um: switch line.c tty drivers to dynamic device creation

Current code doesn't update the symlinks in /sys/dev/char when we add/remove
tty lines.  Fixing that allows to stop messing with ->valid before the driver
registration, which is a Good Thing(tm) - we shouldn't have it set before we
really have the things set up and ready for line_open().

We need tty_driver available to call tty_{un,}register_device(), so we just
stash a reference to it into struct line_driver.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 6 insertions, 11 deletions

diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c
index 23cffd6d85af..6398a47d035b 100644
--- a/arch/um/drivers/ssl.c
+++ b/arch/um/drivers/ssl.c
@@ -20,12 +20,6 @@
 
 static const int ssl_version = 1;
 
-/* Referenced only by tty_driver below - presumably it's locked correctly
- * by the tty driver.
- */
-
-static struct tty_driver *ssl_driver;
-
 #define NR_PORTS 64
 
 static void ssl_announce(char *dev_name, int dev)
@@ -164,7 +158,7 @@ static void ssl_console_write(struct console *c, const char *string,
 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 {
         *index = c->index;
-        return ssl_driver;
+        return driver.driver;
 }
 
 static int ssl_console_setup(struct console *co, char *options)
@@ -187,6 +181,7 @@ static struct console ssl_cons = {
 static int ssl_init(void)
 {
         char *new_title;
+        int err;
         int i;
 
         printk(KERN_INFO "Initializing software serial port version %d\n",
@@ -196,16 +191,16 @@ static int ssl_init(void)
                 char *s = conf[i];
                 if (!s)
                         s = def_conf;
-                if (s && strcmp(s, "none") != 0) {
+                if (s && strcmp(s, "none") != 0)
                         serial_lines[i].init_str = s;
-                        serial_lines[i].valid = 1;
-                }
                 spin_lock_init(&serial_lines[i].lock);
                 mutex_init(&serial_lines[i].count_lock);
                 serial_lines[i].driver = &driver;
         }
-        ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
+        err = register_lines(&driver, &ssl_ops, serial_lines,
                                     ARRAY_SIZE(serial_lines));
+        if (err)
+                return err;
 
         new_title = add_xterm_umid(opts.xterm_title);
         if (new_title != NULL)