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: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

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

No Functional changes, just some reordering.
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>

pktlen is now overwritten by the driver directly by reading the hid
report descriptor. There is no need to declare it statically.
We also move down the position of the field in the struct so that
we can keep the current declaration of Wacom devices.
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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

This reverts commit 1b2faaf7.

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>

Pull more IIO driver fixes from Greg KH:
 "Here are two IIO driver fixes for 3.16-rc6 that resolve some reported
  issues"

* tag 'staging-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  iio: mma8452: Use correct acceleration units.
  iio:core: Handle error when mask type is not separate

Pull USB fixes from Greg KH:
 "Here are two USB patches that resolve some reported issues, one with
  an odd HUB, and one in the chipidea driver"

* tag 'usb-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: Check if port status is equal to RxDetect
  usb: chipidea: udc: Disable auto ZLP generation on ep0

Merge tag 'driver-core-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "Here is a single driver core fix that reverts an older patch that has
  been causing a number of reported problems with the platform devices.

  This revert has been in linux-next for a while with no reported issues"

* tag 'driver-core-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  platform_get_irq: Revert to platform_get_resource if of_irq_get fails

Pull char/misc fix from Greg KH:
 "Here's a single hyper-v driver fix for a reported issue"

* tag 'char-misc-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Drivers: hv: hv_fcopy: fix a race condition for SMP guest

Pull intel drm fixes from Dave Airlie:
 "Intel fixes came in late, but since I debugged one of them I'll send
  them on,

  Two reverts, a quirk and one warn regression"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  Revert "drm/i915: reverse dp link param selection, prefer fast over wide again"
  drm/i915: Track the primary plane correctly when reassigning planes
  drm/i915: Ignore VBT backlight presence check on HP Chromebook 14
  Revert "drm/i915: Don't set the 8to6 dither flag when not scaling"

Pull UML fixes from Richard Weinberger:
 "Four fixes, all discovered by Trinity"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: segv: Save regs only in case of a kernel mode fault
  um: Fix hung task in fix_range_common()
  um: Ensure that a stub page cannot get unmapped
  Revert "um: Fix wait_stub_done() error handling"

Pull btrfs fixes from Chris Mason:
 "We have two more fixes in my for-linus branch.

  I was hoping to also include a fix for a btrfs deadlock with
  compression enabled, but we're still nailing that one down"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: test for valid bdev before kobj removal in btrfs_rm_device
  Btrfs: fix abnormal long waiting in fsync

Pull NFS client fixes from Trond Myklebust:
 "Apologies for the relative lateness of this pull request, however the
  commits fix some issues with the NFS read/write code updates in
  3.16-rc1 that can cause serious Oopsing when using small r/wsize.  The
  delay was mainly due to extra testing to make sure that the fixes
  behave correctly.

  Highlights include;
   - Stable fix for an NFSv3 posix ACL regression
   - Multiple fixes for regressions to the NFS generic read/write code:
     - Fix page splitting bugs that come into play when a small
       rsize/wsize read/write needs to be sent again (due to error
       conditions or page redirty)
     - Fix nfs_wb_page_cancel, which is called by the "invalidatepage"
       method
   - Fix 2 compile warnings about unused variables
   - Fix a performance issue affecting unstable writes"

* tag 'nfs-for-3.16-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Don't reset pg_moreio in __nfs_pageio_add_request
  NFS: Remove 2 unused variables
  nfs: handle multiple reqs in nfs_wb_page_cancel
  nfs: handle multiple reqs in nfs_page_async_flush
  nfs: change find_request to find_head_request
  nfs: nfs_page should take a ref on the head req
  nfs: mark nfs_page reqs with flag for extra ref
  nfs: only show Posix ACLs in listxattr if actually present

...otherwise me lose user mode regs and the resulting
stack trace is useless.
Signed-off-by: Richard Weinberger <richard@nod.at>

If do_ops() fails we have to release current->mm->mmap_sem
otherwise the failing task will never terminate.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

Trinity discovered an execution path such that a task
can unmap his stub page.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

This reverts commit 0974a9ca.
The real for for that issue is to release current->mm->mmap_sem in
fix_range_common().
Signed-off-by: Richard Weinberger <richard@nod.at>

commit 99994cde btrfs: dev delete should remove sysfs entry
added a btrfs_kobj_rm_device, which dereferences device->bdev...
right after we check whether device->bdev might be NULL.

I don't honestly know if it's possible to have a NULL device->bdev
here, but assuming that it is (given the test), we need to move
the kobject removal to be under that test.

(Coverity spotted this)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>

xfstests generic/127 detected this problem.

With commit 7fc34a62, now fsync will only flush
data within the passed range.  This is the cause of the above problem,
-- btrfs's fsync has a stage called 'sync log' which will wait for all the
ordered extents it've recorded to finish.

In xfstests/generic/127, with mixed operations such as truncate, fallocate,
punch hole, and mapwrite, we get some pre-allocated extents, and mapwrite will
mmap, and then msync.  And I find that msync will wait for quite a long time
(about 20s in my case), thanks to ftrace, it turns out that the previous
fallocate calls 'btrfs_wait_ordered_range()' to flush dirty pages, but as the
range of dirty pages may be larger than 'btrfs_wait_ordered_range()' wants,
there can be some ordered extents created but not getting corresponding pages
flushed, then they're left in memory until we fsync which runs into the
stage 'sync log', and fsync will just wait for the system writeback thread
to flush those pages and get ordered extents finished, so the latency is
inevitable.

This adds a flush similar to btrfs_start_ordered_extent() in
btrfs_wait_logged_extents() to fix that.
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>