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>

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);