LXR linux/include/linux/input/mt.h

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