Commit 0ff5cc1e authored by Saravana Kannan's avatar Saravana Kannan Committed by Greg Kroah-Hartman
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of: property: Make sure child dependencies don't block probing of parent 



When creating device links to proxy the sync_state() needs of child
dependencies, create SYNC_STATE_ONLY device links so that children
dependencies don't block probing of the parent.

Also, differentiate between missing suppliers of parent device vs
missing suppliers of child devices so that driver core doesn't block
parent device probing when only child supplier dependencies are missing.

Signed-off-by: default avatarSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-5-saravanak@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 03324507

drivers/of/property.c

+12 −5
Original line number Diff line number Diff line
@@ -1018,10 +1018,10 @@ static bool of_is_ancestor_of(struct device_node *test_ancestor, 
 * - -EINVAL if the supplier link is invalid and should not be created

 * - -ENODEV if there is no device that corresponds to the supplier phandle

 */

static int of_link_to_phandle(struct device *dev, struct device_node *sup_np)

static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,

			      u32 dl_flags)

{

	struct device *sup_dev;

	u32 dl_flags = DL_FLAG_AUTOPROBE_CONSUMER;

	int ret = 0;

	struct device_node *tmp_np = sup_np;
@@ -1181,13 +1181,20 @@ static int of_link_property(struct device *dev, struct device_node *con_np, 
	unsigned int i = 0;

	bool matched = false;

	int ret = 0;

	u32 dl_flags;



	if (dev->of_node == con_np)

		dl_flags = DL_FLAG_AUTOPROBE_CONSUMER;

	else

		dl_flags = DL_FLAG_SYNC_STATE_ONLY;



	/* Do not stop at first failed link, link all available suppliers. */

	while (!matched && s->parse_prop) {

		while ((phandle = s->parse_prop(con_np, prop_name, i))) {

			matched = true;

			i++;

			if (of_link_to_phandle(dev, phandle) == -EAGAIN)

			if (of_link_to_phandle(dev, phandle, dl_flags)

								== -EAGAIN)

				ret = -EAGAIN;

			of_node_put(phandle);

		}
@@ -1205,10 +1212,10 @@ static int of_link_to_suppliers(struct device *dev, 


	for_each_property_of_node(con_np, p)

		if (of_link_property(dev, con_np, p->name))

			ret = -EAGAIN;

			ret = -ENODEV;



	for_each_child_of_node(con_np, child)

		if (of_link_to_suppliers(dev, child))

		if (of_link_to_suppliers(dev, child) && !ret)

			ret = -EAGAIN;



	return ret;