[PATCH] tty_driver refcounting

drivers/char/pcmcia/synclink_cs.c converted to dynamic allocation

drivers/char/pcmcia/synclink_cs.c

@@ -495,7 +495,7 @@ MODULE_LICENSE("GPL");
 static char *driver_name = "SyncLink PC Card driver";
 static char *driver_version = "$Revision: 4.10 $";
 
-static struct tty_driver serial_driver;
+static struct tty_driver *serial_driver;
 
 /* number of characters left in xmit buffer before we ask for more */
 #define WAKEUP_CHARS 256
@@ -3115,6 +3115,30 @@ static struct pcmcia_driver mgslpc_driver = {
 	.detach		= mgslpc_detach,
 };
 
+static struct tty_operations mgslpc_ops = {
+	.open = mgslpc_open,
+	.close = mgslpc_close,
+	.write = mgslpc_write,
+	.put_char = mgslpc_put_char,
+	.flush_chars = mgslpc_flush_chars,
+	.write_room = mgslpc_write_room,
+	.chars_in_buffer = mgslpc_chars_in_buffer,
+	.flush_buffer = mgslpc_flush_buffer,
+	.ioctl = mgslpc_ioctl,
+	.throttle = mgslpc_throttle,
+	.unthrottle = mgslpc_unthrottle,
+	.send_xchar = mgslpc_send_xchar,
+	.break_ctl = mgslpc_break,
+	.wait_until_sent = mgslpc_wait_until_sent,
+	.read_proc = mgslpc_read_proc,
+	.set_termios = mgslpc_set_termios,
+	.stop = tx_pause,
+	.start = tx_release,
+	.hangup = mgslpc_hangup,
+	.tiocmget = tiocmget,
+	.tiocmset = tiocmset,
+};
+
 static int __init synclink_cs_init(void)
 {
     int error;
@@ -3126,56 +3150,38 @@ static int __init synclink_cs_init(void)
 
     printk("%s %s\n", driver_name, driver_version);
 
+    serial_driver = alloc_tty_driver(MAX_DEVICE_COUNT);
+    if (!serial_driver)
+	    return -ENOMEM;
+
     error = pcmcia_register_driver(&mgslpc_driver);
-    if (error)
+    if (error) {
+	    put_tty_driver(serial_driver);
 	    return error;
+    }
 
     /* Initialize the tty_driver structure */
 	
-    memset(&serial_driver, 0, sizeof(struct tty_driver));
-    serial_driver.magic = TTY_DRIVER_MAGIC;
-    serial_driver.owner = THIS_MODULE;
-    serial_driver.driver_name = "synclink_cs";
-    serial_driver.name = "ttySLP";
-    serial_driver.major = ttymajor;
-    serial_driver.minor_start = 64;
-    serial_driver.num = MAX_DEVICE_COUNT;
-    serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
-    serial_driver.subtype = SERIAL_TYPE_NORMAL;
-    serial_driver.init_termios = tty_std_termios;
-    serial_driver.init_termios.c_cflag =
+    serial_driver->owner = THIS_MODULE;
+    serial_driver->driver_name = "synclink_cs";
+    serial_driver->name = "ttySLP";
+    serial_driver->major = ttymajor;
+    serial_driver->minor_start = 64;
+    serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+    serial_driver->subtype = SERIAL_TYPE_NORMAL;
+    serial_driver->init_termios = tty_std_termios;
+    serial_driver->init_termios.c_cflag =
 	    B9600 | CS8 | CREAD | HUPCL | CLOCAL;
-    serial_driver.flags = TTY_DRIVER_REAL_RAW;
-
-    serial_driver.open = mgslpc_open;
-    serial_driver.close = mgslpc_close;
-    serial_driver.write = mgslpc_write;
-    serial_driver.put_char = mgslpc_put_char;
-    serial_driver.flush_chars = mgslpc_flush_chars;
-    serial_driver.write_room = mgslpc_write_room;
-    serial_driver.chars_in_buffer = mgslpc_chars_in_buffer;
-    serial_driver.flush_buffer = mgslpc_flush_buffer;
-    serial_driver.ioctl = mgslpc_ioctl;
-    serial_driver.throttle = mgslpc_throttle;
-    serial_driver.unthrottle = mgslpc_unthrottle;
-    serial_driver.send_xchar = mgslpc_send_xchar;
-    serial_driver.break_ctl = mgslpc_break;
-    serial_driver.wait_until_sent = mgslpc_wait_until_sent;
-    serial_driver.read_proc = mgslpc_read_proc;
-    serial_driver.set_termios = mgslpc_set_termios;
-    serial_driver.stop = tx_pause;
-    serial_driver.start = tx_release;
-    serial_driver.hangup = mgslpc_hangup;
-    serial_driver.tiocmget = tiocmget;
-    serial_driver.tiocmset = tiocmset;
-	
-    if (tty_register_driver(&serial_driver) < 0)
+    serial_driver->flags = TTY_DRIVER_REAL_RAW;
+    tty_set_operations(serial_driver, &mgslpc_ops);
+
+    if (tty_register_driver(serial_driver) < 0)
 	    printk("%s(%d):Couldn't register serial driver\n",
 		   __FILE__,__LINE__);
 			
     printk("%s %s, tty major#%d\n",
 	   driver_name, driver_version,
-	   serial_driver.major);
+	   serial_driver->major);
 	
     return 0;
 }
@@ -3189,9 +3195,10 @@ static void __exit synclink_cs_exit(void)
 	while(mgslpc_device_list)
 		mgslpc_remove_device(mgslpc_device_list);
 
-	if ((rc = tty_unregister_driver(&serial_driver)))
+	if ((rc = tty_unregister_driver(serial_driver)))
 		printk("%s(%d) failed to unregister tty driver err=%d\n",
 		       __FILE__,__LINE__,rc);
+	put_tty_driver(serial_driver);
 
 	pcmcia_unregister_driver(&mgslpc_driver);