Hi Jean-François, On Tue, Sep 02, 2025 at 03:04:39PM -0400, Jean-François Lessard wrote: > Add scoped versions of fwnode child node iterators that automatically > handle reference counting cleanup using the __free() attribute: > > - fwnode_for_each_child_node_scoped() > - fwnode_for_each_available_child_node_scoped() > > These macros follow the same pattern as existing scoped iterators in the > kernel, ensuring fwnode references are automatically released when the > iterator variable goes out of scope. This prevents resource leaks and > eliminates the need for manual cleanup in error paths. > > The implementation mirrors the non-scoped variants but uses > __free(fwnode_handle) for automatic resource management, providing a > safer and more convenient interface for drivers iterating over firmware > node children. > > Signed-off-by: Jean-François Lessard <jefflessard3@xxxxxxxxx> > --- > > Notes: > checkpatch reports false positives that are intentionally ignored: > MACRO_ARG_REUSE, MACRO_ARG_PRECEDENCE > This is a standard iterator pattern following kernel conventions. > > include/linux/property.h | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/include/linux/property.h b/include/linux/property.h > index 82f0cb3ab..862e20813 100644 > --- a/include/linux/property.h > +++ b/include/linux/property.h > @@ -176,6 +176,16 @@ struct fwnode_handle *fwnode_get_next_available_child_node( > for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\ > child = fwnode_get_next_available_child_node(fwnode, child)) > > +#define fwnode_for_each_child_node_scoped(fwnode, child) \ > + for (struct fwnode_handle *child __free(fwnode_handle) = \ > + fwnode_get_next_child_node(fwnode, NULL); \ > + child; child = fwnode_get_next_child_node(fwnode, child)) > + > +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \ > + for (struct fwnode_handle *child __free(fwnode_handle) = \ > + fwnode_get_next_available_child_node(fwnode, NULL); \ > + child; child = fwnode_get_next_available_child_node(fwnode, child)) > + Do we really need the available variant? Please see <URL:https://lore.kernel.org/linux-acpi/Zwj12J5bTNUEnxA0@kekkonen.localdomain/>. I'll post a patch to remove fwnode_get_next_available_child_node(), too. > struct fwnode_handle *device_get_next_child_node(const struct device *dev, > struct fwnode_handle *child); > -- Kind regards, Sakari Ailus
