Re: [PATCH v1 5/5] of: property: Skip adding device links to suppliers that aren't devices

From: Rob Herring
Date: Mon Nov 04 2019 - 10:18:54 EST


On Mon, Oct 28, 2019 at 5:00 PM Saravana Kannan <saravanak@xxxxxxxxxx> wrote:
>
> Some devices need to be initialized really early and can't wait for
> driver core or drivers to be functional. These devices are typically
> initialized without creating a struct device for their device nodes.
>
> If a supplier ends up being one of these devices, skip trying to add
> device links to them.
>
> Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
> ---
> drivers/of/property.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index f16f85597ccc..21c9d251318a 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1038,6 +1038,7 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
> struct device *sup_dev;
> int ret = 0;
> struct device_node *tmp_np = sup_np;
> + int is_populated;
>
> of_node_get(sup_np);
> /*
> @@ -1062,9 +1063,10 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
> return -EINVAL;
> }
> sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
> + is_populated = of_node_check_flag(sup_np, OF_POPULATED);
> of_node_put(sup_np);
> if (!sup_dev)
> - return -EAGAIN;
> + return is_populated ? 0 : -EAGAIN;

You're only using the flag in one spot and a comment would be good
here, so I'd just do:

if (of_node_check_flag(sup_np, OF_POPULATED))
return 0; /* Early device without a struct device */

> if (!device_link_add(dev, sup_dev, dl_flags))
> ret = -EAGAIN;
> put_device(sup_dev);
> --
> 2.24.0.rc0.303.g954a862665-goog
>