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