int hwspin_lock_free()

in hwspinlock_core.c [800:839]

• 28 lines of code
• 3 McCabe index (conditional complexity)

int hwspin_lock_free(struct hwspinlock *hwlock)
{
	struct device *dev;
	struct hwspinlock *tmp;
	int ret;

	if (!hwlock) {
		pr_err("invalid hwlock\n");
		return -EINVAL;
	}

	dev = hwlock->bank->dev;
	mutex_lock(&hwspinlock_tree_lock);

	/* make sure the hwspinlock is used */
	ret = radix_tree_tag_get(&hwspinlock_tree, hwlock_to_id(hwlock),
							HWSPINLOCK_UNUSED);
	if (ret == 1) {
		dev_err(dev, "%s: hwlock is already free\n", __func__);
		dump_stack();
		ret = -EINVAL;
		goto out;
	}

	/* notify the underlying device that power is not needed */
	pm_runtime_put(dev);

	/* mark this hwspinlock as available */
	tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock_to_id(hwlock),
							HWSPINLOCK_UNUSED);

	/* sanity check (this shouldn't happen) */
	WARN_ON(tmp != hwlock);

	module_put(dev->driver->owner);

out:
	mutex_unlock(&hwspinlock_tree_lock);
	return ret;
}