1/*
2 * OF helpers for network devices.
3 *
4 * This file is released under the GPLv2
5 *
6 * Initially copied out of arch/powerpc/kernel/prom_parse.c
7 */
8#include <linux/etherdevice.h>
9#include <linux/kernel.h>
10#include <linux/of_net.h>
11#include <linux/phy.h>
12#include <linux/export.h>
13
14/**
15 * of_get_phy_mode - Get phy mode for given device_node
16 * @np:	Pointer to the given device_node
17 *
18 * The function gets phy interface string from property 'phy-mode' or
19 * 'phy-connection-type', and return its index in phy_modes table, or errno in
20 * error case.
21 */
22int of_get_phy_mode(struct device_node *np)
23{
24	const char *pm;
25	int err, i;
26
27	err = of_property_read_string(np, "phy-mode", &pm);
28	if (err < 0)
29		err = of_property_read_string(np, "phy-connection-type", &pm);
30	if (err < 0)
31		return err;
32
33	for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
34		if (!strcasecmp(pm, phy_modes(i)))
35			return i;
36
37	return -ENODEV;
38}
39EXPORT_SYMBOL_GPL(of_get_phy_mode);
40
41static const void *of_get_mac_addr(struct device_node *np, const char *name)
42{
43	struct property *pp = of_find_property(np, name, NULL);
44
45	if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value))
46		return pp->value;
47	return NULL;
48}
49
50/**
51 * Search the device tree for the best MAC address to use.  'mac-address' is
52 * checked first, because that is supposed to contain to "most recent" MAC
53 * address. If that isn't set, then 'local-mac-address' is checked next,
54 * because that is the default address.  If that isn't set, then the obsolete
55 * 'address' is checked, just in case we're using an old device tree.
56 *
57 * Note that the 'address' property is supposed to contain a virtual address of
58 * the register set, but some DTS files have redefined that property to be the
59 * MAC address.
60 *
61 * All-zero MAC addresses are rejected, because those could be properties that
62 * exist in the device tree, but were not set by U-Boot.  For example, the
63 * DTS could define 'mac-address' and 'local-mac-address', with zero MAC
64 * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
65 * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
66 * but is all zeros.
67*/
68const void *of_get_mac_address(struct device_node *np)
69{
70	const void *addr;
71
72	addr = of_get_mac_addr(np, "mac-address");
73	if (addr)
74		return addr;
75
76	addr = of_get_mac_addr(np, "local-mac-address");
77	if (addr)
78		return addr;
79
80	return of_get_mac_addr(np, "address");
81}
82EXPORT_SYMBOL(of_get_mac_address);
83