Newer Lenovo BIOSes support the standard ACPI backlight brightness
interface (_BCM, _BQC, _BCL).  It should be used instead of the native
thinkpad backlight brightness control interface when possible.

This patch disables the native brightness support in the driver by default
when we detect that the standard ACPI interface is available.  The local
admin can still enable it using the module parameter "brightness_enable".

Note that we need to detect the standard ACPI backlight interface only in
boxes for which we would load the native backlight interface in the first
place, and that no ThinkPad BIOS has _BCL but misses the other methods, so
the detection routines can be really simple.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a "brightness_enable" module parameter that allows the local admin to
force the backlight support to not be enabled.

It can also be used to force the backlight support to be enabled, but that
is currently a no-op as the backlight support is enabled by default when
available.  This will be changed by a different patch.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Lenovo ThinkPads often have 16 brightness levels in EC, and not just eight
levels like older ThinkPads.  They also have standard ACPI backlight
brightness control.

We detect the number of brightness levels by the presence of a BCLL package
with 16 entries.  If BCLL is not there, we assume eight levels (Z6*).  If
it is there, but it doesn't have 16 entries, we assume eight levels (T60).
Otherwise we assume sixteen levels (T61, X61, etc).

We don't use _BCL because it can have side-effects in thinkpads.  Thanks to
Thomas Renninger <trenn@suse.de> for notifying me of this potential
problem.

Using the standard ACPI backlight brightness control *instead* of the
native thinkpad backlight control is a better idea, though.  A different
patch will take care of this.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.

Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: NMatt LaPlante <kernel1@cyberdogtech.com>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>

Spelling fixes in Documentation/.
Signed-off-by: NSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>

Use a separate platform device and driver ("thinkpad_hwmon") to attach
hwmon attributes and class, and add a name attribute of "thinkpad" to
it, which defines the hwmon device name for libsensors4.

This makes thinkpad-acpi compatible with libsensors4 from lm-sensors, and
the platform driver and device split will make it much easier to separate
hwmon functionality into its own module later on.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Name it thinkpad-acpi version 0.16 to avoid any confusion with some 0.15
thinkpad-acpi development snapshots and backports that had input layer
support, but no hotkey_report_mode support.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Revert new 2.6.23 CONFIG_THINKPAD_ACPI_INPUT_ENABLED Kconfig option because
it would create a legacy we don't want to support.

CONFIG_THINKPAD_ACPI_INPUT_ENABLED was added to try to fix an issue that is
now moot with the addition of the netlink ACPI event report interface to
the ACPI core.

Now that ACPI core can send events over netlink, we can use a different
strategy to keep backwards compatibility with older userspace, without the
need for the CONFIG_THINKPAD_ACPI_INPUT_ENABLED games.  And it arrived
before CONFIG_THINKPAD_ACPI_INPUT_ENABLED made it to a stable mainline
kernel, even, which is Good.

This patch is in sync with some changes to thinkpad-acpi backports, that
will keep things sane for userspace across different combinations of kernel
versions, thinkpad-acpi backports (or the lack thereof), and userspace
capabilities:

Unless a module parameter is used, thinkpad-acpi will now behave in such a
way that it will work well (by default) with userspace that still uses only
the old ACPI procfs event interface and doesn't care for thinkpad-acpi
input devices.

It will also always work well with userspace that has been updated to use
both the thinkpad-acpi input devices, and ACPI core netlink event
interface, regardless of any module parameter.

The module parameter was added to allow thinkpad-acpi to work with
userspace that has been partially updated to use thinkpad-acpi input
devices, but not the new ACPI core netlink event interface.  To use this
mode of hot key reporting, one has to specify the hotkey_report_mode=2
module parameter.

The thinkpad-acpi driver exports the value of hotkey_report_mode through
sysfs, as well.  thinkpad-acpi backports to older kernels, that do not
support the new ACPI core netlink interface, have code to allow userspace
to switch hotkey_report_mode at runtime through sysfs.  This capability
will not be provided in mainline thinkpad-acpi as it is not needed there.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Richard Hughes <hughsient@gmail.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

The documentation used "thinkpad-acpi" to refer to the directories in
sysfs, while it should have been using "thinkpad_acpi".  Thanks to Hugh
Dickins for the error report.

I wish I could just call the module and everything else by the proper
name with the "-", instead of using these ugly translations to "_".
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Name it thinkpad-acpi version 0.15.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Reading the 16 thermal sensors directly from the EC has been stable for
about one year, in all supported ThinkPad models.  Remove its
"experimental" label.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Lenovo ThinkPads have a slightly different key map layout from IBM
ThinkPads (fn+f2 and fn+f3 are swapped).  Knowing which one we are dealing
with, we can properly set a few more hot keys up by default.

Also, export the correct vendor in the input device, as that information
might be useful to userspace.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

It appears that Lenovo decided to break the EC brightness control interface
in a weird way in their latest BIOSes.  Fortunately, the old CMOS NVRAM
interface works just fine in such BIOSes.

Add a module parameter that allows the user to select which strategy to use
for brightness control: EC, NVRAM, or both.  By default, do both (which is
the way thinkpad-acpi used to work until now) on IBM ThinkPads, and use
NVRAM only on Lenovo ThinkPads.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

The change in the way hotkey events are handled by default, and the use of
the input layer for the hotkey events are important enough features to
warrant increasing the major field of the sysfs interface version.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Make the input layer the default way to deal with thinkpad-acpi hot keys,
but add a kernel config option to retain the old way of doing things.

This means we map a lot more keys to useful stuff by default, and also that
we enable hot key handling by default on driver load (like Windows does).

The documentation for proper use of this resource is also updated.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Richard Hughes <hughsient@gmail.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add input device support to the hotkey subdriver.

Hot keys that have a valid keycode mapping are reported through the input
layer if the input device is open.  Otherwise, they will be reported as
ACPI events, as they were before.

Scan codes are reported (using EV_MSC MSC_SCAN events) along with EV_KEY
KEY_UNKNOWN events.

For backwards compatibility purposes, hot keys that used to be reported
through ACPI events are not mapped to anything meaningful by default.
Userspace is supposed to remap them if it wants to use the input device for
hot key reporting.

This patch is based on a patch by Richard Hughes <hughsient@gmail.com>.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Richard Hughes <hughsient@gmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

The CMOS set of commands is often just used to keep the CMOS NVRAM in sync
with whatever the ACPI BIOS has been doing in modern ThinkPads.  In older
ThinkPads, it actually carried out real actions.  Document this.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

The change in the size of the hotkey mask, the hability to report the keys
that use the higher bits, and the addition of the hotkey_radio_sw attribute
are important enough features to warrant increasing the minor field of the
sysfs interface version.

Also, document a bit better how and when the thinkpad-acpi sysfs interface
version will be updated.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Some ThinkPad models, notably the T60 and X60, have a slider switch to
enable and disable the radios.  The switch has the capability of
force-disabling the radios in hardware on most models, and it is supposed
to affect all radios (WLAN, WWAN, BlueTooth).

Export the switch state as a sysfs attribute, on ThinkPads where it is
available.

Thanks to Henning Schild for asking for this feature, and for tracking down
the EC register that holds the radio switch state.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Henning Schild <henning@wh9.tu-dresden.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

The firmware knows how many hot keys it supports, so export this
information in a sysfs attribute.

And the driver knows which keys are always handled by the firmware in all
known ThinkPad models too, so export this information as well in a sysfs
attribute.  Unless you know which events need to be handled in a passive
way, do *not* enable hotkeys that are always handled by the firmware.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Revise ACPI HKEY functionality to better interface with the firmware, and
enable up to 32 regular hotkeys, instead of just 16 of them.  Ouch.

This takes care of most keys one used to have to do CMOS NVRAM polling on,
and should drop the need for tpb, thinkpad-keys, and other such 5Hz NVRAM
polling power vampires on most modern ThinkPads ;-)

And, just to add insult to injury, this was sort of working since forever
through the procfs interface, but nobody noticed or tried an echo
0xffffffff > /proc/acpi/ibm/hotkey and told me it would generate weird
events. ARGH!

Thanks to Richard Hughes for kicking off the work that ended up with this
discovery, and to Matthew Garret for calling my attention to the fact that
newer ThinkPads were indeed generating ACPI GPEs when such hot keys were
pressed.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Richard Hughes <hughsient@gmail.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Update the documentation with some extra data on the T43 thermal sensor
@0xc1, thanks to Alexey Fisher.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

The initial version of the thinkpad-acpi sysfs interface (not yet released
in any stable mainline kernel) made liberal use of named sysfs groups, in
order to get the attributes more organized.

This proved to be a really bad design decision.  Maybe if attribute groups
were as flexible as a real directory, and if binary attributes were not
second-class citizens, the idea of subdirs and named groups would not have
been so bad.

This patch makes all the thinkpad-acpi sysfs groups anonymous (thus
removing the subdirs), adds the former group names as a prefix (so that
hotkey/enable becomes hotkey_enable for example), and updates the
documentation.

These changes will make the thinkpad-acpi sysfs ABI a lot easier to
maintain.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add support to sysfs to the wan and bluetooth subdrivers.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

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

Improve fan control documentation and fix one mistake.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Len Brown considers that an active by default fan control interface in
laptops may be too close to giving users enough rope.  There is a good
chance he is quite correct on this, especially if someone decides to use
that interface in applets and users are not aware of its risks.

This patch adds a master switch to thinkpad-acpi that enables or disables
the entire fan-control feature as a module parameter: "fan_control".  It
defaults to disabled.  Set it to non-zero to enable fan control.

Also, the patch removes the expermiental status from fan control, since it
is stable enough to not be called experimental, and the master switch makes
it safe enough to do so.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Update the brightness sysfs interface (done through the backlight class) to
be in line with the rest of the thinkpad-acpi driver.

This renames the incorrect, un-obvious, and clash-prone name of "ibm" for
the backlight device to a much more fitting and descriptive
"thinkpad_screen".  This is something I wanted to do for quite a while...
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add sysfs attributes to send ThinkPad CMOS commands.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Export sysfs attributes to monitor and control the internal thinkpad fan
(some thinkpads have more than one fan, but thinkpad-acpi doesn't support
the second fan yet).  The sysfs interface follows the hwmon design guide
for fan devices.

Also, fix some stray "thermal" files in the fan procfs description that
have been there forever, and officially support "full-speed" as the name
for the PWM-disabled state of the fan controller to keep it in line with
the hwmon interface.  It is much better a name for that mode than the
unobvious "disengaged" anyway.  Change the procfs interface to also accept
full-speed as a fan level, but still report it as disengaged for backwards
compatibility.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Export thinkpad thermal sensors to sysfs, following the hwmon
specification for thermal monitoring sensors.

ThinkPad thermal monitoring is done by the EC.  Sensors can show up or
disappear at runtime when they are inside hotswappable hardware, such as
batteries.  Sensors that are not available return -ENXIO when accessed.

Up to 16 thermal sensors are supported on new firmware (but nobody has
reported a ThinkPad with more than 12 sensors so far), and 8 sensors are
supported on older firmware.  Thermal sensor mapping is model-specific.
Precision varies, it is 1 degree Celcius on new ThinkPads, but higher on
some older models.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add the sysfs attributes for the platform driver.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Register thinkpad-acpi platform driver and platform device for the device
model.  Also register the platform device with the hwmon class.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Improve the detection of ThinkPads, so as to reduce the chances of false
positives.

Since this could potentially add false negatives on the very old models,
add a module parameter to force the detection of a thinkpad.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add debug messages to the subdriver initialization and exit code.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a debug mode parameter and verbose debug mode Kconfig option.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Cleanup documentation, driver strings and other misc stuff, now that the
driver is named "thinkpad-acpi".
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Rename the ibm-acpi driver to thinkpad-acpi.  ThinkPads are not even made
by IBM anymore, so it is high time to rename the driver...

The name thinkpad-acpi was used sometime ago by a thinkpad-specific hotkey
driver by Erik Rigtorp, around the 2.6.8-2.6.10 time frame.  The driver
apparently never got merged into mainline (it did make some trips through
-mm).  ibm-acpi was merged soon after, making its debut in 2.6.10.

The reuse of the thinkpad-acpi name shouldn't be a problem as far as user
confusion goes, as Erik's thinkpad-acpi apparently didn't get widespread
use in the Linux ThinkPad community and most hits for thinkpad-acpi in
google point to ibm-acpi anyway.

Erik, if you read this, please consider the reuse of the thinkpad-acpi name
as a compliment to your effort to make ThinkPads more useful to all of us.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

Update documentation header, and relocate a hunk of text that was missplaced.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>

I shall protect the ibm-acpi city against the invasion of the barbarian
blanks!  To the unforgiving jaws of sed s/[[:blank:]]\+$// they go!
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NLen Brown <len.brown@intel.com>