drivers/of/of_net.c

   1 /*
   2  * OF helpers for network devices.
   3  *
   4  * This file is released under the GPLv2
   5  *
   6  * Initially copied out of arch/powerpc/kernel/prom_parse.c
   7  */
   8 #include <linux/etherdevice.h>
   9 #include <linux/kernel.h>
  10 #include <linux/of_net.h>
  11 #include <linux/phy.h>
  12 #include <linux/export.h>
  13
  14 /**
  15  * It maps 'enum phy_interface_t' found in include/linux/phy.h
  16  * into the device tree binding of 'phy-mode', so that Ethernet
  17  * device driver can get phy interface from device tree.
  18  */
  19 static const char *phy_modes[] = {
  20         [PHY_INTERFACE_MODE_NA]         = "",
  21         [PHY_INTERFACE_MODE_MII]        = "mii",
  22         [PHY_INTERFACE_MODE_GMII]       = "gmii",
  23         [PHY_INTERFACE_MODE_SGMII]      = "sgmii",
  24         [PHY_INTERFACE_MODE_TBI]        = "tbi",
  25         [PHY_INTERFACE_MODE_REVMII]     = "rev-mii",
  26         [PHY_INTERFACE_MODE_RMII]       = "rmii",
  27         [PHY_INTERFACE_MODE_RGMII]      = "rgmii",
  28         [PHY_INTERFACE_MODE_RGMII_ID]   = "rgmii-id",
  29         [PHY_INTERFACE_MODE_RGMII_RXID] = "rgmii-rxid",
  30         [PHY_INTERFACE_MODE_RGMII_TXID] = "rgmii-txid",
  31         [PHY_INTERFACE_MODE_RTBI]       = "rtbi",
  32         [PHY_INTERFACE_MODE_SMII]       = "smii",
  33 };
  34
  35 /**
  36  * of_get_phy_mode - Get phy mode for given device_node
  37  * @np: Pointer to the given device_node
  38  *
  39  * The function gets phy interface string from property 'phy-mode',
  40  * and return its index in phy_modes table, or errno in error case.
  41  */
  42 int of_get_phy_mode(struct device_node *np)
  43 {
  44         const char *pm;
  45         int err, i;
  46
  47         err = of_property_read_string(np, "phy-mode", &pm);
  48         if (err < 0)
  49                 return err;
  50
  51         for (i = 0; i < ARRAY_SIZE(phy_modes); i++)
  52                 if (!strcasecmp(pm, phy_modes[i]))
  53                         return i;
  54
  55         return -ENODEV;
  56 }
  57 EXPORT_SYMBOL_GPL(of_get_phy_mode);
  58
  59 /**
  60  * Search the device tree for the best MAC address to use.  'mac-address' is
  61  * checked first, because that is supposed to contain to "most recent" MAC
  62  * address. If that isn't set, then 'local-mac-address' is checked next,
  63  * because that is the default address.  If that isn't set, then the obsolete
  64  * 'address' is checked, just in case we're using an old device tree.
  65  *
  66  * Note that the 'address' property is supposed to contain a virtual address of
  67  * the register set, but some DTS files have redefined that property to be the
  68  * MAC address.
  69  *
  70  * All-zero MAC addresses are rejected, because those could be properties that
  71  * exist in the device tree, but were not set by U-Boot.  For example, the
  72  * DTS could define 'mac-address' and 'local-mac-address', with zero MAC
  73  * addresses.  Some older U-Boots only initialized 'local-mac-address'.  In
  74  * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
  75  * but is all zeros.
  76 */
  77 const void *of_get_mac_address(struct device_node *np)
  78 {
  79         struct property *pp;
  80
  81         pp = of_find_property(np, "mac-address", NULL);
  82         if (pp && (pp->length == 6) && is_valid_ether_addr(pp->value))
  83                 return pp->value;
  84
  85         pp = of_find_property(np, "local-mac-address", NULL);
  86         if (pp && (pp->length == 6) && is_valid_ether_addr(pp->value))
  87                 return pp->value;
  88
  89         pp = of_find_property(np, "address", NULL);
  90         if (pp && (pp->length == 6) && is_valid_ether_addr(pp->value))
  91                 return pp->value;
  92
  93         return NULL;
  94 }
  95 EXPORT_SYMBOL(of_get_mac_address);