[media] lirc: wire up .compat_ioctl to main ioctl handler

As pointed out (and tested) by Joris van Rantwijk, we do actually need
to wire up .compat_ioctl for 32-bit lirc userspace to work with 64-bit
lirc kernelspace. Do it. And add a check to make sure we get a valid
irctl in the ioctl handler.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/IR/lirc_dev.c b/drivers/media/IR/lirc_dev.c
index e4e4d99..c20cfd1 100644
--- a/drivers/media/IR/lirc_dev.c
+++ b/drivers/media/IR/lirc_dev.c
@@ -161,6 +161,9 @@
 	.write		= lirc_dev_fop_write,
 	.poll		= lirc_dev_fop_poll,
 	.unlocked_ioctl	= lirc_dev_fop_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= lirc_dev_fop_ioctl,
+#endif
 	.open		= lirc_dev_fop_open,
 	.release	= lirc_dev_fop_close,
 };
@@ -528,6 +531,11 @@
 	int result = 0;
 	struct irctl *ir = file->private_data;
 
+	if (!ir) {
+		printk(KERN_ERR "lirc_dev: %s: no irctl found!\n", __func__);
+		return -ENODEV;
+	}
+
 	dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
 		ir->d.name, ir->d.minor, cmd);