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 static void of_set_phy_supported(struct phy_device *phydev, u32 max_speed)
  26 {
  27         phydev->supported |= PHY_DEFAULT_FEATURES;
  28
  29         switch (max_speed) {
  30         default:
  31                 return;
  32
  33         case SPEED_1000:
  34                 phydev->supported |= PHY_1000BT_FEATURES;
  35         case SPEED_100:
  36                 phydev->supported |= PHY_100BT_FEATURES;
  37         case SPEED_10:
  38                 phydev->supported |= PHY_10BT_FEATURES;
  39         }
  40 }
  41
  42 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
  43                                    u32 addr)
  44 {
  45         struct phy_device *phy;
  46         bool is_c45;
  47         int rc, prev_irq;
  48         u32 max_speed = 0;
  49
  50         is_c45 = of_device_is_compatible(child,
  51                                          "ethernet-phy-ieee802.3-c45");
  52
  53         phy = get_phy_device(mdio, addr, is_c45);
  54         if (!phy || IS_ERR(phy))
  55                 return 1;
  56
  57         if (mdio->irq) {
  58                 prev_irq = mdio->irq[addr];
  59                 mdio->irq[addr] =
  60                         irq_of_parse_and_map(child, 0);
  61                 if (!mdio->irq[addr])
  62                         mdio->irq[addr] = prev_irq;
  63         }
  64
  65         /* Associate the OF node with the device structure so it
  66          * can be looked up later */
  67         of_node_get(child);
  68         phy->dev.of_node = child;
  69
  70         /* All data is now stored in the phy struct;
  71          * register it */
  72         rc = phy_device_register(phy);
  73         if (rc) {
  74                 phy_device_free(phy);
  75                 of_node_put(child);
  76                 return 1;
  77         }
  78
  79         /* Set phydev->supported based on the "max-speed" property
  80          * if present */
  81         if (!of_property_read_u32(child, "max-speed", &max_speed))
  82                 of_set_phy_supported(phy, max_speed);
  83
  84         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  85                 child->name, addr);
  86
  87         return 0;
  88 }
  89
  90 /**
  91  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
  92  * @mdio: pointer to mii_bus structure
  93  * @np: pointer to device_node of MDIO bus.
  94  *
  95  * This function registers the mii_bus structure and registers a phy_device
  96  * for each child node of @np.
  97  */
  98 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
  99 {
 100         struct device_node *child;
 101         const __be32 *paddr;
 102         u32 addr;
 103         bool scanphys = false;
 104         int rc, i, len;
 105
 106         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 107          * the device tree are populated after the bus has been registered */
 108         mdio->phy_mask = ~0;
 109
 110         /* Clear all the IRQ properties */
 111         if (mdio->irq)
 112                 for (i=0; i<PHY_MAX_ADDR; i++)
 113                         mdio->irq[i] = PHY_POLL;
 114
 115         mdio->dev.of_node = np;
 116
 117         /* Register the MDIO bus */
 118         rc = mdiobus_register(mdio);
 119         if (rc)
 120                 return rc;
 121
 122         /* Loop over the child nodes and register a phy_device for each one */
 123         for_each_available_child_of_node(np, child) {
 124                 /* A PHY must have a reg property in the range [0-31] */
 125                 paddr = of_get_property(child, "reg", &len);
 126                 if (!paddr || len < sizeof(*paddr)) {
 127                         scanphys = true;
 128                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
 129                                 child->full_name);
 130                         continue;
 131                 }
 132
 133                 addr = be32_to_cpup(paddr);
 134                 if (addr >= PHY_MAX_ADDR) {
 135                         dev_err(&mdio->dev, "%s PHY address %i is too large\n",
 136                                 child->full_name, addr);
 137                         continue;
 138                 }
 139
 140                 rc = of_mdiobus_register_phy(mdio, child, addr);
 141                 if (rc)
 142                         continue;
 143         }
 144
 145         if (!scanphys)
 146                 return 0;
 147
 148         /* auto scan for PHYs with empty reg property */
 149         for_each_available_child_of_node(np, child) {
 150                 /* Skip PHYs with reg property set */
 151                 paddr = of_get_property(child, "reg", &len);
 152                 if (paddr)
 153                         continue;
 154
 155                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 156                         /* skip already registered PHYs */
 157                         if (mdio->phy_map[addr])
 158                                 continue;
 159
 160                         /* be noisy to encourage people to set reg property */
 161                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 162                                  child->name, addr);
 163
 164                         rc = of_mdiobus_register_phy(mdio, child, addr);
 165                         if (rc)
 166                                 continue;
 167                 }
 168         }
 169
 170         return 0;
 171 }
 172 EXPORT_SYMBOL(of_mdiobus_register);
 173
 174 /* Helper function for of_phy_find_device */
 175 static int of_phy_match(struct device *dev, void *phy_np)
 176 {
 177         return dev->of_node == phy_np;
 178 }
 179
 180 /**
 181  * of_phy_find_device - Give a PHY node, find the phy_device
 182  * @phy_np: Pointer to the phy's device tree node
 183  *
 184  * Returns a pointer to the phy_device.
 185  */
 186 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 187 {
 188         struct device *d;
 189         if (!phy_np)
 190                 return NULL;
 191
 192         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 193         return d ? to_phy_device(d) : NULL;
 194 }
 195 EXPORT_SYMBOL(of_phy_find_device);
 196
 197 /**
 198  * of_phy_connect - Connect to the phy described in the device tree
 199  * @dev: pointer to net_device claiming the phy
 200  * @phy_np: Pointer to device tree node for the PHY
 201  * @hndlr: Link state callback for the network device
 202  * @iface: PHY data interface type
 203  *
 204  * Returns a pointer to the phy_device if successful.  NULL otherwise
 205  */
 206 struct phy_device *of_phy_connect(struct net_device *dev,
 207                                   struct device_node *phy_np,
 208                                   void (*hndlr)(struct net_device *), u32 flags,
 209                                   phy_interface_t iface)
 210 {
 211         struct phy_device *phy = of_phy_find_device(phy_np);
 212
 213         if (!phy)
 214                 return NULL;
 215
 216         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 217 }
 218 EXPORT_SYMBOL(of_phy_connect);
 219
 220 /**
 221  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 222  * @dev: pointer to net_device claiming the phy
 223  * @hndlr: Link state callback for the network device
 224  * @iface: PHY data interface type
 225  *
 226  * This function is a temporary stop-gap and will be removed soon.  It is
 227  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 228  * not call this function from new drivers.
 229  */
 230 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 231                                              void (*hndlr)(struct net_device *),
 232                                              phy_interface_t iface)
 233 {
 234         struct device_node *net_np;
 235         char bus_id[MII_BUS_ID_SIZE + 3];
 236         struct phy_device *phy;
 237         const __be32 *phy_id;
 238         int sz;
 239
 240         if (!dev->dev.parent)
 241                 return NULL;
 242
 243         net_np = dev->dev.parent->of_node;
 244         if (!net_np)
 245                 return NULL;
 246
 247         phy_id = of_get_property(net_np, "fixed-link", &sz);
 248         if (!phy_id || sz < sizeof(*phy_id))
 249                 return NULL;
 250
 251         sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
 252
 253         phy = phy_connect(dev, bus_id, hndlr, iface);
 254         return IS_ERR(phy) ? NULL : phy;
 255 }
 256 EXPORT_SYMBOL(of_phy_connect_fixed_link);
 257
 258 /**
 259  * of_phy_attach - Attach to a PHY without starting the state machine
 260  * @dev: pointer to net_device claiming the phy
 261  * @phy_np: Node pointer for the PHY
 262  * @flags: flags to pass to the PHY
 263  * @iface: PHY data interface type
 264  */
 265 struct phy_device *of_phy_attach(struct net_device *dev,
 266                                  struct device_node *phy_np, u32 flags,
 267                                  phy_interface_t iface)
 268 {
 269         struct phy_device *phy = of_phy_find_device(phy_np);
 270
 271         if (!phy)
 272                 return NULL;
 273
 274         return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
 275 }
 276 EXPORT_SYMBOL(of_phy_attach);