diff options
Diffstat (limited to 'net/core/of_net.c')
| -rw-r--r-- | net/core/of_net.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/net/core/of_net.c b/net/core/of_net.c new file mode 100644 index 000000000000..f1a9bf7578e7 --- /dev/null +++ b/net/core/of_net.c @@ -0,0 +1,170 @@ +// 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> +#include <linux/nvmem-consumer.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; + + *interface = PHY_INTERFACE_MODE_NA; + + 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; +} +EXPORT_SYMBOL_GPL(of_get_phy_mode); + +static int of_get_mac_addr(struct device_node *np, const char *name, u8 *addr) +{ + struct property *pp = of_find_property(np, name, NULL); + + if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value)) { + memcpy(addr, pp->value, ETH_ALEN); + return 0; + } + return -ENODEV; +} + +static int of_get_mac_addr_nvmem(struct device_node *np, u8 *addr) +{ + struct platform_device *pdev = of_find_device_by_node(np); + struct nvmem_cell *cell; + const void *mac; + size_t len; + int ret; + + /* Try lookup by device first, there might be a nvmem_cell_lookup + * associated with a given device. + */ + if (pdev) { + ret = nvmem_get_mac_address(&pdev->dev, addr); + put_device(&pdev->dev); + return ret; + } + + cell = of_nvmem_cell_get(np, "mac-address"); + if (IS_ERR(cell)) + return PTR_ERR(cell); + + mac = nvmem_cell_read(cell, &len); + nvmem_cell_put(cell); + + if (IS_ERR(mac)) + return PTR_ERR(mac); + + if (len != ETH_ALEN || !is_valid_ether_addr(mac)) { + kfree(mac); + return -EINVAL; + } + + memcpy(addr, mac, ETH_ALEN); + kfree(mac); + + return 0; +} + +/** + * of_get_mac_address() + * @np: Caller's Device Node + * @addr: Pointer to a six-byte array for the result + * + * 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: 0 on success and errno in case of error. +*/ +int of_get_mac_address(struct device_node *np, u8 *addr) +{ + int ret; + + if (!np) + return -ENODEV; + + ret = of_get_mac_addr(np, "mac-address", addr); + if (!ret) + return 0; + + ret = of_get_mac_addr(np, "local-mac-address", addr); + if (!ret) + return 0; + + ret = of_get_mac_addr(np, "address", addr); + if (!ret) + return 0; + + return of_get_mac_addr_nvmem(np, addr); +} +EXPORT_SYMBOL(of_get_mac_address); + +/** + * of_get_ethdev_address() + * @np: Caller's Device Node + * @dev: Pointer to netdevice which address will be updated + * + * Search the device tree for the best MAC address to use. + * If found set @dev->dev_addr to that address. + * + * See documentation of of_get_mac_address() for more information on how + * the best address is determined. + * + * Return: 0 on success and errno in case of error. + */ +int of_get_ethdev_address(struct device_node *np, struct net_device *dev) +{ + u8 addr[ETH_ALEN]; + int ret; + + ret = of_get_mac_address(np, addr); + if (!ret) + eth_hw_addr_set(dev, addr); + return ret; +} +EXPORT_SYMBOL(of_get_ethdev_address); |