[PATCH] fix jumpy mouse cursor on console

Do not send empty events to gpm.  (Keyboards are assumed to have scroll
wheel these days, that makes them part-mouse.  That means typing on
keyboard generates empty mouse events).

From: Dmitry Torokhov <dtor_core@ameritech.net>
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/input/mousedev.c b/drivers/input/mousedev.c
index 564974ce5793..96fb9870834a 100644
--- a/drivers/input/mousedev.c
+++ b/drivers/input/mousedev.c
@@ -101,6 +101,7 @@ struct mousedev_list {
         unsigned char ready, buffer, bufsiz;
         unsigned char imexseq, impsseq;
         enum mousedev_emul mode;
+        unsigned long last_buttons;
 };
 
 #define MOUSEDEV_SEQ_LEN        6
@@ -224,7 +225,7 @@ static void mousedev_notify_readers(struct mousedev *mousedev, struct mousedev_h
                 spin_lock_irqsave(&list->packet_lock, flags);
 
                 p = &list->packets[list->head];
-                if (list->ready && p->buttons != packet->buttons) {
+                if (list->ready && p->buttons != mousedev->packet.buttons) {
                         unsigned int new_head = (list->head + 1) % PACKET_QUEUE_LEN;
                         if (new_head != list->tail) {
                                 p = &list->packets[list->head = new_head];
@@ -249,10 +250,13 @@ static void mousedev_notify_readers(struct mousedev *mousedev, struct mousedev_h
                 p->dz += packet->dz;
                 p->buttons = mousedev->packet.buttons;
 
-                list->ready = 1;
+                if (p->dx || p->dy || p->dz || p->buttons != list->last_buttons)
+                        list->ready = 1;
 
                 spin_unlock_irqrestore(&list->packet_lock, flags);
-                kill_fasync(&list->fasync, SIGIO, POLL_IN);
+
+                if (list->ready)
+                        kill_fasync(&list->fasync, SIGIO, POLL_IN);
         }
 
         wake_up_interruptible(&mousedev->wait);
@@ -477,9 +481,10 @@ static void mousedev_packet(struct mousedev_list *list, signed char *ps2_data)
         }
 
         if (!p->dx && !p->dy && !p->dz) {
-                if (list->tail == list->head)
+                if (list->tail == list->head) {
                         list->ready = 0;
-                else
+                        list->last_buttons = p->buttons;
+                } else
                         list->tail = (list->tail + 1) % PACKET_QUEUE_LEN;
         }