Merge tag 'vfio-v5.11-rc1' of git://github.com/awilliam/linux-vfio

[linux-2.6-microblaze.git] / drivers / tty / ttynull.c

diff --git a/drivers/tty/ttynull.c b/drivers/tty/ttynull.c
index 17f05b7..eced70e 100644 (file)
--- a/drivers/tty/ttynull.c
+++ b/drivers/tty/ttynull.c
@@ -2,6 +2,13 @@
 /*
  * Copyright (C) 2019 Axis Communications AB
  *
+ * The console is useful for userspace applications which expect a console
+ * device to work without modifications even when no console is available
+ * or desired.
+ *
+ * In order to use this driver, you should redirect the console to this
+ * TTY, or boot the kernel with console=ttynull.
+ *
  * Based on ttyprintk.c:
  *  Copyright (C) 2010 Samo Pogacnik
  */
@@ -59,6 +66,17 @@ static struct console ttynull_console = {
        .device = ttynull_device,
 };
 
+void __init register_ttynull_console(void)
+{
+       if (!ttynull_driver)
+               return;
+
+       if (add_preferred_console(ttynull_console.name, 0, NULL))
+               return;
+
+       register_console(&ttynull_console);
+}
+
 static int __init ttynull_init(void)
 {
        struct tty_driver *driver;