USB: gadget: udc: core: make udc_class a static const structure

Now that the driver core allows for struct class to be in read-only
memory, move the udc_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index 52e6d2e..b2bb633 100644 (file)
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -50,7 +50,7 @@ struct usb_udc {
        bool                            started;
 };
 
-static struct class *udc_class;
+static const struct class udc_class;
 static LIST_HEAD(udc_list);
 
 /* Protects udc_list, udc->driver, driver->is_bound, and related calls */
@@ -1312,7 +1312,7 @@ int usb_add_gadget(struct usb_gadget *gadget)
 
        device_initialize(&udc->dev);
        udc->dev.release = usb_udc_release;
-       udc->dev.class = udc_class;
+       udc->dev.class = &udc_class;
        udc->dev.groups = usb_udc_attr_groups;
        udc->dev.parent = gadget->dev.parent;
        ret = dev_set_name(&udc->dev, "%s",
@@ -1774,6 +1774,11 @@ static int usb_udc_uevent(const struct device *dev, struct kobj_uevent_env *env)
        return 0;
 }
 
+static const struct class udc_class = {
+       .name           = "udc",
+       .dev_uevent     = usb_udc_uevent,
+};
+
 static const struct bus_type gadget_bus_type = {
        .name = "gadget",
        .probe = gadget_bind_driver,
@@ -1785,18 +1790,13 @@ static int __init usb_udc_init(void)
 {
        int rc;
 
-       udc_class = class_create("udc");
-       if (IS_ERR(udc_class)) {
-               pr_err("failed to create udc class --> %ld\n",
-                               PTR_ERR(udc_class));
-               return PTR_ERR(udc_class);
-       }
-
-       udc_class->dev_uevent = usb_udc_uevent;
+       rc = class_register(&udc_class);
+       if (rc)
+               return rc;
 
        rc = bus_register(&gadget_bus_type);
        if (rc)
-               class_destroy(udc_class);
+               class_unregister(&udc_class);
        return rc;
 }
 subsys_initcall(usb_udc_init);
@@ -1804,7 +1804,7 @@ subsys_initcall(usb_udc_init);
 static void __exit usb_udc_exit(void)
 {
        bus_unregister(&gadget_bus_type);
-       class_destroy(udc_class);
+       class_unregister(&udc_class);
 }
 module_exit(usb_udc_exit);