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>

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/input/xen-kbdfront.c b/drivers/input/xen-kbdfront.c
index 0f47f4697cdf..9da4452786fa 100644
--- a/drivers/input/xen-kbdfront.c
+++ b/drivers/input/xen-kbdfront.c
@@ -66,6 +66,9 @@ static irqreturn_t input_handler(int rq, void *dev_id)
                 case XENKBD_TYPE_MOTION:
                         input_report_rel(dev, REL_X, event->motion.rel_x);
                         input_report_rel(dev, REL_Y, event->motion.rel_y);
+                        if (event->motion.rel_z)
+                                input_report_rel(dev, REL_WHEEL,
+                                                 -event->motion.rel_z);
                         break;
                 case XENKBD_TYPE_KEY:
                         dev = NULL;
@@ -84,6 +87,9 @@ static irqreturn_t input_handler(int rq, void *dev_id)
                 case XENKBD_TYPE_POS:
                         input_report_abs(dev, ABS_X, event->pos.abs_x);
                         input_report_abs(dev, ABS_Y, event->pos.abs_y);
+                        if (event->pos.rel_z)
+                                input_report_rel(dev, REL_WHEEL,
+                                                 -event->pos.rel_z);
                         break;
                 }
                 if (dev)
@@ -152,7 +158,7 @@ static int __devinit xenkbd_probe(struct xenbus_device *dev,
         ptr->evbit[0] = BIT(EV_KEY) | BIT(EV_REL) | BIT(EV_ABS);
         for (i = BTN_LEFT; i <= BTN_TASK; i++)
                 set_bit(i, ptr->keybit);
-        ptr->relbit[0] = BIT(REL_X) | BIT(REL_Y);
+        ptr->relbit[0] = BIT(REL_X) | BIT(REL_Y) | BIT(REL_WHEEL);
         input_set_abs_params(ptr, ABS_X, 0, XENFB_WIDTH, 0, 0);
         input_set_abs_params(ptr, ABS_Y, 0, XENFB_HEIGHT, 0, 0);
 
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