GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Input: MT - Add in-kernel tracking

Browse source 
With the INPUT_MT_TRACK flag set, the function input_mt_assign_slots()
can be used to match a new set of contacts against the currently used
slots. The algorithm used is based on Lagrange relaxation, and performs
very well in practice; slower than mtdev for a few corner cases, but
faster in most commonly occuring cases.

Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
This commit is contained in:
Henrik Rydberg 2012-08-12 20:47:05 +02:00
parent 55e49089f4
commit 7c1a87897c
2 changed files with 163 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

21
include/linux/input/mt.h
View file

@ -18,6 +18,8 @@
#define INPUT_MT_POINTER 0x0001 /* pointer device, e.g. trackpad */
#define INPUT_MT_DIRECT 0x0002 /* direct device, e.g. touchscreen */
#define INPUT_MT_DROP_UNUSED 0x0004 /* drop contacts not seen in frame */
#define INPUT_MT_TRACK 0x0008 /* use in-kernel tracking */
/**
* struct input_mt_slot - represents the state of an input MT slot
* @abs: holds current values of ABS_MT axes for this slot
@ -35,6 +37,7 @@ struct input_mt_slot {
* @slot: MT slot currently being transmitted
* @flags: input_mt operation flags
* @frame: increases every time input_mt_sync_frame() is called
* @red: reduced cost matrix for in-kernel tracking
* @slots: array of slots holding current values of tracked contacts
*/
struct input_mt {
@ -43,6 +46,7 @@ struct input_mt {
int slot;
unsigned int flags;
unsigned int frame;
int *red;
struct input_mt_slot slots[];
};
@ -58,6 +62,11 @@ static inline int input_mt_get_value(const struct input_mt_slot *slot,
return slot->abs[code - ABS_MT_FIRST];
}
static inline bool input_mt_is_active(const struct input_mt_slot *slot)
{
return input_mt_get_value(slot, ABS_MT_TRACKING_ID) >= 0;
}
int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots,
unsigned int flags);
void input_mt_destroy_slots(struct input_dev *dev);
@ -90,4 +99,16 @@ void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count);
void input_mt_sync_frame(struct input_dev *dev);
/**
* struct input_mt_pos - contact position
* @x: horizontal coordinate
* @y: vertical coordinate
*/
struct input_mt_pos {
s16 x, y;
};
int input_mt_assign_slots(struct input_dev *dev, int *slots,
const struct input_mt_pos *pos, int num_pos);
#endif