xen: make use of xenbus_read_unsigned() in xen-kbdfront

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: dmitry.torokhov@gmail.com
Cc: linux-input@vger.kernel.org

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

drivers/input/misc/xen-kbdfront.c

@@ -108,7 +108,8 @@ static irqreturn_t input_handler(int rq, void *dev_id)
 static int xenkbd_probe(struct xenbus_device *dev,
 				  const struct xenbus_device_id *id)
 {
-	int ret, i, abs;
+	int ret, i;
+	unsigned int abs;
 	struct xenkbd_info *info;
 	struct input_dev *kbd, *ptr;
 
@@ -127,8 +128,7 @@ static int xenkbd_probe(struct xenbus_device *dev,
 	if (!info->page)
 		goto error_nomem;
 
-	if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0)
+	abs = xenbus_read_unsigned(dev->otherend, "feature-abs-pointer", 0);
-		abs = 0;
 	if (abs) {
 		ret = xenbus_write(XBT_NIL, dev->nodename,
 				   "request-abs-pointer", "1");
@@ -322,11 +322,8 @@ static void xenkbd_backend_changed(struct xenbus_device *dev,
 
 	case XenbusStateInitWait:
 InitWait:
-		ret = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
+		if (xenbus_read_unsigned(info->xbdev->otherend,
-				   "feature-abs-pointer", "%d", &val);
+					 "feature-abs-pointer", 0)) {
-		if (ret < 0)
-			val = 0;
-		if (val) {
 			ret = xenbus_write(XBT_NIL, info->xbdev->nodename,
 					   "request-abs-pointer", "1");
 			if (ret)