USB: dummy-hcd: use dynamic allocation for platform_devices

This patch (as1075) changes dummy-hcd to dynamically allocate its
platform_device structures, using the core platform_device_alloc()
interface.  This is what it should have done all along, because the
dynamically-allocated structures have a release method in the driver
core and are therefore immune to being released after the module has
been unloaded.

Thanks to Richard Purdie for pointing out the need for this change.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/dummy_hcd.c

@@ -1933,69 +1933,57 @@ static struct platform_driver dummy_hcd_driver = {
 
 /*-------------------------------------------------------------------------*/
 
-/* These don't need to do anything because the pdev structures are
- * statically allocated. */
-static void
-dummy_udc_release (struct device *dev) {}
-
-static void
-dummy_hcd_release (struct device *dev) {}
-
-static struct platform_device		the_udc_pdev = {
-	.name		= (char *) gadget_name,
-	.id		= -1,
-	.dev		= {
-		.release	= dummy_udc_release,
-	},
-};
-
-static struct platform_device		the_hcd_pdev = {
-	.name		= (char *) driver_name,
-	.id		= -1,
-	.dev		= {
-		.release	= dummy_hcd_release,
-	},
-};
+static struct platform_device *the_udc_pdev;
+static struct platform_device *the_hcd_pdev;
 
 static int __init init (void)
 {
-	int	retval;
+	int	retval = -ENOMEM;
 
 	if (usb_disabled ())
 		return -ENODEV;
 
-	retval = platform_driver_register (&dummy_hcd_driver);
-	if (retval < 0)
+	the_hcd_pdev = platform_device_alloc(driver_name, -1);
+	if (!the_hcd_pdev)
 		return retval;
+	the_udc_pdev = platform_device_alloc(gadget_name, -1);
+	if (!the_udc_pdev)
+		goto err_alloc_udc;
 
-	retval = platform_driver_register (&dummy_udc_driver);
+	retval = platform_driver_register(&dummy_hcd_driver);
+	if (retval < 0)
+		goto err_register_hcd_driver;
+	retval = platform_driver_register(&dummy_udc_driver);
 	if (retval < 0)
 		goto err_register_udc_driver;
 
-	retval = platform_device_register (&the_hcd_pdev);
+	retval = platform_device_add(the_hcd_pdev);
 	if (retval < 0)
-		goto err_register_hcd;
-
-	retval = platform_device_register (&the_udc_pdev);
+		goto err_add_hcd;
+	retval = platform_device_add(the_udc_pdev);
 	if (retval < 0)
-		goto err_register_udc;
+		goto err_add_udc;
 	return retval;
 
-err_register_udc:
-	platform_device_unregister (&the_hcd_pdev);
-err_register_hcd:
-	platform_driver_unregister (&dummy_udc_driver);
+err_add_udc:
+	platform_device_del(the_hcd_pdev);
+err_add_hcd:
+	platform_driver_unregister(&dummy_udc_driver);
 err_register_udc_driver:
-	platform_driver_unregister (&dummy_hcd_driver);
+	platform_driver_unregister(&dummy_hcd_driver);
+err_register_hcd_driver:
+	platform_device_put(the_udc_pdev);
+err_alloc_udc:
+	platform_device_put(the_hcd_pdev);
 	return retval;
 }
 module_init (init);
 
 static void __exit cleanup (void)
 {
-	platform_device_unregister (&the_udc_pdev);
-	platform_device_unregister (&the_hcd_pdev);
-	platform_driver_unregister (&dummy_udc_driver);
-	platform_driver_unregister (&dummy_hcd_driver);
+	platform_device_unregister(the_udc_pdev);
+	platform_device_unregister(the_hcd_pdev);
+	platform_driver_unregister(&dummy_udc_driver);
+	platform_driver_unregister(&dummy_hcd_driver);
 }
 module_exit (cleanup);