target/linux/generic/patches-4.3/681-NET-add-of_get_mac_address_mtd.patch

   1 From: John Crispin <blogic@openwrt.org>
   2 Date: Sun, 27 Jul 2014 09:40:01 +0100
   3 Subject: NET: add mtd-mac-address support to of_get_mac_address()
   4
   5 Many embedded devices have information such as mac addresses stored inside mtd
   6 devices. This patch allows us to add a property inside a node describing a
   7 network interface. The new property points at a mtd partition with an offset
   8 where the mac address can be found.
   9
  10 Signed-off-by: John Crispin <blogic@openwrt.org>
  11 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
  12 ---
  13  drivers/of/of_net.c    |   37 +++++++++++++++++++++++++++++++++++++
  14  include/linux/of_net.h |    1 +
  15  2 files changed, 38 insertions(+)
  16
  17 --- a/drivers/of/of_net.c
  18 +++ b/drivers/of/of_net.c
  19 @@ -10,6 +10,7 @@
  20  #include <linux/of_net.h>
  21  #include <linux/phy.h>
  22  #include <linux/export.h>
  23 +#include <linux/mtd/mtd.h>
  24
  25  /**
  26   * of_get_phy_mode - Get phy mode for given device_node
  27 @@ -47,6 +48,66 @@ static const void *of_get_mac_addr(struc
  28         return NULL;
  29  }
  30
  31 +static const void *of_get_mac_address_mtd(struct device_node *np)
  32 +{
  33 +#ifdef CONFIG_MTD
  34 +       struct device_node *mtd_np = NULL;
  35 +       struct property *prop;
  36 +       size_t retlen;
  37 +       int size, ret;
  38 +       struct mtd_info *mtd;
  39 +       const char *part;
  40 +       const __be32 *list;
  41 +       phandle phandle;
  42 +       u32 mac_inc = 0;
  43 +       u8 mac[ETH_ALEN];
  44 +
  45 +       list = of_get_property(np, "mtd-mac-address", &size);
  46 +       if (!list || (size != (2 * sizeof(*list))))
  47 +               return NULL;
  48 +
  49 +       phandle = be32_to_cpup(list++);
  50 +       if (phandle)
  51 +               mtd_np = of_find_node_by_phandle(phandle);
  52 +
  53 +       if (!mtd_np)
  54 +               return NULL;
  55 +
  56 +       part = of_get_property(mtd_np, "label", NULL);
  57 +       if (!part)
  58 +               part = mtd_np->name;
  59 +
  60 +       mtd = get_mtd_device_nm(part);
  61 +       if (IS_ERR(mtd))
  62 +               return NULL;
  63 +
  64 +       ret = mtd_read(mtd, be32_to_cpup(list), 6, &retlen, mac);
  65 +       put_mtd_device(mtd);
  66 +
  67 +       if (!of_property_read_u32(np, "mtd-mac-address-increment", &mac_inc))
  68 +               mac[5] += mac_inc;
  69 +
  70 +       if (!is_valid_ether_addr(mac))
  71 +               return NULL;
  72 +
  73 +       prop = kzalloc(sizeof(*prop), GFP_KERNEL);
  74 +       if (!prop)
  75 +               return NULL;
  76 +
  77 +       prop->name = "mac-address";
  78 +       prop->length = ETH_ALEN;
  79 +       prop->value = kmemdup(mac, ETH_ALEN, GFP_KERNEL);
  80 +       if (!prop->value || of_add_property(np, prop))
  81 +               goto free;
  82 +
  83 +       return prop->value;
  84 +free:
  85 +       kfree(prop->value);
  86 +       kfree(prop);
  87 +#endif
  88 +       return NULL;
  89 +}
  90 +
  91  /**
  92   * Search the device tree for the best MAC address to use.  'mac-address' is
  93   * checked first, because that is supposed to contain to "most recent" MAC
  94 @@ -64,6 +125,9 @@ static const void *of_get_mac_addr(struc
  95   * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
  96   * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
  97   * but is all zeros.
  98 + *
  99 + * If a mtd-mac-address property exists, try to fetch the MAC address from the
 100 + * specified mtd device, and store it as a 'mac-address' property
 101  */
 102  const void *of_get_mac_address(struct device_node *np)
 103  {
 104 @@ -77,6 +141,10 @@ const void *of_get_mac_address(struct de
 105         if (addr)
 106                 return addr;
 107
 108 -       return of_get_mac_addr(np, "address");
 109 +       addr = of_get_mac_addr(np, "address");
 110 +       if (addr)
 111 +               return addr;
 112 +
 113 +       return of_get_mac_address_mtd(np);
 114  }
 115  EXPORT_SYMBOL(of_get_mac_address);