drivers/of/of_mdio.c

   1 /*
   2  * OF helpers for the MDIO (Ethernet PHY) API
   3  *
   4  * Copyright (c) 2009 Secret Lab Technologies, Ltd.
   5  *
   6  * This file is released under the GPLv2
   7  *
   8  * This file provides helper functions for extracting PHY device information
   9  * out of the OpenFirmware device tree and using it to populate an mii_bus.
  10  */
  11
  12 #include <linux/phy.h>
  13 #include <linux/of.h>
  14 #include <linux/of_mdio.h>
  15 #include <linux/module.h>
  16
  17 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  18 MODULE_LICENSE("GPL");
  19
  20 /**
  21  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
  22  * @mdio: pointer to mii_bus structure
  23  * @np: pointer to device_node of MDIO bus.
  24  *
  25  * This function registers the mii_bus structure and registers a phy_device
  26  * for each child node of @np.
  27  */
  28 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
  29 {
  30         struct phy_device *phy;
  31         struct device_node *child;
  32         int rc, i;
  33
  34         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
  35          * the device tree are populated after the bus has been registered */
  36         mdio->phy_mask = ~0;
  37
  38         /* Clear all the IRQ properties */
  39         if (mdio->irq)
  40                 for (i=0; i<PHY_MAX_ADDR; i++)
  41                         mdio->irq[i] = PHY_POLL;
  42
  43         /* Register the MDIO bus */
  44         rc = mdiobus_register(mdio);
  45         if (rc)
  46                 return rc;
  47
  48         /* Loop over the child nodes and register a phy_device for each one */
  49         for_each_child_of_node(np, child) {
  50                 const u32 *addr;
  51                 int len;
  52
  53                 /* A PHY must have a reg property in the range [0-31] */
  54                 addr = of_get_property(child, "reg", &len);
  55                 if (!addr || len < sizeof(*addr) || *addr >= 32 || *addr < 0) {
  56                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
  57                                 child->full_name);
  58                         continue;
  59                 }
  60
  61                 if (mdio->irq) {
  62                         mdio->irq[*addr] = irq_of_parse_and_map(child, 0);
  63                         if (!mdio->irq[*addr])
  64                                 mdio->irq[*addr] = PHY_POLL;
  65                 }
  66
  67                 phy = get_phy_device(mdio, *addr);
  68                 if (!phy) {
  69                         dev_err(&mdio->dev, "error probing PHY at address %i\n",
  70                                 *addr);
  71                         continue;
  72                 }
  73                 phy_scan_fixups(phy);
  74
  75                 /* Associate the OF node with the device structure so it
  76                  * can be looked up later */
  77                 of_node_get(child);
  78                 dev_archdata_set_node(&phy->dev.archdata, child);
  79
  80                 /* All data is now stored in the phy struct; register it */
  81                 rc = phy_device_register(phy);
  82                 if (rc) {
  83                         phy_device_free(phy);
  84                         of_node_put(child);
  85                         continue;
  86                 }
  87
  88                 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  89                         child->name, *addr);
  90         }
  91
  92         return 0;
  93 }
  94 EXPORT_SYMBOL(of_mdiobus_register);
  95
  96 /**
  97  * of_phy_find_device - Give a PHY node, find the phy_device
  98  * @phy_np: Pointer to the phy's device tree node
  99  *
 100  * Returns a pointer to the phy_device.
 101  */
 102 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 103 {
 104         struct device *d;
 105         int match(struct device *dev, void *phy_np)
 106         {
 107                 return dev_archdata_get_node(&dev->archdata) == phy_np;
 108         }
 109
 110         if (!phy_np)
 111                 return NULL;
 112
 113         d = bus_find_device(&mdio_bus_type, NULL, phy_np, match);
 114         return d ? to_phy_device(d) : NULL;
 115 }
 116 EXPORT_SYMBOL(of_phy_find_device);
 117
 118 /**
 119  * of_phy_connect - Connect to the phy described in the device tree
 120  * @dev: pointer to net_device claiming the phy
 121  * @phy_np: Pointer to device tree node for the PHY
 122  * @hndlr: Link state callback for the network device
 123  * @iface: PHY data interface type
 124  *
 125  * Returns a pointer to the phy_device if successfull.  NULL otherwise
 126  */
 127 struct phy_device *of_phy_connect(struct net_device *dev,
 128                                   struct device_node *phy_np,
 129                                   void (*hndlr)(struct net_device *), u32 flags,
 130                                   phy_interface_t iface)
 131 {
 132         struct phy_device *phy = of_phy_find_device(phy_np);
 133
 134         if (!phy)
 135                 return NULL;
 136
 137         return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
 138 }
 139 EXPORT_SYMBOL(of_phy_connect);