1 From: John Crispin <blogic@openwrt.org>
2 Subject: NET: add mtd-mac-address support to of_get_mac_address()
4 Many embedded devices have information such as mac addresses stored inside mtd
5 devices. This patch allows us to add a property inside a node describing a
6 network interface. The new property points at a mtd partition with an offset
7 where the mac address can be found.
9 Signed-off-by: John Crispin <blogic@openwrt.org>
10 Signed-off-by: Felix Fietkau <nbd@nbd.name>
12 drivers/of/of_net.c | 37 +++++++++++++++++++++++++++++++++++++
13 include/linux/of_net.h | 1 +
14 2 files changed, 38 insertions(+)
16 --- a/drivers/of/of_net.c
17 +++ b/drivers/of/of_net.c
19 #include <linux/of_net.h>
20 #include <linux/phy.h>
21 #include <linux/export.h>
22 +#include <linux/mtd/mtd.h>
25 * of_get_phy_mode - Get phy mode for given device_node
26 @@ -38,7 +39,7 @@ int of_get_phy_mode(struct device_node *
28 EXPORT_SYMBOL_GPL(of_get_phy_mode);
30 -static const void *of_get_mac_addr(struct device_node *np, const char *name)
31 +static void *of_get_mac_addr(struct device_node *np, const char *name)
33 struct property *pp = of_find_property(np, name, NULL);
35 @@ -47,6 +48,79 @@ static const void *of_get_mac_addr(struc
39 +static const void *of_get_mac_address_mtd(struct device_node *np)
42 + struct device_node *mtd_np = NULL;
43 + struct property *prop;
46 + struct mtd_info *mtd;
55 + list = of_get_property(np, "mtd-mac-address", &size);
56 + if (!list || (size != (2 * sizeof(*list))))
59 + phandle = be32_to_cpup(list++);
61 + mtd_np = of_find_node_by_phandle(phandle);
66 + part = of_get_property(mtd_np, "label", NULL);
68 + part = mtd_np->name;
70 + mtd = get_mtd_device_nm(part);
74 + ret = mtd_read(mtd, be32_to_cpup(list), 6, &retlen, mac);
75 + put_mtd_device(mtd);
77 + if (of_property_read_u32(np, "mtd-mac-address-increment-byte", &inc_idx))
82 + if (!of_property_read_u32(np, "mtd-mac-address-increment", &mac_inc))
83 + mac[inc_idx] += mac_inc;
85 + if (!is_valid_ether_addr(mac))
88 + addr = of_get_mac_addr(np, "mac-address");
90 + memcpy(addr, mac, ETH_ALEN);
94 + prop = kzalloc(sizeof(*prop), GFP_KERNEL);
98 + prop->name = "mac-address";
99 + prop->length = ETH_ALEN;
100 + prop->value = kmemdup(mac, ETH_ALEN, GFP_KERNEL);
101 + if (!prop->value || of_add_property(np, prop))
104 + return prop->value;
106 + kfree(prop->value);
113 * Search the device tree for the best MAC address to use. 'mac-address' is
114 * checked first, because that is supposed to contain to "most recent" MAC
115 @@ -64,11 +138,18 @@ static const void *of_get_mac_addr(struc
116 * addresses. Some older U-Boots only initialized 'local-mac-address'. In
117 * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
120 + * If a mtd-mac-address property exists, try to fetch the MAC address from the
121 + * specified mtd device, and store it as a 'mac-address' property
123 const void *of_get_mac_address(struct device_node *np)
127 + addr = of_get_mac_address_mtd(np);
131 addr = of_get_mac_addr(np, "mac-address");