1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * OF helpers for network devices. 4 * 5 * Initially copied out of arch/powerpc/kernel/prom_parse.c 6 */ 7#include <linux/etherdevice.h> 8#include <linux/kernel.h> 9#include <linux/of_net.h> 10#include <linux/of_platform.h> 11#include <linux/phy.h> 12#include <linux/export.h> 13#include <linux/device.h> 14 15/** 16 * of_get_phy_mode - Get phy mode for given device_node 17 * @np: Pointer to the given device_node 18 * @interface: Pointer to the result 19 * 20 * The function gets phy interface string from property 'phy-mode' or 21 * 'phy-connection-type'. The index in phy_modes table is set in 22 * interface and 0 returned. In case of error interface is set to 23 * PHY_INTERFACE_MODE_NA and an errno is returned, e.g. -ENODEV. 24 */ 25int of_get_phy_mode(struct device_node *np, phy_interface_t *interface) 26{ 27 const char *pm; 28 int err, i; 29 30 *interface = PHY_INTERFACE_MODE_NA; 31 32 err = of_property_read_string(np, "phy-mode", &pm); 33 if (err < 0) 34 err = of_property_read_string(np, "phy-connection-type", &pm); 35 if (err < 0) 36 return err; 37 38 for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++) 39 if (!strcasecmp(pm, phy_modes(i))) { 40 *interface = i; 41 return 0; 42 } 43 44 return -ENODEV; 45} 46EXPORT_SYMBOL_GPL(of_get_phy_mode); 47 48static const void *of_get_mac_addr(struct device_node *np, const char *name) 49{ 50 struct property *pp = of_find_property(np, name, NULL); 51 52 if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value)) 53 return pp->value; 54 return NULL; 55} 56 57static const void *of_get_mac_addr_nvmem(struct device_node *np) 58{ 59 int ret; 60 const void *mac; 61 u8 nvmem_mac[ETH_ALEN]; 62 struct platform_device *pdev = of_find_device_by_node(np); 63 64 if (!pdev) 65 return ERR_PTR(-ENODEV); 66 67 ret = nvmem_get_mac_address(&pdev->dev, &nvmem_mac); 68 if (ret) { 69 put_device(&pdev->dev); 70 return ERR_PTR(ret); 71 } 72 73 mac = devm_kmemdup(&pdev->dev, nvmem_mac, ETH_ALEN, GFP_KERNEL); 74 put_device(&pdev->dev); 75 if (!mac) 76 return ERR_PTR(-ENOMEM); 77 78 return mac; 79} 80 81/** 82 * Search the device tree for the best MAC address to use. 'mac-address' is 83 * checked first, because that is supposed to contain to "most recent" MAC 84 * address. If that isn't set, then 'local-mac-address' is checked next, 85 * because that is the default address. If that isn't set, then the obsolete 86 * 'address' is checked, just in case we're using an old device tree. If any 87 * of the above isn't set, then try to get MAC address from nvmem cell named 88 * 'mac-address'. 89 * 90 * Note that the 'address' property is supposed to contain a virtual address of 91 * the register set, but some DTS files have redefined that property to be the 92 * MAC address. 93 * 94 * All-zero MAC addresses are rejected, because those could be properties that 95 * exist in the device tree, but were not set by U-Boot. For example, the 96 * DTS could define 'mac-address' and 'local-mac-address', with zero MAC 97 * addresses. Some older U-Boots only initialized 'local-mac-address'. In 98 * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists 99 * but is all zeros. 100 * 101 * Return: Will be a valid pointer on success and ERR_PTR in case of error. 102*/ 103const void *of_get_mac_address(struct device_node *np) 104{ 105 const void *addr; 106 107 addr = of_get_mac_addr(np, "mac-address"); 108 if (addr) 109 return addr; 110 111 addr = of_get_mac_addr(np, "local-mac-address"); 112 if (addr) 113 return addr; 114 115 addr = of_get_mac_addr(np, "address"); 116 if (addr) 117 return addr; 118 119 return of_get_mac_addr_nvmem(np); 120} 121EXPORT_SYMBOL(of_get_mac_address); 122