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

[Johannes Berg <johannes@sipsolutions.net>]

On Mon, 2025-05-26 at 16:20 +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()).
> 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.

Yes, good! Now show that you can apply what you've learned to the
specific code (and changes) at hand.

johannes