diff --git a/drivers/input/mouse/pxa930_trkball.c b/drivers/input/mouse/pxa930_trkball.c
index a0f45c4fc198..784be69b7112 100644
--- a/drivers/input/mouse/pxa930_trkball.c
+++ b/drivers/input/mouse/pxa930_trkball.c
@@ -83,7 +83,7 @@ static int write_tbcr(struct pxa930_trkball *trkball, int v)
 
 	__raw_writel(v, trkball->mmio_base + TBCR);
 
-	while (i--) {
+	while (--i) {
 		if (__raw_readl(trkball->mmio_base + TBCR) == v)
 			break;
 		msleep(1);