add ttyprintk driver

Ttyprintk is a pseudo TTY driver, which allows users to make printk
messages, via output to ttyprintk device. It is possible to store
"console" messages inline with kernel messages for better analyses of
the boot process, for example.

Signed-off-by: Samo Pogacnik <samo_pogacnik@t-2.net>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/Documentation/devices.txt b/Documentation/devices.txt
index d0d1df6cb5de..6a08fd731d28 100644
--- a/Documentation/devices.txt
+++ b/Documentation/devices.txt
@@ -239,6 +239,7 @@ Your cooperation is appreciated.
                   0 = /dev/tty          Current TTY device
                   1 = /dev/console      System console
                   2 = /dev/ptmx         PTY master multiplex
+                  3 = /dev/ttyprintk    User messages via printk TTY device
                  64 = /dev/cua0         Callout device for ttyS0
                     ...
                 255 = /dev/cua191       Callout device for ttyS191