linux-toradex.git/include/linux/input.h, branch v6.4-rc1

Input: add input_copy_abs() function

2022-03-01T07:26:27+00:00

Add a new helper function to copy absinfo from one input_dev to
another input_dev.

This is useful to e.g. setup a pen/stylus input-device for combined
touchscreen/pen hardware where the pen uses the same coordinates as
the touchscreen.

Suggested-by: Dmitry Torokhov 
Signed-off-by: Hans de Goede 
Link: https://lore.kernel.org/r/20220131143539.109142-2-hdegoede@redhat.com
Signed-off-by: Dmitry Torokhov

Input: Add "inhibited" property

2020-12-03T06:10:35+00:00

Userspace might want to implement a policy to temporarily disregard input
from certain devices, including not treating them as wakeup sources.

An example use case is a laptop, whose keyboard can be folded under the
screen to create tablet-like experience. The user then must hold the laptop
in such a way that it is difficult to avoid pressing the keyboard keys. It
is therefore desirable to temporarily disregard input from the keyboard,
until it is folded back. This obviously is a policy which should be kept
out of the kernel, but the kernel must provide suitable means to implement
such a policy.

This patch adds a sysfs interface for exactly this purpose.

To implement the said interface it adds an "inhibited" property to struct
input_dev, and effectively creates four states a device can be in: closed
uninhibited, closed inhibited, open uninhibited, open inhibited. It also
defers calling driver's ->open() and ->close() to until they are actually
needed, e.g. it makes no sense to prepare the underlying device for
generating events (->open()) if the device is inhibited.

              uninhibit
closed      <------------ closed
uninhibited ------------> inhibited
      | ^     inhibit        | ^
 1st  | |               1st  | |
 open | |               open | |
      | |                    | |
      | | last               | | last
      | | close              | | close
      v |     uninhibit      v |
open        <------------ open
uninhibited ------------> inhibited

The top inhibit/uninhibit transition happens when users == 0.
The bottom inhibit/uninhibit transition happens when users > 0.
The left open/close transition happens when !inhibited.
The right open/close transition happens when inhibited.
Due to all transitions being serialized with dev->mutex, it is impossible
to have "diagonal" transitions between closed uninhibited and open
inhibited or between open uninhibited and closed inhibited.

No new callbacks are added to drivers, because their open() and close()
serve exactly the purpose to tell the driver to start/stop providing
events to the input core. Consequently, open() and close() - if provided
- are called in both inhibit and uninhibit paths.

Signed-off-by: Patrik Fimml 
Co-developed-by: Andrzej Pietrasiewicz 
Signed-off-by: Andrzej Pietrasiewicz 
Link: https://lore.kernel.org/r/20200608112211.12125-8-andrzej.p@collabora.com
Signed-off-by: Dmitry Torokhov

Input: add input_device_enabled()

2020-12-03T06:10:31+00:00

A helper function for drivers to decide if the device is used or not.
A lockdep check is introduced as inspecting ->users should be done under
input device's mutex.

Signed-off-by: Andrzej Pietrasiewicz 
Link: https://lore.kernel.org/r/20200608112211.12125-2-andrzej.p@collabora.com
Signed-off-by: Dmitry Torokhov

Input: add input_get_poll_interval()

2019-10-04T19:31:46+00:00

Some drivers need to be able to know the current polling interval for
devices working in polling mode, let's allow them fetching it.

Acked-By: Benjamin Tissoires 
Tested-by: Michal Vokáč 
Signed-off-by: Dmitry Torokhov

Input: add support for polling to input devices

2019-08-20T19:04:07+00:00

Separating "normal" and "polled" input devices was a mistake, as often we
want to allow the very same device work on both interrupt-driven and
polled mode, depending on the board on which the device is used.

This introduces new APIs:

- input_setup_polling
- input_set_poll_interval
- input_set_min_poll_interval
- input_set_max_poll_interval

These new APIs allow switching an input device into polled mode with sysfs
attributes matching drivers using input_polled_dev APIs that will be
eventually removed.

Tested-by: Michal Vokáč 
Acked-by: Benjamin Tissoires 
Signed-off-by: Dmitry Torokhov

Input: allow drivers specify timestamp for input events

2019-07-25T08:12:20+00:00

Currently, evdev stamps events with timestamps acquired in evdev_events()
However, this timestamping may not be accurate in terms of measuring
when the actual event happened.

Let's allow individual drivers specify timestamp in order to provide a more
accurate sense of time for the event. It is expected that drivers will set the
timestamp in their hard interrupt routine.

Signed-off-by: Atif Niyaz 
Signed-off-by: Dmitry Torokhov

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Enrico Weigelt 
Reviewed-by: Kate Stewart 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman

Input: allow matching device IDs on property bits

2017-10-19T23:54:49+00:00

Let's allow matching input devices on their property bits, both in-kernel
and when generating module aliases.

Tested-by: Roderick Colenbrander 
Signed-off-by: Dmitry Torokhov

Input: factor out and export input_device_id matching code

2017-10-19T23:53:34+00:00

Factor out and export input_match_device_id() so that modules may use it.
It will be needed by joydev to blacklist accelerometers in composite
devices.

Tested-by: Roderick Colenbrander 
Signed-off-by: Dmitry Torokhov

Input: uinput - avoid FF flush when destroying device

2017-09-21T23:31:22+00:00

Normally, when input device supporting force feedback effects is being
destroyed, we try to "flush" currently playing effects, so that the
physical device does not continue vibrating (or executing other effects).
Unfortunately this does not work well for uinput as flushing of the effects
deadlocks with the destroy action:

- if device is being destroyed because the file descriptor is being closed,
  then there is noone to even service FF requests;

- if device is being destroyed because userspace sent UI_DEV_DESTROY,
  while theoretically it could be possible to service FF requests,
  userspace is unlikely to do so (they'd need to make sure FF handling
  happens on a separate thread) even if kernel solves the issue with FF
  ioctls deadlocking with UI_DEV_DESTROY ioctl on udev->mutex.

To avoid lockups like the one below, let's install a custom input device
flush handler, and avoid trying to flush force feedback effects when we
destroying the device, and instead rely on uinput to shut off the device
properly.

NMI watchdog: Watchdog detected hard LOCKUP on cpu 3
...
 <>  [] _raw_spin_lock_irqsave+0x37/0x40
 [] complete+0x1d/0x50
 [] uinput_request_done+0x3c/0x40 [uinput]
 [] uinput_request_submit.part.7+0x47/0xb0 [uinput]
 [] uinput_dev_erase_effect+0x5b/0x76 [uinput]
 [] erase_effect+0xad/0xf0
 [] flush_effects+0x4d/0x90
 [] input_flush_device+0x40/0x60
 [] evdev_cleanup+0xac/0xc0
 [] evdev_disconnect+0x2b/0x60
 [] __input_unregister_device+0xac/0x150
 [] input_unregister_device+0x47/0x70
 [] uinput_destroy_device+0xb5/0xc0 [uinput]
 [] uinput_ioctl_handler.isra.9+0x65e/0x740 [uinput]
 [] ? do_futex+0x12b/0xad0
 [] uinput_ioctl+0x18/0x20 [uinput]
 [] do_vfs_ioctl+0x298/0x480
 [] ? security_file_ioctl+0x43/0x60
 [] SyS_ioctl+0x79/0x90
 [] entry_SYSCALL_64_fastpath+0x12/0x71

Reported-by: Rodrigo Rivas Costa 
Reported-by: Clément VUCHENER 
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=193741
Signed-off-by: Dmitry Torokhov