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