Revert "hwspinlock: Introduce hwspin_lock_bust()"

This reverts commit 5bfff48f58.

Documentation/locking/hwspinlock.rst

@@ -85,17 +85,6 @@ is already free).
 
 Should be called from a process context (might sleep).
 
-::
-
-  int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id);
-
-After verifying the owner of the hwspinlock, release a previously acquired
-hwspinlock; returns 0 on success, or an appropriate error code on failure
-(e.g. -EOPNOTSUPP if the bust operation is not defined for the specific
-hwspinlock).
-
-Should be called from a process context (might sleep).
-
 ::
 
   int hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int timeout);

drivers/hwspinlock/hwspinlock_core.c

@@ -302,34 +302,6 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
 }
 EXPORT_SYMBOL_GPL(__hwspin_unlock);
 
-/**
- * hwspin_lock_bust() - bust a specific hwspinlock
- * @hwlock: a previously-acquired hwspinlock which we want to bust
- * @id: identifier of the remote lock holder, if applicable
- *
- * This function will bust a hwspinlock that was previously acquired as
- * long as the current owner of the lock matches the id given by the caller.
- *
- * Context: Process context.
- *
- * Returns: 0 on success, or -EINVAL if the hwspinlock does not exist, or
- * the bust operation fails, and -EOPNOTSUPP if the bust operation is not
- * defined for the hwspinlock.
- */
-int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id)
-{
-	if (WARN_ON(!hwlock))
-		return -EINVAL;
-
-	if (!hwlock->bank->ops->bust) {
-		pr_err("bust operation not defined\n");
-		return -EOPNOTSUPP;
-	}
-
-	return hwlock->bank->ops->bust(hwlock, id);
-}
-EXPORT_SYMBOL_GPL(hwspin_lock_bust);
-
 /**
  * of_hwspin_lock_simple_xlate - translate hwlock_spec to return a lock id
  * @bank: the hwspinlock device bank

drivers/hwspinlock/hwspinlock_internal.h

@@ -21,8 +21,6 @@ struct hwspinlock_device;
  * @trylock: make a single attempt to take the lock. returns 0 on
  *	     failure and true on success. may _not_ sleep.
  * @unlock:  release the lock. always succeed. may _not_ sleep.
- * @bust:    optional, platform-specific bust handler, called by hwspinlock
- *	     core to bust a specific lock.
  * @relax:   optional, platform-specific relax handler, called by hwspinlock
  *	     core while spinning on a lock, between two successive
  *	     invocations of @trylock. may _not_ sleep.
@@ -30,7 +28,6 @@ struct hwspinlock_device;
 struct hwspinlock_ops {
 	int (*trylock)(struct hwspinlock *lock);
 	void (*unlock)(struct hwspinlock *lock);
-	int (*bust)(struct hwspinlock *lock, unsigned int id);
 	void (*relax)(struct hwspinlock *lock);
 };
 

include/linux/hwspinlock.h

@@ -68,7 +68,6 @@ int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int,
 int __hwspin_trylock(struct hwspinlock *, int, unsigned long *);
 void __hwspin_unlock(struct hwspinlock *, int, unsigned long *);
 int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name);
-int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id);
 int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock);
 struct hwspinlock *devm_hwspin_lock_request(struct device *dev);
 struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev,
@@ -128,11 +127,6 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
 {
 }
 
-static inline int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id)
-{
-	return 0;
-}
-
 static inline int of_hwspin_lock_get_id(struct device_node *np, int index)
 {
 	return 0;