Comply with MT syncronization protocol

The latest semantic clarifications in the kernel MT protocol allow
SYN_MT_REPORT to be sent without actually sending any finger data. Add
a mask to the hardware data so that the data actually read can be
tracked.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

1 files changed, 36 insertions, 13 deletions

diff --git a/src/hwdata.c b/src/hwdata.c
index 9e384dc..e76bcd8 100644
--- a/src/hwdata.c
+++ b/src/hwdata.c
@@ -26,17 +26,42 @@ void init_hwdata(struct HWData *hw)
         memset(hw, 0, sizeof(struct HWData));
 }
 
+static void set_value(struct HWData *hw, int code, int value)
+{
+        if (hw->nread < DIM_FINGER) {
+                (&hw->finger[hw->nread].touch_major)[code] = value;
+                SETBIT(hw->mread[hw->nread], code);
+        }
+}
+
+static void accept_finger(struct HWData *hw)
+{
+        if (hw->nread < DIM_FINGER &&
+            GETBIT(hw->mread[hw->nread], BIT_MT_POSITION_X) &&
+            GETBIT(hw->mread[hw->nread], BIT_MT_POSITION_Y)) {
+                hw->mask[hw->nread] = hw->mread[hw->nread];
+                hw->nfinger = ++hw->nread;
+        }
+        if (hw->nread < DIM_FINGER)
+                hw->mread[hw->nread] = 0;
+}
+
+static void accept_packet(struct HWData *hw)
+{
+        hw->nread = 0;
+        hw->mread[hw->nread] = 0;
+}
+
 int read_hwdata(struct HWData *hw, const struct input_event* ev)
 {
         switch (ev->type) {
         case EV_SYN:
                 switch (ev->code) {
                 case SYN_REPORT:
-                        hw->nread = 0;
+                        accept_packet(hw);
                         return 1;
                 case SYN_MT_REPORT:
-                        hw->nread++;
-                        hw->nfinger = hw->nread;
+                        accept_finger(hw);
                         break;
                 }
                 break;
@@ -63,32 +88,30 @@ int read_hwdata(struct HWData *hw, const struct input_event* ev)
                 }
                 break;
         case EV_ABS:
-                if (hw->nread == DIM_FINGER)
-                        break;
                 switch (ev->code) {
                 case ABS_MT_TOUCH_MAJOR:
-                        hw->finger[hw->nread].touch_major = ev->value;
+                        set_value(hw, BIT_MT_TOUCH_MAJOR, ev->value);
                         break;
                 case ABS_MT_TOUCH_MINOR:
-                        hw->finger[hw->nread].touch_minor = ev->value;
+                        set_value(hw, BIT_MT_TOUCH_MINOR, ev->value);
                         break;
                 case ABS_MT_WIDTH_MAJOR:
-                        hw->finger[hw->nread].width_major = ev->value;
+                        set_value(hw, BIT_MT_WIDTH_MAJOR, ev->value);
                         break;
                 case ABS_MT_WIDTH_MINOR:
-                        hw->finger[hw->nread].width_minor = ev->value;
+                        set_value(hw, BIT_MT_WIDTH_MINOR, ev->value);
                         break;
                 case ABS_MT_ORIENTATION:
-                        hw->finger[hw->nread].orientation = ev->value;
+                        set_value(hw, BIT_MT_ORIENTATION, ev->value);
                         break;
                 case ABS_MT_PRESSURE:
-                        hw->finger[hw->nread].pressure = ev->value;
+                        set_value(hw, BIT_MT_PRESSURE, ev->value);
                         break;
                 case ABS_MT_POSITION_X:
-                        hw->finger[hw->nread].position_x = ev->value;
+                        set_value(hw, BIT_MT_POSITION_X, ev->value);
                         break;
                 case ABS_MT_POSITION_Y:
-                        hw->finger[hw->nread].position_y = ev->value;
+                        set_value(hw, BIT_MT_POSITION_Y, ev->value);
                         break;
                 }
                 break;