[PATCH] Char: istallion, change init sequence

Reorganizate module init and exit and implement logic, when something fails in
these functions.  The former is needed for proper handling dynamic
tty_register_device.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 75 insertions, 55 deletions

diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
index 0f287f1b4342..a1755186f7b4 100644
--- a/drivers/char/istallion.c
+++ b/drivers/char/istallion.c
@@ -4545,46 +4545,49 @@ static const struct tty_operations stli_ops = {
  *      Loadable module initialization stuff.
  */
 
+static void istallion_cleanup_isa(void)
+{
+        struct stlibrd  *brdp;
+        unsigned int j;
+
+        for (j = 0; (j < stli_nrbrds); j++) {
+                if ((brdp = stli_brds[j]) == NULL || (brdp->state & BST_PROBED))
+                        continue;
+
+                stli_cleanup_ports(brdp);
+
+                iounmap(brdp->membase);
+                if (brdp->iosize > 0)
+                        release_region(brdp->iobase, brdp->iosize);
+                kfree(brdp);
+                stli_brds[j] = NULL;
+        }
+}
+
 static int __init istallion_module_init(void)
 {
-        int i;
+        unsigned int i;
+        int retval;
 
         printk(KERN_INFO "%s: version %s\n", stli_drvtitle, stli_drvversion);
 
         spin_lock_init(&stli_lock);
         spin_lock_init(&brd_lock);
 
-        stli_initbrds();
-
-        stli_serial = alloc_tty_driver(STL_MAXBRDS * STL_MAXPORTS);
-        if (!stli_serial)
-                return -ENOMEM;
-
-/*
- *      Allocate a temporary write buffer.
- */
         stli_txcookbuf = kmalloc(STLI_TXBUFSIZE, GFP_KERNEL);
-        if (!stli_txcookbuf)
+        if (!stli_txcookbuf) {
                 printk(KERN_ERR "STALLION: failed to allocate memory "
                                 "(size=%d)\n", STLI_TXBUFSIZE);
+                retval = -ENOMEM;
+                goto err;
+        }
 
-/*
- *      Set up a character driver for the shared memory region. We need this
- *      to down load the slave code image. Also it is a useful debugging tool.
- */
-        if (register_chrdev(STL_SIOMEMMAJOR, "staliomem", &stli_fsiomem))
-                printk(KERN_ERR "STALLION: failed to register serial memory "
-                                "device\n");
-
-        istallion_class = class_create(THIS_MODULE, "staliomem");
-        for (i = 0; i < 4; i++)
-                class_device_create(istallion_class, NULL,
-                                MKDEV(STL_SIOMEMMAJOR, i),
-                                NULL, "staliomem%d", i);
+        stli_serial = alloc_tty_driver(STL_MAXBRDS * STL_MAXPORTS);
+        if (!stli_serial) {
+                retval = -ENOMEM;
+                goto err_free;
+        }
 
-/*
- *      Set up the tty driver structure and register us as a driver.
- */
         stli_serial->owner = THIS_MODULE;
         stli_serial->driver_name = stli_drvname;
         stli_serial->name = stli_serialname;
@@ -4596,58 +4599,75 @@ static int __init istallion_module_init(void)
         stli_serial->flags = TTY_DRIVER_REAL_RAW;
         tty_set_operations(stli_serial, &stli_ops);
 
-        if (tty_register_driver(stli_serial)) {
-                put_tty_driver(stli_serial);
+        retval = tty_register_driver(stli_serial);
+        if (retval) {
                 printk(KERN_ERR "STALLION: failed to register serial driver\n");
-                return -EBUSY;
+                goto err_ttyput;
+        }
+
+        retval = stli_initbrds();
+        if (retval)
+                goto err_ttyunr;
+
+/*
+ *      Set up a character driver for the shared memory region. We need this
+ *      to down load the slave code image. Also it is a useful debugging tool.
+ */
+        retval = register_chrdev(STL_SIOMEMMAJOR, "staliomem", &stli_fsiomem);
+        if (retval) {
+                printk(KERN_ERR "STALLION: failed to register serial memory "
+                                "device\n");
+                goto err_deinit;
         }
+
+        istallion_class = class_create(THIS_MODULE, "staliomem");
+        for (i = 0; i < 4; i++)
+                class_device_create(istallion_class, NULL,
+                                MKDEV(STL_SIOMEMMAJOR, i),
+                                NULL, "staliomem%d", i);
+
         return 0;
+err_deinit:
+        pci_unregister_driver(&stli_pcidriver);
+        istallion_cleanup_isa();
+err_ttyunr:
+        tty_unregister_driver(stli_serial);
+err_ttyput:
+        put_tty_driver(stli_serial);
+err_free:
+        kfree(stli_txcookbuf);
+err:
+        return retval;
 }
 
 /*****************************************************************************/
 
 static void __exit istallion_module_exit(void)
 {
-        struct stlibrd  *brdp;
         unsigned int j;
-        int             i;
 
         printk(KERN_INFO "Unloading %s: version %s\n", stli_drvtitle,
                 stli_drvversion);
 
-        pci_unregister_driver(&stli_pcidriver);
-        /*
-         *      Free up all allocated resources used by the ports. This includes
-         *      memory and interrupts.
-         */
         if (stli_timeron) {
                 stli_timeron = 0;
                 del_timer_sync(&stli_timerlist);
         }
 
-        i = tty_unregister_driver(stli_serial);
-        put_tty_driver(stli_serial);
+        unregister_chrdev(STL_SIOMEMMAJOR, "staliomem");
+
         for (j = 0; j < 4; j++)
-                class_device_destroy(istallion_class, MKDEV(STL_SIOMEMMAJOR, j));
+                class_device_destroy(istallion_class, MKDEV(STL_SIOMEMMAJOR,
+                                        j));
         class_destroy(istallion_class);
-        if ((i = unregister_chrdev(STL_SIOMEMMAJOR, "staliomem")))
-                printk("STALLION: failed to un-register serial memory device, "
-                        "errno=%d\n", -i);
-
-        kfree(stli_txcookbuf);
 
-        for (j = 0; (j < stli_nrbrds); j++) {
-                if ((brdp = stli_brds[j]) == NULL || (brdp->state & BST_PROBED))
-                        continue;
+        pci_unregister_driver(&stli_pcidriver);
+        istallion_cleanup_isa();
 
-                stli_cleanup_ports(brdp);
+        tty_unregister_driver(stli_serial);
+        put_tty_driver(stli_serial);
 
-                iounmap(brdp->membase);
-                if (brdp->iosize > 0)
-                        release_region(brdp->iobase, brdp->iosize);
-                kfree(brdp);
-                stli_brds[j] = NULL;
-        }
+        kfree(stli_txcookbuf);
 }
 
 module_init(istallion_module_init);