Messages in this thread | | | Date | Tue, 28 Oct 2014 14:07:06 -0700 | From | Dmitry Torokhov <> | Subject | Re: [PATCH v2] input: fix BTN_TOUCH reporting in input_mt_report_pointer_emulation |
| |
On Tue, Oct 28, 2014 at 04:47:56PM -0400, Benjamin Tissoires wrote: > Hi Chung-yih, > > On Mon, Oct 27, 2014 at 6:08 AM, Chung-yih Wang <cywang@chromium.org> wrote: > > From the definition of BTN_TOUCH, BTN_TOOL_<name> and BTN_TOUCH codes > > are orthogonal. BTN_TOUCH should be zero if there is no physical contact > > happened on device. With ABS_MT_DISTANCE information, the patch uses > > touch_count and finger_count to get the final reporting code for > > BTN_TOUCH and BTN_TOOL_<name>, respectively. > > > > Signed-off-by: Chung-yih Wang <cywang@chromium.org> > > --- > > drivers/input/input-mt.c | 15 ++++++++++----- > > 1 file changed, 10 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c > > index fbe29fc..a2ab8e3 100644 > > --- a/drivers/input/input-mt.c > > +++ b/drivers/input/input-mt.c > > @@ -192,18 +192,21 @@ void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count) > > { > > struct input_mt *mt = dev->mt; > > struct input_mt_slot *oldest; > > - int oldid, count, i; > > + int oldid, i; > > + int touch_count, finger_count; > > > > if (!mt) > > return; > > > > oldest = NULL; > > oldid = mt->trkid; > > - count = 0; > > + touch_count = 0; > > + finger_count = 0; > > > > for (i = 0; i < mt->num_slots; ++i) { > > struct input_mt_slot *ps = &mt->slots[i]; > > int id = input_mt_get_value(ps, ABS_MT_TRACKING_ID); > > + int distance = input_mt_get_value(ps, ABS_MT_DISTANCE); > > I don't really like this statement, even if it works. Some devices do > not report ABS_MT_DISTANCE, and the value for them should not be > considered as '0' but 'undefined'.
I think it incidentally still 0 as we zero out memory we allocate.
> > > > > if (id < 0) > > continue; > > @@ -211,12 +214,14 @@ void input_mt_report_pointer_emulation(struct input_dev *dev, bool use_count) > > oldest = ps; > > oldid = id; > > } > > - count++; > > + finger_count++; > > + if (distance == 0) > > I'd rather test here if ABS_MT_DISTANCE is used, and then if the value is 0. > > > + touch_count++;
I do not think we should include hovering contacts into finger_count either. I.e if I have one finger touching and one finger hovering we should be emitting BTN_TOOL_FINGER and not BTN_TOOL_DOUBLETAP.
> > } > > > > - input_event(dev, EV_KEY, BTN_TOUCH, count > 0); > > + input_event(dev, EV_KEY, BTN_TOUCH, touch_count > 0); > > For the record, I *think* this will not break user space. This is used > in the touchpad part of libinput, and does not seemed to be impacted > by the change. > Adding Peter and Hans in CC who can tell us if I am assuming right. > > Cheers, > Benjamin > > > if (use_count) > > - input_mt_report_finger_count(dev, count); > > + input_mt_report_finger_count(dev, finger_count); > > > > if (oldest) { > > int x = input_mt_get_value(oldest, ABS_MT_POSITION_X); > > -- > > 2.1.2 > >
Thanks.
-- Dmitry
| |