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  */
  30 struct 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  */
  46 struct 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
  56 static 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
  62 static 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
  68 static 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
  73 static 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
  79 int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
  80                         unsigned int flags);
  81 void input_mt_destroy_slots(struct input_dev *dev);
  82
  83 static inline int input_mt_new_trkid(struct input_mt *mt)
  84 {
  85         return mt->trkid++ & TRKID_MAX;
  86 }
  87
  88 static inline void input_mt_slot(struct input_dev *dev, int slot)
  89 {
  90         input_event(dev, EV_ABS, ABS_MT_SLOT, slot);
  91 }
  92
  93 static inline bool input_is_mt_value(int axis)
  94 {
  95         return axis >= ABS_MT_FIRST && axis <= ABS_MT_LAST;
  96 }
  97
  98 static inline bool input_is_mt_axis(int axis)
  99 {
 100         return axis == ABS_MT_SLOT || input_is_mt_value(axis);
 101 }
 102
 103 void input_mt_report_slot_state(struct input_dev *dev,
 104                                 unsigned int tool_type, bool active);
 105
 106 void input_mt_report_finger_count(struct input_dev *dev, int count);
 107 void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
 108 void input_mt_drop_unused(struct input_dev *dev);
 109
 110 void 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  */
 117 struct input_mt_pos {
 118         s16 x, y;
 119 };
 120
 121 int input_mt_assign_slots(struct input_dev *dev, int *slots,
 122                           const struct input_mt_pos *pos, int num_pos,
 123                           int dmax);
 124
 125 int input_mt_get_slot_by_key(struct input_dev *dev, int key);
 126
 127 #endif