Sometimes it is useful to observe (and maybe modify) data coming from
an input device, but only do that if there are other users of such input
device. An example is touchpad switching functionality on Lenovo IdeaPad
Z570 where it is desirable to suppress events coming from the touchpad
if user toggles touchpad on/off button (on this laptop the firmware does
not stop the device).
Introduce notion of passive observers for input handlers to solve this
issue. An input handler marked as passive observer behaves exactly like
any other input handler or filter, but with one exception: it does not
open/start underlying input device when attaching to it.
Link: https://lore.kernel.org/r/ZxlEROX7bMo5cbZP@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Commit d469647baf ("Input: simplify event handling logic") introduced
code that would set handler->events() method to either
input_handler_events_filter() or input_handler_events_default() or
input_handler_events_null(), depending on the kind of input handler
(a filter or a regular one) we are dealing with. Unfortunately this
breaks cases when we try to re-register the same filter (as is the case
with sysrq handler): after initial registration the handler will have 2
event handling methods defined, and will run afoul of the check in
input_handler_check_methods():
input: input_handler_check_methods: only one event processing method can be defined (sysrq)
sysrq: Failed to register input handler, error -22
Fix this by adding handle_events() method to input_handle structure and
setting it up when registering a new input handle according to event
handling methods defined in associated input_handler structure, thus
avoiding modifying the input_handler structure.
Reported-by: "Ned T. Crigler" <crigler@gmail.com>
Reported-by: Christian Heusel <christian@heusel.eu>
Tested-by: "Ned T. Crigler" <crigler@gmail.com>
Tested-by: Peter Seiderer <ps.report@gmx.net>
Fixes: d469647baf ("Input: simplify event handling logic")
Link: https://lore.kernel.org/r/Zx2iQp6csn42PJA7@xavtug
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct ff_device.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20231006201739.work.350-kees@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <patrikf@chromium.org>
Co-developed-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Link: https://lore.kernel.org/r/20200608112211.12125-8-andrzej.p@collabora.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <michal.vokac@ysoft.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <atifniyaz@google.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let's allow matching input devices on their property bits, both in-kernel
and when generating module aliases.
Tested-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <roderick.colenbrander@sony.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This patch fix a double word "is is" found in in
Documentation/DocBook/device-drivers.xml.
It is because the file was created from comments in sources,
so I have to fix the double words in include/linux/input.h
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Add new function input_enable_softrepeat() that allows drivers to
initialize their own values for input_dev->rep[REP_DELAY] and
input_dev->rep[REP_PERIOD], but also use the software autorepeat
functionality from input.c.
For example, a HID driver could do:
static void xyz_input_configured(struct hid_device *hid,
struct hid_input *hidinput)
{
input_enable_softrepeat(hidinput->input, 400, 100);
}
static struct hid_driver xyz_driver = {
.input_configured = xyz_input_configured,
}
Signed-off-by: Petri Gynther <pgynther@google.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
There is a demand from driver's writers to use managed devices framework
for their drivers. Unfortunately up to this moment input devices did not
provide support for managed devices and that lead to mixing two styles
of resource management which usually introduced more bugs, such as
manually unregistering input device but relying in devres to free
interrupt handler which (unless device is properly shut off) can cause
ISR to reference already freed memory.
This change introduces devm_input_allocate_device() that will allocate
managed instance of input device so that driver writers who prefer
using devm_* framework do not have to mix 2 styles.
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Extend the amount of character devices, such as eventX, mouseX and jsX,
from a hard limit of 32 per input handler to about 1024 shared across
all handlers.
To be compatible with legacy installations input handlers will start
creating char devices with minors in their legacy range, however once
legacy range is exhausted they will start allocating minors from the
dynamic range 256-1024.
Reviewed-by: David Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
On heavy event loads, such as a multitouch driver, the irqsoff latency
can be as high as 250 us. By accumulating a frame worth of data
before passing it on, the latency can be dramatically reduced. As a
side effect, the special EV_SYN handling can be removed, since the
frame is now atomic.
This patch adds the events() handler callback and uses it if it
exists. The latency is improved by 50 us even without the callback.
Cc: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Move all MT-related things to a separate place. This saves some
bytes for non-mt input devices, and prepares for new MT features.
Reviewed-and-tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
