blob: 2be9683532573cb546432b651b6212565e8c66a1 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* of.c The helpers for hcd device tree support
*
* Copyright (C) 2016 Freescale Semiconductor, Inc.
* Author: Peter Chen <peter.chen@freescale.com>
*/
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/usb/of.h>
/**
* usb_of_get_child_node - Find the device node match port number
* @parent: the parent device node
* @portnum: the port number which device is connecting
*
* Find the node from device tree according to its port number.
*
* Return: A pointer to the node with incremented refcount if found, or
* %NULL otherwise.
*/
struct device_node *usb_of_get_child_node(struct device_node *parent,
int portnum)
{
struct device_node *node;
u32 port;
for_each_child_of_node(parent, node) {
if (!of_property_read_u32(node, "reg", &port)) {
if (port == portnum)
return node;
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(usb_of_get_child_node);
/**
* usb_of_get_companion_dev - Find the companion device
* @dev: the device pointer to find a companion
*
* Find the companion device from platform bus.
*
* Takes a reference to the returned struct device which needs to be dropped
* after use.
*
* Return: On success, a pointer to the companion device, %NULL on failure.
*/
struct device *usb_of_get_companion_dev(struct device *dev)
{
struct device_node *node;
struct platform_device *pdev = NULL;
node = of_parse_phandle(dev->of_node, "companion", 0);
if (node)
pdev = of_find_device_by_node(node);
of_node_put(node);
return pdev ? &pdev->dev : NULL;
}
EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);