Re: [PATCH v2 04/12] software node: Implement .get_reference_args fwnode operation

Rafael J. Wysocki
2019-04-12T08:48:55Z

On Wed, Apr 10, 2019 at 5:26 PM Heikki Krogerus
<heikki.krogerus@linux.intel.com> wrote:
>
> This makes it possible to support drivers that use
> fwnode_property_get_reference_args() function.
>
> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> ---
> drivers/base/swnode.c | 56 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 56 insertions(+)
>
> diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
> index 39b8f8f35cfe..d6a9b56cb073 100644
> --- a/drivers/base/swnode.c
> +++ b/drivers/base/swnode.c
> @@ -534,6 +534,61 @@ software_node_get_named_child_node(const struct fwnode_handle *fwnode,
> return NULL;
> }
>
> +static int
> +software_node_get_reference_args(const struct fwnode_handle *fwnode,
> + const char *propname, const char *nargs_prop,
> + unsigned int nargs, unsigned int index,
> + struct fwnode_reference_args *args)
> +{
> + struct software_node *swnode = to_software_node(fwnode);
> + struct software_node_reference *ref;
> + const struct property_entry *prop;
> + int ret = -ENOENT;
> + int i;
> +
> + mutex_lock(&swnode->lock);
> +
> + if (!swnode || list_empty(&swnode->references))
> + goto err_unlock;
> +
> + if (nargs_prop) {
> + prop = property_entry_get(swnode->properties, nargs_prop);
> + if (!prop) {
> + ret = -EINVAL;
> + goto err_unlock;
> + }
> +
> + nargs = prop->value.u32_data;
> + }
> +
> + if (nargs > NR_FWNODE_REFERENCE_ARGS) {
> + ret = -EINVAL;
> + goto err_unlock;
> + }
> +
> + list_for_each_entry(ref, &swnode->references, list) {
> + if (strcmp(ref->name, propname))
> + continue;
> +
> + if (index > (ref->nrefs - 1))
> + break;
> +
> + args->nargs = nargs;
> + args->fwnode = software_node_get(ref->args[index].fwnode);
> +
> + for (i = 0; i < nargs; i++)
> + args->args[i] = ref->args[index].args[i];

If nargs is provided by the caller, can't it be greater than the
number of args[index].args[] entries?

> +
> + ret = 0;
> + break;
> + }
> +
> +err_unlock:
> + mutex_unlock(&swnode->lock);
> +
> + return ret;
> +}
> +
> static const struct fwnode_operations software_node_ops = {
> .get = software_node_get,
> .put = software_node_put,
> @@ -543,6 +598,7 @@ static const struct fwnode_operations software_node_ops = {
> .get_parent = software_node_get_parent,
> .get_next_child_node = software_node_get_next_child,
> .get_named_child_node = software_node_get_named_child_node,
> + .get_reference_args = software_node_get_reference_args,
> };
>
> /* -------------------------------------------------------------------------- */