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         mdio->dev.of_node = np;
  49
  50         /* Register the MDIO bus */
  51         rc = mdiobus_register(mdio);
  52         if (rc)
  53                 return rc;
  54
  55         /* Loop over the child nodes and register a phy_device for each one */
  56         for_each_available_child_of_node(np, child) {
  57                 const __be32 *paddr;
  58                 u32 addr;
  59                 int len;
  60                 bool is_c45;
  61
  62                 /* A PHY must have a reg property in the range [0-31] */
  63                 paddr = of_get_property(child, "reg", &len);
  64                 if (!paddr || len < sizeof(*paddr)) {
  65                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
  66                                 child->full_name);
  67                         continue;
  68                 }
  69
  70                 addr = be32_to_cpup(paddr);
  71                 if (addr >= 32) {
  72                         dev_err(&mdio->dev, "%s PHY address %i is too large\n",
  73                                 child->full_name, addr);
  74                         continue;
  75                 }
  76
  77                 if (mdio->irq) {
  78                         mdio->irq[addr] = irq_of_parse_and_map(child, 0);
  79                         if (!mdio->irq[addr])
  80                                 mdio->irq[addr] = PHY_POLL;
  81                 }
  82
  83                 is_c45 = of_device_is_compatible(child,
  84                                                  "ethernet-phy-ieee802.3-c45");
  85                 phy = get_phy_device(mdio, addr, is_c45);
  86
  87                 if (!phy || IS_ERR(phy)) {
  88                         phy = phy_device_create(mdio, addr, 0, false, NULL);
  89                         if (!phy || IS_ERR(phy)) {
  90                                 dev_err(&mdio->dev,
  91                                         "error creating PHY at address %i\n",
  92                                         addr);
  93                                 continue;
  94                         }
  95                 }
  96
  97                 /* Associate the OF node with the device structure so it
  98                  * can be looked up later */
  99                 of_node_get(child);
 100                 phy->dev.of_node = child;
 101
 102                 /* All data is now stored in the phy struct; register it */
 103                 rc = phy_device_register(phy);
 104                 if (rc) {
 105                         phy_device_free(phy);
 106                         of_node_put(child);
 107                         continue;
 108                 }
 109
 110                 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
 111                         child->name, addr);
 112         }
 113
 114         return 0;
 115 }
 116 EXPORT_SYMBOL(of_mdiobus_register);
 117
 118 /* Helper function for of_phy_find_device */
 119 static int of_phy_match(struct device *dev, void *phy_np)
 120 {
 121         return dev->of_node == phy_np;
 122 }
 123
 124 /**
 125  * of_phy_find_device - Give a PHY node, find the phy_device
 126  * @phy_np: Pointer to the phy's device tree node
 127  *
 128  * Returns a pointer to the phy_device.
 129  */
 130 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 131 {
 132         struct device *d;
 133         if (!phy_np)
 134                 return NULL;
 135
 136         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 137         return d ? to_phy_device(d) : NULL;
 138 }
 139 EXPORT_SYMBOL(of_phy_find_device);
 140
 141 /**
 142  * of_phy_connect - Connect to the phy described in the device tree
 143  * @dev: pointer to net_device claiming the phy
 144  * @phy_np: Pointer to device tree node for the PHY
 145  * @hndlr: Link state callback for the network device
 146  * @iface: PHY data interface type
 147  *
 148  * Returns a pointer to the phy_device if successful.  NULL otherwise
 149  */
 150 struct phy_device *of_phy_connect(struct net_device *dev,
 151                                   struct device_node *phy_np,
 152                                   void (*hndlr)(struct net_device *), u32 flags,
 153                                   phy_interface_t iface)
 154 {
 155         struct phy_device *phy = of_phy_find_device(phy_np);
 156
 157         if (!phy)
 158                 return NULL;
 159
 160         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 161 }
 162 EXPORT_SYMBOL(of_phy_connect);
 163
 164 /**
 165  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 166  * @dev: pointer to net_device claiming the phy
 167  * @hndlr: Link state callback for the network device
 168  * @iface: PHY data interface type
 169  *
 170  * This function is a temporary stop-gap and will be removed soon.  It is
 171  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 172  * not call this function from new drivers.
 173  */
 174 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 175                                              void (*hndlr)(struct net_device *),
 176                                              phy_interface_t iface)
 177 {
 178         struct device_node *net_np;
 179         char bus_id[MII_BUS_ID_SIZE + 3];
 180         struct phy_device *phy;
 181         const __be32 *phy_id;
 182         int sz;
 183
 184         if (!dev->dev.parent)
 185                 return NULL;
 186
 187         net_np = dev->dev.parent->of_node;
 188         if (!net_np)
 189                 return NULL;
 190
 191         phy_id = of_get_property(net_np, "fixed-link", &sz);
 192         if (!phy_id || sz < sizeof(*phy_id))
 193                 return NULL;
 194
 195         sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
 196
 197         phy = phy_connect(dev, bus_id, hndlr, iface);
 198         return IS_ERR(phy) ? NULL : phy;
 199 }
 200 EXPORT_SYMBOL(of_phy_connect_fixed_link);