Given the right combination of ThinkPad and X.org, just reading the
video output control state is enough to hard-crash X.org.

Until the day I somehow find out a model or BIOS cut date to not
provide this feature to ThinkPads that can do video switching through
X RandR, change permissions so that only processes with CAP_SYS_ADMIN
can access any sort of video output control state.

This bug could be considered a local DoS I suppose, as it allows any
non-privledged local user to cause some versions of X.org to
hard-crash some ThinkPads.
Reported-by: NJidanni <jidanni@jidanni.org>
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: stable@kernel.org

Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Take advantage of the new events capabilities of the backlight class to
notify userspace of backlight changes.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add the basic ALSA mixer functionality.  The mixer is event-driven,
and will work fine on IBM ThinkPads.  I expect Lenovo ThinkPads will
cause some trouble with the event interface.

Heavily based on work by Lorne Applebaum <lorne.applebaum@gmail.com>
and ideas from Matthew Garrett <mjg@redhat.com>.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Lorne Applebaum <lorne.applebaum@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Disable volume control by default.  It can be enabled at module load
time by a module parameter (volume_control=1).

The audio control mixer that thinkpad-acpi interacts with is fully
functional without any drivers, and operated by hotkeys.

The idea behind the console audio control is that the human operator
is the only one that can interact with it.  The ThinkVantage suite in
Windows does not allow any software-based overrides, and only does OSD
(on-screen-display) functions.

The Linux driver will, with the addition of the ALSA interface, try to
follow and enforce the ThinkVantage UI design:

The user is supposed to use the keyboard hotkeys to interact with the
console audio control.  The kernel and the desktop environment is
supposed to cooperate to provide proper user feedback through
on-screen-display functions.

Distros are urged to not to enable volume control by default.
Enabling this must be a local admin's decision.  This is the reason
why there is no Kconfig option.

Keep in mind that all ThinkPads have a normal, main mixer (AC97 or
HDA) for regular software-based audio control.  We are not talking
about that mixer here.

Advanced users are, of course, free to enable volume control and do as
they please.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Lorne Applebaum <lorne.applebaum@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Lenovo removed the extra mixer since the T61 and thereabouts.
Newer Lenovo models only have the mute gate function, and leave
the volume control to the HDA mixer.

Until a way to automatically query the firmware about its audio
control capabilities is discovered (there might not be any), use a
white/black list.

We will likely need to ask T60 (old and new model) and Z60/Z61 users
whether they have volume control to populate the black/white list.
Meanwhile, provide a volume_capabilities parameter that can be used to
override the defaults.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Lorne Applebaum <lorne.applebaum@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

I don't trust the coupled EC writes and SMI calls the current volume
control code does very much, although it is exactly what the IBM DSDTs
seem to do (they never do more than a single step though).

Change the driver to stop issuing SMIs, and just drive the EC directly
to the desired level (DSDTs seem to confirm this will work even on
very old models like the 570 and 600e/x).

We checkpoint directly to NVRAM (this can be turned off) at
suspend/shutdown/driver unload, which from what I can see in tbp,
should also work on every ThinkPad.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Lorne Applebaum <lorne.applebaum@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Take advantage of the new events capabilities of the backlight class to
notify userspace of backlight changes.

This depends on "backlight: Allow drivers to update the core, and
generate events on changes", by Matthew Garrett.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Update the HKEY event driver to:

1. Handle better the second-gen firmware, which has no HKEY mask
   support but does report FN+F3, FN+F4 and FN+F12 without the need
   for NVRAM polling.

   a) always make the mask-related attributes available in sysfs;
   b) use DMI quirks to detect the second-gen firmware;
   c) properly report that FN+F3, FN+F4 and FN+F12 are enabled,
      and available even on mask-less second-gen firmware;

2. Decouple the issuing of hotkey events towards userspace from
   their reception from the firmware.  ALSA mixer and brightness
   event reporting support will need this feature.

3. Clean up the mess in the hotkey driver a great deal.  It is
   still very convoluted, and wants a full refactoring into a
   proper event API interface, but that is not going to happen
   today.

4. Fully reset firmware interface on resume (restore hotkey
   mask and status).

5. Stop losing polled events for no good reason when changing the
   mask and poll frequencies.  We will still lose them when the
   hotkey_source_mask is changed, as well as any that happened
   between driver suspend and driver resume.

The hotkey subdriver now has the notion of user-space-visible hotkey
event mask, as well as of the set of "hotkey" events the driver needs
(because brightness/volume change reports are not just keypress
reports in most ThinkPad models).

With this rewrite, the ABI level is bumped to 0x020500 should
userspace need to know it is dealing with the updated hotkey
subdriver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

HKEY event 0x5010 is useless to us: old ThinkPads don't issue it.  Newer
ThinkPads won't issue it anymore.  And all ThinkPads issue 0x1010 and
0x1011 events.

Just silently drop it instead of sending it to userspace.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

echo "reset" > /proc/acpi/ibm/hotkey should do something non-useless,
so instead of setting it to Fn+F2, Fn+F3, Fn+F5, set it to
hotkey_recommended_mask.

It is not like it will survive for much longer, anyway.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Some analysis of the ACPI DSDTs shows that the HKEY pre-enabled mask
is always 0x80c (FN+F3,FN+F4 and FN+F12), which are the hotkeys that
the second gen of HKEY firmware supported (the first gen didn't report
any hotkeys, the second reported these tree hotkeys but had no mask
support, and the third added mask support).

So, this is probably some sort of backwards compatibility with older
versions of the IBM ThinkVantage suite.  We have no use for that, and
I know of exactly ZERO users of that attribute, anyway.  Start the
process of getting rid of it.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

The standard ACPI dock driver can handle the hotplug bays and docks of
the ThinkPads just fine (including batteries) as of 2.6.27, and the
code in thinkpad-acpi for the dock and bay subdrivers is currently
broken anyway...

Userspace needs some love to support the two-stage ejection nicely,
but it is simple enough to do through udev rules (you don't even need
HAL) so this wouldn't justify fixing the dock and bay subdrivers,
either.

That leaves warm-swap bays (_EJ3) support for thinkpad-acpi, as well
as support for the weird dock of the model 570, but since such support
has never left the "experimental" stage, it is also not a strong
enough reason to find a way to fix this code.

Users of ThinkPads with warm-swap bays are urged to request that _EJ3
support be added to the regular ACPI dock driver, if such feature is
indeed useful for them.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Support reading the tachometer of the auxiliary fan of a X60/X61.

It was found out by sheer luck, that bit 0 of EC register 0x31
(formely HBRV) selects which fan is active for tachometer readings
through EC 0x84/0x085: 0 for fan1, 1 for fan2.

Many thanks to Christoph Kl??nter, to Whoopie, and to weasel, who
helped confirm that behaviour.

Fan control through EC HFSP applies to both fans equally, regardless
of the state of bit 0 of EC 0x31.  That matches the way the DSDT uses
HFSP.

In order to better support the secondary fan, export a second
tachometer over hwmon, and add defensive measures to make sure we are
reading the correct tachometer.

Support for the second fan is whitelist-based, as I have not found
anything obvious to look for in the DSDT to detect the presence of
the second fan.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Forcing thinkpad-acpi to do EC-based brightness control (HBRV) on a
X61 has very... interesting effects, instead of doing nothing (since
it doesn't have EC-based backlight control), it causes "weirdness" in
the fan tachometer readings, for example.

This means the EC register that used to be HBRV has been reused by
Lenovo for something else, but they didn't remove it from the DSDT.

Make sure the documentation reflects this data, and forbid the user
from forcing the driver to access HBRV on Lenovo ThinkPads.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add support for extra LEDs on recent ThinkPads, and avoid registering
with the led class the LEDs which are not available for a given
ThinkPad model.

All non-restricted LEDs are always available through the procfs
interface, as the firmware doesn't care if an attempt is made to
access an invalid LED.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Fix various typos in documentation txts.
Signed-off-by: NMatt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Plenty of high-profile changes, so it deserves a new version number.

Features added since 0.22:
 *  Restrict unsafe LEDs
 *  New race-less brightness control strategy for IBM ThinkPads
 *  Disclose TGID of driver access from userspace (debug)
 *  Warn when deprecated functions are used

Other changes:
 *  Better debug messages in some subdrivers
 *  Removed "hotkey disable" support, since it breaks the driver
 *  Dropped "ibm-acpi" alias
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Refactor and redesign the brightness control backend...

In order to fix bugzilla #11750...

Add a new brightness control mode: support direct NVRAM checkpointing
of the backlight level (i.e. store directly to NVRAM without the need
for UCMS calls), and use that together with the EC-based control.
Disallow UCMS+EC, thus avoiding races with the SMM firmware.

Switch the models that define HBRV (EC Brightness Value) in the DSDT
to the new mode.  These are: T40-T43, R50-R52, R50e, R51e, X31-X41.

Change the default for all other IBM ThinkPads to UCMS-only.  The
Lenovo models already default to UCMS-only.
Reported-by: NAlexey Fisher <bug-track@fisher-privat.net>
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Enhance debugging messages for the fan subdriver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Enhance debugging messages for the hotkey subdriver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Enhance debugging messages for all rfkill subdrivers in thinkpad-acpi.

Also, log a warning if the deprecated sysfs attributes are in use.
These attributes are going to be removed sometime in 2010.

There is an user-visible side-effect: we now coalesce attempts to
enable/disable bluetooth or WWAN in the procfs interface, instead of
hammering the firmware with multiple requests.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Some of the ThinkPad LEDs indicate critical conditions that can cause
data loss or cause hardware damage when ignored (e.g. force-ejecting
a powered up bay; ignoring a failing battery, or empty battery; force-
undocking with the dock buses still active, etc).

On almost all ThinkPads, LED access is write-only, and the firmware
usually does fire-and-forget signaling on them, so you effectively
lose whatever message the firmware was trying to convey to the user
when you override the LED state, without any chance to restore it.

Restrict access to all LEDs that can convey important alarms, or that
could mislead the user into incorrectly operating the hardware.  This
will make the Lenovo engineers less unhappy about the whole issue.

Allow users that really want it to still control all LEDs, it is the
unaware user that we have to worry about.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

The HKEY disable functionality basically cripples the entire event
model of the ThinkPad firmware and of the thinkpad-acpi driver.
Remove this functionality from the driver.  HKEY must be enabled at
all times while thinkpad-acpi is loaded, and disabled otherwise.

For sysfs, according to the sysfs ABI and the thinkpad-acpi sysfs
rules of engagement, we will just remove the attributes.  This will be
done in two stages: disable their function now, after two kernel
releases, remove the attributes.

For procfs, we call WARN().  If nothing triggers it, I will simply
remove the enable/disable commands entirely in the future along with
the sysfs attributes.

I don't expect much, if any fallout from this.  There really isn't any
reason to mess with hotkey_enable or with the enable/disable commands
to /proc/acpi/ibm/hotkey, and this has been true for years...
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a debug helper that discloses the TGID of the userspace task
attempting to access the driver.  This is highly useful when dealing
with bug reports, since often the user has no idea that some userspace
application is accessing thinkpad-acpi...

Also add a helper to log warnings about sysfs attributes that are
deprecated.

Use the new helpers to issue deprecation warnings for bluetooth_enable
and wwan_enabled, that have been deprecated for a while, now.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Some cleanups to the documentation of the driver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

It is about time to bump up the version.

Features added since 0.21:  fan suspend/resume support, preserve radio
state across power off (for some radio types), built-in UWB radio
rfkill support and thermal alarm events support.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add rfkill support for USB UWB radio devices on very recent ThinkPad
laptop models.

The new subdriver is moslty a trimmed down copy of the wwan subdriver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Update documentation to reflect the new location of the
thinkpad-acpi driver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

It is always "an" if there is a vowel _spoken_ (not written).
So it is:
"an hour" (spoken vowel)
but
"a uniform" (spoken 'j')
Signed-off-by: NFrederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The WWAN radio control has been working well for over three years,
and is no longer experimental.
Signed-off-by: NJeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>

rfkill support deserves a new version checkpoint...
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>

Add a read/write rfkill interface to the bluetooth radio switch on the
bluetooth submodule, and one for the wireless wan radio switch to the wan
submodule.

Since rfkill does care for when a switch changes state, use WLSW
notifications to also check if the WWAN or Bluetooth switches did not
change state (due to them being slaves of WLSW in firmware/hardware, but
that reality not being always properly exported by the thinkpad firmware).
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Ivo van Doorn <IvDoorn@gmail.com>
Cc: John W. Linville <linville@tuxdriver.com>

Rename SW_RADIO to SW_RFKILL_ALL in thinkpad-acpi code and docs, following
5adad013 "Input: rename SW_RADIO to
SW_RFKILL_ALL".
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Full LED sysfs support, and the rest of the assorted minor fixes and
enhancements are a good reason to checkpoint a new version...
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Change all occourences of the "led" word to full uppercase in user
documentation.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a sysfs led class interface to the led subdriver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a sysfs led class interface to the thinklight (light subdriver).
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NLen Brown <len.brown@intel.com>

Unfortunately, a lot of stuff in the kernel has size limitations, so
"thinkpad-acpi" ends up eating up too much real estate.  We were using
"tpacpi" in symbols already, but this shorthand was not visible to
userland.

Document that the driver will use tpacpi as a short hand where necessary,
and use it to name the kernel thread for NVRAM polling (now named
"ktpacpi_nvramd").

Also, register a module alias with the shorthand.  One can refer to the
module using the shorthand name.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>