linux-toradex.git/include/linux/input/mt.h, branch v6.16-rc6

Input: mt - annotate struct input_mt with __counted_by

2023-09-30T16:24:17+00:00

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 checking 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 input_mt.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Signed-off-by: Kees Cook 
Reviewed-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20230922175036.work.762-kees@kernel.org
Signed-off-by: Dmitry Torokhov

Input: introduce input_mt_report_slot_inactive()

2020-05-12T20:18:26+00:00

input_mt_report_slot_state() ignores "tool" argument when the slot is
closed, which has caused a bit of confusion. Let's introduce
input_mt_report_slot_inactive() to report inactive slot state.

Suggested-by: Dmitry Torokhov 
Signed-off-by: Jiada Wang 
Link: https://lore.kernel.org/r/20200508055656.96389-2-jiada_wang@mentor.com
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: make input_report_slot_state() return boolean

2018-06-11T17:21:06+00:00

Let's make input_report_slot_state() return boolean representing whether
the contact is active or not. This will allow writing code like:

	if (input_mt_report_slot_state(input, obj->mt_tool,
					obj->type != RMI_2D_OBJECT_NONE) {

		input_event(sensor->input, EV_ABS, ABS_MT_POSITION_X, obj->x);
		input_event(sensor->input, EV_ABS, ABS_MT_POSITION_Y, obj->y);
		...
	}

instead of:

	input_mt_report_slot_state(input, obj->mt_tool,
				   obj->type != RMI_2D_OBJECT_NONE);
	if (obj->type != RMI_2D_OBJECT_NONE) {
		input_event(sensor->input, EV_ABS, ABS_MT_POSITION_X, obj->x);
		input_event(sensor->input, EV_ABS, ABS_MT_POSITION_Y, obj->y);
		...
	}

Reviewed-by: Henrik Rydberg 
Acked-by: Benjamin Tissoires 
Signed-off-by: Dmitry Torokhov

Input: MT - add support for balanced slot assignment

2015-02-01T19:50:35+00:00

Some devices are not fast enough to differentiate between a fast-moving
contact and a new contact. This problem cannot be fully resolved because
information is truly missing, but it is possible to safe-guard against
obvious mistakes by restricting movement with a maximum displacement.

The new problem formulation for dmax > 0 cannot benefit from the speedup
for positive definite matrices, but since the convergence is faster, the
result is about the same. For a handful of contacts, the latency difference
is truly negligible.

Suggested-by: Benjamin Tissoires 
Tested-by: Benjamin Tissoires 
Signed-off-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: MT - make slot cleanup callable outside mt_sync_frame()

2014-08-08T06:37:07+00:00

Some semi-mt drivers use the slots in a manual way, but may still
want to call parts of the frame synchronization logic. This patch
makes input_mt_drop_unused callable from those drivers.

Signed-off-by: Henrik Rydberg 
Reviewed-by: Benson Leung 
Signed-off-by: Dmitry Torokhov

Input: MT - handle semi-mt devices in core

2013-04-08T04:02:32+00:00

Most semi-mt drivers use the slots in a manual way, but really only
need to treat the finger count manually. With this patch, a semi-mt
driver may use the input-mt core for everything else.

Signed-off-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: mt: add input_mt_is_used

2012-11-15T09:16:56+00:00

This patch extracts the test (slot->frame == mt->frame) so that it can
be used in third party drivers.

Signed-off-by: Benjamin Tissoires 
Reviewed-by: Henrik Rydberg 
Signed-off-by: Jiri Kosina

Input: MT - Get slot by key

2012-09-19T17:50:19+00:00

Some devices use an internal key for tracking which cannot be directly
mapped to slots. This patch provides a key-to-slot mapping, which can
be used by drivers of such devices.

Reviewed-and-tested-by: Benjamin Tissoires 
Acked-by: Dmitry Torokhov 
Signed-off-by: Henrik Rydberg

Input: MT - Add in-kernel tracking

2012-09-19T17:50:19+00:00

With the INPUT_MT_TRACK flag set, the function input_mt_assign_slots()
can be used to match a new set of contacts against the currently used
slots. The algorithm used is based on Lagrange relaxation, and performs
very well in practice; slower than mtdev for a few corner cases, but
faster in most commonly occuring cases.

Tested-by: Benjamin Tissoires 
Acked-by: Dmitry Torokhov 
Signed-off-by: Henrik Rydberg