ThinkPad ACPI Extras Driver
- Version 0.14
- April 21st, 2007
+ Version 0.17
+ October 04th, 2007
Borislav Deianov <borislav@users.sf.net>
- Henrique de Moraes Holschuh <hmh@hmh.eng.br>
- http://ibm-acpi.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
as a driver attribute (see below).
Sysfs driver attributes are on the driver's sysfs attribute space,
-for 2.6.20 this is /sys/bus/platform/drivers/thinkpad-acpi/.
+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 driver's sysfs attribute space,
-for 2.6.20 this is /sys/devices/platform/thinkpad-acpi/.
+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".
Driver version
--------------
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_*
-Without this driver, only the Fn-F4 key (sleep button) generates an
-ACPI event. With the driver loaded, the hotkey feature enabled and the
-mask set (see below), the various hot keys generate ACPI events in the
-following format:
+In a ThinkPad, the ACPI HKEY handler is responsible for comunicating
+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 hot key feature automatically when loaded. The
+feature can later be disabled and enabled back at runtime. The driver
+will also restore the hot key feature to its previous state and mask
+when it is unloaded.
+
+When the hotkey feature is enabled and the hot key mask is set (see
+below), the driver will report HKEY events in the following format:
ibm/hotkey HKEY 00000080 0000xxxx
-The last four digits vary depending on the key combination pressed.
-All labeled Fn-Fx key combinations generate distinct events. In
-addition, the lid microswitch and some docking station buttons may
-also generate such events.
-
-The bit mask allows some control over which hot keys generate ACPI
-events. 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. Most recent ThinkPad models honor the
-following bits (assuming the hot keys feature has been enabled):
-
- key bit behavior when set behavior when unset
-
- Fn-F3 always generates ACPI event
- Fn-F4 always generates ACPI event
- Fn-F5 0010 generate ACPI event enable/disable Bluetooth
- Fn-F7 0040 generate ACPI event switch LCD and external display
- Fn-F8 0080 generate ACPI event expand screen or none
- Fn-F9 0100 generate ACPI event none
- Fn-F12 always generates ACPI event
-
-Some models do not support all of the above. For example, the T30 does
-not support Fn-F5 and Fn-F9. Other models do not support the mask at
-all. On those models, hot keys cannot be controlled individually.
-
-Note that enabling ACPI events for some keys prevents their default
-behavior. For example, if events for Fn-F5 are enabled, that key will
-no longer enable/disable Bluetooth by itself. This can still be done
-from an acpid handler for the ibm/hotkey event.
-
-Note also that not all Fn key combinations are supported through
-ACPI. For example, on the X40, the brightness, volume and "Access IBM"
-buttons do not generate ACPI events even with this driver. They *can*
-be used through the "ThinkPad Buttons" utility, see
-http://www.nongnu.org/tpb/
+Some of these events refer to hot key presses, but not all.
+
+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, and in those
+models, hot keys cannot be controlled individually. The behaviour of
+the mask is, therefore, higly dependent on the ThinkPad model.
+
+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.
+
+Note also that not all Fn key combinations are supported through ACPI.
+For example, on the X40, the brightness, volume and "Access IBM" buttons
+do not generate ACPI events even with this driver. They *can* be used
+through the "ThinkPad Buttons" utility, see http://www.nongnu.org/tpb/
procfs notes:
echo enable > /proc/acpi/ibm/hotkey -- enable the hot keys feature
echo disable > /proc/acpi/ibm/hotkey -- disable the hot keys feature
- echo 0xffff > /proc/acpi/ibm/hotkey -- enable all possible hot keys
- echo 0x0000 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
- ... any other 4-hex-digit mask ...
+ 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 original mask
sysfs notes:
key feature status will be restored to this value.
0: hot keys were disabled
- 1: hot keys were enabled
+ 1: hot keys were enabled (unusual)
hotkey_bios_mask:
Returns the hot keys mask when thinkpad-acpi was loaded.
1: enables the hot keys feature / feature enabled
hotkey_mask:
- bit mask to enable ACPI event generation for each hot
- key (see above). Returns the current status of the hot
- keys mask, and allows one to modify it.
+ bit mask to enable driver-handling and 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.
+
+ hotkey_radio_sw:
+ if the ThinkPad has a hardware radio switch, this
+ attribute will read 0 if the switch is in the "radios
+ disabled" postition, and 1 if the switch is in the
+ "radios enabled" position.
+
+ 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).
+
+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
+ Lenovo: battery
+
+0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
+ semanthics, i.e. sleep-to-RAM).
+ It is always generate some kind
+ of event, either the hot key
+ event or a 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
+
+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+F4 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.
+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.
+
+Non hot-key ACPI HKEY event map:
+0x5001 Lid closed
+0x5002 Lid opened
+0x7000 Radio Switch may have changed state
+
+The above events are not propagated by the driver, except for legacy
+compatibility purposes when hotkey_report_mode is set to 1.
+
+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 -EACES).
+
+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.
Bluetooth
procfs: /proc/acpi/ibm/cmos
sysfs device attribute: cmos_command
-This feature is used internally by the ACPI firmware to control the
-ThinkLight on most newer ThinkPad models. It may also control LCD
-brightness, sounds volume and more, but only on some models.
+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 - no effect but tpb reports "Volume down"
- 1 - no effect but tpb reports "Volume up"
- 2 - no effect but tpb reports "Mute on"
- 3 - simulate pressing the "Access IBM" button
- 4 - LCD brightness up
- 5 - LCD brightness down
- 11 - toggle screen expansion
- 12 - ThinkLight on
- 13 - ThinkLight off
- 14 - no effect but tpb reports ThinkLight status change
+ 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 pess
+ 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.
+in newer ThinkPads it is just a compatibility layer. Do not use it, it is
+exported just as a debug tool.
LED control -- /proc/acpi/ibm/led
---------------------------------
-------------------
procfs: /proc/acpi/ibm/thermal
-sysfs device attributes: (hwmon) 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 it has experimental support for up to sixteen different
-sensors on newer ThinkPads.
+sysfs device attributes: (hwmon "thinkpad") temp*_input
-EXPERIMENTAL: The 16-sensors feature is marked EXPERIMENTAL because the
-implementation directly accesses hardware registers and may not work as
-expected. USE WITH CAUTION! To use this feature, you need to supply the
-experimental=1 parameter when loading the module. When EXPERIMENTAL
-mode is enabled, reading the first 8 sensors on newer ThinkPads will
-also use an new experimental thermal sensor access mode.
+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
-EXPERIMENTAL: On the T43/p, a typical output may be:
+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
2: System board, left side (near PCMCIA slot), reported as HDAPS temp
3: PCMCIA slot
9: MCH (northbridge) to DRAM Bus
-10: ICH (southbridge), under Mini-PCI card, under touchpad
+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
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, and in many ThinkPad models, the "dim while on battery"
-functionality will be enabled by the BIOS when this interface is used, and
-cannot be controlled.
-
-The backlight control has eight levels, ranging from 0 to 7. Some of the
-levels may not be distinct.
+It has some limitations: the LCD backlight cannot be actually turned on or
+off by this interface, and in many ThinkPad models, the "dim while on
+battery" functionality will be enabled by the BIOS when this interface is
+used, and cannot be controlled.
+
+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.
+
+There are two interfaces to the firmware for direct brightness control,
+EC and CMOS. To select which one should be used, use the
+brightness_mode module parameter: brightness_mode=1 selects EC mode,
+brightness_mode=2 selects CMOS mode, brightness_mode=3 selects both EC
+and CMOS. The driver tries to autodetect which interface to use.
+
+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.
+
+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:
Sysfs notes:
-The interface is implemented through the backlight sysfs class, which is poorly
-documented at this time.
+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:
+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.
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.
+ 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.
+ 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.
Volume control -- /proc/acpi/ibm/volume
---------------------------------------------------------
procfs: /proc/acpi/ibm/fan
-sysfs device attributes: (hwmon) fan_input, pwm1, pwm1_enable
+sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
+ pwm1_enable
+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"
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 varios thermal readings
+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.
which can take up to two minutes. May return rubbish on older
ThinkPads.
-driver attribute fan_watchdog:
+hwmon driver attribute fan_watchdog:
Fan safety watchdog timer interval, in seconds. Minimum is
1 second, maximum is 120 seconds. 0 disables the watchdog.
Enabling debugging output
-------------------------
-The module takes a debug paramater which can be used to selectively
+The module takes a debug parameter which can be used to selectively
enable various classes of debugging output, for example:
modprobe ibm_acpi debug=0xffff
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.
git.openpandora.org / pandora-kernel.git / blobdiff