Input: Revert "wacom - testing result shows get_report is unnecessary."

This reverts commit 1b2faaf7e219fc2905d75afcd4c815e5d39eda80.

The Intuos4 series presents a bug in which it hangs if it receives
a set feature command while switching to the enhanced mode.
This bug is triggered when plugging an Intuos 4 while having
a gnome user session up and running.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - assign phys field from struct wacom into input_dev

This field was not used for 9 years, it is time to assign it.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - create a separate input device for pads

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: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - split out the pad device for Intuos/Cintiq

MSC_SERIAL can be safely dropped for pad input devices.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - split out the pad device for Bamboos

We rely on the return code of wacom_bpt*() to do the input_sync().
wacom_wac_irq() then properly sync the input devices.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - split out the pad device for DTUS

MSC_SERIAL can be safely removed from the pad device.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - split out the pad device for Graphire G4 and MO

MSC_SERIAL can be safely removed from pad devices. If it is not
here, xf86-input-wacom correctly generates ones for its internal
use.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - split out the pad device for the wireless receiver

The Wireless Receiver should also behave in the same way than regular
USB devices.

To simplify the unregistering of the different devices,
wacom_unregister_inputs() is introduced.
For consistency, the function wacom_register_input() is renamed into
wacom_register_inputs().

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - include and use linux/hid.h

The current wacom code redefines constants that are already in linux/hid.h
This patch includes the official implementation and use it accross the code.

There is a conflict with HID_USAGE and others at the same level:
- in the wacom.ko implementation, those are the #define regarding the
  value of the field in the report descriptor
- in the hid.h, those are bitmask
So add HDESC_ in their current definition.

Also, the struct hid_descriptor slightly differs from the linux/hid.h
point of view, so mark it as custom for this driver.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - switch from an USB driver to a HID driver

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: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - use hid communication instead of plain usb

Wacom.ko was a plain USB driver for a HID device. The communications
from/to the devices can actually be replaced with the HID API.

At the USB level, the reports are exactly the same.

This will allow to use uhid virtual devices instead of true USB devices.
This step is necessary to implement regression tests.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - use HID core to actually fetch the report descriptor

HID core already retrieves the report descritor. There is no need
to ask ourself for one.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - compute the HID report size to get the actual packet size

This removes an USB dependency and is more accurate: the computed pktlen
is the actual maximum size of the reports forwarded by the device.

Given that the pktlen is correctly computed/validated, we can store it now
in the features struct instead of having a special handling in the rest of
the code.

Likewise, this information is not mandatory anymore in the description
of devices in wacom_wac.c. They will be removed in a separate patch.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - install LED/OLED sysfs files in the HID device instead of USB

Removes one more dependency over USB, but requires some changes in
the user space to find the sysfs files correctly.

This patch breaks the user space. However, the number of program
accessing the LEDs is quite limited and we can easily patch them
to handle the new HID behavior.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - register the input devices on top of the HID one

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: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - remove usb dependency for siblings devices

Wacom tablets can share different physical sensors on one physical device.
These are called siblings in the code. The current way of implementation
relies on the USB topology to be able to share data amongs those sensors.

We can replace the code to match a HID subsystem, without involving the USB
topology:
- the first probed sensor does not find any siblings in the list
  wacom_udev_list, so it creates its own wacom_hdev_data with its own
  struct hid_device
- the other sensor checks the current list of siblings in wacom_hdev_data,
  and if there is a match, it associates itself to the matched device.

To be sure that we are not associating different sensors from different
physical devices, we also check for the phys path of the hid device which
contains the USB topology.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - register power device at the HID level

Use the HID device as the parent for the power device when dealing with
a wireless receiver.
Removes one more usb dependency and does not break user space.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - use hid_info instead of plain dev_info

Removes one more need of usb and intf.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - use in-kernel HID parser

HID already parses the report descriptor, so use it instead of implementing
our own.  The special case for Bamboo PT 3rd gen is also removed and
handled in the same way Intuos 5 is treated, by hardcoding it in the
driver.  Last, the unit_exponent stored into the hid field already is
signed, so there is no need to handle a two's complement anymore.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Input: wacom - use hidinput_calc_abs_res instead of duplicating its code

This may infer a small difference with the previous implementation
due to the DIV_ROUND_CLOSEST() in the hid implementation.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <killertofu@gmail.com>
Tested-by: Jason Gerecke <killertofu@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>