xen pvfb: Pointer z-axis (mouse wheel) support

Add z-axis motion to pointer events.  Backward compatible, because
there's space for the z-axis in union xenkbd_in_event, and old
backends zero it.

Derived from
http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/57dfe0098000
http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/1edfea26a2a9
http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/c3ff0b26f664

Signed-off-by: Pat Campbell <plc@novell.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/xen/interface/io/kbdif.h b/include/xen/interface/io/kbdif.h
index fb97f4284ffd..8066c7849fbe 100644
--- a/include/xen/interface/io/kbdif.h
+++ b/include/xen/interface/io/kbdif.h
@@ -49,6 +49,7 @@ struct xenkbd_motion {
         uint8_t type;           /* XENKBD_TYPE_MOTION */
         int32_t rel_x;          /* relative X motion */
         int32_t rel_y;          /* relative Y motion */
+        int32_t rel_z;          /* relative Z motion (wheel) */
 };
 
 struct xenkbd_key {
@@ -61,6 +62,7 @@ struct xenkbd_position {
         uint8_t type;           /* XENKBD_TYPE_POS */
         int32_t abs_x;          /* absolute X position (in FB pixels) */
         int32_t abs_y;          /* absolute Y position (in FB pixels) */
+        int32_t rel_z;          /* relative Z motion (wheel) */
 };
 
 #define XENKBD_IN_EVENT_SIZE 40