2023-08-10 18:13:45

by Ivan Orlov

Subject: [PATCH] leds: make leds_class a static const structure

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

Suggested-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Ivan Orlov <[email protected]>
---
drivers/leds/led-class.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 6dae56b914fe..2f702d50f5fb 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -22,7 +22,6 @@
#include <linux/of.h>
#include "leds.h"

-static struct class *leds_class;
static DEFINE_MUTEX(leds_lookup_lock);
static LIST_HEAD(leds_lookup_list);

@@ -234,6 +233,12 @@ static struct led_classdev *led_module_get(struct device *led_dev)
return led_cdev;
}

+static const struct class leds_class = {
+ .name = "leds",
+ .dev_groups = led_groups,
+ .pm = &leds_class_dev_pm_ops,
+};
+
/**
* of_led_get() - request a LED device via the LED framework
* @np: device node to get the LED device from
@@ -251,7 +256,7 @@ struct led_classdev *of_led_get(struct device_node *np, int index)
if (!led_node)
return ERR_PTR(-ENOENT);

- led_dev = class_find_device_by_of_node(leds_class, led_node);
+ led_dev = class_find_device_by_of_node(&leds_class, led_node);
of_node_put(led_node);
put_device(led_dev);

@@ -346,7 +351,7 @@ struct led_classdev *led_get(struct device *dev, char *con_id)
if (!provider)
return ERR_PTR(-ENOENT);

- led_dev = class_find_device_by_name(leds_class, provider);
+ led_dev = class_find_device_by_name(&leds_class, provider);
kfree_const(provider);

return led_module_get(led_dev);
@@ -412,7 +417,7 @@ static int led_classdev_next_name(const char *init_name, char *name,
strscpy(name, init_name, len);

while ((ret < len) &&
- (dev = class_find_device_by_name(leds_class, name))) {
+ (dev = class_find_device_by_name(&leds_class, name))) {
put_device(dev);
ret = snprintf(name, len, "%s_%u", init_name, ++i);
}
@@ -468,8 +473,8 @@ int led_classdev_register_ext(struct device *parent,

mutex_init(&led_cdev->led_access);
mutex_lock(&led_cdev->led_access);
- led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
- led_cdev, led_cdev->groups, "%s", final_name);
+ led_cdev->dev = device_create_with_groups(&leds_class, parent, 0,
+ led_cdev, led_cdev->groups, "%s", final_name);
if (IS_ERR(led_cdev->dev)) {
mutex_unlock(&led_cdev->led_access);
return PTR_ERR(led_cdev->dev);
@@ -626,17 +631,12 @@ EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);

static int __init leds_init(void)
{
- leds_class = class_create("leds");
- if (IS_ERR(leds_class))
- return PTR_ERR(leds_class);
- leds_class->pm = &leds_class_dev_pm_ops;
- leds_class->dev_groups = led_groups;
- return 0;
+ return class_register(&leds_class);
}

static void __exit leds_exit(void)
{
- class_destroy(leds_class);
+ class_unregister(&leds_class);
}

subsys_initcall(leds_init);
--
2.34.1

2023-08-18 19:53:10

by Lee Jones

Subject: Re: (subset) [PATCH] leds: make leds_class a static const structure

On Thu, 10 Aug 2023 21:49:05 +0400, Ivan Orlov wrote:
> Now that the driver core allows for struct class to be in read-only
> memory, move the leds_class structure to be declared at build time
> placing it into read-only memory, instead of having to be dynamically
> allocated at boot time.
>
>

Applied, thanks!

[1/1] leds: make leds_class a static const structure
commit: 43a707ae58406200597b03a5be782e726b3c175b

--
Lee Jones [李琼斯]