[PATCH] tty: kgdb_nmi: Convert kgdb_nmi_tty_enabled into a module parameter

[Daniel Thompson <daniel.thompson@linaro.org>]

At present it is not possible to boot with the ttyNMI0 console treating
character input normally. To use the console requires that kdb be
entered and the nmi_console command be used to enable the console (or if
only kgdb is present then gdb must directly manipulate the value of
kgdb_nmi_tty_enabled).

Introducing a module parameter makes the console much more usable.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
---
 drivers/tty/serial/kgdb_nmi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c
index cfadf29..9361d69 100644
--- a/drivers/tty/serial/kgdb_nmi.c
+++ b/drivers/tty/serial/kgdb_nmi.c
@@ -43,6 +43,11 @@ module_param_named(magic, kgdb_nmi_magic, charp, 0600);
 MODULE_PARM_DESC(magic, "magic sequence to enter NMI debugger (default $3#33)");
 
 static bool kgdb_nmi_tty_enabled;
+module_param_named(tty, kgdb_nmi_tty_enabled, bool, 0600);
+MODULE_PARM_DESC(tty, "if set to false (default), characters received from "
+		      "the UART will be passed exclusively to the knock "
+		      "detector; when set to true characters will be passed "
+		      "both to the knock detector and to the TTY layer");
 
 static int kgdb_nmi_console_setup(struct console *co, char *options)
 {
-- 
1.9.3