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