1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _INPUT_MT_H
#define _INPUT_MT_H

/*
 * Input Multitouch Library
 *
 * Copyright (c) 2010 Henrik Rydberg
 */

#include <linux/input.h>

#define TRKID_MAX	0xffff

#define INPUT_MT_POINTER	0x0001	/* pointer device, e.g. trackpad */
#define INPUT_MT_DIRECT		0x0002	/* direct device, e.g. touchscreen */
#define INPUT_MT_DROP_UNUSED	0x0004	/* drop contacts not seen in frame */
#define INPUT_MT_TRACK		0x0008	/* use in-kernel tracking */
#define INPUT_MT_SEMI_MT	0x0010	/* semi-mt device, finger count handled manually */

/**
 * struct input_mt_slot - represents the state of an input MT slot
 * @abs: holds current values of ABS_MT axes for this slot
 * @frame: last frame at which input_mt_report_slot_state() was called
 * @key: optional driver designation of this slot
 */
struct input_mt_slot {
	int abs[ABS_MT_LAST - ABS_MT_FIRST + 1];
	unsigned int frame;
	unsigned int key;
};

/**
 * struct input_mt - state of tracked contacts
 * @trkid: stores MT tracking ID for the next contact
 * @num_slots: number of MT slots the device uses
 * @slot: MT slot currently being transmitted
 * @flags: input_mt operation flags
 * @frame: increases every time input_mt_sync_frame() is called
 * @red: reduced cost matrix for in-kernel tracking
 * @slots: array of slots holding current values of tracked contacts
 */
struct input_mt {
	int trkid;
	int num_slots;
	int slot;
	unsigned int flags;
	unsigned int frame;
	int *red;
	struct input_mt_slot slots[] __counted_by(num_slots);
};

static inline void input_mt_set_value(struct input_mt_slot *slot,
				      unsigned code, int value)
{
	slot->abs[code - ABS_MT_FIRST] = value;
}

static inline int input_mt_get_value(const struct input_mt_slot *slot,
				     unsigned code)
{
	return slot->abs[code - ABS_MT_FIRST];
}

static inline bool input_mt_is_active(const struct input_mt_slot *slot)
{
	return input_mt_get_value(slot, ABS_MT_TRACKING_ID) >= 0;
}

static inline bool input_mt_is_used(const struct input_mt *mt,
				    const struct input_mt_slot *slot)
{
	return slot->frame == mt->frame;
}

int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
			unsigned int flags);
void input_mt_destroy_slots(struct input_dev *dev);

static inline int input_mt_new_trkid(struct input_mt *mt)
{
	return mt->trkid++ & TRKID_MAX;
}

static inline void input_mt_slot(struct input_dev *dev, int slot)
{
	input_event(dev, EV_ABS, ABS_MT_SLOT, slot);
}

static inline bool input_is_mt_value(int axis)
{
	return axis >= ABS_MT_FIRST && axis <= ABS_MT_LAST;
}

static inline bool input_is_mt_axis(int axis)
{
	return axis == ABS_MT_SLOT || input_is_mt_value(axis);
}

bool input_mt_report_slot_state(struct input_dev *dev,
				unsigned int tool_type, bool active);

static inline void input_mt_report_slot_inactive(struct input_dev *dev)
{
	input_mt_report_slot_state(dev, 0, false);
}

void input_mt_report_finger_count(struct input_dev *dev, int count);
void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
void input_mt_drop_unused(struct input_dev *dev);

void input_mt_sync_frame(struct input_dev *dev);

/**
 * struct input_mt_pos - contact position
 * @x: horizontal coordinate
 * @y: vertical coordinate
 */
struct input_mt_pos {
	s16 x, y;
};

int input_mt_assign_slots(struct input_dev *dev, int *slots,
			  const struct input_mt_pos *pos, int num_pos,
			  int dmax);

int input_mt_get_slot_by_key(struct input_dev *dev, int key);

#endif
我想我會開始想念你 可是我剛剛才遇見了你