Detection of multitouch devices

This patch makes nothing except detecting multitouch devices and putting
this detection in the log.

Signed-off-by: Benjamin Tissoires <tissoire@cena.fr>

2 files changed, 41 insertions, 1 deletions

diff --git a/src/evdev.c b/src/evdev.c
index 3051462..0e1577f 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -118,6 +118,7 @@ static Atom prop_calibration = 0;
 static Atom prop_swap = 0;
 static Atom prop_axis_label = 0;
 static Atom prop_btn_label = 0;
+static Atom prop_multitouch = 0;
 #endif
 
 /* All devices the evdev driver has allocated and knows about.
@@ -349,6 +350,8 @@ EvdevQueueButtonClicks(InputInfoPtr pInfo, int button, int count)
 #define ABS_X_VALUE 0x1
 #define ABS_Y_VALUE 0x2
 #define ABS_VALUE   0x4
+#define ABS_MT_X_VALUE   0x8
+#define ABS_MT_Y_VALUE   0x16
 /**
  * Take the valuators and process them accordingly.
  */
@@ -554,6 +557,10 @@ EvdevProcessAbsoluteMotionEvent(InputInfoPtr pInfo, struct input_event *ev)
         pEvdev->abs |= ABS_X_VALUE;
     else if (ev->code == ABS_Y)
         pEvdev->abs |= ABS_Y_VALUE;
+    else if (ev->code == ABS_MT_POSITION_X)
+        pEvdev->abs |= ABS_MT_X_VALUE;
+    else if (ev->code == ABS_MT_POSITION_Y)
+        pEvdev->abs |= ABS_MT_Y_VALUE;
     else
         pEvdev->abs |= ABS_VALUE;
 }
@@ -715,6 +722,8 @@ EvdevProcessEvent(InputInfoPtr pInfo, struct input_event *ev)
 #undef ABS_X_VALUE
 #undef ABS_Y_VALUE
 #undef ABS_VALUE
+#undef ABS_MT_X_VALUE
+#undef ABS_MT_Y_VALUE
 
 /* just a magic number to reduce the number of reads */
 #define NUM_EVENTS 16
@@ -1502,7 +1511,7 @@ EvdevInit(DeviceIntPtr device)
 
     if (pEvdev->flags & (EVDEV_UNIGNORE_RELATIVE | EVDEV_UNIGNORE_ABSOLUTE))
         EvdevInitAnyClass(device, pEvdev);
-    else if (pEvdev->flags & (EVDEV_TOUCHPAD | EVDEV_TOUCHSCREEN | EVDEV_TABLET))
+    else if (pEvdev->flags & (EVDEV_TOUCHPAD | EVDEV_TOUCHSCREEN | EVDEV_TABLET | EVDEV_MULTITOUCH))
         EvdevInitTouchDevice(device, pEvdev);
     else if (pEvdev->flags & EVDEV_RELATIVE_EVENTS)
         EvdevInitRelClass(device, pEvdev);
@@ -1881,6 +1890,15 @@ EvdevProbe(InputInfoPtr pInfo)
         xf86Msg(X_INFO, "%s: Found absolute axes\n", pInfo->name);
         pEvdev->flags |= EVDEV_ABSOLUTE_EVENTS;
 
+        if ((TestBit(ABS_MT_POSITION_X, pEvdev->abs_bitmask) &&
+                        TestBit(ABS_MT_POSITION_Y, pEvdev->abs_bitmask))) {
+            xf86Msg(X_INFO, "%s: Found absolute multitouch tablet.\n", pInfo->name);
+            pEvdev->flags |= EVDEV_MULTITOUCH;
+            if (!pEvdev->num_buttons) {
+                pEvdev->num_buttons = 7; /* LMR + scroll wheels */
+                pEvdev->flags |= EVDEV_BUTTON_EVENTS;
+            }
+        }
         if ((TestBit(ABS_X, pEvdev->abs_bitmask) &&
              TestBit(ABS_Y, pEvdev->abs_bitmask))) {
             xf86Msg(X_INFO, "%s: Found x and y absolute axes\n", pInfo->name);
@@ -1929,6 +1947,9 @@ EvdevProbe(InputInfoPtr pInfo)
         } else if (pEvdev->flags & EVDEV_TOUCHSCREEN) {
             xf86Msg(X_INFO, "%s: Configuring as touchscreen\n", pInfo->name);
             pInfo->type_name = XI_TOUCHSCREEN;
+        } else if (pEvdev->flags & EVDEV_MULTITOUCH) {
+            xf86Msg(X_INFO, "%s: Configuring as multitouch screen\n", pInfo->name);
+            pInfo->type_name = "MULTITOUCHSCREEN";
 	} else {
 	    xf86Msg(X_INFO, "%s: Configuring as mouse\n", pInfo->name);
 	    pInfo->type_name = XI_MOUSE;
@@ -2493,6 +2514,19 @@ EvdevInitProperty(DeviceIntPtr dev)
 
         XISetDevicePropertyDeletable(dev, prop_swap, FALSE);
 
+        if (pEvdev->flags & EVDEV_MULTITOUCH) {
+            /* The number of multitouch subdevices.
+             * If 0, we emulate a touchscreen. */
+            prop_multitouch = MakeAtom(EVDEV_PROP_MULTITOUCH_SUBDEVICES,
+                    strlen(EVDEV_PROP_MULTITOUCH_SUBDEVICES), TRUE);
+            rc = XIChangeDeviceProperty(dev, prop_multitouch, XA_INTEGER, 8,
+                    PropModeReplace, 1, &pEvdev->num_multitouch, FALSE);
+            if (rc != Success)
+                return;
+
+            XISetDevicePropertyDeletable(dev, prop_multitouch, FALSE);
+        }
+
 #ifdef HAVE_LABELS
         /* Axis labelling */
         if ((pEvdev->num_vals > 0) && (prop_axis_label = XIGetKnownProperty(AXIS_LABEL_PROP)))
diff --git a/src/evdev.h b/src/evdev.h
index 1133985..f78420b 100644
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -70,6 +70,7 @@
 #define EVDEV_UNIGNORE_ABSOLUTE (1 << 9) /* explicitly unignore abs axes */
 #define EVDEV_UNIGNORE_RELATIVE (1 << 10) /* explicitly unignore rel axes */
 #define EVDEV_RELATIVE_MODE	(1 << 11) /* Force relative events for devices with absolute axes */
+#define EVDEV_MULTITOUCH	(1 << 12) /* device looks like a multi-touch screen? */
 
 #if GET_ABI_MAJOR(ABI_XINPUT_VERSION) >= 3
 #define HAVE_PROPERTIES 1
@@ -79,6 +80,8 @@
 #define MAX_VALUATORS 36
 #endif
 
+/* MT related */
+#define EVDEV_PROP_MULTITOUCH_SUBDEVICES "Evdev MultiTouch"
 
 #if GET_ABI_MAJOR(ABI_XINPUT_VERSION) < 5
 typedef struct {
@@ -192,6 +195,9 @@ typedef struct {
     /* Event queue used to defer keyboard/button events until EV_SYN time. */
     int                     num_queue;
     EventQueueRec           queue[EVDEV_MAXQUEUE];
+
+    /* mt-related */
+    unsigned int num_multitouch;
 } EvdevRec, *EvdevPtr;
 
 /* Event posting functions */