devres: Add devm_is_action_added() helper

In some code we would like to know if the action in device managed resources
was added by devm_add_action() family of calls. Introduce a helper for that.

Reviewed-by: Raag Jadav <[email protected]>
Signed-off-by: Andy Shevchenko <[email protected]>
Reviewed-by: Zijun Hu <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>

Author: andy-shev

drivers/base/devres.c

@@ -759,6 +759,17 @@ int __devm_add_action(struct device *dev, void (*action)(void *), void *data, co
 }
 EXPORT_SYMBOL_GPL(__devm_add_action);
 
+bool devm_is_action_added(struct device *dev, void (*action)(void *), void *data)
+{
+	struct action_devres devres = {
+		.data = data,
+		.action = action,
+	};
+
+	return devres_find(dev, devm_action_release, devm_action_match, &devres);
+}
+EXPORT_SYMBOL_GPL(devm_is_action_added);
+
 /**
  * devm_remove_action_nowarn() - removes previously added custom action
  * @dev: Device that owns the action

include/linux/device/devres.h

@@ -165,4 +165,6 @@ static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(
 #define devm_add_action_or_reset(dev, action, data) \
 	__devm_add_action_or_reset(dev, action, data, #action)
 
+bool devm_is_action_added(struct device *dev, void (*action)(void *), void *data);
+
 #endif /* _DEVICE_DEVRES_H_ */