Commit cda12ba5 authored by Ricardo B. Marliere's avatar Ricardo B. Marliere Committed by Lee Jones
Browse files

backlight: Make backlight_class constant 



Since commit 43a7206b ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the backlight_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarRicardo B. Marliere <ricardo@marliere.net>
Reviewed-by: default avatarDaniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240305-class_cleanup-backlight-v1-1-c0e15cc25be1@marliere.net


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent e962f13b

drivers/video/backlight/backlight.c

+16 −13
Original line number Diff line number Diff line
@@ -319,8 +319,6 @@ static ssize_t scale_show(struct device *dev, 
}

static DEVICE_ATTR_RO(scale);



static struct class *backlight_class;



#ifdef CONFIG_PM_SLEEP

static int backlight_suspend(struct device *dev)

{
@@ -371,6 +369,12 @@ static struct attribute *bl_device_attrs[] = { 
};

ATTRIBUTE_GROUPS(bl_device);



static const struct class backlight_class = {

	.name = "backlight",

	.dev_groups = bl_device_groups,

	.pm = &backlight_class_dev_pm_ops,

};



/**

 * backlight_force_update - tell the backlight subsystem that hardware state

 *   has changed
@@ -420,7 +424,7 @@ struct backlight_device *backlight_device_register(const char *name, 
	mutex_init(&new_bd->update_lock);

	mutex_init(&new_bd->ops_lock);



	new_bd->dev.class = backlight_class;

	new_bd->dev.class = &backlight_class;

	new_bd->dev.parent = parent;

	new_bd->dev.release = bl_device_release;

	dev_set_name(&new_bd->dev, "%s", name);
@@ -512,7 +516,7 @@ struct backlight_device *backlight_device_get_by_name(const char *name) 
{

	struct device *dev;



	dev = class_find_device_by_name(backlight_class, name);

	dev = class_find_device_by_name(&backlight_class, name);



	return dev ? to_backlight_device(dev) : NULL;

}
@@ -680,7 +684,7 @@ struct backlight_device *of_find_backlight_by_node(struct device_node *node) 
{

	struct device *dev;



	dev = class_find_device(backlight_class, NULL, node, of_parent_match);

	dev = class_find_device(&backlight_class, NULL, node, of_parent_match);



	return dev ? to_backlight_device(dev) : NULL;

}
@@ -748,20 +752,19 @@ EXPORT_SYMBOL(devm_of_find_backlight); 


static void __exit backlight_class_exit(void)

{

	class_destroy(backlight_class);

	class_unregister(&backlight_class);

}



static int __init backlight_class_init(void)

{

	backlight_class = class_create("backlight");

	if (IS_ERR(backlight_class)) {

		pr_warn("Unable to create backlight class; errno = %ld\n",

			PTR_ERR(backlight_class));

		return PTR_ERR(backlight_class);

	int ret;



	ret = class_register(&backlight_class);

	if (ret) {

		pr_warn("Unable to create backlight class; errno = %d\n", ret);

		return ret;

	}



	backlight_class->dev_groups = bl_device_groups;

	backlight_class->pm = &backlight_class_dev_pm_ops;

	INIT_LIST_HEAD(&backlight_dev_list);

	mutex_init(&backlight_dev_list_mutex);

	BLOCKING_INIT_NOTIFIER_HEAD(&backlight_notifier);