From 2d4fda4b09e67e47d3e6fc4743fc6e81bfe40f28 Mon Sep 17 00:00:00 2001
From: Marcin Slusarz <marcin.slusarz@gmail.com>
Date: Mon, 21 May 2012 21:39:43 +0200
Subject: [PATCH] xfree86: fix mouse wheel support for DGA clients

xf86-input-evdev (since "smooth scrolling" support was added) can send mouse
motion and wheel events in one batch, so we need to handle it properly.
Otherwise mouse wheel events which come with motion events are lost
and separate mouse wheel events are handled through non-DGA path.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
---
 hw/xfree86/common/xf86Xinput.c | 94 ++++++++++++++++++++++++++++------
 1 file changed, 78 insertions(+), 16 deletions(-)

diff --git a/hw/xfree86/common/xf86Xinput.c b/hw/xfree86/common/xf86Xinput.c
index 77b800000..bee407bf9 100644
--- a/hw/xfree86/common/xf86Xinput.c
+++ b/hw/xfree86/common/xf86Xinput.c
@@ -1059,26 +1059,24 @@ xf86PostMotionEventP(DeviceIntPtr device,
     xf86PostMotionEventM(device, is_absolute, &mask);
 }
 
-void
-xf86PostMotionEventM(DeviceIntPtr device,
-                     int is_absolute, const ValuatorMask *mask)
+static int
+xf86CheckMotionEvent4DGA(DeviceIntPtr device, int is_absolute,
+                         const ValuatorMask *mask)
 {
-    int flags = 0;
-
-    if (valuator_mask_num_valuators(mask) > 0) {
-        if (is_absolute)
-            flags = POINTER_ABSOLUTE;
-        else
-            flags = POINTER_RELATIVE | POINTER_ACCELERATE;
-    }
+    int stolen = 0;
 
 #if XFreeXDGA
+    ScreenPtr scr = NULL;
+    int idx, i;
+
     /* The evdev driver may not always send all axes across. */
-    if (valuator_mask_isset(mask, 0) || valuator_mask_isset(mask, 1))
-        if (miPointerGetScreen(device)) {
-            int index = miPointerGetScreen(device)->myNum;
+    if (valuator_mask_isset(mask, 0) || valuator_mask_isset(mask, 1)) {
+        scr = miPointerGetScreen(device);
+        if (scr) {
             int dx = 0, dy = 0;
 
+            idx = scr->myNum;
+
             if (valuator_mask_isset(mask, 0)) {
                 dx = valuator_mask_get(mask, 0);
                 if (is_absolute)
@@ -1091,11 +1089,75 @@ xf86PostMotionEventM(DeviceIntPtr device,
                     dy -= device->last.valuators[1];
             }
 
-            if (DGAStealMotionEvent(device, index, dx, dy))
-                return;
+            if (DGAStealMotionEvent(device, idx, dx, dy))
+                stolen = 1;
         }
+    }
+
+    for (i = 2; i < valuator_mask_size(mask); i++) {
+        AxisInfoPtr ax;
+        double incr;
+        int val, button;
+
+        if (i >= device->valuator->numAxes)
+            break;
+
+        if (!valuator_mask_isset(mask, i))
+            continue;
+
+        ax = &device->valuator->axes[i];
+
+        if (ax->scroll.type == SCROLL_TYPE_NONE)
+            continue;
+
+        if (!scr) {
+            scr = miPointerGetScreen(device);
+            if (!scr)
+                break;
+            idx = scr->myNum;
+        }
+
+        incr = ax->scroll.increment;
+        val = valuator_mask_get(mask, i);
+
+        if (ax->scroll.type == SCROLL_TYPE_VERTICAL) {
+            if (incr * val < 0)
+                button = 4; /* up */
+            else
+                button = 5; /* down */
+        } else { /* SCROLL_TYPE_HORIZONTAL */
+            if (incr * val < 0)
+                button = 6; /* left */
+            else
+                button = 7; /* right */
+        }
+
+        if (DGAStealButtonEvent(device, idx, button, 1) &&
+                DGAStealButtonEvent(device, idx, button, 0))
+            stolen = 1;
+    }
+
 #endif
 
+    return stolen;
+}
+
+void
+xf86PostMotionEventM(DeviceIntPtr device,
+                     int is_absolute, const ValuatorMask *mask)
+{
+    int flags = 0;
+
+    if (xf86CheckMotionEvent4DGA(device, is_absolute, mask))
+        return;
+
+    if (valuator_mask_num_valuators(mask) > 0) {
+        if (is_absolute)
+            flags = POINTER_ABSOLUTE;
+        else
+            flags = POINTER_RELATIVE | POINTER_ACCELERATE;
+    }
+
     QueuePointerEvents(device, MotionNotify, 0, flags, mask);
 }