xref: /linux-6.15/include/linux/input/mt.h (revision 8d18fba2)
1 #ifndef _INPUT_MT_H
2 #define _INPUT_MT_H
3 
4 /*
5  * Input Multitouch Library
6  *
7  * Copyright (c) 2010 Henrik Rydberg
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  */
13 
14 #include <linux/input.h>
15 
16 #define TRKID_MAX	0xffff
17 
18 /**
19  * struct input_mt_slot - represents the state of an input MT slot
20  * @abs: holds current values of ABS_MT axes for this slot
21  */
22 struct input_mt_slot {
23 	int abs[ABS_MT_LAST - ABS_MT_FIRST + 1];
24 };
25 
26 /**
27  * struct input_mt - state of tracked contacts
28  * @trkid: stores MT tracking ID for the next contact
29  * @num_slots: number of MT slots the device uses
30  * @slot: MT slot currently being transmitted
31  * @slots: array of slots holding current values of tracked contacts
32  */
33 struct input_mt {
34 	int trkid;
35 	int num_slots;
36 	int slot;
37 	struct input_mt_slot slots[];
38 };
39 
40 static inline void input_mt_set_value(struct input_mt_slot *slot,
41 				      unsigned code, int value)
42 {
43 	slot->abs[code - ABS_MT_FIRST] = value;
44 }
45 
46 static inline int input_mt_get_value(const struct input_mt_slot *slot,
47 				     unsigned code)
48 {
49 	return slot->abs[code - ABS_MT_FIRST];
50 }
51 
52 int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots);
53 void input_mt_destroy_slots(struct input_dev *dev);
54 
55 static inline int input_mt_new_trkid(struct input_mt *mt)
56 {
57 	return mt->trkid++ & TRKID_MAX;
58 }
59 
60 static inline void input_mt_slot(struct input_dev *dev, int slot)
61 {
62 	input_event(dev, EV_ABS, ABS_MT_SLOT, slot);
63 }
64 
65 static inline bool input_is_mt_value(int axis)
66 {
67 	return axis >= ABS_MT_FIRST && axis <= ABS_MT_LAST;
68 }
69 
70 static inline bool input_is_mt_axis(int axis)
71 {
72 	return axis == ABS_MT_SLOT || input_is_mt_value(axis);
73 }
74 
75 void input_mt_report_slot_state(struct input_dev *dev,
76 				unsigned int tool_type, bool active);
77 
78 void input_mt_report_finger_count(struct input_dev *dev, int count);
79 void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
80 
81 #endif
82