mt.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2#ifndef _INPUT_MT_H
  3#define _INPUT_MT_H
  4
  5/*
  6 * Input Multitouch Library
  7 *
  8 * Copyright (c) 2010 Henrik Rydberg
  9 */
 10
 11#include <linux/input.h>
 12
 13#define TRKID_MAX	0xffff
 14
 15#define INPUT_MT_POINTER	0x0001	/* pointer device, e.g. trackpad */
 16#define INPUT_MT_DIRECT		0x0002	/* direct device, e.g. touchscreen */
 17#define INPUT_MT_DROP_UNUSED	0x0004	/* drop contacts not seen in frame */
 18#define INPUT_MT_TRACK		0x0008	/* use in-kernel tracking */
 19#define INPUT_MT_SEMI_MT	0x0010	/* semi-mt device, finger count handled manually */
 20#define INPUT_MT_TOTAL_FORCE	0x0020	/* calculate total force from slots pressure */
 21
 22/**
 23 * struct input_mt_slot - represents the state of an input MT slot
 24 * @abs: holds current values of ABS_MT axes for this slot
 25 * @frame: last frame at which input_mt_report_slot_state() was called
 26 * @key: optional driver designation of this slot
 27 */
 28struct input_mt_slot {
 29	int abs[ABS_MT_LAST - ABS_MT_FIRST + 1];
 30	unsigned int frame;
 31	unsigned int key;
 32};
 33
 34/**
 35 * struct input_mt - state of tracked contacts
 36 * @trkid: stores MT tracking ID for the next contact
 37 * @num_slots: number of MT slots the device uses
 38 * @slot: MT slot currently being transmitted
 39 * @flags: input_mt operation flags
 40 * @frame: increases every time input_mt_sync_frame() is called
 41 * @red: reduced cost matrix for in-kernel tracking
 42 * @slots: array of slots holding current values of tracked contacts
 43 */
 44struct input_mt {
 45	int trkid;
 46	int num_slots;
 47	int slot;
 48	unsigned int flags;
 49	unsigned int frame;
 50	int *red;
 51	struct input_mt_slot slots[] __counted_by(num_slots);
 52};
 53
 54static inline void input_mt_set_value(struct input_mt_slot *slot,
 55				      unsigned code, int value)
 56{
 57	slot->abs[code - ABS_MT_FIRST] = value;
 58}
 59
 60static inline int input_mt_get_value(const struct input_mt_slot *slot,
 61				     unsigned code)
 62{
 63	return slot->abs[code - ABS_MT_FIRST];
 64}
 65
 66static inline bool input_mt_is_active(const struct input_mt_slot *slot)
 67{
 68	return input_mt_get_value(slot, ABS_MT_TRACKING_ID) >= 0;
 69}
 70
 71static inline bool input_mt_is_used(const struct input_mt *mt,
 72				    const struct input_mt_slot *slot)
 73{
 74	return slot->frame == mt->frame;
 75}
 76
 77int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
 78			unsigned int flags);
 79void input_mt_destroy_slots(struct input_dev *dev);
 80
 81static inline int input_mt_new_trkid(struct input_mt *mt)
 82{
 83	return mt->trkid++ & TRKID_MAX;
 84}
 85
 86static inline void input_mt_slot(struct input_dev *dev, int slot)
 87{
 88	input_event(dev, EV_ABS, ABS_MT_SLOT, slot);
 89}
 90
 91static inline bool input_is_mt_value(int axis)
 92{
 93	return axis >= ABS_MT_FIRST && axis <= ABS_MT_LAST;
 94}
 95
 96static inline bool input_is_mt_axis(int axis)
 97{
 98	return axis == ABS_MT_SLOT || input_is_mt_value(axis);
 99}
100
101bool input_mt_report_slot_state(struct input_dev *dev,
102				unsigned int tool_type, bool active);
103
104static inline void input_mt_report_slot_inactive(struct input_dev *dev)
105{
106	input_mt_report_slot_state(dev, 0, false);
107}
108
109void input_mt_report_finger_count(struct input_dev *dev, int count);
110void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
111void input_mt_drop_unused(struct input_dev *dev);
112
113void input_mt_sync_frame(struct input_dev *dev);
114
115/**
116 * struct input_mt_pos - contact position
117 * @x: horizontal coordinate
118 * @y: vertical coordinate
119 */
120struct input_mt_pos {
121	s16 x, y;
122};
123
124int input_mt_assign_slots(struct input_dev *dev, int *slots,
125			  const struct input_mt_pos *pos, int num_pos,
126			  int dmax);
127
128int input_mt_get_slot_by_key(struct input_dev *dev, int key);
129
130#endif