mailbox: omap: Remove device class

The driver currently creates a new device class "mbox". Then for each
mailbox adds a device to that class. This class provides no file
operations provided for any userspace users of this device class.
It may have been extended to be functional in our vendor tree at
some point, but that is not the case anymore, nor does it matter
for the upstream tree.

Remove this device class and related functions and variables.
This also allows us to switch to module_platform_driver() as
there is nothing left to do in module_init().

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>

Author: glneo

drivers/mailbox/omap-mailbox.c

@@ -87,7 +87,6 @@ struct omap_mbox_device {
 	u32 intr_type;
 	struct omap_mbox **mboxes;
 	struct mbox_controller controller;
-	struct list_head elem;
 };
 
 struct omap_mbox_fifo_info {
@@ -107,7 +106,6 @@ struct omap_mbox {
 	const char		*name;
 	int			irq;
 	struct omap_mbox_queue	*rxq;
-	struct device		*dev;
 	struct omap_mbox_device *parent;
 	struct omap_mbox_fifo	tx_fifo;
 	struct omap_mbox_fifo	rx_fifo;
@@ -116,10 +114,6 @@ struct omap_mbox {
 	bool			send_no_irq;
 };
 
-/* global variables for the mailbox devices */
-static DEFINE_MUTEX(omap_mbox_devices_lock);
-static LIST_HEAD(omap_mbox_devices);
-
 static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
 module_param(mbox_kfifo_size, uint, S_IRUGO);
 MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
@@ -395,61 +389,6 @@ static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
 	return mbox;
 }
 
-static struct class omap_mbox_class = { .name = "mbox", };
-
-static int omap_mbox_register(struct omap_mbox_device *mdev)
-{
-	int ret;
-	int i;
-	struct omap_mbox **mboxes;
-
-	if (!mdev || !mdev->mboxes)
-		return -EINVAL;
-
-	mboxes = mdev->mboxes;
-	for (i = 0; mboxes[i]; i++) {
-		struct omap_mbox *mbox = mboxes[i];
-
-		mbox->dev = device_create(&omap_mbox_class, mdev->dev,
-					0, mbox, "%s", mbox->name);
-		if (IS_ERR(mbox->dev)) {
-			ret = PTR_ERR(mbox->dev);
-			goto err_out;
-		}
-	}
-
-	mutex_lock(&omap_mbox_devices_lock);
-	list_add(&mdev->elem, &omap_mbox_devices);
-	mutex_unlock(&omap_mbox_devices_lock);
-
-	ret = devm_mbox_controller_register(mdev->dev, &mdev->controller);
-
-err_out:
-	if (ret) {
-		while (i--)
-			device_unregister(mboxes[i]->dev);
-	}
-	return ret;
-}
-
-static int omap_mbox_unregister(struct omap_mbox_device *mdev)
-{
-	int i;
-	struct omap_mbox **mboxes;
-
-	if (!mdev || !mdev->mboxes)
-		return -EINVAL;
-
-	mutex_lock(&omap_mbox_devices_lock);
-	list_del(&mdev->elem);
-	mutex_unlock(&omap_mbox_devices_lock);
-
-	mboxes = mdev->mboxes;
-	for (i = 0; mboxes[i]; i++)
-		device_unregister(mboxes[i]->dev);
-	return 0;
-}
-
 static int omap_mbox_chan_startup(struct mbox_chan *chan)
 {
 	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
@@ -782,7 +721,7 @@ static int omap_mbox_probe(struct platform_device *pdev)
 	mdev->controller.chans = chnls;
 	mdev->controller.num_chans = info_count;
 	mdev->controller.of_xlate = omap_mbox_of_xlate;
-	ret = omap_mbox_register(mdev);
+	ret = devm_mbox_controller_register(mdev->dev, &mdev->controller);
 	if (ret)
 		return ret;
 
@@ -809,7 +748,6 @@ static int omap_mbox_probe(struct platform_device *pdev)
 
 unregister:
 	pm_runtime_disable(mdev->dev);
-	omap_mbox_unregister(mdev);
 	return ret;
 }
 
@@ -818,7 +756,6 @@ static void omap_mbox_remove(struct platform_device *pdev)
 	struct omap_mbox_device *mdev = platform_get_drvdata(pdev);
 
 	pm_runtime_disable(mdev->dev);
-	omap_mbox_unregister(mdev);
 }
 
 static struct platform_driver omap_mbox_driver = {
@@ -830,29 +767,7 @@ static struct platform_driver omap_mbox_driver = {
 		.of_match_table = of_match_ptr(omap_mailbox_of_match),
 	},
 };
-
-static int __init omap_mbox_init(void)
-{
-	int err;
-
-	err = class_register(&omap_mbox_class);
-	if (err)
-		return err;
-
-	err = platform_driver_register(&omap_mbox_driver);
-	if (err)
-		class_unregister(&omap_mbox_class);
-
-	return err;
-}
-subsys_initcall(omap_mbox_init);
-
-static void __exit omap_mbox_exit(void)
-{
-	platform_driver_unregister(&omap_mbox_driver);
-	class_unregister(&omap_mbox_class);
-}
-module_exit(omap_mbox_exit);
+module_platform_driver(omap_mbox_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");