blob: 6e411821583e4f2fd71d108687dee528b767a7a0 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
* OF helpers for network devices.
* Initially copied out of arch/powerpc/kernel/prom_parse.c
#include <linux/etherdevice.h>
#include <linux/kernel.h>
#include <linux/of_net.h>
#include <linux/of_platform.h>
#include <linux/phy.h>
#include <linux/export.h>
#include <linux/device.h>
* of_get_phy_mode - Get phy mode for given device_node
* @np: Pointer to the given device_node
* @interface: Pointer to the result
* The function gets phy interface string from property 'phy-mode' or
* 'phy-connection-type'. The index in phy_modes table is set in
* interface and 0 returned. In case of error interface is set to
* PHY_INTERFACE_MODE_NA and an errno is returned, e.g. -ENODEV.
int of_get_phy_mode(struct device_node *np, phy_interface_t *interface)
const char *pm;
int err, i;
err = of_property_read_string(np, "phy-mode", &pm);
if (err < 0)
err = of_property_read_string(np, "phy-connection-type", &pm);
if (err < 0)
return err;
for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
if (!strcasecmp(pm, phy_modes(i))) {
*interface = i;
return 0;
return -ENODEV;
static const void *of_get_mac_addr(struct device_node *np, const char *name)
struct property *pp = of_find_property(np, name, NULL);
if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value))
return pp->value;
return NULL;
static const void *of_get_mac_addr_nvmem(struct device_node *np)
int ret;
const void *mac;
u8 nvmem_mac[ETH_ALEN];
struct platform_device *pdev = of_find_device_by_node(np);
if (!pdev)
return ERR_PTR(-ENODEV);
ret = nvmem_get_mac_address(&pdev->dev, &nvmem_mac);
if (ret) {
return ERR_PTR(ret);
mac = devm_kmemdup(&pdev->dev, nvmem_mac, ETH_ALEN, GFP_KERNEL);
if (!mac)
return ERR_PTR(-ENOMEM);
return mac;
* Search the device tree for the best MAC address to use. 'mac-address' is
* checked first, because that is supposed to contain to "most recent" MAC
* address. If that isn't set, then 'local-mac-address' is checked next,
* because that is the default address. If that isn't set, then the obsolete
* 'address' is checked, just in case we're using an old device tree. If any
* of the above isn't set, then try to get MAC address from nvmem cell named
* 'mac-address'.
* Note that the 'address' property is supposed to contain a virtual address of
* the register set, but some DTS files have redefined that property to be the
* MAC address.
* All-zero MAC addresses are rejected, because those could be properties that
* exist in the device tree, but were not set by U-Boot. For example, the
* DTS could define 'mac-address' and 'local-mac-address', with zero MAC
* addresses. Some older U-Boots only initialized 'local-mac-address'. In
* this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
* but is all zeros.
* Return: Will be a valid pointer on success and ERR_PTR in case of error.
const void *of_get_mac_address(struct device_node *np)
const void *addr;
addr = of_get_mac_addr(np, "mac-address");
if (addr)
return addr;
addr = of_get_mac_addr(np, "local-mac-address");
if (addr)
return addr;
addr = of_get_mac_addr(np, "address");
if (addr)
return addr;
return of_get_mac_addr_nvmem(np);