device connection: Find device connections also from device graphs

 */

#include <linux/device.h>

#include <linux/property.h>

static DEFINE_MUTEX(devcon_lock);

static LIST_HEAD(devcon_list);

typedef void *(*devcon_match_fn_t)(struct device_connection *con, int ep,

				   void *data);

static void *

fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,

			  void *data, devcon_match_fn_t match)

{

	struct device_connection con = { .id = con_id };

	struct fwnode_handle *ep;

	void *ret;

	fwnode_graph_for_each_endpoint(fwnode, ep) {

		con.fwnode = fwnode_graph_get_remote_port_parent(ep);

		if (!fwnode_device_is_available(con.fwnode))

			continue;

		ret = match(&con, -1, data);

		fwnode_handle_put(con.fwnode);

		if (ret) {

			fwnode_handle_put(ep);

			return ret;

		}

	}

	return NULL;

}

/**

 * device_connection_find_match - Find physical connection to a device

 * @dev: Device with the connection

 * caller is expecting to be returned.

 */

void *device_connection_find_match(struct device *dev, const char *con_id,

			       void *data,

			       void *(*match)(struct device_connection *con,

					      int ep, void *data))

				   void *data, devcon_match_fn_t match)

{

	struct fwnode_handle *fwnode = dev_fwnode(dev);

	const char *devname = dev_name(dev);

	struct device_connection *con;

	void *ret = NULL;

	if (!match)

		return NULL;

	if (fwnode) {

		ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);

		if (ret)

			return ret;

	}

	mutex_lock(&devcon_lock);

	list_for_each_entry(con, &devcon_list, list) {