- - temperature sensors
- - Experimental: embedded controller register dump
- - LCD brightness control
- - Volume control
- - Fan control and monitoring: fan speed, fan enable/disable
- - WAN enable and disable
- - UWB enable and disable
-
-A compatibility table by model and feature is maintained on the web
-site, http://ibm-acpi.sf.net/. I appreciate any success or failure
-reports, especially if they add to or correct the compatibility table.
-Please include the following information in your report:
-
- - ThinkPad model name
- - a copy of your ACPI tables, using the "acpidump" utility
- - a copy of the output of dmidecode, with serial numbers
- and UUIDs masked off
- - which driver features work and which don't
- - the observed behavior of non-working features
-
-Any other comments or patches are also more than welcome.
-
-
-Installation
-------------
-
-If you are compiling this driver as included in the Linux kernel
-sources, look for the CONFIG_THINKPAD_ACPI Kconfig option.
-It is located on the menu path: "Device Drivers" -> "X86 Platform
-Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras".
-
-
-Features
---------
-
-The driver exports two different interfaces to userspace, which can be
-used to access the features it provides. One is a legacy procfs-based
-interface, which will be removed at some time in the future. The other
-is a new sysfs-based interface which is not complete yet.
-
-The procfs interface creates the /proc/acpi/ibm directory. There is a
-file under that directory for each feature it supports. The procfs
-interface is mostly frozen, and will change very little if at all: it
-will not be extended to add any new functionality in the driver, instead
-all new functionality will be implemented on the sysfs interface.
-
-The sysfs interface tries to blend in the generic Linux sysfs subsystems
-and classes as much as possible. Since some of these subsystems are not
-yet ready or stabilized, it is expected that this interface will change,
-and any and all userspace programs must deal with it.
-
-
-Notes about the sysfs interface:
-
-Unlike what was done with the procfs interface, correctness when talking
-to the sysfs interfaces will be enforced, as will correctness in the
-thinkpad-acpi's implementation of sysfs interfaces.
-
-Also, any bugs in the thinkpad-acpi sysfs driver code or in the
-thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
-maximum correctness, even if that means changing an interface in
-non-compatible ways. As these interfaces mature both in the kernel and
-in thinkpad-acpi, such changes should become quite rare.
-
-Applications interfacing to the thinkpad-acpi sysfs interfaces must
-follow all sysfs guidelines and correctly process all errors (the sysfs
-interface makes extensive use of errors). File descriptors and open /
-close operations to the sysfs inodes must also be properly implemented.
-
-The version of thinkpad-acpi's sysfs interface is exported by the driver
-as a driver attribute (see below).
-
-Sysfs driver attributes are on the driver's sysfs attribute space,
-for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and
-/sys/bus/platform/drivers/thinkpad_hwmon/
-
-Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
-space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/.
-
-Sysfs device attributes for the sensors and fan are on the
-thinkpad_hwmon device's sysfs attribute space, but you should locate it
-looking for a hwmon device with the name attribute of "thinkpad", or
-better yet, through libsensors.
-
-
-Driver version
---------------
-
-procfs: /proc/acpi/ibm/driver
-sysfs driver attribute: version
-
-The driver name and version. No commands can be written to this file.
-
-
-Sysfs interface version
------------------------
-
-sysfs driver attribute: interface_version
-
-Version of the thinkpad-acpi sysfs interface, as an unsigned long
-(output in hex format: 0xAAAABBCC), where:
- AAAA - major revision
- BB - minor revision
- CC - bugfix revision
-
-The sysfs interface version changelog for the driver can be found at the
-end of this document. Changes to the sysfs interface done by the kernel
-subsystems are not documented here, nor are they tracked by this
-attribute.
-
-Changes to the thinkpad-acpi sysfs interface are only considered
-non-experimental when they are submitted to Linux mainline, at which
-point the changes in this interface are documented and interface_version
-may be updated. If you are using any thinkpad-acpi features not yet
-sent to mainline for merging, you do so on your own risk: these features
-may disappear, or be implemented in a different and incompatible way by
-the time they are merged in Linux mainline.
-
-Changes that are backwards-compatible by nature (e.g. the addition of
-attributes that do not change the way the other attributes work) do not
-always warrant an update of interface_version. Therefore, one must
-expect that an attribute might not be there, and deal with it properly
-(an attribute not being there *is* a valid way to make it clear that a
-feature is not available in sysfs).
-
-
-Hot keys
---------
-
-procfs: /proc/acpi/ibm/hotkey
-sysfs device attribute: hotkey_*
-
-In a ThinkPad, the ACPI HKEY handler is responsible for communicating
-some important events and also keyboard hot key presses to the operating
-system. Enabling the hotkey functionality of thinkpad-acpi signals the
-firmware that such a driver is present, and modifies how the ThinkPad
-firmware will behave in many situations.
-
-The driver enables the HKEY ("hot key") event reporting automatically
-when loaded, and disables it when it is removed.
-
-The driver will report HKEY events in the following format:
-
- ibm/hotkey HKEY 00000080 0000xxxx
-
-Some of these events refer to hot key presses, but not all of them.
-
-The driver will generate events over the input layer for hot keys and
-radio switches, and over the ACPI netlink layer for other events. The
-input layer support accepts the standard IOCTLs to remap the keycodes
-assigned to each hot key.
-
-The hot key bit mask allows some control over which hot keys generate
-events. If a key is "masked" (bit set to 0 in the mask), the firmware
-will handle it. If it is "unmasked", it signals the firmware that
-thinkpad-acpi would prefer to handle it, if the firmware would be so
-kind to allow it (and it often doesn't!).
-
-Not all bits in the mask can be modified. Not all bits that can be
-modified do anything. Not all hot keys can be individually controlled
-by the mask. Some models do not support the mask at all. The behaviour
-of the mask is, therefore, highly dependent on the ThinkPad model.
-
-The driver will filter out any unmasked hotkeys, so even if the firmware
-doesn't allow disabling an specific hotkey, the driver will not report
-events for unmasked hotkeys.
-
-Note that unmasking some keys prevents their default behavior. For
-example, if Fn+F5 is unmasked, that key will no longer enable/disable
-Bluetooth by itself in firmware.
-
-Note also that not all Fn key combinations are supported through ACPI
-depending on the ThinkPad model and firmware version. On those
-ThinkPads, it is still possible to support some extra hotkeys by
-polling the "CMOS NVRAM" at least 10 times per second. The driver
-attempts to enables this functionality automatically when required.
-
-procfs notes:
-
-The following commands can be written to the /proc/acpi/ibm/hotkey file:
-
- echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
- echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
- ... any other 8-hex-digit mask ...
- echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask
-
-The following commands have been deprecated and will cause the kernel
-to log a warning:
-
- echo enable > /proc/acpi/ibm/hotkey -- does nothing
- echo disable > /proc/acpi/ibm/hotkey -- returns an error
-
-The procfs interface does not support NVRAM polling control. So as to
-maintain maximum bug-to-bug compatibility, it does not report any masks,
-nor does it allow one to manipulate the hot key mask when the firmware
-does not support masks at all, even if NVRAM polling is in use.
-
-sysfs notes:
-
- hotkey_bios_enabled:
- DEPRECATED, WILL BE REMOVED SOON.
-
- Returns 0.
-
- hotkey_bios_mask:
- DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE.
-
- Returns the hot keys mask when thinkpad-acpi was loaded.
- Upon module unload, the hot keys mask will be restored
- to this value. This is always 0x80c, because those are
- the hotkeys that were supported by ancient firmware
- without mask support.
-
- hotkey_enable:
- DEPRECATED, WILL BE REMOVED SOON.
-
- 0: returns -EPERM
- 1: does nothing
-
- hotkey_mask:
- bit mask to enable reporting (and depending on
- the firmware, ACPI event generation) for each hot key
- (see above). Returns the current status of the hot keys
- mask, and allows one to modify it.
-
- hotkey_all_mask:
- bit mask that should enable event reporting for all
- supported hot keys, when echoed to hotkey_mask above.
- Unless you know which events need to be handled
- passively (because the firmware *will* handle them
- anyway), do *not* use hotkey_all_mask. Use
- hotkey_recommended_mask, instead. You have been warned.
-
- hotkey_recommended_mask:
- bit mask that should enable event reporting for all
- supported hot keys, except those which are always
- handled by the firmware anyway. Echo it to
- hotkey_mask above, to use. This is the default mask
- used by the driver.
-
- hotkey_source_mask:
- bit mask that selects which hot keys will the driver
- poll the NVRAM for. This is auto-detected by the driver
- based on the capabilities reported by the ACPI firmware,
- but it can be overridden at runtime.
-
- Hot keys whose bits are set in hotkey_source_mask are
- polled for in NVRAM, and reported as hotkey events if
- enabled in hotkey_mask. Only a few hot keys are
- available through CMOS NVRAM polling.
-
- Warning: when in NVRAM mode, the volume up/down/mute
- keys are synthesized according to changes in the mixer,
- which uses a single volume up or volume down hotkey
- press to unmute, as per the ThinkPad volume mixer user
- interface. When in ACPI event mode, volume up/down/mute
- events are reported by the firmware and can behave
- differently (and that behaviour changes with firmware
- version -- not just with firmware models -- as well as
- OSI(Linux) state).
-
- hotkey_poll_freq:
- frequency in Hz for hot key polling. It must be between
- 0 and 25 Hz. Polling is only carried out when strictly
- needed.
-
- Setting hotkey_poll_freq to zero disables polling, and
- will cause hot key presses that require NVRAM polling
- to never be reported.
-
- Setting hotkey_poll_freq too low may cause repeated
- pressings of the same hot key to be misreported as a
- single key press, or to not even be detected at all.
- The recommended polling frequency is 10Hz.
-
- hotkey_radio_sw:
- If the ThinkPad has a hardware radio switch, this
- attribute will read 0 if the switch is in the "radios
- disabled" position, and 1 if the switch is in the
- "radios enabled" position.
-
- This attribute has poll()/select() support.
-
- hotkey_tablet_mode:
- If the ThinkPad has tablet capabilities, this attribute
- will read 0 if the ThinkPad is in normal mode, and
- 1 if the ThinkPad is in tablet mode.
-
- This attribute has poll()/select() support.
-
- hotkey_report_mode:
- Returns the state of the procfs ACPI event report mode
- filter for hot keys. If it is set to 1 (the default),
- all hot key presses are reported both through the input
- layer and also as ACPI events through procfs (but not
- through netlink). If it is set to 2, hot key presses
- are reported only through the input layer.
-
- This attribute is read-only in kernels 2.6.23 or later,
- and read-write on earlier kernels.
-
- May return -EPERM (write access locked out by module
- parameter) or -EACCES (read-only).
-
- wakeup_reason:
- Set to 1 if the system is waking up because the user
- requested a bay ejection. Set to 2 if the system is
- waking up because the user requested the system to
- undock. Set to zero for normal wake-ups or wake-ups
- due to unknown reasons.
-
- This attribute has poll()/select() support.
-
- wakeup_hotunplug_complete:
- Set to 1 if the system was waken up because of an
- undock or bay ejection request, and that request
- was successfully completed. At this point, it might
- be useful to send the system back to sleep, at the
- user's choice. Refer to HKEY events 0x4003 and
- 0x3003, below.
-
- This attribute has poll()/select() support.
-
-input layer notes:
-
-A Hot key is mapped to a single input layer EV_KEY event, possibly
-followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
-code. An EV_SYN event will always be generated to mark the end of the
-event block.
-
-Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
-used as a helper to remap keys, only. They are particularly useful when
-remapping KEY_UNKNOWN keys.
-
-The events are available in an input device, with the following id:
-
- Bus: BUS_HOST
- vendor: 0x1014 (PCI_VENDOR_ID_IBM) or
- 0x17aa (PCI_VENDOR_ID_LENOVO)
- product: 0x5054 ("TP")
- version: 0x4101
-
-The version will have its LSB incremented if the keymap changes in a
-backwards-compatible way. The MSB shall always be 0x41 for this input
-device. If the MSB is not 0x41, do not use the device as described in
-this section, as it is either something else (e.g. another input device
-exported by a thinkpad driver, such as HDAPS) or its functionality has
-been changed in a non-backwards compatible way.
-
-Adding other event types for other functionalities shall be considered a
-backwards-compatible change for this input device.
-
-Thinkpad-acpi Hot Key event map (version 0x4101):
-
-ACPI Scan
-event code Key Notes
-
-0x1001 0x00 FN+F1 -
-
-0x1002 0x01 FN+F2 IBM: battery (rare)
- Lenovo: Screen lock
-
-0x1003 0x02 FN+F3 Many IBM models always report
- this hot key, even with hot keys
- disabled or with Fn+F3 masked
- off
- IBM: screen lock, often turns
- off the ThinkLight as side-effect
- Lenovo: battery
-
-0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
- semantics, i.e. sleep-to-RAM).
- It always generates some kind
- of event, either the hot key
- event or an ACPI sleep button
- event. The firmware may
- refuse to generate further FN+F4
- key presses until a S3 or S4 ACPI
- sleep cycle is performed or some
- time passes.
-
-0x1005 0x04 FN+F5 Radio. Enables/disables
- the internal Bluetooth hardware
- and W-WAN card if left in control
- of the firmware. Does not affect
- the WLAN card.
- Should be used to turn on/off all
- radios (Bluetooth+W-WAN+WLAN),
- really.
-
-0x1006 0x05 FN+F6 -
-
-0x1007 0x06 FN+F7 Video output cycle.
- Do you feel lucky today?
-
-0x1008 0x07 FN+F8 IBM: toggle screen expand
- Lenovo: configure UltraNav,
- or toggle screen expand
-
-0x1009 0x08 FN+F9 -
- .. .. ..
-0x100B 0x0A FN+F11 -
-
-0x100C 0x0B FN+F12 Sleep to disk. You are always
- supposed to handle it yourself,
- either through the ACPI event,
- or through a hotkey event.
- The firmware may refuse to
- generate further FN+F12 key
- press events until a S3 or S4
- ACPI sleep cycle is performed,
- or some time passes.
-
-0x100D 0x0C FN+BACKSPACE -
-0x100E 0x0D FN+INSERT -
-0x100F 0x0E FN+DELETE -
-
-0x1010 0x0F FN+HOME Brightness up. This key is
- always handled by the firmware
- in IBM ThinkPads, even when
- unmasked. Just leave it alone.
- For Lenovo ThinkPads with a new
- BIOS, it has to be handled either
- by the ACPI OSI, or by userspace.
- The driver does the right thing,
- never mess with this.
-0x1011 0x10 FN+END Brightness down. See brightness
- up for details.
-
-0x1012 0x11 FN+PGUP ThinkLight toggle. This key is
- always handled by the firmware,
- even when unmasked.
-
-0x1013 0x12 FN+PGDOWN -
-
-0x1014 0x13 FN+SPACE Zoom key
-
-0x1015 0x14 VOLUME UP Internal mixer volume up. This
- key is always handled by the
- firmware, even when unmasked.
- NOTE: Lenovo seems to be changing
- this.
-0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
- key is always handled by the
- firmware, even when unmasked.
- NOTE: Lenovo seems to be changing
- this.
-0x1017 0x16 MUTE Mute internal mixer. This
- key is always handled by the
- firmware, even when unmasked.
-
-0x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key
-
-0x1019 0x18 unknown
-.. .. ..
-0x1020 0x1F unknown
-
-The ThinkPad firmware does not allow one to differentiate when most hot
-keys are pressed or released (either that, or we don't know how to, yet).
-For these keys, the driver generates a set of events for a key press and
-immediately issues the same set of events for a key release. It is
-unknown by the driver if the ThinkPad firmware triggered these events on
-hot key press or release, but the firmware will do it for either one, not
-both.
-
-If a key is mapped to KEY_RESERVED, it generates no input events at all.
-If a key is mapped to KEY_UNKNOWN, it generates an input event that
-includes an scan code. If a key is mapped to anything else, it will
-generate input device EV_KEY events.
-
-In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
-events for switches:
-
-SW_RFKILL_ALL T60 and later hardware rfkill rocker switch
-SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
-
-Non hotkey ACPI HKEY event map:
--------------------------------
-
-Events that are not propagated by the driver, except for legacy
-compatibility purposes when hotkey_report_mode is set to 1:
-
-0x5001 Lid closed
-0x5002 Lid opened
-0x5009 Tablet swivel: switched to tablet mode
-0x500A Tablet swivel: switched to normal mode
-0x7000 Radio Switch may have changed state
-
-Events that are never propagated by the driver:
-
-0x2304 System is waking up from suspend to undock
-0x2305 System is waking up from suspend to eject bay
-0x2404 System is waking up from hibernation to undock
-0x2405 System is waking up from hibernation to eject bay
-0x5010 Brightness level changed/control event
-0x6000 KEYBOARD: Numlock key pressed
-0x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED)
-
-Events that are propagated by the driver to userspace:
-
-0x2313 ALARM: System is waking up from suspend because
- the battery is nearly empty
-0x2413 ALARM: System is waking up from hibernation because
- the battery is nearly empty
-0x3003 Bay ejection (see 0x2x05) complete, can sleep again
-0x3006 Bay hotplug request (hint to power up SATA link when
- the optical drive tray is ejected)
-0x4003 Undocked (see 0x2x04), can sleep again
-0x4010 Docked into hotplug port replicator (non-ACPI dock)
-0x4011 Undocked from hotplug port replicator (non-ACPI dock)
-0x500B Tablet pen inserted into its storage bay
-0x500C Tablet pen removed from its storage bay
-0x6011 ALARM: battery is too hot
-0x6012 ALARM: battery is extremely hot
-0x6021 ALARM: a sensor is too hot
-0x6022 ALARM: a sensor is extremely hot
-0x6030 System thermal table changed
-0x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED)
-
-Battery nearly empty alarms are a last resort attempt to get the
-operating system to hibernate or shutdown cleanly (0x2313), or shutdown
-cleanly (0x2413) before power is lost. They must be acted upon, as the
-wake up caused by the firmware will have negated most safety nets...
-
-When any of the "too hot" alarms happen, according to Lenovo the user
-should suspend or hibernate the laptop (and in the case of battery
-alarms, unplug the AC adapter) to let it cool down. These alarms do
-signal that something is wrong, they should never happen on normal
-operating conditions.
-
-The "extremely hot" alarms are emergencies. According to Lenovo, the
-operating system is to force either an immediate suspend or hibernate
-cycle, or a system shutdown. Obviously, something is very wrong if this
-happens.
-
-Compatibility notes:
-
-ibm-acpi and thinkpad-acpi 0.15 (mainline kernels before 2.6.23) never
-supported the input layer, and sent events over the procfs ACPI event
-interface.
-
-To avoid sending duplicate events over the input layer and the ACPI
-event interface, thinkpad-acpi 0.16 implements a module parameter
-(hotkey_report_mode), and also a sysfs device attribute with the same
-name.
-
-Make no mistake here: userspace is expected to switch to using the input
-layer interface of thinkpad-acpi, together with the ACPI netlink event
-interface in kernels 2.6.23 and later, or with the ACPI procfs event
-interface in kernels 2.6.22 and earlier.
-
-If no hotkey_report_mode module parameter is specified (or it is set to
-zero), the driver defaults to mode 1 (see below), and on kernels 2.6.22
-and earlier, also allows one to change the hotkey_report_mode through
-sysfs. In kernels 2.6.23 and later, where the netlink ACPI event
-interface is available, hotkey_report_mode cannot be changed through
-sysfs (it is read-only).
-
-If the hotkey_report_mode module parameter is set to 1 or 2, it cannot
-be changed later through sysfs (any writes will return -EPERM to signal
-that hotkey_report_mode was locked. On 2.6.23 and later, where
-hotkey_report_mode cannot be changed at all, writes will return -EACCES).
-
-hotkey_report_mode set to 1 makes the driver export through the procfs
-ACPI event interface all hot key presses (which are *also* sent to the
-input layer). This is a legacy compatibility behaviour, and it is also
-the default mode of operation for the driver.
-
-hotkey_report_mode set to 2 makes the driver filter out the hot key
-presses from the procfs ACPI event interface, so these events will only
-be sent through the input layer. Userspace that has been updated to use
-the thinkpad-acpi input layer interface should set hotkey_report_mode to
-2.
-
-Hot key press events are never sent to the ACPI netlink event interface.
-Really up-to-date userspace under kernel 2.6.23 and later is to use the
-netlink interface and the input layer interface, and don't bother at all
-with hotkey_report_mode.
-
-
-Brightness hotkey notes:
-
-Don't mess with the brightness hotkeys in a Thinkpad. If you want
-notifications for OSD, use the sysfs backlight class event support.
-
-The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
-automatically for the cases were userspace has to do something to
-implement brightness changes. When you override these events, you will
-either fail to handle properly the ThinkPads that require explicit
-action to change backlight brightness, or the ThinkPads that require
-that no action be taken to work properly.
-
-
-Bluetooth
----------
-
-procfs: /proc/acpi/ibm/bluetooth
-sysfs device attribute: bluetooth_enable (deprecated)
-sysfs rfkill class: switch "tpacpi_bluetooth_sw"
-
-This feature shows the presence and current state of a ThinkPad
-Bluetooth device in the internal ThinkPad CDC slot.
-
-If the ThinkPad supports it, the Bluetooth state is stored in NVRAM,
-so it is kept across reboots and power-off.
-
-Procfs notes:
-
-If Bluetooth is installed, the following commands can be used:
-
- echo enable > /proc/acpi/ibm/bluetooth
- echo disable > /proc/acpi/ibm/bluetooth
-
-Sysfs notes:
-
- If the Bluetooth CDC card is installed, it can be enabled /
- disabled through the "bluetooth_enable" thinkpad-acpi device
- attribute, and its current status can also be queried.
-
- enable:
- 0: disables Bluetooth / Bluetooth is disabled
- 1: enables Bluetooth / Bluetooth is enabled.
-
- Note: this interface has been superseded by the generic rfkill
- class. It has been deprecated, and it will be removed in year
- 2010.
-
- rfkill controller switch "tpacpi_bluetooth_sw": refer to
- Documentation/rfkill.txt for details.
-
-
-Video output control -- /proc/acpi/ibm/video
---------------------------------------------
-
-This feature allows control over the devices used for video output -
-LCD, CRT or DVI (if available). The following commands are available:
-
- echo lcd_enable > /proc/acpi/ibm/video
- echo lcd_disable > /proc/acpi/ibm/video
- echo crt_enable > /proc/acpi/ibm/video
- echo crt_disable > /proc/acpi/ibm/video
- echo dvi_enable > /proc/acpi/ibm/video
- echo dvi_disable > /proc/acpi/ibm/video
- echo auto_enable > /proc/acpi/ibm/video
- echo auto_disable > /proc/acpi/ibm/video
- echo expand_toggle > /proc/acpi/ibm/video
- echo video_switch > /proc/acpi/ibm/video
-
-NOTE: Access to this feature is restricted to processes owning the
-CAP_SYS_ADMIN capability for safety reasons, as it can interact badly
-enough with some versions of X.org to crash it.
-
-Each video output device can be enabled or disabled individually.
-Reading /proc/acpi/ibm/video shows the status of each device.
-
-Automatic video switching can be enabled or disabled. When automatic
-video switching is enabled, certain events (e.g. opening the lid,
-docking or undocking) cause the video output device to change
-automatically. While this can be useful, it also causes flickering
-and, on the X40, video corruption. By disabling automatic switching,
-the flickering or video corruption can be avoided.
-
-The video_switch command cycles through the available video outputs
-(it simulates the behavior of Fn-F7).
-
-Video expansion can be toggled through this feature. This controls
-whether the display is expanded to fill the entire LCD screen when a
-mode with less than full resolution is used. Note that the current
-video expansion status cannot be determined through this feature.
-
-Note that on many models (particularly those using Radeon graphics
-chips) the X driver configures the video card in a way which prevents
-Fn-F7 from working. This also disables the video output switching
-features of this driver, as it uses the same ACPI methods as
-Fn-F7. Video switching on the console should still work.
-
-UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000
-
-
-ThinkLight control
-------------------
-
-procfs: /proc/acpi/ibm/light
-sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
-
-procfs notes:
-
-The ThinkLight status can be read and set through the procfs interface. A
-few models which do not make the status available will show the ThinkLight
-status as "unknown". The available commands are:
-
- echo on > /proc/acpi/ibm/light
- echo off > /proc/acpi/ibm/light
-
-sysfs notes:
-
-The ThinkLight sysfs interface is documented by the LED class
-documentation, in Documentation/leds/leds-class.txt. The ThinkLight LED name
-is "tpacpi::thinklight".
-
-Due to limitations in the sysfs LED class, if the status of the ThinkLight
-cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
-It is impossible to know if the status returned through sysfs is valid.
-
-
-CMOS/UCMS control
------------------
-
-procfs: /proc/acpi/ibm/cmos
-sysfs device attribute: cmos_command
-
-This feature is mostly used internally by the ACPI firmware to keep the legacy
-CMOS NVRAM bits in sync with the current machine state, and to record this
-state so that the ThinkPad will retain such settings across reboots.
-
-Some of these commands actually perform actions in some ThinkPad models, but
-this is expected to disappear more and more in newer models. As an example, in
-a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
-real, but commands 0 to 2 don't control the mixer anymore (they have been
-phased out) and just update the NVRAM.
-
-The range of valid cmos command numbers is 0 to 21, but not all have an
-effect and the behavior varies from model to model. Here is the behavior
-on the X40 (tpb is the ThinkPad Buttons utility):
-
- 0 - Related to "Volume down" key press
- 1 - Related to "Volume up" key press
- 2 - Related to "Mute on" key press
- 3 - Related to "Access IBM" key press
- 4 - Related to "LCD brightness up" key press
- 5 - Related to "LCD brightness down" key press
- 11 - Related to "toggle screen expansion" key press/function
- 12 - Related to "ThinkLight on"
- 13 - Related to "ThinkLight off"
- 14 - Related to "ThinkLight" key press (toggle ThinkLight)
-
-The cmos command interface is prone to firmware split-brain problems, as
-in newer ThinkPads it is just a compatibility layer. Do not use it, it is
-exported just as a debug tool.
-
-
-LED control
------------
-
-procfs: /proc/acpi/ibm/led
-sysfs attributes: as per LED class, see below for names
-
-Some of the LED indicators can be controlled through this feature. On
-some older ThinkPad models, it is possible to query the status of the
-LED indicators as well. Newer ThinkPads cannot query the real status
-of the LED indicators.
-
-Because misuse of the LEDs could induce an unaware user to perform
-dangerous actions (like undocking or ejecting a bay device while the
-buses are still active), or mask an important alarm (such as a nearly
-empty battery, or a broken battery), access to most LEDs is
-restricted.
-
-Unrestricted access to all LEDs requires that thinkpad-acpi be
-compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled.
-Distributions must never enable this option. Individual users that
-are aware of the consequences are welcome to enabling it.
-
-procfs notes:
-
-The available commands are:
-
- echo '<LED number> on' >/proc/acpi/ibm/led
- echo '<LED number> off' >/proc/acpi/ibm/led
- echo '<LED number> blink' >/proc/acpi/ibm/led
-
-The <LED number> range is 0 to 15. The set of LEDs that can be
-controlled varies from model to model. Here is the common ThinkPad
-mapping:
-
- 0 - power
- 1 - battery (orange)
- 2 - battery (green)
- 3 - UltraBase/dock
- 4 - UltraBay
- 5 - UltraBase battery slot
- 6 - (unknown)
- 7 - standby
- 8 - dock status 1
- 9 - dock status 2
- 10, 11 - (unknown)
- 12 - thinkvantage
- 13, 14, 15 - (unknown)
-
-All of the above can be turned on and off and can be made to blink.
-
-sysfs notes:
-
-The ThinkPad LED sysfs interface is described in detail by the LED class
-documentation, in Documentation/leds/leds-class.txt.
-
-The LEDs are named (in LED ID order, from 0 to 12):
-"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
-"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
-"tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1",
-"tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3",
-"tpacpi::thinkvantage".
-
-Due to limitations in the sysfs LED class, if the status of the LED
-indicators cannot be read due to an error, thinkpad-acpi will report it as
-a brightness of zero (same as LED off).
-
-If the thinkpad firmware doesn't support reading the current status,
-trying to read the current LED brightness will just return whatever
-brightness was last written to that attribute.
-
-These LEDs can blink using hardware acceleration. To request that a
-ThinkPad indicator LED should blink in hardware accelerated mode, use the
-"timer" trigger, and leave the delay_on and delay_off parameters set to
-zero (to request hardware acceleration autodetection).
-
-LEDs that are known not to exist in a given ThinkPad model are not
-made available through the sysfs interface. If you have a dock and you
-notice there are LEDs listed for your ThinkPad that do not exist (and
-are not in the dock), or if you notice that there are missing LEDs,
-a report to ibm-acpi-devel@lists.sourceforge.net is appreciated.
-
-
-ACPI sounds -- /proc/acpi/ibm/beep
-----------------------------------
-
-The BEEP method is used internally by the ACPI firmware to provide
-audible alerts in various situations. This feature allows the same
-sounds to be triggered manually.
-
-The commands are non-negative integer numbers:
-
- echo <number> >/proc/acpi/ibm/beep
-
-The valid <number> range is 0 to 17. Not all numbers trigger sounds
-and the sounds vary from model to model. Here is the behavior on the
-X40:
-
- 0 - stop a sound in progress (but use 17 to stop 16)
- 2 - two beeps, pause, third beep ("low battery")
- 3 - single beep
- 4 - high, followed by low-pitched beep ("unable")
- 5 - single beep
- 6 - very high, followed by high-pitched beep ("AC/DC")
- 7 - high-pitched beep
- 9 - three short beeps
- 10 - very long beep
- 12 - low-pitched beep
- 15 - three high-pitched beeps repeating constantly, stop with 0
- 16 - one medium-pitched beep repeating constantly, stop with 17
- 17 - stop 16
-
-
-Temperature sensors
--------------------
-
-procfs: /proc/acpi/ibm/thermal
-sysfs device attributes: (hwmon "thinkpad") temp*_input
-
-Most ThinkPads include six or more separate temperature sensors but only
-expose the CPU temperature through the standard ACPI methods. This
-feature shows readings from up to eight different sensors on older
-ThinkPads, and up to sixteen different sensors on newer ThinkPads.
-
-For example, on the X40, a typical output may be:
-temperatures: 42 42 45 41 36 -128 33 -128
-
-On the T43/p, a typical output may be:
-temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
-
-The mapping of thermal sensors to physical locations varies depending on
-system-board model (and thus, on ThinkPad model).
-
-http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
-tries to track down these locations for various models.
-
-Most (newer?) models seem to follow this pattern:
-
-1: CPU
-2: (depends on model)
-3: (depends on model)
-4: GPU
-5: Main battery: main sensor
-6: Bay battery: main sensor
-7: Main battery: secondary sensor
-8: Bay battery: secondary sensor
-9-15: (depends on model)
-
-For the R51 (source: Thomas Gruber):
-2: Mini-PCI
-3: Internal HDD
-
-For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
-http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
-2: System board, left side (near PCMCIA slot), reported as HDAPS temp
-3: PCMCIA slot
-9: MCH (northbridge) to DRAM Bus
-10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
- card, under touchpad
-11: Power regulator, underside of system board, below F2 key
-
-The A31 has a very atypical layout for the thermal sensors
-(source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
-1: CPU
-2: Main Battery: main sensor
-3: Power Converter
-4: Bay Battery: main sensor
-5: MCH (northbridge)
-6: PCMCIA/ambient
-7: Main Battery: secondary sensor
-8: Bay Battery: secondary sensor
-
-
-Procfs notes:
- Readings from sensors that are not available return -128.
- No commands can be written to this file.
-
-Sysfs notes:
- Sensors that are not available return the ENXIO error. This
- status may change at runtime, as there are hotplug thermal
- sensors, like those inside the batteries and docks.
-
- thinkpad-acpi thermal sensors are reported through the hwmon
- subsystem, and follow all of the hwmon guidelines at
- Documentation/hwmon.
-
-EXPERIMENTAL: Embedded controller register dump
------------------------------------------------
-
-This feature is not included in the thinkpad driver anymore.
-Instead the EC can be accessed through /sys/kernel/debug/ec with
-a userspace tool which can be found here:
-ftp://ftp.suse.com/pub/people/trenn/sources/ec
-
-Use it to determine the register holding the fan
-speed on some models. To do that, do the following:
- - make sure the battery is fully charged
- - make sure the fan is running
- - use above mentioned tool to read out the EC
-
-Often fan and temperature values vary between
-readings. Since temperatures don't change vary fast, you can take
-several quick dumps to eliminate them.
-
-You can use a similar method to figure out the meaning of other
-embedded controller registers - e.g. make sure nothing else changes
-except the charging or discharging battery to determine which
-registers contain the current battery capacity, etc. If you experiment
-with this, do send me your results (including some complete dumps with
-a description of the conditions when they were taken.)
-
-
-LCD brightness control
-----------------------
-
-procfs: /proc/acpi/ibm/brightness
-sysfs backlight device "thinkpad_screen"
-
-This feature allows software control of the LCD brightness on ThinkPad
-models which don't have a hardware brightness slider.
-
-It has some limitations: the LCD backlight cannot be actually turned
-on or off by this interface, it just controls the backlight brightness
-level.
-
-On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
-has eight brightness levels, ranging from 0 to 7. Some of the levels
-may not be distinct. Later Lenovo models that implement the ACPI
-display backlight brightness control methods have 16 levels, ranging
-from 0 to 15.
-
-For IBM ThinkPads, there are two interfaces to the firmware for direct
-brightness control, EC and UCMS (or CMOS). To select which one should be
-used, use the brightness_mode module parameter: brightness_mode=1 selects
-EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC
-mode with NVRAM backing (so that brightness changes are remembered across
-shutdown/reboot).
-
-The driver tries to select which interface to use from a table of
-defaults for each ThinkPad model. If it makes a wrong choice, please
-report this as a bug, so that we can fix it.
-
-Lenovo ThinkPads only support brightness_mode=2 (UCMS).
-
-When display backlight brightness controls are available through the
-standard ACPI interface, it is best to use it instead of this direct
-ThinkPad-specific interface. The driver will disable its native
-backlight brightness control interface if it detects that the standard
-ACPI interface is available in the ThinkPad.
-
-If you want to use the thinkpad-acpi backlight brightness control
-instead of the generic ACPI video backlight brightness control for some
-reason, you should use the acpi_backlight=vendor kernel parameter.
-
-The brightness_enable module parameter can be used to control whether
-the LCD brightness control feature will be enabled when available.
-brightness_enable=0 forces it to be disabled. brightness_enable=1
-forces it to be enabled when available, even if the standard ACPI
-interface is also available.
-
-Procfs notes:
-
- The available commands are:
-
- echo up >/proc/acpi/ibm/brightness
- echo down >/proc/acpi/ibm/brightness
- echo 'level <level>' >/proc/acpi/ibm/brightness
-
-Sysfs notes:
-
-The interface is implemented through the backlight sysfs class, which is
-poorly documented at this time.
-
-Locate the thinkpad_screen device under /sys/class/backlight, and inside
-it there will be the following attributes:
-
- max_brightness:
- Reads the maximum brightness the hardware can be set to.
- The minimum is always zero.
-
- actual_brightness:
- Reads what brightness the screen is set to at this instant.
-
- brightness:
- Writes request the driver to change brightness to the
- given value. Reads will tell you what brightness the
- driver is trying to set the display to when "power" is set
- to zero and the display has not been dimmed by a kernel
- power management event.
-
- power:
- power management mode, where 0 is "display on", and 1 to 3
- will dim the display backlight to brightness level 0
- because thinkpad-acpi cannot really turn the backlight
- off. Kernel power management events can temporarily
- increase the current power management level, i.e. they can
- dim the display.
-
-
-WARNING:
-
- Whatever you do, do NOT ever call thinkpad-acpi backlight-level change
- interface and the ACPI-based backlight level change interface
- (available on newer BIOSes, and driven by the Linux ACPI video driver)
- at the same time. The two will interact in bad ways, do funny things,
- and maybe reduce the life of the backlight lamps by needlessly kicking
- its level up and down at every change.
-
-
-Volume control (Console Audio control)
---------------------------------------
-
-procfs: /proc/acpi/ibm/volume
-ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC"
-
-NOTE: by default, the volume control interface operates in read-only
-mode, as it is supposed to be used for on-screen-display purposes.
-The read/write mode can be enabled through the use of the
-"volume_control=1" module parameter.
-
-NOTE: distros are urged to not enable volume_control by default, this
-should be done by the local admin only. The ThinkPad UI is for the
-console audio control to be done through the volume keys only, and for
-the desktop environment to just provide on-screen-display feedback.
-Software volume control should be done only in the main AC97/HDA
-mixer.
-
-
-About the ThinkPad Console Audio control:
-
-ThinkPads have a built-in amplifier and muting circuit that drives the
-console headphone and speakers. This circuit is after the main AC97
-or HDA mixer in the audio path, and under exclusive control of the
-firmware.
-
-ThinkPads have three special hotkeys to interact with the console
-audio control: volume up, volume down and mute.
-
-It is worth noting that the normal way the mute function works (on
-ThinkPads that do not have a "mute LED") is:
-
-1. Press mute to mute. It will *always* mute, you can press it as
- many times as you want, and the sound will remain mute.
-
-2. Press either volume key to unmute the ThinkPad (it will _not_
- change the volume, it will just unmute).
-
-This is a very superior design when compared to the cheap software-only
-mute-toggle solution found on normal consumer laptops: you can be
-absolutely sure the ThinkPad will not make noise if you press the mute
-button, no matter the previous state.
-
-The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain
-amplifiers driving the speakers and headphone output, and the firmware
-also handles volume control for the headphone and speakers on these
-ThinkPads without any help from the operating system (this volume
-control stage exists after the main AC97 or HDA mixer in the audio
-path).
-
-The newer Lenovo models only have firmware mute control, and depend on
-the main HDA mixer to do volume control (which is done by the operating
-system). In this case, the volume keys are filtered out for unmute
-key press (there are some firmware bugs in this area) and delivered as
-normal key presses to the operating system (thinkpad-acpi is not
-involved).
-
-
-The ThinkPad-ACPI volume control:
-
-The preferred way to interact with the Console Audio control is the
-ALSA interface.
-
-The legacy procfs interface allows one to read the current state,
-and if volume control is enabled, accepts the following commands:
-
- echo up >/proc/acpi/ibm/volume
- echo down >/proc/acpi/ibm/volume
- echo mute >/proc/acpi/ibm/volume
- echo unmute >/proc/acpi/ibm/volume
- echo 'level <level>' >/proc/acpi/ibm/volume
-
-The <level> number range is 0 to 14 although not all of them may be
-distinct. To unmute the volume after the mute command, use either the
-up or down command (the level command will not unmute the volume), or
-the unmute command.
-
-You can use the volume_capabilities parameter to tell the driver
-whether your thinkpad has volume control or mute-only control:
-volume_capabilities=1 for mixers with mute and volume control,
-volume_capabilities=2 for mixers with only mute control.
-
-If the driver misdetects the capabilities for your ThinkPad model,
-please report this to ibm-acpi-devel@lists.sourceforge.net, so that we
-can update the driver.
-
-There are two strategies for volume control. To select which one
-should be used, use the volume_mode module parameter: volume_mode=1
-selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing
-(so that volume/mute changes are remembered across shutdown/reboot).
-
-The driver will operate in volume_mode=3 by default. If that does not
-work well on your ThinkPad model, please report this to
-ibm-acpi-devel@lists.sourceforge.net.
-
-The driver supports the standard ALSA module parameters. If the ALSA
-mixer is disabled, the driver will disable all volume functionality.
-
-
-Fan control and monitoring: fan speed, fan enable/disable
----------------------------------------------------------
-
-procfs: /proc/acpi/ibm/fan
-sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
- pwm1_enable, fan2_input
-sysfs hwmon driver attributes: fan_watchdog
-
-NOTE NOTE NOTE: fan control operations are disabled by default for
-safety reasons. To enable them, the module parameter "fan_control=1"
-must be given to thinkpad-acpi.
-
-This feature attempts to show the current fan speed, control mode and
-other fan data that might be available. The speed is read directly
-from the hardware registers of the embedded controller. This is known
-to work on later R, T, X and Z series ThinkPads but may show a bogus
-value on other models.
-
-Some Lenovo ThinkPads support a secondary fan. This fan cannot be
-controlled separately, it shares the main fan control.
-
-Fan levels:
-
-Most ThinkPad fans work in "levels" at the firmware interface. Level 0
-stops the fan. The higher the level, the higher the fan speed, although
-adjacent levels often map to the same fan speed. 7 is the highest
-level, where the fan reaches the maximum recommended speed.
-
-Level "auto" means the EC changes the fan level according to some
-internal algorithm, usually based on readings from the thermal sensors.
-
-There is also a "full-speed" level, also known as "disengaged" level.
-In this level, the EC disables the speed-locked closed-loop fan control,
-and drives the fan as fast as it can go, which might exceed hardware
-limits, so use this level with caution.
-
-The fan usually ramps up or down slowly from one speed to another, and
-it is normal for the EC to take several seconds to react to fan
-commands. The full-speed level may take up to two minutes to ramp up to
-maximum speed, and in some ThinkPads, the tachometer readings go stale
-while the EC is transitioning to the full-speed level.
-
-WARNING WARNING WARNING: do not leave the fan disabled unless you are
-monitoring all of the temperature sensor readings and you are ready to
-enable it if necessary to avoid overheating.
-
-An enabled fan in level "auto" may stop spinning if the EC decides the
-ThinkPad is cool enough and doesn't need the extra airflow. This is
-normal, and the EC will spin the fan up if the various thermal readings
-rise too much.
-
-On the X40, this seems to depend on the CPU and HDD temperatures.
-Specifically, the fan is turned on when either the CPU temperature
-climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
-fan is turned off when the CPU temperature drops to 49 degrees and the
-HDD temperature drops to 41 degrees. These thresholds cannot
-currently be controlled.
-
-The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
-certain conditions are met. It will override any fan programming done
-through thinkpad-acpi.
-
-The thinkpad-acpi kernel driver can be programmed to revert the fan
-level to a safe setting if userspace does not issue one of the procfs
-fan commands: "enable", "disable", "level" or "watchdog", or if there
-are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
-set to 1, manual mode) within a configurable amount of time of up to
-120 seconds. This functionality is called fan safety watchdog.
-
-Note that the watchdog timer stops after it enables the fan. It will be
-rearmed again automatically (using the same interval) when one of the
-above mentioned fan commands is received. The fan watchdog is,
-therefore, not suitable to protect against fan mode changes made through
-means other than the "enable", "disable", and "level" procfs fan
-commands, or the hwmon fan control sysfs interface.
-
-Procfs notes:
-
-The fan may be enabled or disabled with the following commands:
-
- echo enable >/proc/acpi/ibm/fan
- echo disable >/proc/acpi/ibm/fan
-
-Placing a fan on level 0 is the same as disabling it. Enabling a fan
-will try to place it in a safe level if it is too slow or disabled.
-
-The fan level can be controlled with the command:
-
- echo 'level <level>' > /proc/acpi/ibm/fan
-
-Where <level> is an integer from 0 to 7, or one of the words "auto" or
-"full-speed" (without the quotes). Not all ThinkPads support the "auto"
-and "full-speed" levels. The driver accepts "disengaged" as an alias for
-"full-speed", and reports it as "disengaged" for backwards
-compatibility.
-
-On the X31 and X40 (and ONLY on those models), the fan speed can be
-controlled to a certain degree. Once the fan is running, it can be
-forced to run faster or slower with the following command:
-
- echo 'speed <speed>' > /proc/acpi/ibm/fan
-
-The sustainable range of fan speeds on the X40 appears to be from about
-3700 to about 7350. Values outside this range either do not have any
-effect or the fan speed eventually settles somewhere in that range. The
-fan cannot be stopped or started with this command. This functionality
-is incomplete, and not available through the sysfs interface.
-
-To program the safety watchdog, use the "watchdog" command.
-
- echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
-
-If you want to disable the watchdog, use 0 as the interval.
-
-Sysfs notes:
-
-The sysfs interface follows the hwmon subsystem guidelines for the most
-part, and the exception is the fan safety watchdog.
-
-Writes to any of the sysfs attributes may return the EINVAL error if
-that operation is not supported in a given ThinkPad or if the parameter
-is out-of-bounds, and EPERM if it is forbidden. They may also return
-EINTR (interrupted system call), and EIO (I/O error while trying to talk
-to the firmware).
-
-Features not yet implemented by the driver return ENOSYS.
-
-hwmon device attribute pwm1_enable:
- 0: PWM offline (fan is set to full-speed mode)
- 1: Manual PWM control (use pwm1 to set fan level)
- 2: Hardware PWM control (EC "auto" mode)
- 3: reserved (Software PWM control, not implemented yet)
-
- Modes 0 and 2 are not supported by all ThinkPads, and the
- driver is not always able to detect this. If it does know a
- mode is unsupported, it will return -EINVAL.
-
-hwmon device attribute pwm1:
- Fan level, scaled from the firmware values of 0-7 to the hwmon
- scale of 0-255. 0 means fan stopped, 255 means highest normal
- speed (level 7).
-
- This attribute only commands the fan if pmw1_enable is set to 1
- (manual PWM control).
-
-hwmon device attribute fan1_input:
- Fan tachometer reading, in RPM. May go stale on certain
- ThinkPads while the EC transitions the PWM to offline mode,
- which can take up to two minutes. May return rubbish on older
- ThinkPads.
-
-hwmon device attribute fan2_input:
- Fan tachometer reading, in RPM, for the secondary fan.
- Available only on some ThinkPads. If the secondary fan is
- not installed, will always read 0.
-
-hwmon driver attribute fan_watchdog:
- Fan safety watchdog timer interval, in seconds. Minimum is
- 1 second, maximum is 120 seconds. 0 disables the watchdog.
-
-To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
-
-To start the fan in a safe mode: set pwm1_enable to 2. If that fails
-with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
-would be the safest choice, though).
-
-
-WAN
----
-
-procfs: /proc/acpi/ibm/wan
-sysfs device attribute: wwan_enable (deprecated)
-sysfs rfkill class: switch "tpacpi_wwan_sw"
-
-This feature shows the presence and current state of the built-in
-Wireless WAN device.
-
-If the ThinkPad supports it, the WWAN state is stored in NVRAM,
-so it is kept across reboots and power-off.
-
-It was tested on a Lenovo ThinkPad X60. It should probably work on other
-ThinkPad models which come with this module installed.
-
-Procfs notes:
-
-If the W-WAN card is installed, the following commands can be used:
-
- echo enable > /proc/acpi/ibm/wan
- echo disable > /proc/acpi/ibm/wan
-
-Sysfs notes:
-
- If the W-WAN card is installed, it can be enabled /
- disabled through the "wwan_enable" thinkpad-acpi device
- attribute, and its current status can also be queried.
-
- enable:
- 0: disables WWAN card / WWAN card is disabled
- 1: enables WWAN card / WWAN card is enabled.
-
- Note: this interface has been superseded by the generic rfkill
- class. It has been deprecated, and it will be removed in year
- 2010.
-
- rfkill controller switch "tpacpi_wwan_sw": refer to
- Documentation/rfkill.txt for details.
-
-
-EXPERIMENTAL: UWB
------------------
-
-This feature is marked EXPERIMENTAL because it has not been extensively
-tested and validated in various ThinkPad models yet. The feature may not
-work as expected. USE WITH CAUTION! To use this feature, you need to supply
-the experimental=1 parameter when loading the module.
-
-sysfs rfkill class: switch "tpacpi_uwb_sw"
-
-This feature exports an rfkill controller for the UWB device, if one is
-present and enabled in the BIOS.
-
-Sysfs notes:
-
- rfkill controller switch "tpacpi_uwb_sw": refer to
- Documentation/rfkill.txt for details.
-
-
-Multiple Commands, Module Parameters
-------------------------------------
-
-Multiple commands can be written to the proc files in one shot by
-separating them with commas, for example:
-
- echo enable,0xffff > /proc/acpi/ibm/hotkey
- echo lcd_disable,crt_enable > /proc/acpi/ibm/video
-
-Commands can also be specified when loading the thinkpad-acpi module,
-for example:
-
- modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
-
-
-Enabling debugging output
--------------------------
-
-The module takes a debug parameter which can be used to selectively
-enable various classes of debugging output, for example:
-
- modprobe thinkpad_acpi debug=0xffff
-
-will enable all debugging output classes. It takes a bitmask, so
-to enable more than one output class, just add their values.
-
- Debug bitmask Description
- 0x8000 Disclose PID of userspace programs
- accessing some functions of the driver
- 0x0001 Initialization and probing
- 0x0002 Removal
- 0x0004 RF Transmitter control (RFKILL)
- (bluetooth, WWAN, UWB...)
- 0x0008 HKEY event interface, hotkeys
- 0x0010 Fan control
- 0x0020 Backlight brightness
- 0x0040 Audio mixer/volume control
-
-There is also a kernel build option to enable more debugging
-information, which may be necessary to debug driver problems.
-
-The level of debugging information output by the driver can be changed
-at runtime through sysfs, using the driver attribute debug_level. The
-attribute takes the same bitmask as the debug module parameter above.
-
-
-Force loading of module
------------------------
-
-If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
-the module parameter force_load=1. Regardless of whether this works or
-not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
-
-
-Sysfs interface changelog:
-
-0x000100: Initial sysfs support, as a single platform driver and
- device.
-0x000200: Hot key support for 32 hot keys, and radio slider switch
- support.
-0x010000: Hot keys are now handled by default over the input
- layer, the radio switch generates input event EV_RADIO,
- and the driver enables hot key handling by default in
- the firmware.
-
-0x020000: ABI fix: added a separate hwmon platform device and
- driver, which must be located by name (thinkpad)
- and the hwmon class for libsensors4 (lm-sensors 3)
- compatibility. Moved all hwmon attributes to this
- new platform device.
-
-0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
- support. If you must, use it to know you should not
- start a userspace NVRAM poller (allows to detect when
- NVRAM is compiled out by the user because it is
- unneeded/undesired in the first place).
-0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
- and proper hotkey_mask semantics (version 8 of the
- NVRAM polling patch). Some development snapshots of
- 0.18 had an earlier version that did strange things
- to hotkey_mask.
-
-0x020200: Add poll()/select() support to the following attributes:
- hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason
-
-0x020300: hotkey enable/disable support removed, attributes
- hotkey_bios_enabled and hotkey_enable deprecated and
- marked for removal.
-
-0x020400: Marker for 16 LEDs support. Also, LEDs that are known
- to not exist in a given model are not registered with
- the LED sysfs class anymore.
-
-0x020500: Updated hotkey driver, hotkey_mask is always available
- and it is always able to disable hot keys. Very old
- thinkpads are properly supported. hotkey_bios_mask
- is deprecated and marked for removal.
-
-0x020600: Marker for backlight change event support.
-
-0x020700: Support for mute-only mixers.
- Volume control in read-only mode by default.
- Marker for ALSA mixer support.