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hw/input/ps2.c: fix erratic mouse behavior for Windows 3.1

PATCH In review John Arbuckle 2 participants 3 messages Aug 19, 2018 – Aug 20, 2018

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John Arbuckle

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#0 lore raw

PATCH 1/1 hw/input/ps2.c: fix erratic mouse behavior for Windows 3.1

When the user moves the mouse and moves the scroll wheel at the same time, the mouse cursor's movement becomes erratic in Windows 3.1. With this patch if the mouse is in ps/2 mode and the scroll wheel is used, the command queue is reset. This does not fix the erratic mouse problem in Windows NT 4.0.

Signed-off-by John Arbuckle <[email protected]>
---
 hw/input/ps2.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)
hw/input/ps2.c +10 -1
index fdfcadf9a1..bb9ebfa5a9 100644
@@ -685,8 +685,17 @@ static int ps2_mouse_send_packet(PS2MouseState *s)
     /* update deltas */
     s->mouse_dx -= dx1;
     s->mouse_dy -= dy1;
-    s->mouse_dz -= dz1;
+    /*
+     * This prevents the mouse from going crazy in Windows that doesn't support
+     * the Microsoft Intellimouse standard.
+     */
+    if (s->mouse_type == 0 && s->mouse_dz != 0) {
+        s->mouse_dz = 0;
+        ps2_reset_queue(&s->common);
+        return 1;
+    }
 
+    s->mouse_dz -= dz1;
     return 1;
 }
Signature · 1 line
2.14.3 (Apple Git-98)
#1 lore raw
Quoted 5 lines · John Arbuckle

When the user moves the mouse and moves the scroll wheel at the same time, the mouse cursor's movement becomes erratic in Windows 3.1. With this patch if the mouse is in ps/2 mode and the scroll wheel is used, the command queue is reset. This does not fix the erratic mouse problem in Windows NT 4.0.

I don't think we need to reset the queue. Just ignoring the z axis value for type 0 should do. Can you try this?

hw/input/ps2.c +2 -0
@@ -661,6 +661,8 @@ static int ps2_mouse_send_packet(PS2MouseState *s)
     /* extra byte for IMPS/2 or IMEX */
     switch(s->mouse_type) {
     default:
+        s->mouse_dz = 0;
+        dz1 = 0;
         break;
     case 3:
         if (dz1 > 127)

cheers,
Gerd

author
#2 lore raw
Quoted 25 lines · Gerd Hoffmann
Quoted 5 lines · John Arbuckle

When the user moves the mouse and moves the scroll wheel at the same time, the mouse cursor's movement becomes erratic in Windows 3.1. With this patch if the mouse is in ps/2 mode and the scroll wheel is used, the command queue is reset. This does not fix the erratic mouse problem in Windows NT 4.0.

I don't think we need to reset the queue. Just ignoring the z axis value for type 0 should do. Can you try this?

hw/input/ps2.c +2 -0
@@ -661,6 +661,8 @@ static int ps2_mouse_send_packet(PS2MouseState *s)
    /* extra byte for IMPS/2 or IMEX */
    switch(s->mouse_type) {
    default:
+        s->mouse_dz = 0;
+        dz1 = 0;
        break;
    case 3:
        if (dz1 > 127)
Quoted 3 lines

cheers,
Gerd

Sorry it did not fix the problem.

https://winworldpc.com/product/windows-3/31
In case you or anyone else wishes to reproduce this problem, the link to the Windows 3.1 installer is above.

Thank you.