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         const __be32 *paddr;
  38         u32 addr;
  39         bool is_c45, scanphys = false;
  40         int rc, i, len;
  41
  42         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
  43          * the device tree are populated after the bus has been registered */
  44         mdio->phy_mask = ~0;
  45
  46         /* Clear all the IRQ properties */
  47         if (mdio->irq)
  48                 for (i=0; i<PHY_MAX_ADDR; i++)
  49                         mdio->irq[i] = PHY_POLL;
  50
  51         mdio->dev.of_node = np;
  52
  53         /* Register the MDIO bus */
  54         rc = mdiobus_register(mdio);
  55         if (rc)
  56                 return rc;
  57
  58         /* Loop over the child nodes and register a phy_device for each one */
  59         for_each_available_child_of_node(np, child) {
  60                 /* A PHY must have a reg property in the range [0-31] */
  61                 paddr = of_get_property(child, "reg", &len);
  62                 if (!paddr || len < sizeof(*paddr)) {
  63                         scanphys = true;
  64                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
  65                                 child->full_name);
  66                         continue;
  67                 }
  68
  69                 addr = be32_to_cpup(paddr);
  70                 if (addr >= 32) {
  71                         dev_err(&mdio->dev, "%s PHY address %i is too large\n",
  72                                 child->full_name, addr);
  73                         continue;
  74                 }
  75
  76                 if (mdio->irq) {
  77                         mdio->irq[addr] = irq_of_parse_and_map(child, 0);
  78                         if (!mdio->irq[addr])
  79                                 mdio->irq[addr] = PHY_POLL;
  80                 }
  81
  82                 is_c45 = of_device_is_compatible(child,
  83                                                  "ethernet-phy-ieee802.3-c45");
  84                 phy = get_phy_device(mdio, addr, is_c45);
  85
  86                 if (!phy || IS_ERR(phy)) {
  87                         dev_err(&mdio->dev,
  88                                 "cannot get PHY at address %i\n",
  89                                 addr);
  90                         continue;
  91                 }
  92
  93                 /* Associate the OF node with the device structure so it
  94                  * can be looked up later */
  95                 of_node_get(child);
  96                 phy->dev.of_node = child;
  97
  98                 /* All data is now stored in the phy struct; register it */
  99                 rc = phy_device_register(phy);
 100                 if (rc) {
 101                         phy_device_free(phy);
 102                         of_node_put(child);
 103                         continue;
 104                 }
 105
 106                 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
 107                         child->name, addr);
 108         }
 109
 110         if (!scanphys)
 111                 return 0;
 112
 113         /* auto scan for PHYs with empty reg property */
 114         for_each_available_child_of_node(np, child) {
 115                 /* Skip PHYs with reg property set */
 116                 paddr = of_get_property(child, "reg", &len);
 117                 if (paddr)
 118                         continue;
 119
 120                 is_c45 = of_device_is_compatible(child,
 121                                                  "ethernet-phy-ieee802.3-c45");
 122
 123                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 124                         /* skip already registered PHYs */
 125                         if (mdio->phy_map[addr])
 126                                 continue;
 127
 128                         /* be noisy to encourage people to set reg property */
 129                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 130                                  child->name, addr);
 131
 132                         phy = get_phy_device(mdio, addr, is_c45);
 133                         if (!phy || IS_ERR(phy))
 134                                 continue;
 135
 136                         if (mdio->irq) {
 137                                 mdio->irq[addr] =
 138                                         irq_of_parse_and_map(child, 0);
 139                                 if (!mdio->irq[addr])
 140                                         mdio->irq[addr] = PHY_POLL;
 141                         }
 142
 143                         /* Associate the OF node with the device structure so it
 144                          * can be looked up later */
 145                         of_node_get(child);
 146                         phy->dev.of_node = child;
 147
 148                         /* All data is now stored in the phy struct;
 149                          * register it */
 150                         rc = phy_device_register(phy);
 151                         if (rc) {
 152                                 phy_device_free(phy);
 153                                 of_node_put(child);
 154                                 continue;
 155                         }
 156
 157                         dev_info(&mdio->dev, "registered phy %s at address %i\n",
 158                                  child->name, addr);
 159                         break;
 160                 }
 161         }
 162
 163         return 0;
 164 }
 165 EXPORT_SYMBOL(of_mdiobus_register);
 166
 167 /* Helper function for of_phy_find_device */
 168 static int of_phy_match(struct device *dev, void *phy_np)
 169 {
 170         return dev->of_node == phy_np;
 171 }
 172
 173 /**
 174  * of_phy_find_device - Give a PHY node, find the phy_device
 175  * @phy_np: Pointer to the phy's device tree node
 176  *
 177  * Returns a pointer to the phy_device.
 178  */
 179 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 180 {
 181         struct device *d;
 182         if (!phy_np)
 183                 return NULL;
 184
 185         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 186         return d ? to_phy_device(d) : NULL;
 187 }
 188 EXPORT_SYMBOL(of_phy_find_device);
 189
 190 /**
 191  * of_phy_connect - Connect to the phy described in the device tree
 192  * @dev: pointer to net_device claiming the phy
 193  * @phy_np: Pointer to device tree node for the PHY
 194  * @hndlr: Link state callback for the network device
 195  * @iface: PHY data interface type
 196  *
 197  * Returns a pointer to the phy_device if successful.  NULL otherwise
 198  */
 199 struct phy_device *of_phy_connect(struct net_device *dev,
 200                                   struct device_node *phy_np,
 201                                   void (*hndlr)(struct net_device *), u32 flags,
 202                                   phy_interface_t iface)
 203 {
 204         struct phy_device *phy = of_phy_find_device(phy_np);
 205
 206         if (!phy)
 207                 return NULL;
 208
 209         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 210 }
 211 EXPORT_SYMBOL(of_phy_connect);
 212
 213 /**
 214  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 215  * @dev: pointer to net_device claiming the phy
 216  * @hndlr: Link state callback for the network device
 217  * @iface: PHY data interface type
 218  *
 219  * This function is a temporary stop-gap and will be removed soon.  It is
 220  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 221  * not call this function from new drivers.
 222  */
 223 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 224                                              void (*hndlr)(struct net_device *),
 225                                              phy_interface_t iface)
 226 {
 227         struct device_node *net_np;
 228         char bus_id[MII_BUS_ID_SIZE + 3];
 229         struct phy_device *phy;
 230         const __be32 *phy_id;
 231         int sz;
 232
 233         if (!dev->dev.parent)
 234                 return NULL;
 235
 236         net_np = dev->dev.parent->of_node;
 237         if (!net_np)
 238                 return NULL;
 239
 240         phy_id = of_get_property(net_np, "fixed-link", &sz);
 241         if (!phy_id || sz < sizeof(*phy_id))
 242                 return NULL;
 243
 244         sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
 245
 246         phy = phy_connect(dev, bus_id, hndlr, iface);
 247         return IS_ERR(phy) ? NULL : phy;
 248 }
 249 EXPORT_SYMBOL(of_phy_connect_fixed_link);