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authorJakub Kicinski <kuba@kernel.org>2021-10-06 18:06:54 -0700
committerDavid S. Miller <davem@davemloft.net>2021-10-07 13:39:51 +0100
commite330fb14590c5c80f7195c3d8c9b4bcf79e1a5cd (patch)
treeb2c5408e5de96b2ff19f086b0bacbf63572ad148 /net/core/of_net.c
parent944b33ca7bc58fc1c3d6c14702a59e925033a268 (diff)
of: net: move of_net under net/
Rob suggests to move of_net.c from under drivers/of/ somewhere to the networking code. Suggested-by: Rob Herring <robh@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/of_net.c')
-rw-r--r--net/core/of_net.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/net/core/of_net.c b/net/core/of_net.c
new file mode 100644
index 000000000000..dbac3a172a11
--- /dev/null
+++ b/net/core/of_net.c
@@ -0,0 +1,145 @@
+// 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);