ThinkPad ACPI Extras Driver
- Version 0.23
- April 10th, 2009
+ Version 0.24
+ December 11th, 2009
Borislav Deianov <borislav@users.sf.net>
Henrique de Moraes Holschuh <hmh@hmh.eng.br>
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, highly dependent on the ThinkPad model.
+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.
+Bluetooth by itself in firmware.
-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/
+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:
1: does nothing
hotkey_mask:
- bit mask to enable driver-handling (and depending on
+ 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.
- Note: when NVRAM polling is active, the firmware mask
- will be different from the value returned by
- hotkey_mask. The driver will retain enabled bits for
- hotkeys that are under NVRAM polling even if the
- firmware refuses them, and will not set these bits on
- the firmware hot key mask.
-
hotkey_all_mask:
bit mask that should enable event reporting for all
supported hot keys, when echoed to hotkey_mask above.
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_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
based on the capabilities reported by the ACPI firmware,
but it can be overridden at runtime.
- Hot keys whose bits are set in both hotkey_source_mask
- and also on hotkey_mask are polled for in NVRAM. Only a
- few hot keys are available through CMOS NVRAM polling.
+ 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,
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.
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
The above events are never propagated by the driver.
0x4003 Undocked (see 0x2x04), can sleep again
0x500B Tablet pen inserted into its storage bay
0x500C Tablet pen removed from its storage bay
-0x5010 Brightness level changed (newer Lenovo BIOSes)
The above events are propagated by the driver.
Brightness hotkey notes:
-These are the current sane choices for brightness key mapping in
-thinkpad-acpi:
-
-For IBM and Lenovo models *without* ACPI backlight control (the ones on
-which thinkpad-acpi will autoload its backlight interface by default,
-and on which ACPI video does not export a backlight interface):
-
-1. Don't enable or map the brightness hotkeys in thinkpad-acpi, as
- these older firmware versions unfortunately won't respect the hotkey
- mask for brightness keys anyway, and always reacts to them. This
- usually work fine, unless X.org drivers are doing something to block
- the BIOS. In that case, use (3) below. This is the default mode of
- operation.
-
-2. Enable the hotkeys, but map them to something else that is NOT
- KEY_BRIGHTNESS_UP/DOWN or any other keycode that would cause
- userspace to try to change the backlight level, and use that as an
- on-screen-display hint.
-
-3. IF AND ONLY IF X.org drivers find a way to block the firmware from
- automatically changing the brightness, enable the hotkeys and map
- them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN, and feed that to
- something that calls xbacklight. thinkpad-acpi will not be able to
- change brightness in that case either, so you should disable its
- backlight interface.
-
-For Lenovo models *with* ACPI backlight control:
-
-1. Load up ACPI video and use that. ACPI video will report ACPI
- events for brightness change keys. Do not mess with thinkpad-acpi
- defaults in this case. thinkpad-acpi should not have anything to do
- with backlight events in a scenario where ACPI video is loaded:
- brightness hotkeys must be disabled, and the backlight interface is
- to be kept disabled as well. This is the default mode of operation.
+Don't mess with the brightness hotkeys in a Thinkpad. If you want
+notifications for OSD, use the sysfs backlight class event support.
-2. Do *NOT* load up ACPI video, enable the hotkeys in thinkpad-acpi,
- and map them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN. Process
- these keys on userspace somehow (e.g. by calling xbacklight).
+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
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.
its level up and down at every change.
-Volume control -- /proc/acpi/ibm/volume
----------------------------------------
+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.
-This feature allows volume control on ThinkPad models which don't have
-a hardware volume knob. The available commands are:
+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 15 although not all of them may be
-distinct. The unmute the volume after the mute command, use either the
-up or down command (the level command will not unmute the volume).
-The current volume level and mute state is shown in the file.
+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 ALSA mixer interface to this feature is still missing, but patches
-to add it exist. That problem should be addressed in the not so
-distant future.
+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
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.
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.
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff