LXR linux/include/linux/input/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
  21/**
  22 * struct input_mt_slot - represents the state of an input MT slot
  23 * @abs: holds current values of ABS_MT axes for this slot
  24 * @frame: last frame at which input_mt_report_slot_state() was called
  25 * @key: optional driver designation of this slot
  26 */
  27struct input_mt_slot {
  28        int abs[ABS_MT_LAST - ABS_MT_FIRST + 1];
  29        unsigned int frame;
  30        unsigned int key;
  31};
  32
  33/**
  34 * struct input_mt - state of tracked contacts
  35 * @trkid: stores MT tracking ID for the next contact
  36 * @num_slots: number of MT slots the device uses
  37 * @slot: MT slot currently being transmitted
  38 * @flags: input_mt operation flags
  39 * @frame: increases every time input_mt_sync_frame() is called
  40 * @red: reduced cost matrix for in-kernel tracking
  41 * @slots: array of slots holding current values of tracked contacts
  42 */
  43struct input_mt {
  44        int trkid;
  45        int num_slots;
  46        int slot;
  47        unsigned int flags;
  48        unsigned int frame;
  49        int *red;
  50        struct input_mt_slot slots[];
  51};
  52
  53static inline void input_mt_set_value(struct input_mt_slot *slot,
  54                                      unsigned code, int value)
  55{
  56        slot->abs[code - ABS_MT_FIRST] = value;
  57}
  58
  59static inline int input_mt_get_value(const struct input_mt_slot *slot,
  60                                     unsigned code)
  61{
  62        return slot->abs[code - ABS_MT_FIRST];
  63}
  64
  65static inline bool input_mt_is_active(const struct input_mt_slot *slot)
  66{
  67        return input_mt_get_value(slot, ABS_MT_TRACKING_ID) >= 0;
  68}
  69
  70static inline bool input_mt_is_used(const struct input_mt *mt,
  71                                    const struct input_mt_slot *slot)
  72{
  73        return slot->frame == mt->frame;
  74}
  75
  76int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
  77                        unsigned int flags);
  78void input_mt_destroy_slots(struct input_dev *dev);
  79
  80static inline int input_mt_new_trkid(struct input_mt *mt)
  81{
  82        return mt->trkid++ & TRKID_MAX;
  83}
  84
  85static inline void input_mt_slot(struct input_dev *dev, int slot)
  86{
  87        input_event(dev, EV_ABS, ABS_MT_SLOT, slot);
  88}
  89
  90static inline bool input_is_mt_value(int axis)
  91{
  92        return axis >= ABS_MT_FIRST && axis <= ABS_MT_LAST;
  93}
  94
  95static inline bool input_is_mt_axis(int axis)
  96{
  97        return axis == ABS_MT_SLOT || input_is_mt_value(axis);
  98}
  99
 100bool input_mt_report_slot_state(struct input_dev *dev,
 101                                unsigned int tool_type, bool active);
 102
 103static inline void input_mt_report_slot_inactive(struct input_dev *dev)
 104{
 105        input_mt_report_slot_state(dev, 0, false);
 106}
 107
 108void input_mt_report_finger_count(struct input_dev *dev, int count);
 109void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
 110void input_mt_drop_unused(struct input_dev *dev);
 111
 112void input_mt_sync_frame(struct input_dev *dev);
 113
 114/**
 115 * struct input_mt_pos - contact position
 116 * @x: horizontal coordinate
 117 * @y: vertical coordinate
 118 */
 119struct input_mt_pos {
 120        s16 x, y;
 121};
 122
 123int input_mt_assign_slots(struct input_dev *dev, int *slots,
 124                          const struct input_mt_pos *pos, int num_pos,
 125                          int dmax);
 126
 127int input_mt_get_slot_by_key(struct input_dev *dev, int key);
 128
 129#endif
 130