Commit 5461f3fd authored by Dr. David Alan Gilbert's avatar Dr. David Alan Gilbert Committed by Lee Jones
Browse files

backlight: Remove notifier 



backlight_register_notifier and backlight_unregister_notifier have
been unused since commit 6cb634d0 ("ACPI: video: Remove code to
unregister acpi_video backlight when a native backlight registers")

With those not being called, it means that the backlight_notifier
list is always empty.

Remove the functions, the list itself and the enum used in the
notifications.

Signed-off-by: default avatarDr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: default avatarDaniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: default avatarSimona Vetter <simona.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20240919232758.639925-1-linux@treblig.org


Signed-off-by: default avatarLee Jones <lee@kernel.org>
parent 1a2dc9bf

drivers/video/backlight/backlight.c

+0 −42
Original line number Diff line number Diff line
@@ -65,7 +65,6 @@ 


static struct list_head backlight_dev_list;

static struct mutex backlight_dev_list_mutex;

static struct blocking_notifier_head backlight_notifier;



static const char *const backlight_types[] = {

	[BACKLIGHT_RAW] = "raw",
@@ -467,9 +466,6 @@ struct backlight_device *backlight_device_register(const char *name, 
	list_add(&new_bd->entry, &backlight_dev_list);

	mutex_unlock(&backlight_dev_list_mutex);



	blocking_notifier_call_chain(&backlight_notifier,

				     BACKLIGHT_REGISTERED, new_bd);



	return new_bd;

}

EXPORT_SYMBOL(backlight_device_register);
@@ -539,9 +535,6 @@ void backlight_device_unregister(struct backlight_device *bd) 
	mutex_unlock(&pmac_backlight_mutex);

#endif



	blocking_notifier_call_chain(&backlight_notifier,

				     BACKLIGHT_UNREGISTERED, bd);



	mutex_lock(&bd->ops_lock);

	bd->ops = NULL;

	mutex_unlock(&bd->ops_lock);
@@ -566,40 +559,6 @@ static int devm_backlight_device_match(struct device *dev, void *res, 
	return *r == data;

}



/**

 * backlight_register_notifier - get notified of backlight (un)registration

 * @nb: notifier block with the notifier to call on backlight (un)registration

 *

 * Register a notifier to get notified when backlight devices get registered

 * or unregistered.

 *

 * RETURNS:

 *

 * 0 on success, otherwise a negative error code

 */

int backlight_register_notifier(struct notifier_block *nb)

{

	return blocking_notifier_chain_register(&backlight_notifier, nb);

}

EXPORT_SYMBOL(backlight_register_notifier);



/**

 * backlight_unregister_notifier - unregister a backlight notifier

 * @nb: notifier block to unregister

 *

 * Register a notifier to get notified when backlight devices get registered

 * or unregistered.

 *

 * RETURNS:

 *

 * 0 on success, otherwise a negative error code

 */

int backlight_unregister_notifier(struct notifier_block *nb)

{

	return blocking_notifier_chain_unregister(&backlight_notifier, nb);

}

EXPORT_SYMBOL(backlight_unregister_notifier);



/**

 * devm_backlight_device_register - register a new backlight device

 * @dev: the device to register
@@ -767,7 +726,6 @@ static int __init backlight_class_init(void) 


	INIT_LIST_HEAD(&backlight_dev_list);

	mutex_init(&backlight_dev_list_mutex);

	BLOCKING_INIT_NOTIFIER_HEAD(&backlight_notifier);



	return 0;

}

include/linux/backlight.h

+0 −20
Original line number Diff line number Diff line
@@ -66,24 +66,6 @@ enum backlight_type { 
	BACKLIGHT_TYPE_MAX,

};



/**

 * enum backlight_notification - the type of notification

 *

 * The notifications that is used for notification sent to the receiver

 * that registered notifications using backlight_register_notifier().

 */

enum backlight_notification {

	/**

	 * @BACKLIGHT_REGISTERED: The backlight device is registered.

	 */

	BACKLIGHT_REGISTERED,



	/**

	 * @BACKLIGHT_UNREGISTERED: The backlight revice is unregistered.

	 */

	BACKLIGHT_UNREGISTERED,

};



/** enum backlight_scale - the type of scale used for brightness values

 *

 * The type of scale used for brightness values.
@@ -421,8 +403,6 @@ void devm_backlight_device_unregister(struct device *dev, 
				      struct backlight_device *bd);

void backlight_force_update(struct backlight_device *bd,

			    enum backlight_update_reason reason);

int backlight_register_notifier(struct notifier_block *nb);

int backlight_unregister_notifier(struct notifier_block *nb);

struct backlight_device *backlight_device_get_by_name(const char *name);

struct backlight_device *backlight_device_get_by_type(enum backlight_type type);

int backlight_device_set_brightness(struct backlight_device *bd,