blob: 3de4f8873984d2d04749f2f87b8b5c0fb2b9f59b [file] [log] [blame]
Peter Chen69bec722016-02-19 17:26:15 +08001/*
2 * of.c The helpers for hcd device tree support
3 *
4 * Copyright (C) 2016 Freescale Semiconductor, Inc.
5 * Author: Peter Chen <peter.chen@freescale.com>
6 *
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 of
9 * the License as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20#include <linux/of.h>
Peter Chen0573f2c2016-06-15 11:25:43 +080021#include <linux/usb/of.h>
Peter Chen69bec722016-02-19 17:26:15 +080022
23/**
24 * usb_of_get_child_node - Find the device node match port number
25 * @parent: the parent device node
26 * @portnum: the port number which device is connecting
27 *
28 * Find the node from device tree according to its port number.
29 *
30 * Return: On success, a pointer to the device node, %NULL on failure.
31 */
32struct device_node *usb_of_get_child_node(struct device_node *parent,
33 int portnum)
34{
35 struct device_node *node;
36 u32 port;
37
38 for_each_child_of_node(parent, node) {
39 if (!of_property_read_u32(node, "reg", &port)) {
40 if (port == portnum)
41 return node;
42 }
43 }
44
45 return NULL;
46}
47EXPORT_SYMBOL_GPL(usb_of_get_child_node);
48