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/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
  22 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  23 MODULE_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  */
  33 int 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
  87                 /* Associate the OF node with the device structure so it
  88                  * can be looked up later */
  89                 of_node_get(child);
  90                 phy->dev.of_node = child;
  91
  92                 /* All data is now stored in the phy struct; register it */
  93                 rc = phy_device_register(phy);
  94                 if (rc) {
  95                         phy_device_free(phy);
  96                         of_node_put(child);
  97                         continue;
  98                 }
  99
 100                 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
 101                         child->name, addr);
 102         }
 103
 104         return 0;
 105 }
 106 EXPORT_SYMBOL(of_mdiobus_register);
 107
 108 /* Helper function for of_phy_find_device */
 109 static int of_phy_match(struct device *dev, void *phy_np)
 110 {
 111         return dev->of_node == phy_np;
 112 }
 113
 114 /**
 115  * of_phy_find_device - Give a PHY node, find the phy_device
 116  * @phy_np: Pointer to the phy's device tree node
 117  *
 118  * Returns a pointer to the phy_device.
 119  */
 120 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 121 {
 122         struct device *d;
 123         if (!phy_np)
 124                 return NULL;
 125
 126         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 127         return d ? to_phy_device(d) : NULL;
 128 }
 129 EXPORT_SYMBOL(of_phy_find_device);
 130
 131 /**
 132  * of_phy_connect - Connect to the phy described in the device tree
 133  * @dev: pointer to net_device claiming the phy
 134  * @phy_np: Pointer to device tree node for the PHY
 135  * @hndlr: Link state callback for the network device
 136  * @iface: PHY data interface type
 137  *
 138  * Returns a pointer to the phy_device if successful.  NULL otherwise
 139  */
 140 struct phy_device *of_phy_connect(struct net_device *dev,
 141                                   struct device_node *phy_np,
 142                                   void (*hndlr)(struct net_device *), u32 flags,
 143                                   phy_interface_t iface)
 144 {
 145         struct phy_device *phy = of_phy_find_device(phy_np);
 146
 147         if (!phy)
 148                 return NULL;
 149
 150         return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
 151 }
 152 EXPORT_SYMBOL(of_phy_connect);
 153
 154 /**
 155  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 156  * @dev: pointer to net_device claiming the phy
 157  * @hndlr: Link state callback for the network device
 158  * @iface: PHY data interface type
 159  *
 160  * This function is a temporary stop-gap and will be removed soon.  It is
 161  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 162  * not call this function from new drivers.
 163  */
 164 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 165                                              void (*hndlr)(struct net_device *),
 166                                              phy_interface_t iface)
 167 {
 168         struct device_node *net_np;
 169         char bus_id[MII_BUS_ID_SIZE + 3];
 170         struct phy_device *phy;
 171         const __be32 *phy_id;
 172         int sz;
 173
 174         if (!dev->dev.parent)
 175                 return NULL;
 176
 177         net_np = dev->dev.parent->of_node;
 178         if (!net_np)
 179                 return NULL;
 180
 181         phy_id = of_get_property(net_np, "fixed-link", &sz);
 182         if (!phy_id || sz < sizeof(*phy_id))
 183                 return NULL;
 184
 185         sprintf(bus_id, PHY_ID_FMT, "0", be32_to_cpu(phy_id[0]));
 186
 187         phy = phy_connect(dev, bus_id, hndlr, 0, iface);
 188         return IS_ERR(phy) ? NULL : phy;
 189 }
 190 EXPORT_SYMBOL(of_phy_connect_fixed_link);