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/nvmem-consumer.h>
11#include <linux/of_net.h>
12#include <linux/phy.h>
13#include <linux/export.h>
14
15/**
16 * of_get_phy_mode - Get phy mode for given device_node
17 * @np: Pointer to the given device_node
18 *
19 * The function gets phy interface string from property 'phy-mode' or
20 * 'phy-connection-type', and return its index in phy_modes table, or errno in
21 * error case.
22 */
23int of_get_phy_mode(struct device_node *np)
24{
25 const char *pm;
26 int err, i;
27
28 err = of_property_read_string(np, "phy-mode", &pm);
29 if (err < 0)
30 err = of_property_read_string(np, "phy-connection-type", &pm);
31 if (err < 0)
32 return err;
33
34 for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
35 if (!strcasecmp(pm, phy_modes(i)))
36 return i;
37
38 return -ENODEV;
39}
40EXPORT_SYMBOL_GPL(of_get_phy_mode);
41
42static const void *of_get_mac_addr(struct device_node *np, const char *name)
43{
44 struct property *pp = of_find_property(np, name, NULL);
45
46 if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value))
47 return pp->value;
48 return NULL;
49}
50
51/**
52 * Search the device tree for the best MAC address to use. 'mac-address' is
53 * checked first, because that is supposed to contain to "most recent" MAC
54 * address. If that isn't set, then 'local-mac-address' is checked next,
55 * because that is the default address. If that isn't set, then the obsolete
56 * 'address' is checked, just in case we're using an old device tree.
57 *
58 * Note that the 'address' property is supposed to contain a virtual address of
59 * the register set, but some DTS files have redefined that property to be the
60 * MAC address.
61 *
62 * All-zero MAC addresses are rejected, because those could be properties that
63 * exist in the device tree, but were not set by U-Boot. For example, the
64 * DTS could define 'mac-address' and 'local-mac-address', with zero MAC
65 * addresses. Some older U-Boots only initialized 'local-mac-address'. In
66 * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
67 * but is all zeros.
68*/
69const void *of_get_mac_address(struct device_node *np)
70{
71 const void *addr;
72
73 addr = of_get_mac_addr(np, "mac-address");
74 if (addr)
75 return addr;
76
77 addr = of_get_mac_addr(np, "local-mac-address");
78 if (addr)
79 return addr;
80
81 return of_get_mac_addr(np, "address");
82}
83EXPORT_SYMBOL(of_get_mac_address);
84