Input: ucb1400_ts - allow passing IRQ through platfrom_data

This patch allows UCB1400 to get IRQ GPIO from platform data. In case
platform_data are not supplied or the IRQ supplied in the platform_data
is negative, fall back to the old IRQ detection algorithm.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/ucb1400_ts.c b/drivers/input/touchscreen/ucb1400_ts.c
index 095f84b..89dcbe7 100644
--- a/drivers/input/touchscreen/ucb1400_ts.c
+++ b/drivers/input/touchscreen/ucb1400_ts.c
@@ -355,10 +355,13 @@
 		goto err;
 	}
 
-	error = ucb1400_ts_detect_irq(ucb);
-	if (error) {
-		printk(KERN_ERR "UCB1400: IRQ probe failed\n");
-		goto err_free_devs;
+	/* Only in case the IRQ line wasn't supplied, try detecting it */
+	if (ucb->irq < 0) {
+		error = ucb1400_ts_detect_irq(ucb);
+		if (error) {
+			printk(KERN_ERR "UCB1400: IRQ probe failed\n");
+			goto err_free_devs;
+		}
 	}
 
 	init_waitqueue_head(&ucb->ts_wait);