The Intuos Pro seems to not like when we set the features right after
being powered up. Instead of waiting during probe, we can schedule the
switch mode and LED control in a deferred worker so that we don't have the
5 secs of delay from USB when the device is not accessible.

The USB timeout delays were really a pain because if you happen to unplug
the tablet while it is still waiting, you are just adding 5 second timeouts
to the USB stack. Which means that a new plug of the same tablet will also
gets delayed, and will also attempt to access the hardware while in
.probe(). So the tablet doesn't appear in the dmesg, the user unplug/replug
it to make it appearing... and so on so forth.

Really, this is for the best :)
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

It is unnecessary to return a value since nothing is expecting a
value from it.
Signed-off-by: NPing Cheng <ping.cheng@wacom.com>
Reviewed-By: NJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Instead of displaying a generic "tablet", now g-c-c shows a pretty
"Wacom Intuos Pro S (WL)".
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Looks like upowerd is ignoring this since October 2013, so there is
no need to keep this around in the kernel.
And as mentioned in 8aaa592 (linux: Ignore ACs coming from devices) in
the upower tree, "We already have enough information on the device
battery".
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The EKR switches the LED directly, and there is no point in having
userspace handling the switch it self when it's easy enough to do
in the kernel.

The other benefit is that now userspace does not need to have root access
to the LED but need only to read them with user privileges.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

There is a bug (?) in devm_led_classdev_register() in which its increments
the refcount of the parent. If the parent is an input device, that means
the ref count never reaches 0 when devm_input_device_release() gets called.
This means that the LEDs and all the devres resources attached to the
input device are not released.

Manually force the release of the group so that the leds are released once
we are done using them.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The now obsolete sysfs files for LEDs and EKRemote are kept for backward
compatibility.
Both the EKR (read-only) and the regular Cintiqs and Intuos are now
sharing the same led API.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Previously, all the remotes attached to the same receiver would share the
same power_supply. That's not good as the remotes will constantly change
the battery information according to their own state.

To have something generic enough, we introduce struct wacom_battery
which regroups all the information we need for a battery.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Thanks to devres, we can now afford to create more than one input node
without having to overload the remove/failure paths. Having one input
node per remote is something which should have been implemented from start
but the probability of having users with several remotes is quite low.
Anyway, still, better looking at the future and implement things properly.

Remote input nodes will be freed/unregistered magically as they are
created in the devres group &remote->remotes[index].

We need to open the hid node now that the remotes are dynamically
allocated.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

No functional changes, just a prep patch for the one after.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

If we want to have one input device per remote, it's better to have our
own struct wacom_remote which is dynamically allocated.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

wacom_remote_status_irq() sends information of addition/removal of EKR.
We want to allocate one input node per remote, so better having this
in a separate worker, not handled in the IRQ directly.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

We need to add an action to ensure wacom->led.groups is null when
wacom_led_control() gets called after the resources has been freed.

This also prevents to send a LED command when there is no support
from the device.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Use our own wacom_devm_sysfs_create_group() as there is currently no
generic one. It has been requested at least twice [1][2] but has been
always rejected.
However, in the Wacom case, for the wirelessly connected devices, we need
to be able to release the created sysfs files without removing the parent
kobject.

[1] https://patchwork.kernel.org/patch/7526551/
[2] https://lkml.org/lkml/2013/3/14/728Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

We currently have a complex clean_inputs() function while this can be
handled all by devres. Set a group that we can destroy in wireless_work().
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Looks like the battery hijacked the wireless worker. That's not fair so
use a work queue per task.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This device is pad (buttons) only, there is no stylus or touch. Up to
five remotes can pair with the device's associated USB dongle.
Signed-off-by: NAaron Skomra <aaron.skomra@wacom.com>
Reviewed-by: NJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This splits the 'wacom_setup_pentouch_input_capabilites' function into
pieces dedicated to doing setup for just the pen interface and just
the touch interface. This makes it easier to focus on the relevant
piece when making changes.

This patch introduces no functional changes.
Signed-off-by: NJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

It makes probe routine easy to follow.
Signed-off-by: NPing Cheng <pingc@wacom.com>
Reviewed-by: NJason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Change the ownership of power_supply structure from each driver
implementing the class to the power supply core.

The patch changes power_supply_register() function thus all drivers
implementing power supply class are adjusted.

Each driver provides the implementation of power supply. However it
should not be the owner of power supply class instance because it is
exposed by core to other subsystems with power_supply_get_by_name().
These other subsystems have no knowledge when the driver will unregister
the power supply. This leads to several issues when driver is unbound -
mostly because user of power supply accesses freed memory.

Instead let the core own the instance of struct 'power_supply'.  Other
users of this power supply will still access valid memory because it
will be freed when device reference count reaches 0. Currently this
means "it will leak" but power_supply_put() call in next patches will
solve it.

This solves invalid memory references in following race condition
scenario:

Thread 1: charger manager
Thread 2: power supply driver, used by charger manager

THREAD 1 (charger manager)         THREAD 2 (power supply driver)
==========================         ==============================
psy = power_supply_get_by_name()
                                   Driver unbind, .remove
                                     power_supply_unregister()
                                     Device fully removed
psy->get_property()

The 'get_property' call is executed in invalid context because the driver was
unbound and struct 'power_supply' memory was freed.

This could be observed easily with charger manager driver (here compiled
with max17040 fuel gauge):

$ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
$ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
[   55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[   55.732584] pgd = d98d4000
[   55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
[   55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[   55.746210] Modules linked in:
[   55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G        W       3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
[   55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
[   55.771647] PC is at 0x0
[   55.774182] LR is at charger_get_property+0x2f4/0x36c
[   55.779201] pc : [<00000000>]    lr : [<c034b0b4>]    psr: 60000013
[   55.779201] sp : daf55e90  ip : 00000003  fp : 00000000
[   55.790657] r10: 00000000  r9 : c06e2878  r8 : d9b26c68
[   55.795865] r7 : dad81610  r6 : daec7410  r5 : daf55ebc  r4 : 00000000
[   55.802367] r3 : 00000000  r2 : daf55ebc  r1 : 0000002a  r0 : d9b26c68
[   55.808879] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   55.815994] Control: 10c5387d  Table: 598d406a  DAC: 00000015
[   55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
[   55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
[   55.831795] 5e80:                                     60000013 c01459c4 0000002a c06f8ef8
[   55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
[   55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
[   55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
[   55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
[   55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
[   55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
[   55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
[   55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
[   55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
[   55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
[   55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
[   55.929744] [<c034b0b4>] (charger_get_property) from [<c0346864>] (power_supply_show_property+0x48/0x20c)
[   55.939286] [<c0346864>] (power_supply_show_property) from [<c027f25c>] (dev_attr_show+0x1c/0x48)
[   55.948130] [<c027f25c>] (dev_attr_show) from [<c0146218>] (sysfs_kf_seq_show+0x84/0x104)
[   55.956298] [<c0146218>] (sysfs_kf_seq_show) from [<c0144c78>] (kernfs_seq_show+0x24/0x28)
[   55.964536] [<c0144c78>] (kernfs_seq_show) from [<c0107f90>] (seq_read+0x1b0/0x484)
[   55.972172] [<c0107f90>] (seq_read) from [<c00e53dc>] (__vfs_read+0x18/0x4c)
[   55.979188] [<c00e53dc>] (__vfs_read) from [<c00e548c>] (vfs_read+0x7c/0x100)
[   55.986304] [<c00e548c>] (vfs_read) from [<c00e5550>] (SyS_read+0x40/0x8c)
[   55.993164] [<c00e5550>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[   56.000626] Code: bad PC value
[   56.011652] ---[ end trace 7b64343fbdae8ef1 ]---
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

[for the nvec part]
Reviewed-by: NMarc Dietrich <marvin24@gmx.de>

[for compal-laptop.c]
Acked-by: NDarren Hart <dvhart@linux.intel.com>

[for the mfd part]
Acked-by: NLee Jones <lee.jones@linaro.org>

[for the hid part]
Acked-by: NJiri Kosina <jkosina@suse.cz>

[for the acpi part]
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Tablets like the Intuos, Intuos Pro, and Bamboo have a connector for an
optional wireless module that can be connected on the fly. The presence
(or absence) of this module is indicated in a status report recieved
from the tablet. This patch adds a workqueue function that will create
or destroy a power_supply object at runtime to match the current state
of the WACOM_QUIRK_BATTERY flag.
Signed-off-by: NJason Gerecke <killertofu@gmail.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Has the 'wacom_notify_battery' function take on the job of detecting if
updating the power supply is necessary to remove multiple
nearly-identical 'if' blocks.
Signed-off-by: NJason Gerecke <killertofu@gmail.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Bamboo models do not support HID_DG_CONTACTMAX. Plus, Bamboo pen-only
has touch descriptor. This leads to some complications in the code.

This patch also fixes duplicated PAD interfeaces for Intuos Pen
models.
Signed-off-by: NPing Cheng <pingc@wacom.com>
Reviewed-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

ISDv4 and v5 are plain HID devices. We can directly implement a generic
HID parsing/handling and remove the need to manually add those PID in
the list of supported devices.

This patch implements the pen support only. The finger part will come in
a later patch.

To be properly notified of an .event() and a .report(), we need to force
hid-core to go through the HID parsing. By default, wacom.ko binds only
hidraw, so the hid parsing is not done by hid-core. When a true HID device
is there, we add the flag HID_CLAIMED_DRIVER to hid->claimed which will
force hid-core to parse the incoming reports.
(Note that this can be easily backported by directly setting the .claimed
flag to HID_CLAIMED_DRIVER even if hid-core does not support
HID_CONNECT_DRIVER)
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NJason Gerecke <killertofu@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Putting the various MODULE_* makes them appear several times in modinfo
because wacom.h is used both in wacom_sys.c and wacom_wac.h.
Having the macros near the module declaration makes them appear only once.

Add also MODULE_VERSION(DRIVER_VERSION) to export the current version
number.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Reviewed-by: NPing Cheng <pingc@wacom.com>
Tested-by: NPrzemo Firszt <przemo@firszt.eu>
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

This is used by HID Bluetooth devices but also add some more information
to the USB Wireless Receiver.
We are just porting the bits from hid-wacom.c to the common driver here.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPrzemo Firszt <przemo@firszt.eu>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

- Reports the current status of the battery (discharging, charging, full).
- Also notify the upower daemon when there is a change in the battery
  value.
- keep the battery value as a percentage, not the raw value
- add WACOM_QUIRK_BATTERY to easily add a battery to a device (required
  for Bluetooth devices)
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPrzemo Firszt <przemo@firszt.eu>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

This solves a bug with the wireless receiver:
- at plug, the wireless receiver does not know which Wacom device it is
  connected to, so it does not actually creates all the LEDs
- when the tablet connects, wacom->wacom_wac.features.type is set to the
  proper device so that wacom_wac can understand the packets
- when the receiver is unplugged, it detects that a LED should have been
  created (based on wacom->wacom_wac.features.type) and tries to remove
  it: crash when removing the sysfs group.

Side effect, we can now safely call several times wacom_destroy_leds().
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

wacom.ko is now a full HID driver, we have to move it into the proper
subdirectory: drivers/hid.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Matches the current behavior of the HID subsystem and removes one more
dependency over USB.

The current user space clients which relies on this to fetch the
LEDs path need an update. However, we already break them in the
kernel v3.11 for the Bluetooth Wacom devices. They are going to be fixed
soon.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: NJason Gerecke <killertofu@gmail.com>
Tested-by: NJason Gerecke <killertofu@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

All USB Wacom tablets are actually HID devices.
For historical reasons, they are handled as plain USB devices.
The current code makes more and more reference to the HID subsystem
like implementing its own HID report descriptor parser to handle new
devices.

From the user point of view, we can transparently switch from this state
to a driver handled in the HID subsystem and clean up a lot of USB specific
code in the wacom.ko driver.

The other benefit once the USB dependecies have been removed is that we can
use a tool like uhid to make regression tests and allow further cleanup or
new implementations without risking breaking current behaviors.

To match the current handling of devices in wacom_wac.c, we rely on the
hid_type set by usbhid. usbhid sets the hid_type to HID_TYPE_USBMOUSE when
it sees a USB boot mouse protocol declared and HID_TYPE_USBNONE when the
device is plain HID. There is thus a one to one matching between the list
of supported devices before and after the switch from USB to HID.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: NJason Gerecke <killertofu@gmail.com>
Tested-by: NJason Gerecke <killertofu@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Currently, the pad events are sent through the stylus input device
for the Intuos/Cintiqs, and through the touch input device for the
Bamboos.

To differentiate the buttons pressed on the pad from the ones pressed
on the stylus, the Intuos/Cintiq uses MISC_SERIAL and ABS_MISC. This
lead to a multiplexing of the events into one device, which are then
splitted out in xf86-input-wacom. Bamboos are not using MISC events
because the pad is attached to the touch interface, and only BTN_TOUCH
is used for the finger (and DOUBLE_TAP, etc...). However, the user space
driver still splits out the pad from the touch interface in the same
way it does for the pro line devices.

The other problem we can see with this fact is that some of the Intuos
and Cintiq have a wheel, and the effective range of the reported values
is [0..71]. Unfortunately, the airbrush stylus also sends wheel events
(there is a small wheel on it), but in the range [0..1023]. From the user
space point of view it is kind of difficult to understand that because
the wheel on the pad are quite common, while the airbrush tool is not.

A solution to fix all of these problems is to split out the pad device
from the stylus/touch. This decision makes more sense because the pad is
not linked to the absolute position of the finger or pen, and usually, the
events from the pad are filtered out by the compositor, which then convert
them into actions or keyboard shortcuts.

For backward compatibility with current xf86-input-wacom, the pad devices
still present the ABS_X, ABS_Y and ABS_MISC events, but they can be
completely ignored in the new implementation.
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: NPing Cheng <pingc@wacom.com>
Reviewed-by: NJason Gerecke <killertofu@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Main part of patch is adding support for a new Wacom MT touch
packet and labels these devices using MTSCREEN type.

Other items of interest:

Delete some duplicate code in HID parsing for Y info since
its already done in X path.

In wacom_query_tablet_data(), only invoke the set report
that requests tablets to send Wacom Touch packets for
Finger interfaces.  Mostly, this is to make code intent clear.
Tested-by: NJason Gerecke <killertofu@gmail.com>
Signed-off-by: NChris Bagwell <chris@cnpbagwell.com>
Signed-off-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Signed-off-by: NChris Bagwell <chris@cnpbagwell.com>
Tested-by: NJason Gerecke <killertofu@gmail.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

When a tablet connect or disconnect is detected, schedule
work queue to register or unregister related input devices.

When a wireless tablet connects, it reports same USB PID
used if tablet is connected with USB cable. Use this to
update features values, set input capabilities, and then
register device.  From there, the Pen and Touch interfaces
will reuse the existing tablet's IRQ routines.

Its possible that 1 receiver is shared with 2 tablets with
different PID (small and medium Bamboo for example) so the
input is unregister at disconnect to better support this case.
Signed-off-by: NChris Bagwell <chris@cnpbagwell.com>
Tested-by: NJason Gerecke <killertofu@gmail.com>
Acked-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Cintiq 21ux2 has two sets of four LEDs on right and left side of
the tablet, respectively.
Reviewed-by: NEduard Hasenleithner <eduard@hasenleithner.at>
Tested-by: NEduard Hasenleithner <eduard@hasenleithner.at>
Signed-off-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The LED also indicates the status of the tablet. Don't turn it off.
Reviewed-by: NEduard Hasenleithner <eduard@hasenleithner.at>
Tested-by: NEduard Hasenleithner <eduard@hasenleithner.at>
Signed-off-by: NPing Cheng <pingc@wacom.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

This commit enables control of the LEDs and OLED displays found on the
Wacom Intuos4 M, L, and XL. For this purpose, a new "wacom_led" attribute
group is added to the sysfs entry of the USB device.

This "wacom_led" group only shows up when the correct device (M, L, or XL)
is detected. The attributes are described in
 Documentation/ABI/testing/sysfs-wacom
Signed-off-by: NEduard Hasenleithner <eduard@hasenleithner.at>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>