LXR linux/drivers/of/of

   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/kernel.h>
  13#include <linux/device.h>
  14#include <linux/netdevice.h>
  15#include <linux/err.h>
  16#include <linux/phy.h>
  17#include <linux/of.h>
  18#include <linux/of_irq.h>
  19#include <linux/of_mdio.h>
  20#include <linux/module.h>
  21
  22MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  23MODULE_LICENSE("GPL");
  24
  25/**
  26 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
  27 * @mdio: pointer to mii_bus structure
  28 * @np: pointer to device_node of MDIO bus.
  29 *
  30 * This function registers the mii_bus structure and registers a phy_device
  31 * for each child node of @np.
  32 */
  33int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
  34{
  35        struct phy_device *phy;
  36        struct device_node *child;
  37        int rc, i;
  38
  39        /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
  40         * the device tree are populated after the bus has been registered */
  41        mdio->phy_mask = ~0;
  42
  43        /* Clear all the IRQ properties */
  44        if (mdio->irq)
  45                for (i=0; i<PHY_MAX_ADDR; i++)
  46                        mdio->irq[i] = PHY_POLL;
  47
  48        /* Register the MDIO bus */
  49        rc = mdiobus_register(mdio);
  50        if (rc)
  51                return rc;
  52
  53        /* Loop over the child nodes and register a phy_device for each one */
  54        for_each_child_of_node(np, child) {
  55                const __be32 *paddr;
  56                u32 addr;
  57                int len;
  58
  59                /* A PHY must have a reg property in the range [0-31] */
  60                paddr = of_get_property(child, "reg", &len);
  61                if (!paddr || len < sizeof(*paddr)) {
  62                        dev_err(&mdio->dev, "%s has invalid PHY address\n",
  63                                child->full_name);
  64                        continue;
  65                }
  66
  67                addr = be32_to_cpup(paddr);
  68                if (addr >= 32) {
  69                        dev_err(&mdio->dev, "%s PHY address %i is too large\n",
  70                                child->full_name, addr);
  71                        continue;
  72                }
  73
  74                if (mdio->irq) {
  75                        mdio->irq[addr] = irq_of_parse_and_map(child, 0);
  76                        if (!mdio->irq[addr])
  77                                mdio->irq[addr] = PHY_POLL;
  78                }
  79
  80                phy = get_phy_device(mdio, addr);
  81                if (!phy || IS_ERR(phy)) {
  82                        dev_err(&mdio->dev, "error probing PHY at address %i\n",
  83                                addr);
  84                        continue;
  85                }
  86                phy_scan_fixups(phy);
  87
  88                /* Associate the OF node with the device structure so it
  89                 * can be looked up later */
  90                of_node_get(child);
  91                phy->dev.of_node = child;
  92
  93                /* All data is now stored in the phy struct; register it */
  94                rc = phy_device_register(phy);
  95                if (rc) {
  96                        phy_device_free(phy);
  97                        of_node_put(child);
  98                        continue;
  99                }
 100
 101                dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
 102                        child->name, addr);
 103        }
 104
 105        return 0;
 106}
 107EXPORT_SYMBOL(of_mdiobus_register);
 108
 109/* Helper function for of_phy_find_device */
 110static int of_phy_match(struct device *dev, void *phy_np)
 111{
 112        return dev->of_node == phy_np;
 113}
 114
 115/**
 116 * of_phy_find_device - Give a PHY node, find the phy_device
 117 * @phy_np: Pointer to the phy's device tree node
 118 *
 119 * Returns a pointer to the phy_device.
 120 */
 121struct phy_device *of_phy_find_device(struct device_node *phy_np)
 122{
 123        struct device *d;
 124        if (!phy_np)
 125                return NULL;
 126
 127        d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 128        return d ? to_phy_device(d) : NULL;
 129}
 130EXPORT_SYMBOL(of_phy_find_device);
 131
 132/**
 133 * of_phy_connect - Connect to the phy described in the device tree
 134 * @dev: pointer to net_device claiming the phy
 135 * @phy_np: Pointer to device tree node for the PHY
 136 * @hndlr: Link state callback for the network device
 137 * @iface: PHY data interface type
 138 *
 139 * Returns a pointer to the phy_device if successful.  NULL otherwise
 140 */
 141struct phy_device *of_phy_connect(struct net_device *dev,
 142                                  struct device_node *phy_np,
 143                                  void (*hndlr)(struct net_device *), u32 flags,
 144                                  phy_interface_t iface)
 145{
 146        struct phy_device *phy = of_phy_find_device(phy_np);
 147
 148        if (!phy)
 149                return NULL;
 150
 151        return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
 152}
 153EXPORT_SYMBOL(of_phy_connect);
 154
 155/**
 156 * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 157 * @dev: pointer to net_device claiming the phy
 158 * @hndlr: Link state callback for the network device
 159 * @iface: PHY data interface type
 160 *
 161 * This function is a temporary stop-gap and will be removed soon.  It is
 162 * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 163 * not call this function from new drivers.
 164 */
 165struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 166                                             void (*hndlr)(struct net_device *),
 167                                             phy_interface_t iface)
 168{
 169        struct device_node *net_np;
 170        char bus_id[MII_BUS_ID_SIZE + 3];
 171        struct phy_device *phy;
 172        const __be32 *phy_id;
 173        int sz;
 174
 175        if (!dev->dev.parent)
 176                return NULL;
 177
 178        net_np = dev->dev.parent->of_node;
 179        if (!net_np)
 180                return NULL;
 181
 182        phy_id = of_get_property(net_np, "fixed-link", &sz);
 183        if (!phy_id || sz < sizeof(*phy_id))
 184                return NULL;
 185
 186        sprintf(bus_id, PHY_ID_FMT, "0", be32_to_cpu(phy_id[0]));
 187
 188        phy = phy_connect(dev, bus_id, hndlr, 0, iface);
 189        return IS_ERR(phy) ? NULL : phy;
 190}
 191EXPORT_SYMBOL(of_phy_connect_fixed_link);
 192