[PATCH v2 2/6] ASoC: aoa: Use helper function for_each_child_of_node_scoped()

[Dmitry Baryshkov]

On Mon, May 26, 2025 at 04:20:37PM +0800, Ai Chao wrote:
> 
> Hi Johannes:
> > > Hi Johannes:
> > > 
> > > > > "simplifies the code" is no need to callof_node_put() .
> > > > Fair. Except that's not what you _actually_ changed here. Like I said,
> > > > either it's buggy before or after.
> > > > 
> > > In the function i2sbus_probe, it not return a struct device_node, so , I
> > > think function for_each_child_of_node_scoped is better than
> > > for_each_child_of_node.
> > You still haven't explained why it's even correct.
> > 
> > johannes
> 
> The for_each_child_of_node() function is used to iterate over all child
> nodes of a device tree node.
> During each iteration, it retrieves a pointer to the child node via
> of_get_next_child() and automatically increments the node's reference count
> (of_node_get()).

This is not complete story, you missed the second part of it.

> Each call to of_get_next_child() increases the reference count (refcount) of
> the returned child node, ensuring that the node is not freed while in use.
> for_each_child_of_node() increments the child node's reference count in each
> iteration but does not decrement it automatically.
> If of_node_put() is not called manually, the reference count will never
> reach zero, resulting in a memory leak of the node.
> 
> Best regards,
> Ai Chao

-- 
With best wishes
Dmitry