Input: ct82710c - return proper error code for ct82c710_open

If request_irq() fails we should return the proper error instead of -1.

Signed-off-by: Davidlohr Bueso <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/serio/ct82c710.c

···
 static int ct82c710_open(struct serio *serio)
 {
 	unsigned char status;
+	int err;
 
-	if (request_irq(CT82C710_IRQ, ct82c710_interrupt, 0, "ct82c710", NULL))
-		return -1;
+	err = request_irq(CT82C710_IRQ, ct82c710_interrupt, 0, "ct82c710", NULL);
+	if (err)
+		return err;
 
 	status = inb_p(CT82C710_STATUS);
 
···
 		status &= ~(CT82C710_ENABLE | CT82C710_INTS_ON);
 		outb_p(status, CT82C710_STATUS);
 		free_irq(CT82C710_IRQ, NULL);
-		return -1;
+		return -EBUSY;
 	}
 
 	return 0;