leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Input: ALPS - handle 0-pressure 1F events

Browse Source 
While a button is held SS5 hardware will give us single-finger packets
with x, y, and pressure equal to zero. This causes annoying jumps in
pointer position if a touch is released while the button is held. Handle
this by claiming zero contacts to ensure that no position events are
provided to the user.

Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Ben Gamari <ben@smart-cactus.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Ben Gamari 2016-10-04 11:40:44 -07:00 committed by Dmitry Torokhov
parent 4777ac220c
commit a831776323
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/input/mouse/alps.c
View File

@ -1198,7 +1198,13 @@ static int alps_decode_ss4_v2(struct alps_fields *f,
f->mt[0].x = SS4_1F_X_V2(p);
f->mt[0].y = SS4_1F_Y_V2(p);
f->pressure = ((SS4_1F_Z_V2(p)) * 2) & 0x7f;
f->fingers = 1;
/*
* When a button is held the device will give us events
* with x, y, and pressure of 0. This causes annoying jumps
* if a touch is released while the button is held.
* Handle this by claiming zero contacts.
*/
f->fingers = f->pressure > 0 ? 1 : 0;
f->first_mp = 0;
f->is_mp = 0;
break;