[media] media: au0828 set ctrl_input in au0828_s_input()

dev->ctrl_input is set in vidioc_s_input() and doesn't get set in
au0828_s_input(). As a result, dev->ctrl_input is left uninitialized
until user space calls s_input.

It works correctly because the default input value is 0 and which is
what dev->ctrl_input gets initialized via kzalloc().

Change to set dev->ctrl_input in au0828_s_input(). Also optimize
vidioc_s_input() to return if the new input value is same as the
current.

Signed-off-by: Shuah Khan <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/usb/au0828/au0828-video.c

···
 	default:
 		dprintk(1, "unknown input type set [%d]\n",
 			AUVI_INPUT(index).type);
-		break;
+		return;
 	}
+
+	dev->ctrl_input = index;
 
 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_routing,
 			AUVI_INPUT(index).vmux, 0, 0);
···
 		return -EINVAL;
 	if (AUVI_INPUT(index).type == 0)
 		return -EINVAL;
-	dev->ctrl_input = index;
+
+	if (dev->ctrl_input == index)
+		return 0;
+
 	au0828_s_input(dev, index);
 	return 0;
 }
···
 	dev->ctrl_ainput = 0;
 	dev->ctrl_freq = 960;
 	dev->std = V4L2_STD_NTSC_M;
+	/* Default input is TV Tuner */
 	au0828_s_input(dev, 0);
 
 	mutex_init(&dev->vb_queue_lock);