1 files changed, 94 insertions, 22 deletions

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 1bda3a4bd71f..f6f882da6267 100644
--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -25,8 +25,16 @@
                                         EV_KEY, (c))
 
 struct ntrig_data {
-        __s32 x, y, id, w, h;
-        bool reading_a_point, found_contact_id;
+        /* Incoming raw values for a single contact */
+        __u16 x, y, w, h;
+        __u16 id;
+        __u8 confidence;
+
+        bool reading_mt;
+        __u8 first_contact_confidence;
+
+        __u8 mt_footer[4];
+        __u8 mt_foot_count;
 };
 
 /*
@@ -39,8 +47,8 @@ static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
                 struct hid_field *field, struct hid_usage *usage,
                 unsigned long **bit, int *max)
 {
-        /* No special mappings needed for the pen */
-        if (field->application == HID_DG_PEN)
+        /* No special mappings needed for the pen and single touch */
+        if (field->physical)
                 return 0;
 
         switch (usage->hid & HID_USAGE_PAGE) {
@@ -66,18 +74,12 @@ static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
         case HID_UP_DIGITIZER:
                 switch (usage->hid) {
                 /* we do not want to map these for now */
-                case HID_DG_CONTACTID: /* value is useless */
+                case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */
                 case HID_DG_INPUTMODE:
                 case HID_DG_DEVICEINDEX:
-                case HID_DG_CONTACTCOUNT:
                 case HID_DG_CONTACTMAX:
                         return -1;
 
-                /* original mapping by Rafi Rubin */
-                case HID_DG_CONFIDENCE:
-                        nt_map_key_clear(BTN_TOOL_DOUBLETAP);
-                        return 1;
-
                 /* width/height mapped on TouchMajor/TouchMinor/Orientation */
                 case HID_DG_WIDTH:
                         hid_map_usage(hi, usage, bit, max,
@@ -104,8 +106,8 @@ static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
                 struct hid_field *field, struct hid_usage *usage,
                 unsigned long **bit, int *max)
 {
-        /* No special mappings needed for the pen */
-        if (field->application == HID_DG_PEN)
+        /* No special mappings needed for the pen and single touch */
+        if (field->physical)
                 return 0;
 
         if (usage->type == EV_KEY || usage->type == EV_REL
@@ -133,17 +135,24 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field,
 
         if (hid->claimed & HID_CLAIMED_INPUT) {
                 switch (usage->hid) {
+                case 0xff000001:
+                        /* Tag indicating the start of a multitouch group */
+                        nd->reading_mt = 1;
+                        nd->first_contact_confidence = 0;
+                        break;
+                case HID_DG_CONFIDENCE:
+                        nd->confidence = value;
+                        break;
                 case HID_GD_X:
                         nd->x = value;
-                        nd->reading_a_point = 1;
+                        /* Clear the contact footer */
+                        nd->mt_foot_count = 0;
                         break;
                 case HID_GD_Y:
                         nd->y = value;
                         break;
                 case HID_DG_CONTACTID:
                         nd->id = value;
-                        /* we receive this only when in multitouch mode */
-                        nd->found_contact_id = 1;
                         break;
                 case HID_DG_WIDTH:
                         nd->w = value;
@@ -155,7 +164,7 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field,
                          * report received in a finger event. We want
                          * to emit a normal (X, Y) position
                          */
-                        if (!nd->found_contact_id) {
+                        if (!nd->reading_mt) {
                                 input_event(input, EV_ABS, ABS_X, nd->x);
                                 input_event(input, EV_ABS, ABS_Y, nd->y);
                         }
@@ -167,10 +176,34 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field,
                          * this usage tells if the contact point is real
                          * or a placeholder
                          */
-                        if (!nd->reading_a_point || value != 1)
+
+                        /* Shouldn't get more than 4 footer packets, so skip */
+                        if (nd->mt_foot_count >= 4)
+                                break;
+
+                        nd->mt_footer[nd->mt_foot_count++] = value;
+
+                        /* if the footer isn't complete break */
+                        if (nd->mt_foot_count != 4)
+                                break;
+
+                        /* Pen activity signal, trigger end of touch. */
+                        if (nd->mt_footer[2]) {
+                                nd->confidence = 0;
+                                break;
+                        }
+
+                        /* If the contact was invalid */
+                        if (!(nd->confidence && nd->mt_footer[0])
+                                        || nd->w <= 250
+                                        || nd->h <= 190) {
+                                nd->confidence = 0;
                                 break;
+                        }
+
                         /* emit a normal (X, Y) for the first point only */
                         if (nd->id == 0) {
+                                nd->first_contact_confidence = nd->confidence;
                                 input_event(input, EV_ABS, ABS_X, nd->x);
                                 input_event(input, EV_ABS, ABS_Y, nd->y);
                         }
@@ -192,8 +225,39 @@ static int ntrig_event (struct hid_device *hid, struct hid_field *field,
                                                 ABS_MT_TOUCH_MINOR, nd->w);
                         }
                         input_mt_sync(field->hidinput->input);
-                        nd->reading_a_point = 0;
-                        nd->found_contact_id = 0;
+                        break;
+
+                case HID_DG_CONTACTCOUNT: /* End of a multitouch group */
+                        if (!nd->reading_mt)
+                                break;
+
+                        nd->reading_mt = 0;
+
+                        if (nd->first_contact_confidence) {
+                                switch (value) {
+                                case 0: /* for single touch devices */
+                                case 1:
+                                        input_report_key(input,
+                                                        BTN_TOOL_DOUBLETAP, 1);
+                                        break;
+                                case 2:
+                                        input_report_key(input,
+                                                        BTN_TOOL_TRIPLETAP, 1);
+                                        break;
+                                case 3:
+                                default:
+                                        input_report_key(input,
+                                                        BTN_TOOL_QUADTAP, 1);
+                                }
+                                input_report_key(input, BTN_TOUCH, 1);
+                        } else {
+                                input_report_key(input,
+                                                BTN_TOOL_DOUBLETAP, 0);
+                                input_report_key(input,
+                                                BTN_TOOL_TRIPLETAP, 0);
+                                input_report_key(input,
+                                                BTN_TOOL_QUADTAP, 0);
+                        }
                         break;
 
                 default:
@@ -224,8 +288,8 @@ static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
                 dev_err(&hdev->dev, "cannot allocate N-Trig data\n");
                 return -ENOMEM;
         }
-        nd->reading_a_point = 0;
-        nd->found_contact_id = 0;
+
+        nd->reading_mt = 0;
         hid_set_drvdata(hdev, nd);
 
         ret = hid_parse(hdev);
@@ -248,6 +312,14 @@ static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
                         input->name = "N-Trig Pen";
                         break;
                 case HID_DG_TOUCHSCREEN:
+                        __clear_bit(BTN_TOOL_PEN, input->keybit);
+                        /*
+                         * A little something special to enable
+                         * two and three finger taps.
+                         */
+                        __set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
+                        __set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
+                        __set_bit(BTN_TOOL_QUADTAP, input->keybit);
                         /*
                          * The physical touchscreen (single touch)
                          * input has a value for physical, whereas