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, e.g.
hovering finger, happened on device. The patch uses touch_count and finger_count
to get the final reporting code for BTN_TOUCH and BTN_TOOL_<name>,
respectively. In addition, as there are some hard-coded pressure thresholds
defined in touch device's driver classes, 'touch_threshold' is introduced into
struct input_dev in order to tell if a finger is considered as a touch one in
input_mt_report_pointer_emulation().

---
 drivers/input/input-mt.c | 15 ++++++++++-----
 include/linux/input.h    |  2 ++
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c
index fbe29fc..47e41d6 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 pressure = input_mt_get_value(ps, ABS_MT_PRESSURE);
 
                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 (pressure > dev->touch_threshold)
+                       touch_count++;
        }
 
-       input_event(dev, EV_KEY, BTN_TOUCH, count > 0);
+       input_event(dev, EV_KEY, BTN_TOUCH, touch_count > 0);
        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);
diff --git a/include/linux/input.h b/include/linux/input.h
index 82ce323..5b2739d 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -187,6 +187,8 @@ struct input_dev {
        struct input_value *vals;
 
        bool devres_managed;
+
+       unsigned int touch_threshold;
 };
 #define to_input_dev(d) container_of(d, struct input_dev, dev)
 
-- 
2.0.0.526.g5318336

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