ttyprintk: Allow built as a module

The driver is well written to be used as a module, just the exit call
is missing.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 13 insertions, 2 deletions

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index fbae63e3d304..6e9f74a5c095 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -40,7 +40,7 @@ config SGI_MBCS
 source "drivers/tty/serial/Kconfig"
 
 config TTY_PRINTK
-        bool "TTY driver to output user messages via printk"
+        tristate "TTY driver to output user messages via printk"
         depends on EXPERT && TTY
         default n
         ---help---
diff --git a/drivers/char/ttyprintk.c b/drivers/char/ttyprintk.c
index 2a39c5790364..a15ce4ef39cd 100644
--- a/drivers/char/ttyprintk.c
+++ b/drivers/char/ttyprintk.c
@@ -17,7 +17,7 @@
 #include <linux/device.h>
 #include <linux/serial.h>
 #include <linux/tty.h>
-#include <linux/export.h>
+#include <linux/module.h>
 
 struct ttyprintk_port {
         struct tty_port port;
@@ -214,4 +214,15 @@ error:
         tty_port_destroy(&tpk_port.port);
         return ret;
 }
+
+static void __exit ttyprintk_exit(void)
+{
+        tty_unregister_driver(ttyprintk_driver);
+        put_tty_driver(ttyprintk_driver);
+        tty_port_destroy(&tpk_port.port);
+}
+
 device_initcall(ttyprintk_init);
+module_exit(ttyprintk_exit);
+
+MODULE_LICENSE("GPL");