The Wii Remote has several extension ports. The first port (EXT) provides
hotplug events whenever an extension is plugged. The second port (MP)
does not provide hotplug events by default. Instead, we have to map MP
into EXT to get events for it.

This patch introduces hotplug support for extensions. It is fairly
complicated to get this right because the Wii Remote sends a lot of
noise-hotplug events while activating extension ports. We need to filter
the events and only handle the events that are real hotplug events.

Mapping MP into EXT is easy. But if we want both, MP _and_ EXT at the same
time, we need to map MP into EXT and enable a passthrough-mode. This will
then send real EXT events through the mapped MP interleaved with real MP
events. But once MP is mapped, we no longer have access to the real EXT
registers so we need to perform setup _before_ mapping MP. Furthermore, we
no longer can read EXT IDs so we cannot verify if EXT is still the same
extension that we expect it to be.
We deal with this by unmapping MP whenever we got into a situation where
EXT might have changed. We then re-read EXT and MP and remap everything.

The real Wii Console takes a fairly easy approach: It simply reconnects to
the device on hotplug events that it didn't expect. So if a program wants
MP events, but MP is disconnected, it fails and reconnects so it can wait
for MP hotplug events again.
This simplifies hotplugging a lot because we just react on PLUG events and
ignore UNPLUG events.
The more sophisticated Wii applications avoid reconnection (well, they
still reconnect during many weird events, but at least not during UNPLUG)
but they start polling the device. This allows them to disable the device,
poll for the extension ports to settle and then initialize them again.
Unfortunately, this approach fails whenever an extension is replugged
while it is initialized. We would loose UNPLUG events and polling the
device later will give unreliable results because the extension port might
be in some weird state, even though it's actually unplugged.

Our approach is a real HOTPLUG approch. We keep track of the EXT and
mapped MP hotplug events whenever they occur. We then re-evaluate the
device state and initialize any possible new extension or deinitialize any
gone extension. Only during initialization, we set an extension port
ACTIVE. However, during an unplug event we mark them as INACTIVE. This
guarantess that a fast UNPLUG -> PLUG event sequence doesn't keep them
marked as PLUGGED+ACTIVE but only PLUGGED.
To deal with annoying noise-hotplug events during extension mapping, we
simply rescan the device before performing any mapping. This allows us to
ignore all the noise events as long as the device is in the correct state.

Long story short: EXT and MP registers are sparsely known and we need to
jump through hoops to get reliable HOTPLUG working. But while Nintendo
needs *FOUR* Bluetooth reconnections for the shortest imaginable
boot->menu->game->menu->shutdown sequence, we now need *ZERO*.

As always, 3rd party devices tend to break whenever we behave differently
than the original Wii. So there are also devices which _expect_ a
disconnect after UNPLUG. Obviously, these devices won't benefit from this
patch. But all official devices were tested extensively and work great
during any hotplug sequence. Yay!
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

IR is the last piece that still is handled natively. This patch converts
it into a sub-device module like all other sub-devices. It mainly moves
code and doesn't change semantics.

We also implicitly sync IR data on ir_to_input3 now so the explicit
input_sync() calls are no longer needed.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Accelerometer data is very similar to KEYS handling. Therefore, convert
all ACCEL related handling into a sub-device module similar to KEYS.

This doesn't change any semantics but only moves code over to
wiimote-modules.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Each of the 4 LEDs may be supported individually by devices. Therefore,
we need one module for each device. To avoid code-duplication, we simply
pass the LED ID as "arg" argument to the module loading code.

This just moves the code over to wiimote-module. The semantics stay the
same as before.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This introduces a new sub-device module for the BATTERY handlers. It
moves the whole power_supply battery handling over to wiimote-modules.

This doesn't change any semantics or ABI but only converts the battery
handling into a sub-device module.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This introduces the first sub-device modules by converting the KEYS and
RUMBLE sub-devices into wiimote modules. Both must be converted at once
because they depend on the built-in shared input device.

This mostly moves code from wiimote-core to wiimote-modules and doesn't
change any semantics or ABI.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

To avoid loading all sub-device drivers for every Wii Remote, even though
the required hardware might not be available, we introduce a module layer.

The module layer specifies which sub-devices are available on each
device-type. After device detection, we only load the modules for the
detected device. If module loading fails, we unload everything and mark
the device as WIIMOTE_DEV_UNKNOWN. As long as a device is marked as
"unknown", no sub-devices will be used and the device is considered
unsupported.

All the different sub-devices, including KEYS, RUMBLE, BATTERY, LEDS,
ACCELEROMETER, IR and more will be ported in follow-up patches to the new
module layer.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Our output queue is asynchronous but synchronous reports may wait for a
response to their request. Therefore, wake them up unconditionally if an
output report couldn't be sent. But keep the report ID intact so we don't
incorrectly assume our request succeeded.

Note that the underlying connection is required to be reliable and does
retransmission itself. So it is safe to assume that if the transmission
fails, the device is in inconsistent state. Hence, we abort every request
if any output report fails. No need to verify which report failed.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Battery reports are sent along every status report of the Wii Remote.
So chances are pretty high that we have an up-to-date battery
cache at any time. Therefore, initialize the battery-cache to 100% and
then return battery values from the cache if the query fails.

This works around a power_supply limitation in that it requires us to be
able to query the device during power_supply registration and
removal. Otherwise, "add" or "remove" udev events are not sent. If
we answer these requests from our cache instead, we avoid dropping these
events and no longer cause warnings printed.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Nintendo produced many different devices that are internally based on the
Wii Remote protocol but provide different peripherals. To support these
devices, we need to schedule a device detection during initialization.

Device detection includes requesting a status report, reading extension
information and then evaluating which device we may be dealing with.

We currently detect gen1 and gen2 Wii Remote devices. All other devices
are marked as generic devices. More detections will be added later.

In followup patches we will be using these device IDs to control which
peripherals to initialize. For instance if a device is known to have no IR
camera, there is no need to provide the IR input device nor trying to
access IR registers. In fact, there are 3rd party devices that break if we
try things like this (hurray!).

The init_worker will be scheduled whenever we get hotplug events. This
isn't implemented, yet and will be added later. However, we need to make
sure that this worker can be called multiple times.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

We need constant I/O to keep the state up-to-date and not miss any
packets. Hence, call hid_hw_open() during setup and hid_hw_close() during
destruction.

These are no-ops for Bluetooth HIDP, but lets be safe.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The output queue is independent of the other wiimote modules and can run
on its own. Therefore, move its members into a separate struct so we don't
run into name collisions with other modules.

This is only a syntactic change that renames all queue members to queue.*.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The hid-wiimote driver supports more than the Wii Remote. Nintendo
produced many devices based on the Wii Remote, which have extension
devices built-in. It is not clear to many users, that these devices have
anything in common with the Wii Remote, so fix the driver description.

This also updates the copyright information for the coming hotplugging
rework.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

It turns out the Wii accepts any status reports from clients reduced to
"BB BB" key data only, as long as the report actually includes key data at
the first two bytes.

The official devices don't send these reduced reports, but of course, 3rd
party devices make great use of this feature.

Hence, add parsers for these reduced reports for every matching report.
Also change the logic how we find handlers. There is no reason to call
multiple handlers on a single report, but instead find the best handler
and call it only once.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This adds the 2nd generation Wii Remote IDs. They have a different
Bluetooth chipset (CSR instead of Broadcom) and are more restrictive in
what they accept as input. Hence, you need up-to-date BlueZ and
Bluetooth HIDP modules to use these devices.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Battery device names must be unique, otherwise registration fails if
multiple Wii Remotes are connected.

This breaks the sysfs API, but there is no known application that uses the
Wii Remote battery that I know of so we should go ahead and apply this.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Use the new module_hid_driver macro in all HID drivers that have
a simple register/unregister init/exit.

This also converts the hid drivers that test for a failure of
hid_register_driver() and report the failure. Using module_hid_driver
in those drivers removes the failure message.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

We incorrectly parse incoming IR data. The extra byte contains the upper
bits and not the lower bits of the x/y coordinates. User-space expects
absolute position data from us so this patch does not break existing
applications. On the contrary, it extends the virtual view and fixes
garbage reports for margin areas of the virtual screen.

Cc: stable@kernel.org
Reported-by: NPeter Bukovsky <bukovsky.peter@gmail.com>
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Analogically to d7cb3dbd ("HID: wacom: Fix invalid power_supply_powers
calls"), fix also the same occurence in wiimote driver.

Reported-by: przemo@firszt.eu
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Newer bluetooth stack supports the NO_INIT_REPORTS quirk. The wiimote does not
support report initialization so enable it by default.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The version number is not needed at all for in-tree drivers. Upstream git is
used to track module versions.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Keep track of current drm and add new debugfs file which reads or writes the
current DRM.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The wiimote provides direct access to parts of its eeprom. This implements read
support for small chunks of the eeprom. This isn't very fast but prevents the
reader from blocking the wiimote stream for too long.

Write support is not yet supported as the wiimote breaks if we overwrite its
memory. Use hidraw to reverse-engineer the eeprom before implementing write
support here.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add initializer and deinitializer for debugfs support. This will later allow raw
eeprom access and direct DRM modifications to debug wiimote behaviour and
further protocol reverse-engineerings.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

All supported extensions report data as 6 byte block. All DRMs with extension
data provide at least 6 extension bytes. Hence a generic handler for all
extension bytes is sufficient and can be called on all DRMs.

The handler distinguishes the input and passes it to the right handler. Motion+
passes data interleaved so we can have Motion+ and a regular extension enabled
simultaneously.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The wiimote supports several extensions. This adds a separate source file which
handles all extensions and can be disabled at compile-time.

The driver reacts on "plug"-events on the extension port and starts a worker
which initializes or deinitializes the extensions.

Currently, the initialization logic is not fully understood and we can only
detect and enable all extensions when all extensions are deactivated. Therefore,
we need to disable all extensions, then detect and activate them again to react
on "plug"-events.
However, deactivating extensions will generate a new "plug"-event and we will
never leave that loop. Hence, we only support extensions if they are plugged
before the wiimote is connected (or before the ext-input device is opened). In
the future we may support full extension hotplug support, but
reverse-engineering this may take a while.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add helper functions similar to the write-mem helpers but for reading wiimote
memory and eeprom.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Wiimote extension and sound support need access to several symbols so move them
into a new header.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Extension and sound support for the wiimote are quite complex and will be
implemented in separate source files. Hence rename the current driver to "-core"
suffix so multiple files can be linked into this module.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add entry to MAINTAINERS and also bump version level as the core driver is
feature complete now.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This registers a power_supply device for every remote to retrieve the current
battery charge level. Since this information is not sent by the wiimote
continously, we need to explicitely request it.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The wiimote does not send status reports continuously so this adds a helper
function to request a status report and parses the battery charge level.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Initialize the IR cam if the related input device is opened by userspace. Stop
IR cam again if userspace is no longer interested in its data events.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The wiimote IR cam needs a fairly complex initialization sequence. This adds a
helper function that performs IR initialization synchronously.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add helpers to synchronously write registers of the wiimote. This is heavily
used by initialization functions for wiimote peripherals.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

To initialize wiimote peripherals, the stream to the wiimote must be held
exclusively by the initializer, otherwise the initialization will fail. Many
initializations require multiple memory requests to be sent synchronously so we
need a way to lock the stream and release it when we are done.

This adds several helper functions which allow to lock the stream, then send
requests, wait for the answers and release the stream again.

When holding the lock, the function may sleep and interrupted by signals.
Also it returns after a short timeout so userspace shouldn't notice long
delays.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The wiimote allows direct access to its memory mapped registers and
internal eeprom. This adds support to access this memory and handle
memory events.

There are two macros which wrap up the memory access functions to avoid
accidentally overwriting sensitive eeprom data because a boolean value
was wrongly set.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

If an extension is connected the wiimote may report data though DRMs that
contain extension data. This adds handlers for these DRMs but discards extension
data since we do not support it, yet.
It prints a warning to kernel log if an unhandled report is catched. Since we
handle all requests now, this should never happen, though.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Parse IR data and report it to IR input-device. IR data is sent in 3 different
formats, but we only support the basic format as there is no way to send the
additional information to userspace.
All three formats are compatible with the basic IR data format so we need only
one parser.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The IR cam of the wiimote reports 4 trackable lights as absolute values. Since
we can turn the IR cam on and off, we register a separate input device so we can
react on open/close callbacks to save wiimote battery power when IR cam is not
needed.

The cam can be in four states: off, basic, extended and full
The DRM chooser automatically selects a proper DRM that includes all required IR
data so no information is lost.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>